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Oncology

Clinical Articles

Bowel Cancer Screening: Who, When, How?

New NHMRC guidelines put age and family history up front and centre in determining who should be screened for bowel cancer with colonoscopy and who needs iFOBT. It has been known for some time that family history can influence the risk of developing bowel cancer, Australia’s second most common cause of cancer death. But it is also known that specific, identified genetic mutations causing conditions such as Lynch syndrome or familial adenomatous polyposis are rare, accounting for less than 5% of all bowel cancers diagnosed. At most, the researchers say, this only explains half of the reasons why family history is a risk factor for bowel cancer. “The remainder of the observed increases in familial risk could be due in part to mutations in yet to be discovered colorectal cancer susceptibility genes, polygenic factors such as single-nucleotide polymorphisms, or dietary and other lifestyle factors shared by family members,” the guideline authors said in the Medical Journal of Australia. Therefore, the researchers, led by Professor Mark Jenkins, director of the Centre for Epidemiology and Biostatistics, in the University of Melbourne’s School of Population and Global Health, analysed all the available cohort studies to determine the risk of developing colorectal cancer based on age and family history. They categorised cohorts into one of three levels of risk and this determined at what age screening would be worthwhile starting and which screening method was most appropriate. The screening guidelines exclude people with a known or suspected cancer-causing genetic syndrome, as these people require much more intensive screening and should be managed in a family cancer clinic. The majority of Australians (90%) fall into the lowest risk category, category 1, which puts their risk at age 40 of developing colorectal cancer in the next 10 years at about 0.25% (one in 400). As with most other cancers age is a risk factor, so it is unsurprising that at age 50 the risk of developing this cancer has risen to 0.9%. Screening for this category 1 group should be the two-yearly iFOBT test that is currently available via the National Bowel Screening program for adults between the ages of 50 and 74 years. Interestingly, people aged 75 and older still develop bowel cancer but there have been no studies to determine the cost-effectiveness or benefit vs risk analysis of screening in this age group which is why the program and the guideline recommendations stop at 74 years. One of the differences in these new guidelines, a revision from the previous ones published back in 2005, is that people with a first degree relative who has had or has a bowel cancer at age 55 or older are still considered at average risk (category 1). However, people with this history might consider starting the iFOBT screening at a younger age (45 years), the guideline authors suggest. Category 2 includes people with a moderately increased risk of developing colorectal cancer, 3-6 times higher than average. This will mean having a first degree relative diagnosed with a bowel cancer before the age of 55 or having two first degree relatives who developed bowel cancer at any age (or one first degree and two second degree relatives). Category 2 people are recommended to have iFOBT every two years for the decade between ages 40 and 50 and then switch to five yearly colonoscopies until the age of 75. Finally, the high risk, category 3 is for all those patients without a genetic syndrome whose family history is even stronger than those people in category 2. Their risk is between 7-10 times higher than average. This includes people with at least three first-degree relatives who have been diagnosed with colorectal cancer at any age or people who have multiple relatives with the cancer including at least one diagnosed before aged 55. These high-risk people need to start screening earlier, with the guidelines recommending iFOBT every two years starting at age 35 and continuing for 10 years and then having a colonoscopy every five years between the ages of 45 and 75. Of note is that the revised guidelines have deleted the reference in the previous guidelines to starting screening 10 years before the earliest age colorectal cancer was diagnosed in a first degree relative. “There have been no studies conducted to determine the utility of beginning screening 10 years before the earliest diagnosis in the family, which was a recommendation in the 2005 guidelines and, therefore, it is not included in these guidelines,” they said. The new guidelines aim not only to more strongly define risk based on the latest evidence, but also to determine the most appropriate screening method based on that risk, taking into consideration cost-effectiveness and rationalisation of available services, in particular, colonoscopies. Reference Jenkins MA, Ouakrim DA, Boussioutas A, Hopper JL, Ee HC, Emery JD, et al. Revised Australian national guidelines for colorectal cancer screening: family history. Med J Aust. 2018 Oct 29. doi: 10.5694/mja18.00142. [epub ahead of print]

By Dr Linda Calabresi

Respiratory and sleep

Clinical Articles

Changes to Medicare for Home Sleep Study Testing

There are new changes to Medicare from November 1, 2018, which will affect how GPs can order sleep studies and how they follow up the results. These changes have been introduced by the MBS Review Taskforce and Government to improve doctor assessment and management of a patient having a sleep study.

What are the new Medicare changes?

From November 1 2018:

GPs will need to administer screening questionnaires before directly ordering a Medicare rebatable sleep study.
Only if these screening questionnaires are positive, can GPs refer directly for a Medicare rebatable sleep study test.
The screening questionnaires restrict testing to patients with a “high probability for symptomatic, moderate to severe obstructive sleep apnoea”.
Following sleep study testing, “the results and treatment options following any diagnostic sleep study should be discussed during a professional attendance with a medical practitioner before the initiation of any therapy”.

If the screening questionnaires are not positive, patients will need to be referred to Sleep or Respiratory Physicians for assessment and testing. Diagnostic sleep studies can only be rebated once a year.

Why were the changes made?

The MBS Review Taskforce noted a very large growth in sleep study testing, especially home sleep study testing, and were concerned that better access to testing has been associated with less appropriate referrals for testing. The Taskforce noted a lack of Sleep or Respiratory Physician review of patients for advice regarding the diagnosis and treatment of OSA. Related to this was a concern that some models of care were promoting home sleep study testing and then advising patients to proceed to CPAP “at lower apnoea-hypopnoea index (AHI) thresholds than is conventionally recommended as indicative of OSA requiring treatment.” The Taskforce commented that there may be a “commencement on CPAP which in some cases is not clinically indicated and does not address their sleep related problem. In this (later) scenario, patients purchase CPAP devices that may deliver little benefit, often based on advice from non-health professionals, and with no medical consultation involved.”

What do GPs need to do differently?

For adult sleep disorders, GPs can refer to a Sleep or Respiratory Physician for further testing and management (unchanged). This is particularly relevant and important if the patient has atypical symptoms of OSA; have a BMI > 30 and obesity hypoventilation is suspected; or they have symptoms of non-OSA sleep disorders that require management (e.g. insomnia, parasomnias, restless legs syndrome, primary hypersomnolence, etc.) OR GPs can refer directly for a sleep study to investigate OSA (subject to the new specific rules below) Direct referral for a sleep study by a GP should be for patients who have a high probability for symptomatic, moderate to severe obstructive sleep apnoea using the following screening tools:

An Epworth Sleepiness Scale score of 8 or more; AND
One of the following
- A STOP-BANG score of 4 or more; or
- An OSA-50 score of 5 or more; or
- A high risk score on the Berlin Questionnaire.

The screening questionnaires must be administered by the referring practitioner. Unattended (home) sleep studies are suitable for many patients with suspected OSA but patients with other sleep disorders should undergo an attended (laboratory) study. If GPs refer direct for sleep study testing, a doctor (GP or Sleep/Respiratory Physician) should see the patient after the test to discuss the results and advise on the best management for the patient’s sleep condition.

The future for primary care and sleep disorders

GPs and Sleep Specialists need to work closely together to co-manage the range and high prevalence of sleep disorders. The new Medicare rules place a greater emphasis on medical assessment, before and after sleep study testing, and emphasise the important role that doctors need to take in managing these conditions.

Summary:

For a GP to refer directly for a sleep study, the relevant questionnaires need to be attached to the referral for it to be valid.
Sleep or Respiratory Physician referrals do not need the questionnaires to be filled in.
Patients must be seen by a doctor before the study for the questionnaires to be filled, and after the study,before any treatment is initiated.
The number of Medicare rebatable sleep studies per patient per year has been limited.

Screening questionnaires:

See link: http://www.sleepcentres.com.au/tl_files/PDF/referral_form_PDF.pdf See tables attached.

Epworth Sleepiness Scale

OSA-50 Questionnaire

STOP-BANG Questionnaire

Berlin Questionnaire

By Healthed

Public health

Clinical Articles

Health Risks of Light Drinking in Pregnancy Confirms that Abstention is the Safest Approach

While heavy drinking is clearly harmful to the unborn baby, often leading to miscarriage, premature birth and foetal alcohol syndrome, the possible effects of light drinking have been less clear. High quality data on this issue is lacking due to ethical and methodological issues. On the one hand, experiments (clinical trials) in this area are impossible to conduct. Clinical trials would include randomising a group of pregnant women to drinking alcohol, which is clearly unethical. On the other hand, in observational studies we can never be sure whether the results are due to alcohol or other factors, such as wealth or education.

‘One glass is OK, isn’t it?’

Women often ask about “safe” levels of drinking during pregnancy. The distinction between light drinking and abstinence is indeed the point of most tension and confusion for health professionals and pregnant women, and public health guidance varies worldwide. Our new review of the evidence, published in BMJ Open, shows that this specific question is not being researched thoroughly enough. As there can be no clinical trial research carried out on this topic, we systematically reviewed all the data from a wide range of high quality observational studies. These studies involved pregnant women, or women trying to conceive, who reported on their alcohol use before the baby was born. The researchers assessed the impact of light drinking, compared with no alcohol at all. >> Read More Source: The Conversation

By Loubaba Mamluk, Luisa Zuccolo

Diabetes and metabolism

Clinical Articles

The Risks Associated with Gestational Diabetes Don’t End After Pregnancy

In Australia 12-14% of pregnancies are affected by gestational diabetes. Despite its prevalence, most people aren’t aware the risks don’t end when the pregnancy does. Diabetes occurs when the level of glucose (sugar) in the blood is higher than normal. Cells in the pancreas control blood glucose levels by producing insulin. When these cells are destroyed, type 1 diabetes results. When the body becomes resistant to the action of insulin and not enough insulin can be made, this is known as type 2 diabetes. Resistance to insulin action occurs for many reasons, including increasing age and body fat, low physical activity, hormone changes, and genetic makeup. Gestational diabetes occurs when high blood glucose levels are detected for the first time during pregnancy. Infrequently, this is due to previously undiagnosed diabetes. More commonly, the diabetes is only related to pregnancy. Pregnancy hormones reduce insulin action and increase insulin demand, in a similar way to type 2 diabetes, but usually after the baby is born, hormones and blood glucose levels go back to normal. Read more: Weight gain during pregnancy: how much is too much?

Who gets gestational diabetes?

Factors that increase the risk of gestational diabetes include:

a strong family history of diabetes
weight above the healthy range
non Anglo-European ethnicity
being an older mum.

Weight is the major risk factor that can be changed. But in some cases, gestational diabetes may develop without any of these risk factors. Rates of gestational diabetes in Australia have approximately doubled in the last decade. Increased testing for gestational diabetes, changing population characteristics, and higher rates of overweight and obesity may have contributed to this. There are likely to be other factors we do not fully understand. >> Read More Source: The Conversation

By Allison Sigmund, Sue Lynn Lau, Susan Hendon

Sexual health

Victorian Assisted Reproductive Treatment Authority (VARTA)

Clinical Articles

The Importance of Preconception Health for Fertility and a Child’s Future

Fertility Week 2018 starts on October 15. This year’s message, Healthy You, Healthy Baby encourages men and women to consider their health before conception to improve their chance of conceiving, and to do their best for their baby’s future health. It has been known for some time that the general environment of a uterus can cause epigenetic changes to a fetus, but there is now growing evidence that the health of both parents before and at the time of conception influences their chance of conceiving and the short and long-term health of their child. The environment where eggs and sperm mature and the composition of the fluid in the fallopian tube when fertilisation takes place are affected by parents’ general health. So, in addition to the genetic material parents contribute to their children, the health of their eggs and sperm health at the time of maturation and conception has lasting effects on the expression of the genes and the health of the future child. Obesity, smoking, environmental toxins, alcohol, drugs, lack of physical activity and poor nutrition all pose risks to the health of egg and sperm and consequently to the health of a future child. Chronic health conditions such as diabetes and hypertension can also adversely affect gamete health.

Why promoting preconception health in primary health care is important

Whether they are actively trying for a baby or not, people of reproductive age can potentially conceive any time. This is why preconception health messages need to be integrated into primary health care and discussed opportunistically with women and men of reproductive age whenever possible.

Screening for pregnancy intention

A condition for preconception health optimisation is that the pregnancy is planned. To reduce the risk of unintended pregnancy, the ‘Guidelines for preventive activities in general practice’ recommend screening for pregnancy intention in primary health care settings. A promising method for assessing the risk of unintended pregnancy and giving prospective parents the opportunity to optimise their preconception health is the One Key Question® (OKQ) initiative developed by the Oregon Foundation for Reproductive Health. It proposes that women are asked ‘Would you like to become pregnant in the next year?’ as a routine part of primary health care to identify the reproductive health services they need to either avoid pregnancy or increase the chances of a successful one. This non-judgemental approach allows practitioners to provide advice about reliable contraception if the answer is ‘no’ and information about preconception health if the answer is ‘yes’ or ‘maybe’.

Providing preconception health information and care

While a 15-minute consultation will not allow in depth discussions about contraception or preconception health, directing women to reliable sources of information and inviting them to make a time to come back to discuss their reproductive health needs in light of their pregnancy intentions might increase awareness of the importance of preconception health optimisation. Considering the mounting evidence about the role of paternal preconception health for fertility and the health of offspring, men also need to be made aware of the importance of being in the best possible shape in preparation for fatherhood. Directing men to accessible and reliable sources of information about male reproductive health can improve awareness about how they can contribute to the long-term health of their children.

Quality resources

Your Fertility is the Commonwealth Government funded national fertility health promotion program that improves awareness among people of reproductive age and health and education professionals about potentially modifiable factors that affect fertility and reproductive outcomes. A media campaign planned for Fertility Week will encourage men and women to seek the information they need from their GP. The Your Fertility website, www.yourfertility.org.au is designed to assist time-poor practitioners to direct their patients through evidence-based, up-to-date, accessible information about all aspects of female and male reproductive health. Resources on the Fertility Week page include videos from fertility experts, facts sheets and messages tailored for both men and women. Short videos produced for health professionals feature Dr Magdalena Simonis, GP, and Associate Professor Kate Stern, fertility specialist, who both describe their approaches to raising lifestyle issues and fertility with male and female patients of reproductive age. The RACGP’s preconception care checklist for practitioners is available from www.racgp.org.au/AJGP/2018/July/Preconception-care Visit the Your Fertility website content, fact sheets for health professionals and patients help promote the important messages about how healthy parents make heathy babies. Visit the Your Fertility Website View the Preconception Care Checklist

By Victorian Assisted Reproductive Treatment Authority (VARTA)

Psychiatry

Clinical Articles

New Autism Guidelines Aim to Improve Diagnostics and Access to Services

New Australian autism guidelines, released today, aim to provide a nationally consistent and rigorous standard for how children and adults are assessed and diagnosed with autism, bringing to an end the different processes that currently exist across the country. There is no established biological marker for all people on the autism spectrum, so diagnosis is not a straightforward task. A diagnosis is based on a clinical judgement of whether a person has autism symptoms, such as social and communication difficulties, and repetitive behaviours and restricted interests. This is an inherently subjective task that depends on the skill and experience of the clinician. This judgement is made even more difficult by the wide variability in symptoms, and the considerable overlap with a range of other developmental conditions such as attention deficit/hyperactivity disorder (ADHD), intellectual disability, and developmental language disorder. Further complicating autism diagnosis in Australia is the lack of consistent diagnostic practices both within and between states and territories. This leads to patchy and inconsistent rules around who can access public support services, and the types of services that are available. It is not uncommon in Australia for a child to receive a diagnosis in the preschool years via the health system, for instance, but then require a further diagnostic assessment when they enter the education system. This is a bewildering situation that has a significant impact on the finite financial and emotional resources of families and the state. The new guidelines aim to address these inconsistencies and help people with autism and their families better navigate state-based support services. It also brings them into line with the principles of the National Disability Insurance Scheme (NDIS), which seeks to determine support based on need rather than just a diagnosis.

National guidelines

In June 2016, the National Disability Insurance Agency (NDIA) and the Cooperative Research Centre for Living with Autism (Autism CRC), where I’m chief research officer, responded to these challenges by commissioning the development of Australia’s first national guidelines for autism assessment and diagnosis. We undertook a two-year project that included wide-ranging consultation and extensive research to assess the evidence. The guidelines do not define what behaviours an individual must show to be diagnosed with autism. These are already presented in international manuals, such as the American Psychiatric Association’s Diagnostic and Statistical Manual (DSM-5) and the World Health Organisation’s International Classification of Diseases (ICD-11). What the new guidelines provide is a detailed description of the information that needs to be collected during a clinical assessment and how this information can be used to inform the ongoing support of that person, including through a diagnosis of autism. The guidelines include 70 recommendations describing the optimal process for the assessment and diagnosis of autism in Australia.

Understanding strengths and challenges

A diagnostic assessment is not simply about determining whether a person does or doesn’t meet criteria for autism. Of equal importance is gaining an understanding about the key strengths, challenges and needs of the person. This will inform their future clinical care and how services are delivered. In essence, optimal clinical care is not just about asking “what” diagnosis an individual may have, but also understanding “who” they are and what’s important to their quality of life. We know diagnosis of autism alone is not a sound basis on which to make decisions about eligibility for support services such as the NDIS and state-based health, education and social support systems. Some people who meet the diagnostic criteria for autism will have minimal support needs, while other individuals will have significant and urgent needs for support and treatment services but will not meet diagnostic criteria for autism at the time of assessment. Some people may have an intellectual disability, for example, but not show the full range of behaviours that we use to diagnose autism. Others may present with the latter, but not the former. In the context of neurodevelopmental conditions such as autism, it is crucial that a persons’s needs – not the presence or absence of a diagnostic label – are used to determine eligibility and prioritisation of access to support services.

What may influence an autism assessment?

The guidelines also detail individual characteristics that may influence the presentation of autism symptoms. Gender is one key characteristic. Males are more commonly diagnosed with autism than females. But there is increasing evidence that autism behaviours may be different in males and females. Females may be better able to “camouflage” their symptoms by using compensatory strategies to “manage” communication and social difficulties. It is similarly important to consider the age of the person being assessed, because the presentation of autism symptoms changes during life. The guidelines provide information on how gender and age affect the behavioural symptoms of autism. This will ensure clinicians understand the full breadth of autistic behaviours and can perform an accurate assessment. The next step is for all clinicians and autism service providers across Australia to adopt and implement the guidelines. This will ensure every child and adult with autism can receive the optimal care and support.

By Prof Andrew Whitehouse

Gastroenterology

Clinical Articles

Are We Missing Chronic Pancreatitis? Does it Matter?

The answer to both these questions is yes according to Dr Darren Pavey, gastroenterologist and senior lecturer at the University of NSW. Speaking at the Healthed General Practice Education seminar in Sydney recently, Dr Pavey said there was good international research suggesting that many cases of chronic pancreatitis were going undiagnosed and the condition was far more prevalent than previously recognised. Overseas studies including cohorts of randomly selected adult patients suggest a prevalence of between 6-12%, with the condition being more likely among patients with recent onset type 2 diabetes, excess alcohol intake, smokers and those over 40 years of age, he said. And in response to the question of whether it is important to diagnose this condition, Dr Pavey said chronic pancreatitis not only caused immediate symptoms usually including pain, diarrhoea and weight loss but commonly had longer-term consequences such as pancreatic exocrine insufficiency (where there is less than 10% pancreatic function) and an increased risk of diabetes, malnutrition and even pancreatic cancer. Certainly, an incentive to diagnose and treat earlier rather than later. Part of the challenge in recognising the condition is that the classic triad of symptoms, namely abdominal pain, diarrhoea and weight loss are common to a variety of medical conditions including IBD and IBS. What’s more, abdominal pain, which many doctors would have thought had to be present with pancreatitis does not always occur in chronic pancreatitis especially when it is idiopathic which is the more common variety of chronic pancreatitis. In fact, pain is only present in about half the cases of idiopathic chronic pancreatitis. Idiopathic pancreatitis constitute 55% of all cases, the other 45% being alcohol-related. Abdominal pain tends to be a more consistent feature of alcoholic chronic pancreatitis. So if you have a patient in the right age group (about 40 to 60 years), who has chronic diarrhoea, weight loss and maybe abdominal pain and you suspect they might have chronic pancreatitis what do you do? The most common screening test for chronic pancreatitis is now a faecal elastase-1 stool test, requiring a single formed stool sample, said Dr Pavey. The test has a high specificity and sensitivity (both over 90%) and is readily available to Australian GPs, although it does not attract a Medicare rebate and costs approximately $60. The test is positive if the concentration of faecal elastase is less than 200mcg/g. In terms of imaging, CT is usually the option of first choice with signs of calcification and atrophy being pathognomonic of significant chronic pancreatitis. Aside from the need to stop drinking and smoking, treatment revolves around replacement of the pancreatic enzymes, which is available as a capsule taken orally (Creon). The deficiency of these enzymes is the chief cause of the diarrhoea, malabsorption, and weight loss so replacing them not only alleviates the symptoms but will also help prevent some of significant sequelae associated with this ongoing condition. Interestingly, a study of patients newly diagnosed with pancreatic cancer, showed that 66% had pancreatic exocrine insufficiency at diagnosis, and after two months this prevalence grew to 93% Dr Pavey advises starting patients with known chronic pancreatitis on 25,000 lipase units (Creon) with every meal and 10,000 units with every snack, and recommends patients eat six smaller meals during the day rather than three larger meals. This replacement therapy would then be titrated up to 40,000 units with a meal and 25,000 units for a snack. For those whose need was greater, replacement could even be increased to 80,000 units per meal. There was no need to put patients on a reduced fat diet when they were on pancreatic enzyme replacement therapy however they often had a highly acidic upper gastrointestinal environment and required acid suppression treatment. In conclusion, Dr Pavey advises clinicians to have a high index of suspicion for this poorly-recognised but important condition. “[Doctors] should be aware of the problem of underdiagnosing this condition and have a low threshold for checking faecal elastase and assessing pancreatic insufficiency,” he said.

By Dr Linda Calabresi

Pathology

Clinical Articles

Infection Risk in Asplenia and Hyposplenism

It is estimated that up to 25,000 Australians are affected by asplenia or hyposplenism.¹ Many are unaware of the fact, and its potential consequences. The spleen plays an important role in immune function, in particular the prevention of infection due to some specific organisms (Table 1).

Infection Risk

Infection is a relatively common occurrence in those without a functioning spleen. Overwhelming post-splenectomy infection (OPSI), occurs in up to 5% of asplenic patients and has a mortality rate of over 50%. The risk is particularly high in children aged under five, and in the first three years post-splenectomy. However, the risk is lifelong.¹

Organisms of Concern

Table 1: Organisms of Concern

Agent	Comment
Streptococcus pneumoniae	Accounts for >50% of severe infections. Vaccine available and recommended
Neiserria meningitidis	Vaccine available and recommended.
Haemophilus influenza type B	Vaccine available and recommended.
Capnocytophagia species	Oral flora in animals. Risk of acquisition after animal bites.
Bordetella holmesii	Newly recognised pathogen.
Plasmodia species (Malaria) Babesia, Ehrlichia	Potential risk for travellers. Seek pre-travel advice.

Causes of Asplenia and Hyposplenism

Asplenia maybe congenital but is more often acquired as a result of trauma or the surgical removal of the spleen due to haematological conditions, or after incidental splenic damage incurred during intra-abdominal surgery. Functional hyposplenism also confers an increased risk of infection and may occur as a result of a number of medical conditions (Table 2). Table 2: Medical conditions associated with hyposplenism

Coeliac disease

SLE

Sickle Cell disease

Rheumatoid arthritis

Malignant infiltration e.g. lymphoma

Splenic infarction or radiation

Graft versus host disease

Detection of Asplenia and Hyposplenism

The presence of Howell-Jolly bodies in a blood film may be a clue to the presence of unrecognised asplenia or hyposplenism. Other investigations that may be of assistance in suspected cases are imaging studies such as ultrasound or CT.

Prevention of Infection

Evidence suggests it is possible to significantly decrease the incidence of infection in asplenic and or hyposplenic patients. Spleen Australia has recently demonstrated a 69% reduction in serious infections in patients on their registry.² The key strategies utilised by Spleen Australia include; 1. Education

Informing patients and their families of the risk of infection, signs and symptoms of sepsis and the need to develop a management plan should these occur:
- Importance of seeking urgent medical attention if symptomatic.
- Maintaining a standby supply of antibiotics for emergency use.
Provision of advice regarding travel and other potential exposure risks e.g. animal contact.
Encouraging the wearing of a Medical Alert bracelet.

2. Provision of advice regarding appropriate antibiotic therapy (as per Therapeutic Guidelines)

Consider antibiotic prophylaxis, particular in first three years post-splenectomy (With either penicillin or roxithromycin).
Maintain a standby emergency supply of antibiotics in case of sepsis (usually Amoxil 3g).

3. Provision of current, detailed, practical guidelines for vaccination (As per Immunisation Handbook)

Pneumococcal, Meningococcal, Haemophilus influenza type B vaccines - initial course and ongoing boosters as required.
Annual influenza vaccine - to minimise the chance of post-influenza bacterial infection.

Currently, persons resident in Victoria, Queensland and Tasmania are able to register with Spleen Australia and will then receive regular newsletters and reminders when vaccines are due. It is hoped that this service will be extended to other states. See www.spleen.org.au for details.

Key Messages

Infection is a significant, life-long risk in asplenic and hyposplenic patients.
The risks can be mitigated by:
- The early recognition of the underlying condition,
- Comprehensive patient education,
- Appropriate use of use of prophylactic and empirical antibiotics, and
- Ensuring that patients receive recommended initial and ongoing vaccinations.

Spleen Australia provides an excellent range of resources and is happy to assist in the management of these patients if required.

References

Spleen Australia. Welcome to Spleen Australia: a clinical service and registry for people with a non-functioning spleen. Melbourne VIC: Diabetes Australia. Available from: www.spleen.org.au
Arnott A, Jones P, Franklin LJ, Spelman D, Leder K, Cheng AC. A Registry for Patients With Asplenia/Hyposplenism Reduces the Risk of Infections With Encapsulated Organisms. Clin Infect Dis. 2018 Aug 1; 67(4): 557-61. Available from: https://doi.org/10.1093/cid/ciy141

General Practice Pathology is a new regular column each authored by an Australian expert pathologist on a topic of particular relevance and interest to practising GPs. The authors provide this editorial, free of charge as part of an educational initiative developed and coordinated by Sonic Pathology.

By Dr Alistair McGregor, Sullivan Nicolaides Pathology

Drugs and devices

Clinical Articles

The Vit D Story Now a Fairytale

It wasn’t that long ago that vitamin D appeared to be the panacea for everything from preventing MS to reducing the risk of diabetes. But the one area where we thought the benefit of this vitamin was not up for debate was bone health. It has been proven - lack of vitamin D causes rickets. It has been proven that vitamin D is important in bone metabolism and turnover. And it has been proven the people with low bone density are more likely to experience fractures. Therefore add vitamin D and improve bones, right? Wrong! The latest meta-analysis of more than 80 randomised controlled trials shows that vitamin D supplementation does not prevent fractures or falls, and does not have any consistently clinically relevant effects on bone mineral density. This comes as a bit of a surprise, to say the least. According to the systematic review, vitamin D had no effect on total fractures, hip fractures, or falls among the 53,000 participants in the pooled analysis. And it didn’t matter if higher or lower doses of vitamin D were used, the New Zealand researchers reported in The Lancet. In looking for a reason for the lack of an effect from supplementation, previous explanations such as baseline 25OHD of trial participants being too high, or the supplement dose being too low, or the trial being done in the wrong population just don’t hold water. The sheer number and variety of trials included in this meta-analysis has meant all of these possible confounders have been accounted for. “The trials we included have a broad range of study designs and populations, but there are consistently neutral results for all endpoints, including the surrogate endpoint of bone mineral density,” they said. Consequently, the researchers said future trials were unlikely to alter these conclusions. “There is little justification to use Vitamin D supplements to maintain or improve musculoskeletal health,” they stated. And while they acknowledge the clear exception to this is in the case of the prevention or treatment of rickets and osteomalacia, in general clinical guidelines should not be recommending vitamin D supplementation for bone health. The conclusion appears quite emphatic and definitive, and it is supported in an accompanying commentary by a leading US endocrinologist. “The authors should be complimented on an important updated analysis on musculoskeletal health,” said Dr Chris Gallagher from Creighton University Medical Centre, Omaha in the US. But he suggests many Vitamin D supporters will still be flying the flag for supplementation, pointing to the multiple potential non-bony benefits. “Within three years, we might have that answer because there are approximately 100,000 participants currently enrolled in randomised, placebo-controlled trials of vitamin D supplementation,” he said. “I look forward to those studies giving us the last word on vitamin D.”

References

Bolland MJ, Grey A, Avenell A. Effects of vitamin D supplementation on musculoskeletal health: a systematic review, meta-analysis, and trial sequential analysis. Lancet Diabetes Endocrinol. 2018 Oct 4. Available from: http://dx.doi.org/10.1016/S2213-8587(18)30265-1 [epub ahead of print] Gallagher JC. Vitamin D and bone density, fractures, and falls: the end of the story? Lancet Diabetes Endocrinol. 2018 Oct 4. Available from: http://dx.doi.org/10.1016/S2213-8587(18)30269-9 [epub ahead of print]

By Dr Linda Calabresi

Gastroenterology

Clinical Articles

The Gut Microbiome – Fad or The Future?

Which bacteria are colonising your gut is becoming increasingly important, Australian researchers say. More and more evidence is suggesting the gut microbiota has a significant role in both the cause and the cure of a wide range of gastrointestinal and hepatic diseases and conditions. According to a review in The Medical Journal of Australia, research shows that particular types of bacteria colonising the gut have been associated the development of inflammatory bowel disease (IBD), metabolic syndrome, non-alcoholic fatty liver disease (NAFLD), non-alcoholic steato-hepatitis (NASH), obesity and diabetes. We know that the bowel starts to be colonised by bacteria in utero. The make-up of an individual’s gut microbiota then depends on factors such as mode of delivery, breast-feeding, diet, illness and exposure to antibiotics. By the age of three, the gut microbiota resembles that of an adult. Observational studies have suggested a strong association between alterations in the microbiota because of environmental factors, and an increased risk of diseases. For instance, IBD was very rare in traditional Chinese populations, but studies have shown exposure to Western diets and medicines from a young age has increased the prevalence of this disease. “Asian adults who migrate from countries of low prevalence to countries of high prevalence do not have an increased risk of developing IBD, but their children experience the IBD incidence of their new country of residence,” the review authors said. Stronger evidence comes from studies into the exact nature of bacteria colonising the gut. It appears both the specific bacteria and the diversity of bacteria are important in disease pathogenesis. “For example, the presence of Proteus species at the time of Crohn’s disease resection is associated with early disease recurrence, while the presence of Faecalibacterium prauznitzii is protective against recurrence,” they said. Researchers have also found significant differences in the microbiota of people who develop severe alcoholic hepatitis and those who maintain normal hepatic function despite drinking the same amount of alcohol. Most importantly in the investigation of the role of the gut microbiota, is the emerging evidence that by altering the bacterial colonies in the gut we can alter the course of the disease. The classic example of this, of course, was the discovery of Helicobacter Pylori as the cause of peptic ulcer disease with treatment of this, dramatically changing health outcomes. But since then a lot of the research focus has been on faecal microbiota transplants (or poo transplants as they are commonly known). Mice studies have shown that a mouse will become fat if given a transplant of faecal bacteria from a fat donor mouse. Similarly, a similar result has been shown in a single trial of FMT from lean to obese humans, lowering triglyceride levels and increasing insulin sensitivity. FMT has also been shown to be an effective therapy for recurrent C.difficile infection and in active ulcerative colitis. And while the application of FMT as a treatment continues to be explored, investigators are also looking at how the microbiota can be changed through dietary means and how this can be used therapeutically. While probiotics have not been shown to be effective in the majority of inflammatory diseases, an anti-inflammatory diet combined with liquid formulated enteral nutrition has shown some success in Crohn’s disease. In short, the review authors suggest that the current interest in the gut microbiome is justified and has the potential to provide important therapeutic options in the future. “Microbial manipulation is an effective therapy, likely to have broadening implications,” they concluded. Reference White LS, Van den Bogaerde J & Kamm M. The gut microbiota: cause and cure of gut diseases. Med J Aust. 2018 Oct 1; 209(7): 312-16. Available from: https://www.mja.com.au/journal/2018/209/7/gut-microbiota-cause-and-cure-gut-diseases doi: 10.5694/mja17.01067

By Dr Linda Calabresi

Immunology and allergy

Clinical Articles

Vaccinating the Immunosuppressed – Who, What and When

Vaccination in immunosuppressed adult patients has many facets and can be challenging for GPs who don’t deal with these cases regularly. But there are a few key considerations that can help guide clinicians, says Associate Professor Michael Woodward, Melbourne-based geriatrician, writer, researcher and passionate advocate for health promotion. Firstly, not all immunosuppression is equal. It is important to ascertain the degree of immunosuppression, as some people may be being unnecessarily denied vaccines because they are taking medication that can suppress the immune system but only at higher doses or in different formulations. “For instance, someone who is on inhaled corticosteroids for their asthma or on low dose (less than 20mg) prednisolone daily for just a few weeks is not significantly immunosuppressed and can be vaccinated in the same way as other people,” said Professor Woodward in an interview following his presentation at Healthed’s recent Annual Women's and Children’s Health Update in Perth. However, those on higher doses of steroids or on steroids more long-term, as well as those people who have conditions associated with immunosuppression such as haematological malignancy do need special consideration when it comes to vaccination. Most importantly, live vaccines are not to be given to this group. This includes the new herpes zoster vaccine (Zostavax), which absolutely contraindicated in severely immunocompromised patients. The consequences of inadvertently administering this vaccine to an immunosuppressed patient hit the headlines some months ago, highlighting the importance of this guideline. The other question often asked is whether patients who are known to be immunosuppressed, and therefore at greater risk of significant infections actually need more or stronger doses of the vaccines they are able to have. In some cases that is a very real and worthwhile consideration if you want to achieve the objective of immunoprotection, Professor Woodward said. For example, you might consider giving an immunosuppressed patient the pneumococcal vaccine (Prevenar 13) as opposed to the polysaccharide pneumococcal vaccine (Pneumovax 23). “The conjugate vaccine is generally slightly more likely to produce an immune response [than the polysaccharide vaccine],” he said. The other scenario where GPs might need to be considering vaccination in association with immunosuppression, is in patients who are scheduled for an elective splenectomy. The lack of a spleen is known to be associated with a reduction of the body’s ability to respond to a vaccine, so it is currently recommended that people who are about to undergo a splenectomy have the influenza, pneumococcal and the newer zoster vaccine. In addition, they should be vaccinated against H. influenza B and receive the two meningococcal vaccines currently available. All these are detailed as part of the pre-splenectomy recommendations on the spleen.org.au website, with the exception of the zoster vaccine, as the guidelines have yet to be updated. However, Professor Woodward says most health professionals in this area are advocating the inclusion of the zoster vaccine. Some of these vaccinations may also be given shortly after the removal of the spleen in cases where the splenectomy has been urgent, but this is generally not the remit of the GP. In general, the question of vaccination in the immunosuppressed patient can be complicated. It is a highly specialised area and Professor Woodward suggested, if in doubt GPs might want to seek input from a specialist in this area such as an immunologist or a rheumatologist.

By Dr Linda Calabresi

Genetics

Clinical Articles

Prenatal Screening for Chromosome Disorders

Prenatal screening for chromosome disorders by maternal serum screening, ultrasound and non-invasive prenatal tests, such as Harmony®, is an established part of reproductive care in Australia. The overall risk of chromosome disorders rises markedly with maternal age, as shown in Figure 1. (There are two exceptions: Monosomy X, also known as Turner syndrome, and microdeletions, such as 22q11.2, occur independently of maternal age). This does not mean that chromosome screening should be restricted to older mothers. Younger mothers have more babies than older mothers, and the overall outcome is that the majority of pregnancies with a serious chromosome disorder occur in mothers under 35 years of age. For this reason, screening for chromosome disorders in pregnancy should be offered to mothers of all ages. The great majority of these chromosome disorders are new abnormalities that have happened for the first time in this pregnancy. They are not inherited disorders, and genetic testing of the parents provides no information about the risk of such an abnormality. This provides another reason for offering screening for chromosome disorders to all mothers, irrespective of family history.

The frequency of single-gene disorders at birth

Chromosome disorders are not the only type of genetic condition which can affect the developing foetus. Many serious childhood disorders are due to recessive mutations that have been inherited from parents, with the parents being unaffected by these mutations. A parent who is a carrier of a recessive mutation, that is, having one normal and one abnormal copy of a gene, will not be affected by the abnormal gene. Everyone is a carrier for one or more disorders; this is of no immediate consequence and there usually is no family history of the disorder. The situation changes if both parents are carriers of mutations in the same gene located on one of the autosomes (chromosomes 1-22). The chance of their child inheriting the abnormal gene from each parent, and so developing an autosomal recessive disorder, is 25%. The situation is a little different for a woman with a recessive mutation on an X-chromosome: each of her sons is at 50% risk of inheriting the abnormal gene and being affected, and half of her daughters will be carriers. Overall, the risk of a woman who is an X-linked carrier having an affected child is approximately 25%. There are hundreds of inherited autosomal and X-linked recessive disorders that present in infancy and early childhood. These disorders are individually rare but, together, they are more common than the chromosome disorders for which prenatal screening is widely available and accepted. Further, the risk of these recessive disorders does not vary with maternal age (Figure 1). For mothers under 35 years of age, the risk of having a child with a serious childhood-onset recessive disorder is greater than the risk of having a child with a chromosome disorder.

Screening potential parents for recessive disorders

These disorders are inherited but there is usually no family history to provide a clue. Until recently, the only way of identifying a carrier of a rare recessive disorder was to diagnose the disorder in their affected child. This has now changed. It is possible to screen a couple for mutations in autosomal genes, and a woman for mutations in X-linked genes, to determine whether they are at 25% risk of having an affected child. This screening test is called ’reproductive carrier screening’. From both a technical and clinical perspective, the challenge lies in choosing which genes to analyse. A number of providers, including Sonic Genetics, offer reproductive carrier screening for mutations responsible for three common disorders: cystic fibrosis and spinal muscular atrophy (both autosomal recessive) and Fragile X syndrome (X-linked recessive). Approximately 6% of people are carriers of one or more of these conditions, and 0.6% (one in 160) couples are at 25% risk of having an affected child. Those couples who are identified as carriers can consider a variety of options, including IVF with a donor gamete, pre-implantation genetic diagnosis, prenatal diagnosis by CVS, or they may make an informed decision to accept the risk. RANZCOG recommends that couples be offered such screening. The cost of this three-gene panel is approximately $400* per person. There is no Medicare rebate for carrier screening; there are exceptions (and restrictions) for people with a documented family history of cystic fibrosis or Fragile X syndrome.

Expanded reproductive screening

If we were to screen more genes, we would identify more carriers. Sonic Genetics offers a screen of over 300 genes (autosomal and X-linked) which cause serious recessive childhood disorders. We estimate that approximately 70% of Australians are carriers for one or more conditions included in this screen and 3% (one in 30) couples are at 25% risk of having an affected child. This amounts to five times more information than is provided by the three-gene panel. This screen, the Beacon Expanded Carrier Screen, currently costs $995* per person or $1,750* for couples tested together. It is tempting to think that ‘more genes tested = more information for a couple’. This is not the case because the information provided by a carrier screen is also determined by the carrier frequency, mode of inheritance and detection rate of the assay for each gene. Some currently available screens of more than 100 genes provide less information than the three-gene screen described earlier.

Implementing reproductive screening

Before offering reproductive carrier screening to your patients, it is important to consider some of the nuances, particularly in relation to the Fragile X syndrome (some carriers will develop premature ovarian failure or a tremor/ataxia syndrome in later life) and when there is a family history of a recessive disorder (seek expert advice; do not rely on screening). It is also important to recognise that some couples will not want this carrier information – and others will demand it. Each person needs to be free to make their own decision about what information they wish to have. We provide information about the three-gene and Beacon screens for both requestors and patients on our website. Sonic Genetics also offers genetic counselling free-of-charge for couples who are identified by either of these reproductive carrier screens as being at high risk of having an affected child (see www.sonicgenetics.com.au/rcs/gc).

Conclusion

It is accepted practice that every woman is offered screening for chromosome disorders in pregnancy, irrespective of age and family history. In a similar vein, every couple should be offered reproductive carrier screening for recessive disorders, irrespective of age and family history. For women under 35 years, the risk of their child having a recessive disorder is greater than the risk of a chromosome disorder. Offering reproductive carrier screening simply represents good medical practice.

References

RANZCOG. Prenatal screening and diagnostic testing for fetal chromosomal and genetic conditions. 2018 Aug. 35 p. Available from: https://www.ranzcog.edu.au/RANZCOG_SITE/media/RANZCOG-MEDIA/Women%27s%20Health/Statement%20and%20guidelines/Clinical-Obstetrics/Prenatal-screening.pdf?ext=.pdf Archibald AD, Smith MJ, Burgess T, Scarff KL, Elliott J, Hunt CE, et al. Reproductive genetic carrier screening for cystic fibrosis, fragile X syndrome, and spinal muscular atrophy in Australia: outcomes of 12,000 tests. Genet Med. 2018; 20(5): 513-523 Available from https://www.ncbi.nlm.nih.gov/pubmed/29261177 doi:10.1038/gim.2017.134. Sonic Genetics [Internet]. c2015. Reproductive Carrier Screening; 2018. Available from: www.sonicgenetics.com.au/rcs General Practice Pathology is a new regular column each authored by an Australian expert pathologist on a topic of particular relevance and interest to practising GPs. The authors provide this editorial, free of charge as part of an educational initiative developed and coordinated by Sonic Pathology.

By Sullivan Nicolaides Pathology

Bowel Cancer Screening: Who, When, How?

New NHMRC guidelines put age and family history up front and centre in determining who should be screened for bowel cancer with colonoscopy and who needs iFOBT. It has been known for some time that family history can influence the risk of developing bowel cancer, Australia’s second most common cause of cancer death. But it is also known that specific, identified genetic mutations causing conditions such as Lynch syndrome or familial adenomatous polyposis are rare, accounting for less than 5% of all bowel cancers diagnosed. At most, the researchers say, this only explains half of the reasons why family history is a risk factor for bowel cancer. “The remainder of the observed increases in familial risk could be due in part to mutations in yet to be discovered colorectal cancer susceptibility genes, polygenic factors such as single-nucleotide polymorphisms, or dietary and other lifestyle factors shared by family members,” the guideline authors said in the Medical Journal of Australia. Therefore, the researchers, led by Professor Mark Jenkins, director of the Centre for Epidemiology and Biostatistics, in the University of Melbourne’s School of Population and Global Health, analysed all the available cohort studies to determine the risk of developing colorectal cancer based on age and family history. They categorised cohorts into one of three levels of risk and this determined at what age screening would be worthwhile starting and which screening method was most appropriate. The screening guidelines exclude people with a known or suspected cancer-causing genetic syndrome, as these people require much more intensive screening and should be managed in a family cancer clinic. The majority of Australians (90%) fall into the lowest risk category, category 1, which puts their risk at age 40 of developing colorectal cancer in the next 10 years at about 0.25% (one in 400). As with most other cancers age is a risk factor, so it is unsurprising that at age 50 the risk of developing this cancer has risen to 0.9%. Screening for this category 1 group should be the two-yearly iFOBT test that is currently available via the National Bowel Screening program for adults between the ages of 50 and 74 years. Interestingly, people aged 75 and older still develop bowel cancer but there have been no studies to determine the cost-effectiveness or benefit vs risk analysis of screening in this age group which is why the program and the guideline recommendations stop at 74 years. One of the differences in these new guidelines, a revision from the previous ones published back in 2005, is that people with a first degree relative who has had or has a bowel cancer at age 55 or older are still considered at average risk (category 1). However, people with this history might consider starting the iFOBT screening at a younger age (45 years), the guideline authors suggest. Category 2 includes people with a moderately increased risk of developing colorectal cancer, 3-6 times higher than average. This will mean having a first degree relative diagnosed with a bowel cancer before the age of 55 or having two first degree relatives who developed bowel cancer at any age (or one first degree and two second degree relatives). Category 2 people are recommended to have iFOBT every two years for the decade between ages 40 and 50 and then switch to five yearly colonoscopies until the age of 75. Finally, the high risk, category 3 is for all those patients without a genetic syndrome whose family history is even stronger than those people in category 2. Their risk is between 7-10 times higher than average. This includes people with at least three first-degree relatives who have been diagnosed with colorectal cancer at any age or people who have multiple relatives with the cancer including at least one diagnosed before aged 55. These high-risk people need to start screening earlier, with the guidelines recommending iFOBT every two years starting at age 35 and continuing for 10 years and then having a colonoscopy every five years between the ages of 45 and 75. Of note is that the revised guidelines have deleted the reference in the previous guidelines to starting screening 10 years before the earliest age colorectal cancer was diagnosed in a first degree relative. “There have been no studies conducted to determine the utility of beginning screening 10 years before the earliest diagnosis in the family, which was a recommendation in the 2005 guidelines and, therefore, it is not included in these guidelines,” they said. The new guidelines aim not only to more strongly define risk based on the latest evidence, but also to determine the most appropriate screening method based on that risk, taking into consideration cost-effectiveness and rationalisation of available services, in particular, colonoscopies. Reference Jenkins MA, Ouakrim DA, Boussioutas A, Hopper JL, Ee HC, Emery JD, et al. Revised Australian national guidelines for colorectal cancer screening: family history. Med J Aust. 2018 Oct 29. doi: 10.5694/mja18.00142. [epub ahead of print]

By Dr Linda Calabresi

Clinical Articles

Oncology

Changes to Medicare for Home Sleep Study Testing