Doctors should not routinely screen for herpes when testing for sexually transmitted infections, genetic testing should not be used to diagnose coeliac disease in most cases and radiation to treat some low-risk cancers should be reconsidered.
These are among the latest recommendations released on Thursday by NPS MedicineWise, an Australian-based organisation led by medical experts to provide doctors and patients with independent, evidence-based information.
They were developed in conjunction with medical societies, colleges and peak bodies to reflect the latest science, and to prevent unnecessary tests being ordered that may prove useless or even harmful to patients.
The Human Genetics Society of Australasia said genetic information and testing was more widely available but it was important to be aware the tests could lead to further unnecessary investigations, worry, ethical, social and legal issues. In particular, the society is warning people to not initiate testing on their own – for example through ordering tests available online.
A clinical professor with the organisation, Jack Goldblatt, said direct-to-consumer genetic testing for MTHFR and APOE genes were a particular worry.
“MTHFR is an enzyme that converts folate,” he said. “MTHFR variants are very common in the general population and folic acid supplementation has been shown to increase folate levels, regardless of MTHR status. Having a variant in the gene does not generally cause health problems.”
He said while APOE was considered a risk or susceptibility factor for Alzheimer’s disease, the test only revealed a probability. People undertaking a test for APOE also risked being falsely reassured, he added.
“If the likelihood of improved outcomes from the use of a test for the gene is extremely low, then it should not be undertaken,” he said.
“Genetic tests are best performed in a clinical setting with the provision of personalised genetic counselling and professional interpretation of tests results, for patients to understand the further implications of the results.”
Among the recommendations from the Gastroenterological Society of Australia is to not undertake genetic testing for coeliac disease. The coeliac gene can be found in one third of the population, but coeliac disease only affects about 1.4% of the population. Not everyone with the gene will develop coeliac disease.
Gastroenterologist Anne Duggan told Guardian Australia the test could be misleading and create unnecessary anxiety.
“The appropriate first-line screening test should be a serology test for the relevant antibodies, followed by an endoscopy and small bowel biopsy,” she said. “The genetic test is only useful when those tests are inconclusive.”
The NPS guidelines also recommend surveillance rather than radiation should be first discussed to manage low-risk prostate cancer. In some cases, low-risk prostate cancers left alone will never go on to cause harm to a patient during their lifetime.
Meanwhile, the Australian Chapter of Sexual Health Medicine has highlighted that herpes serology (blood testing) was not an appropriate screening test in people without herpes symptoms because it could not “accurately confirm whether the person is infected or is a transmission risk to others from asymptomatic shedding” of the virus.
“Clinicians also need to consider whether test results will influence treatment or outcomes because, if they do not, then testing is a waste of finite health resources and is not indicated,” the guideline states.
“Herpes serology tests only have good sensitivity and specificity in high prevalence populations.”
There were some situations when the test was useful, the guidelines say, such as for patients with sexual partners with genital herpes, and in cases where a woman appears to have a first episode of herpes during pregnancy.
