Abstract
BACKGROUND: Juvenile polyposis syndrome (JPS) is a rare hereditary polyposis disease frequently associated with an autosomal-dominant variant of the SMAD4 or BMPR1A gene. It often manifests with symptoms in children and adolescents and is infrequently diagnosed in asymptomatic adults. Establishing the diagnosis is important as patients with JPS have a high risk of developing gastrointestinal cancer and require genetic counselling and close routine follow-up. CASE SUMMARY: We report on the case of a 56-year-old female diagnosed with JPS after genetic testing revealed a rare variant of the BMPR1A gene BMPR1A c.1409T>C (p.Met470Thr). She was initially referred for colonoscopy by her general practitioner after testing positive on a screening faecal immunochemical test and subsequently found to have polyposis throughout the entire colorectum on her index screening colonoscopy. The patient was asymptomatic with a normal physical examination and no related medical or family history. Blood tests revealed only mild iron deficiency without anemia. To date, there has only been one other reported case of JPS with the same genetic variant. Subsequent colonoscopies were organised for complete polyp clearance and the patient was returned for surveillance follow-up. CONCLUSION: JPS patients can present with no prior symptoms or family history. Genetic testing plays an important diagnostic role guiding management.