Endocrine Abstracts

JOINT1370

Background: MEN2B syndrome, due to pathogenic M918T variant in the RET proto-oncogene, carries very high morbidity and mortality with >20% of patients deceased by 25 years of age. Larger cohort studies have demonstrated that thyroidectomy performed <1 year of age drastically changes morbidity and likely mortality. However, identifying these children is clinically extremely difficult due to the constellation of non-specific gastrointestinal, musculoskeletal and endocrine symptoms, which results in the mean age of diagnosis ~13 years of age by which time medullary thyroid carcinoma has metastasised.

Aims: We advocate that including the M918T variant in RET gene in universal newborn screening programs and careful exclusion of intestinal ganglioneuromatosis on histopathology is the only way to enable earlier identification of affected children, which will improve clinical outcomes and provide an opportunity for thyroidectomy within the first year of life.

Results: We present a 5-patient case series with excellent clinical photography and histopathology images, including subglottic mucosal ganglioneuromatosis which has not previously been described.

Conclusion: We highlight that there are unique clinical features identifiable in the first 12 months of life of severe, persistent chronic constipation and alacrima (tearless crying) but often their significance is not recognised. There are also identifiable histopathological features of intestinal ganglioneuromatosis on gastrointestinal biopsies with adequate submucosa when the reviewing pathologist maintains a broad differential diagnosis mindset and isn’t blinkered by only excluding Hirschsprung disease.