SAT-315 Vitamin A Deficiency and Retinopathy on Long-Term Somatostatin Analogue Therapy: Case Presentation and Literature Review

Abstract Disclosure: E. Osher: None. N. Lubezky: None. R. Geva: None. D. Mirelman: None. Y. Sofer: None. L. Ben-Haim: None. Y. Goykhman: None. I. Wolf: None. Y. Greenman: None. An 86-year-old female presented with mesenteric neuroendocrine tumor (NET) Grade 1 (Ki67 <1%), in May 2021. Due to disease progression the patient underwent palliative small bowel resection, and consequently, somatostatin analog therapy was initiated. Two years later, the patient reported visual disturbances. Full-field electroretinogram revealed retinal dysfunction affecting both rod and cone photoreceptors, with severe vitamin A deficiency (<0.02µg/ml). Symptoms improved 4 days following high dose vitamin A supplementation. Vitamin A deficiency retinopathy is a vision-threatening condition that, while uncommon in developed countries, typically results from malabsorption due to bowel surgery or medication effects rather than poor nutrition. Data on the link between vitamin A deficiency in patients with NETs or endocrine disorders, treated with somatostatin analog is rare. In literature review, a cohort study of 55 patients receiving long-term somatostatin analogue therapy (>18 months), 19 patients were treated for acromegaly and 36 for neuroendocrine tumors (NETs). Of those, vitamin A deficiency was reported in 6%, causing night blindness in 2 NET patients. Risk factors included extended bowel resection and older age. Other fat-soluble vitamin deficiencies were common (K1: 63%, E: 58%, D: 28%), with 78% having at least one deficiency, and 32% showing multiple deficiencies. Conclusions: Fat-soluble vitamin deficiencies are significantly more common than previously thought in long-term somatostatin analogue users including Vitamin A. Regular monitoring and supplementation are recommended, particularly in elderly patients and those with a history of intestinal resection. Presentation: Saturday, July 12, 2025