MON-263 Graves’ Disease Presenting As Chronic Diarrhea In A Toddler

Abstract

Background: Hyperthyroidism is uncommon in the pediatric population and is particularly rare in patients less than 4 years of age with a reported incidence of 1 per 1,000,000 (1). The most common cause of hyperthyroidism in patients beyond infancy remains to be Graves’ disease, and its presentation may vary by age. We report a case of a toddler with Graves’ disease who presented with chronic diarrhea. Clinical Case: The patient is an 18 month old boy who initially presented to urgent care at the age of 16 months with diarrhea and emesis. He was diagnosed with viral gastroenteritis and sent home. He continued to have intermittent emesis and persistent diarrhea that did not improve with a change in milk formulation. He was seen by pediatric gastroenterology where GI work-up was negative. He presented to his pediatrician 2 months later for re-evaluation. His growth chart was notable for a 1.2 kilogram weight loss in 3 weeks and growth acceleration of 10.2 cm in 6 months (20.4 cm/yr). Laboratory work-up showed a suppressed TSH of <0.05 uU/ml. He was referred to pediatric endocrinology. The patient was born full term with no prenatal or perinatal complications. He had been gaining weight appropriately until about 16 months of age. He was not taking any medications or supplements. There was no family history of autoimmune, gastrointestinal, or thyroid diseases. At his initial endocrine visit, his examination was notable for normal heart rate and blood pressure, mild bilateral exophthalmos, and a prominent palpable thyroid gland. There was no lid lag, tremors, or tongue fasciculations. Reflexes were brisk. The remainder of his exam was normal. Further labs revealed free T4 >6 ng/dl, total T4 29.7 mcg/dL (normal 6-13.2), total T3 > 651 ng/dl. Thyroid stimulating immunoglobulin was >700% and thyrotropin binding inhibitor was 61% (normal <16%). The diagnosis of Graves’ disease was made and the patient was started on methimazole 5 mg daily. His symptoms improved after 1 week of starting treatment with less frequent diarrhea, and weight gain. Repeat labs demonstrated improving free T4 4.5 ng/dl (n 0.8-1.7) and total T3 420 ng/dl (n 80-200). He continues to have close follow up in our clinic. Clinical Lessons: We present the diagnosis of Graves’ disease in one of the youngest patients to be reported. Though Graves’ disease continues to be the most common cause of hyperthyroidism in toddlers, other causes should be considered in this age range. This case highlights the spectrum of the presentation of hyperthyroidism and impresses upon the provider to consider hyperthyroidism as a cause for unexplained chronic diarrhea in a young pediatric patient. Reference:(1) Ho, YH et al. A 3-year-old girl with Graves’ disease with literature review. Ann Pediatr Endocrinol Metab. 2014 Sep; 19(3): 154-158.