MON-474 Coexistence of Thyroid Dysgenesis and Premature Ovarian Failure: A Case Report

Background. Congenital hypothyroidism (CH) secondary to thyroid dysgenesis is rare. It may present with ascites and short stature. Primary ovarian failure (POF) is most commonly associated with autoimmune thyroid diseases(1). However, there is no report of the association of POF with congenital hypothyroidism. Clinical case. A 30 year old female presented with increasing abdominal girth, short stature and arrest of menstruation at 27 years old. Newborn screening was not done. Developmental milestones were at par. She had a low timber voice and was slow to respond. Her skin was rough and dry. Her hair was sparse, and she had thin eyebrows. Her tongue was not enlarged. Her abdomen was globular with a positive fluid wave test and shifting dullness. Initial tests indicated a hypothyroid state: elevated TSH (50.40 IU/mL, N=0.35-4.94 IU/mL), low FT4 (0 pmol/L, N=12-22 pmol/L). Ultrasound of the thyroid suggests thyroid dysgenesis (small right thyroid gland measuring 1.4 x 0.2 x 0.4 cm and an absent left thyroid gland). Karyotyping was 46, XX and insulin growth factor 1 was normal. Unexpectedly, further tests were consistent with a concomitant primary ovarian failure: low estradiol (5 pg/mL, N=12.4-233 pg/mL), high FSH (112.7 mIU/mL, N=3.5-12.5 mIU/mL) and LH (61.9 mIU/mL, N = 2.4-12.6 mIU/mL). Chest radiography showed left pleural effusion. Abdominal CT scan showed marked ascites with normal reproductive organs. Anti-TPO antibodies were normal (4.87 IU/mL, N=0-25 IU/mL). The patient was treated with Levothyroxine 50 mcg daily then gradually increased to 100 mcg daily. She was given Spironolactone 50 mg daily and paracentesis was also done to address ascites. The patient had improvement of symptoms after a month of treatment. However, the etiology of POF remains to be further elucidated. Conclusion. This case report emphasizes the importance of the early detection of congenital hypothyroidism through newborn screening. Severe hypothyroidism is rarely seen due to the wide availability of the TSH assay and its diagnosis should instigate further work-up for its etiology. Concomitant premature ovarian failure in the absence of an autoimmune thyroid disorder should prompt further investigation for another etiology since premature ovarian failure is not commonly associated with congenital hypothyroidism. Reference: (1) Ayesha, Jha V, Goswami D. Premature Ovarian Failure: An Association with Autoimmune Diseases. J Clin Diagn Res. 2016;10(10):QC10-QC12.