SUN-371 Successful Induction of Fertility with Low-Dose Dexamethasone in a Patient with Congenital Adrenal Hyperplasia and Testicular Adrenal Rest Tumor

Background Testicular adrenal rest tumors (TARTs) have been described in men with classic congenital adrenal hyperplasia (CAH) at a prevalence up to 90% and are a common cause of infertility in men with CAH. These tumors are located in the rete testis and because of their central location, can lead to mechanical obstruction, impaired blood flow and functional impairment of seminiferous tubules. TARTs have characteristics of adrenocortical cells and ACTH has been implicated in tumor growth. Previous reports have described restoration of fertility in patients with classic CAH and TARTs with administration of dexamethasone at relatively high doses of 750-1000 mcg daily (1, 2). We describe restoration of fertility in a male with classic CAH and TART with the use of lower dose dexamethasone. Case description A 28-year old male with classic CAH due to 21-hydroxylase deficiency presented to us for a follow-up visit after having been lost to follow-up for over a decade with concerns of impaired fertility. He had known bilateral TARTs, first noted at age 18. He and his wife had discontinued all forms of contraception 6 months prior to seeking care and reported a minimal coital frequency of 2-3 times/ week. His biochemical evaluation showed poor CAH control despite reported compliance with Prednisone 5 mg every morning and Fludrocortisone 50 mcg twice daily{(0800h evaluation prior to medication: 17-hydroxyprogesterone (17-OHP): 13060 ng/dL (reference: 13- 120); androstenedione (A4) 1025 ng/dl (reference: 26- 125), ACTH 866 pg/ml (reference: 5-46), plasma renin activity (PRA) 7.1 ng/ ml/h (reference: 0.6-4.3), FSH 1.7 U/L (reference: 1-11), LH 1.3 U/L (reference: 1-8 U/L) and total testosterone 473 ng/ dL (reference: 240-950). A semen analysis showed azoospermia (sperm count =0). Testicular ultrasonography (U/S) showed marked progression of total TART volume to approximately 16% of his total testicular volume (5.01 cc of 32.30 cc). Patient was switched to dexamethasone (250 mcg at bedtime) to suppress the nocturnal surge of ACTH to help decrease TART size. A follow-up U/S performed 5 months later showed a significant decrease in tumor size bilaterally. His total TART volume decreased by 90% (0.48 cc from a previous volume of 5.01 cc). Repeat semen analysis showed a sperm count of 131. In conjunction, biochemical control of CAH showed improvement with 0800h evaluation prior to medication: 17-OHP 66 ng/dL, A4 16 ng/ dL, ACTH 13.5 pg/ml, PRA 11 ng/ ml/h, FSH 5.4 U/L, LH 1 U/L and T 287 ng/dL. The patient’s wife was confirmed to be pregnant nine months after the initiation of dexamethasone and delivered a healthy full-term baby girl. Conclusion This case demonstrates that use of a long-acting glucocorticoid such as dexamethasone at doses as low as 250 mcg daily can decrease TART size and reverse male infertility. Acknowledgements This research was supported by the Intramural Research Program of the NIH.