84 J. Endocrinol. Invest. 26: 84-87, 2003 ABSTRACT. The case of a 15-yr-old boy with C11 hydroxylase deficiency congenital adrenal hyper- plasia is reported who was diagnosed and treat- ed as true precocious puberty at the age of 2 yr because of virilization and bilateral testicular en- largement. He later developed hyperpigmenta- tion, hypertension and short stature and because of an increase in testes size he underwent testicu- lar biopsy with the assumption of Leydig cell tu- mor. With the intake of glucocorticoids his testes size, hypertension and hyperpigmentation im- proved markedly. We could find only 6 such cases in the literature and have reviewed their clinical and laboratory data. All patients showed the pic- ture of virilization with hypertension. Leydig cell tumor was proposed as the differential diagnosi s in all cases except ours. Ultrasonography was able to show testicular adrenal-like tissue in all those in whom the procedure was undertaken. In the 5 pa- tients of whom we could find enough data, 1 re- sponded partially and 4 responded markedly to corticosteroid therapy with shrinkage of testicular tumors. We conclude that clinical findings and US are very important in the early diagnosis of these patients and with adequate treatment most cases show shrinkage in testicular tumors. (J. Endocrinol. Invest. 26: 84-87, 2003) © 2003, Editrice Kurtis INTRODUCTION Testicular enlargement due to the overgrowth of adrenal remnant tissue in C11 hydroxylase deficien- cy (C11 HD) congenital adrenal hyperplasia (CAH) is very rare. To the best of our knowledge only 6 cas- es have been reported in the literature (1-5). The enlarged firm testes, which are almost always due to non-compliance with treatment may be mis- interpreted as Leydig cell tumor and, while the his- tologic differentiation is not always easy, unneces- sary orchiectomy may be undertaken. We here present a new case with review of the clini- cal and laboratory data of the 6 previously reported cases. In the present case, enlargement of the testes led to the diagnosis of true precocious puberty and postponed the logical treatment of the patient. PRESENTATION OF THE CASE A 15-yr-old boy was referred to the Department of Endocrinology and Metabolism at the Taleghani Teaching Hospital, Tehran, Iran, for the evaluation of short stature, hypertension and sexual precocity. The patient’s problem had begun at the age of 2 yr, when his parents noted polyphagia, abnormal- ly high growth rate, increase in penile size and growth of pubic hair. The information in the pa- tient’s file revealed the following: height 129 cm (>97 percentile), weight 30 kg (>97 percentile), in- creased penile size and bilateral testicular enlarge- ment. FSH was 1 mIU/ml (normal values <3), LH was 8 mIU/ml (normal values <3), PRL was 15 ng/ml (normal values <15) and T was 450 ng/dl (normal values 5-20). Bone age was 11 yr and pituitary CT scan was reported as normal. The case was diagnosed as true precocious puber- ty and treatment was begun with medroxyproge- strone, 100 mg im injection every 2 weeks. The pa- tient discontinued the medication after a short pe- riod and did not seek medical attention until the age of 11 yr, when he developed recurrent attacks Key-words: Adrenal rest tumor, C11 hydroxylase, congenital adrenal hy- perplasia, bilateral testicular enlargement, precocious puberty. Correspondence: Dr. Ali A.M. Ghazi, P.O. Box 19395-4763, Tehran, Iran. E-mail: ghazi@erc-iran.com Accepted April 23, 2002. CASE REPORT Bilateral te s ticular enlarge ment due to adrenal re mnant in a patient with C11 hydroxyla s e deficiency congenital adrenal hyperpla s ia A.A.M. Ghazi*, F. Hadayegh*, G. Khakpour**, F. Azizi*, and J.C. Melby*** *Endocrine Research Center, **Department of Urology, Shaheed Beheshti University of Medical Sciences, Tehran, Iran, ***Department of Medicine, Boston University Medical Center, Boston, USA