J Pediatr Adolesc Gynecol (2003) 16:143–145 Clinical Pathological Correlation Isolated Clitoral Hypertrophy Eduardo Lara-Torre, MD and Sari Kives, MD Division of Pediatric and Adolescent Gynecology, Department of Obstetrics, Gynecology and Women’s Health, University of Louisville Medical School, Louisville, Kentucky, USA Case Presentation A 17-yr-old Caucasian female presented to the office for evaluation of clitoral enlargement detected at birth. As the clitoromegaly persisted, at age 4 she underwent hormonal evaluation at the recommendation of her primary care physician. The patient reported these tests to be normal. A bone age was also performed and reported to be within normal limits. She returned to the office at age 17 for further evaluation and manage- ment of her clitoromegaly. Menarche occurred at age 15 and thelarche a year prior. Her menses were irregular, occurring every 30 to 90 days. She denied any family, medical, or surgical history and was not taking any medications or drugs. Her mother’s pregnancy was uncomplicated; there was no history of exposure to any medications in utero. She denied any excess hair growth, deepening of the voice, or significant acne. Initial Differential Diagnosis Clitoral enlargement usually occurs with other signs of virilization, including hirsutism, acne, and change in voice tone. When patients present at birth with this condition, the differential diagnosis should include both hormonal and nonhormonal causes of virilization. Fetuses exposed to maternal hormones, either external (testosterone, large doses of progesterone or danazol) or from maternal sources (androgenic tumor), could predispose the female infant to virilization at birth. In general, these changes do not progress but cosmetic surgery is often needed to correct the signs of andro- genization. This patient denied any history of maternal drug exposure during pregnancy and her mother did Eduardo Lara-Torre, MD, Lecturer, Department of Obstetrics, Gynecology and Women’s Health, University of Louisville School of Medicine, 550 South Jackson Street, Louisville, KY 40202; E-mail: elaratorre@yahoo.com  2003 North American Society for Pediatric and Adolescent Gynecology 1083-3188/03/$22.00 Published by Elsevier Inc. doi:10.1016/S1083-3188(03)00039-1 not have a history of tumor, making an endogenous source of androgens an unlikely cause. Other hormonal causes of virilization include enzyme deficiencies in the steroidgenesis pathway, which in turn increase the precursors to form andro- gens. The most common enzyme deficiency is congeni- tal adrenal hyperplasia (CAH). An androgen-producing tumor could also explain increased androgen produc- tion and result in virilization. Nonhormonal causes of ambiguous genitalia also should be included in the differential diagnosis and include gonadal dysgenesis and both true and pseudo-hermaphroditism (insensitiv- ity syndromes). 1 Occasionally, isolated tumors of the clitoris like neurofibromatosis have also been reported to present with clitoral enlargement. 2 In this patient, only true and pseudo-hermaphroditism can be ruled out because these patients lack mu ¨ llerian structures and menses. 1 Further physical examination and labora- tory testing is required. Physical Examination The physical examination revealed a well-nourished female, height 1.67 m and wt 65.2 kg with a blood pres- sure of 118/72 mm Hg. Her skin appeared normal, without acne or hirsutism. She had no thyromegaly and her heart and lung exams were normal. She had Tanner IV breasts without masses. Her abdominal exam was normal. Her gynecological exam revealed Tanner V pubic hair in a female distribution; the clitoris was 15 mm in length, with a normal vaginal opening, a normal-appearing hymen, and a small cervix and uterus. The adnexa were nonpalpable. Her neurological exam was grossly intact. Clinical Assessment The clinical diagnosis to this point is still not evident. The presence of clitoromegaly since birth and no other signs of virilization suggest either a primary clitoral entity or an incomplete virilizing syndrome. Although