The real-time pelvic sonograms of 32 girls under 8 years old with true isosexual precocity (23 cases), pseudosexual precocity (four cases), premature adrenarche (four cases), and an undetermined problem (one case) were evaluated retrospectively for ovarian volume and presence and size of cysts. Sonographic findings were compared to those of 181 age-matched controls to determine the best sonographic indicator of precocious puberty. Ovarian volume was 4.6 cm3 in girls with true isosexual precocity, 4.1 cm3 in girls with pseudosexual precocity, and less than 1 cm3 in the other patients as well as in the control population. Ovarian enlargement was bilateral in true precocity and unilateral in pseudosexual precocity. Of the 181 subjects in the control group, 96 (53%) had ovarian cysts, almost all of which were small (less than 9 mm in diameter). Ovarian cysts occurred in 22 of 32 patients (69%) with precocity. The cysts generally were smaller than 9 mm in true isosexual precocity and larger than 9 mm in pseudosexual precocity. In conclusion, small ovarian cysts are not specific to precocious puberty and its various subtypes. Bilateral ovarian enlargement appears to be a reliable indicator of true isosexual puberty, whereas unilateral ovarian enlargement in combination with macrocysts is suggestive of pseudosexual precocity.

Many of the distinguishing features of leprechaunism (Donohue's syndrome) suggest abnormalities of endocrine regulation. Prominent genitalia, rugation of the labioscrotal folds, polycystic ovaries, and precocious puberty are associated with leprechaunism,1 and these characteristics indicate possible pathology in the hypothalamic-pituitary-gonadal axis. In the few reported cases of leprechaunism in which this area has been evaluated, no consistent biochemical abnormalities have emerged. A review by Elders et al1 describes three cases in which baseline gonadotropin levels were normal, and gonadotropin-releasing hormone response in the one patient tested was normal.1 Szilagyi et al, however, reported a single case in which baseline luteinizing hormone was extremely elevated (385 mIU/mL) and did not respond to luteinizing hormone-releasing hormone, whereas baseline follicle-stimulating hormone was slightly elevated (13.0 mIU/mL) and had an exaggerated response to luteinizing hormone-releasing hormone.2