5α-Reductase deficiency in patients with micropenis
Tóm tắt
The enzyme 5α-reductase (5αR), by virtue of its peripheral 5α-reduction of testosterone (T) to dihydrotestosterone (DHT), is believed to play a major role in the differentiation and the subsequent growth of the penis. However, recent studies have reported 5αR deficiency (5αRD) in patients with isolated micropenis and hypothesized that 5αRD is not invariably associated with genital ambiguity. In Egypt, 5αRD has been reported frequently among intersex patients. The aim of this study was to assess the role of 5αRD in the development of micropenis among Egyptian patients with abnormal sexual development. The study included 29 patients who were categorized into three groups (isolated micropenis, 9 patients; microphallus with genital ambiguity, 11 patients; genital ambiguity with normal-sized phallus, 9 patients). Activity of 5αR was assessed by estimating T/DHT ratios in the basal state in pubertal subjects and following human chorionic gonadotropin (HCG) stimulation test in prepubertals. The results showed that the incidence of 5αRD was much higher in cases of ambiguous genitalia with micropenis (5 families out of 10, 50%) than in those with isolated microphallus (1/9, 11·1%) or those with ambiguous genitalia and normal-sized phallus (1/8, 12.5%). In conclusion, the study showed that isolated micropenis is a heterogeneous disorder and that 5αRD, despite its relative prevalence in Egypt, has a minimal role in the aetiology. On the other hand, 5αRD seems to correlate with penile length in intersex cases.
Tài liệu tham khảo
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