_Discussion:
In this report we presented three patients with 5 alpha reductase deficiency who were relatives. Their clinical characteristics were reported and were those typically presented in the literature.
Infants whose external genitals are not typically male or female or their genital appearance is not compatible with their chromosomal sex are considered to have disorder of sex development or DSD1. XY DSD occurs due to insufficient androgen action. 5α reductase deficiency is one of the causes of XY DSD. This is a condition with autosomal recessive inheritance2. 5α reductase is the enzyme responsible for the conversion of testosterone to dihydrotestostrone (DHT).
Typical clinical feature of this disorder is a 46xy male with female appearance of the external genitals at birth. However, it may present as varying degrees of undervirilization in a male infant.6,7. The internal genital structures are male and mullerian structures are absent because anti mullerian hormones do act normally8. Most children with this condition are diagnosed at birth due to the atypical appearance of their external genitals but in cases that go underdiagnosed because of the typical female appearance of their genitals, the diagnosis is always made at puberty while the secondary male sexual characteristics like increased muscle mass and voice changes ensue9.
Biochemical findings that support the diagnosis of 5 α reductase deficiency are that of a normal serum testosterone value and increased ratio of serum testosterone to DHT10. Definitive diagnosis is made via DNA mutation analysis11,12.
Treatment of children with 5 α reductase deficiency depends on many factors. The most important factor is the patient’s phenotype and gender assignment at the time of diagnosis13.
Multidisciplinary team with good expertise in disorders of sex development is needed for the best management of these patients14. Issues like sex assignment and psychosocial condition of the patients and their families must be all considered. Patients who are diagnosed in the newborn period should be raised as male, because with the onset of puberty virilization will occure15. For children who are diagnosed later the condition is complex and the choice of sex assignment must be made in consultation with the child and his family14. If the decision is made that the child be raised as female then gonadectomy must be performed to minimize the risk of tumors in the testis and also prevent virilisation16and the external genitalia should be corrected surgically. Estrogen therapy for the induction of breast development and also prevention of osteoporosis is indicated in these cases.
For subjects who are raised as male or have changed their sex into male, supplemental androgen therapy is needed to improve virilization and phallic growth17.