Clinical_Rounds_in_Endocrinology_Volume_II_-_Pediatric_Endocrinology

324

53. How to differentiate between PAIS , 5 α - reductase type 2 defi ciency , and 17β -
    HSD3 defi ciency?

In a patient with bilateral palpable gonads and genital ambiguity, the most com-

mon differential diagnoses are PAIS, 5α-reductase type 2 defi ciency, and 17β-

HSD3 defi ciency. The differentiating features among these disorders are

summarized in the table given below.

Parameters PAIS^

5 α-reductase

type 2 (^17) β-HSD3 defi ciency
Inheritance X-linked recessive Autosomal
recessive
Autosomal recessive
Genital ambiguity Less severe Severe Severe
Internal genitalia
(Wolffi an
derivatives)
Often normal Normal Normal
Mullerian
derivatives
Absent Absent Absent
a b
c
Fig. 9.17 ( a ) A 20-year-old individual with gynecomastia ( b ) bilateral scrotal testes ( c ) penile
hypospadias with redundant skin folds (after corrective surgery for hypospadias) due to PAIS
9 Disorders of Sex Development