Microphallus early management in infancy saves adulthood sensual life: A ‎‎comprehensive review

Table 4 Differences between 5α-reductase type 2 deficiency and androgen insensitivity syndrome

	5αR2D	AIS
Primary genetic defect	It is due to a deficiency in the 5α-reductase type 2 enzyme that converts testosterone to DHT	Genetic mutations in the androgen receptor gene result in the inability of cells to respond to androgens (e.g., testosterone)
Inheritance	Autosomal recessive	X-linked recessive
Chromosome location	2p23	Xq11-q12
Genotype	Typically, 46, XY karyotype (male genotype)	Typically, 46, XY karyotype (male genotype)
Phenotype	Ambiguous genitalia in male infants. Varying degrees of under-virilization during puberty	Variable degrees of feminization and incomplete masculinization despite the presence of male internal and external genitalia
Hormonal profile	Reduced levels of DHT. Normal or elevated levels of testosterone, elevated LH	Elevated testosterone levels due to a lack of androgen receptor responsiveness, elevated LH, and normal MIF
Response to androgens	Reduced response to androgens due to inadequate conversion of testosterone to DHT. DHT plays a key role in the process of sexual differentiation in the external genitalia and prostate during the development of the male fetus	Lack of response to androgens despite normal or elevated testosterone levels
Internal reproductive organs	Typically have normal male internal reproductive organs (e.g., testes, vas deferens, epididymis). Testes located in the inguinal canal or ‎scrotum	Typically, they have normal male internal reproductive organs. Testes located in the abdomen or ‎inguinal canal
External genitalia	Ambiguous or underdeveloped male external genitalia	External genitalia: Neonate: Female (complete type). But may appear as normal male external genitalia but with varying degrees of feminization (partial type)
Pubertal development	Affected males still develop typical masculine features at puberty (deep voice, facial hair, muscle bulk) since most aspects of pubertal virilization are driven by testosterone, not DHT	Minimal virilization, with absent or minimal facial hair, high-pitched voice, and breast development
Fertility	Reduced fertility due to underdeveloped reproductive organs	Infertility due to absent or underdeveloped reproductive organs
Psychological Impact	Gender dysphoria may occur due to ambiguous genitalia and delayed or incomplete virilization	Gender dysphoria may occur due to female-appearing genitalia and lack of virilization
Treatment	Hormone replacement therapy may be considered to supplement DHT. Testosterone therapy may be used to ‎induce virilization	Hormone replacement therapy is not effective due to insensitivity to androgens. In complete type, the patient is treated as female, and estrogen therapy is indicated with orchidectomy. Orchidectomy aims to prevent possible malignant degeneration of the testes. Psychological support and surgical interventions may be considered

5αR2D: 5α-Reductase Type 2 Deficiency; AIS: Androgen Insensitivity Syndrome; DHT: Dihydrotestosterone; LH: Luteinizing hormone; MIF: Müllerian-inhibiting factor.