Genetic sequencing of a patient with Kallmann syndrome plus 5α-reductase type 2 deficiency

and 6.78 at baseline, and 4.41 ug l−1, 168.5 ug l−1, and 26.40 after human chorionic gonadotropin (HCG) stimulation, respectively. Other hypothalamic-pituitary-axes' functions were normal. The patient was treated with HCG 2000 U i.m. 3 times every week for 9 months, and then human menopausal gonadotropin (HMG) 75 U i.m. was added 3 times a week for another 3 months. Mild Dear Editor, Kallmann syndrome (KS) is a phenotypically and genetically heterogeneous disorder featured by hypogonadotropic hypogonadism and congenital hyposmia or anosmia, accompanined with renal dysplasia, hearing loss, and craniofacial defects sometimes. More than 20 genes have been identified causing KS either alone or in combination. 5α-reductase type 2 deficiency (5α-RD) caused by SRD5A2 gene mutation is a rare disease characterized by elevated ratio of testosterone (T) to dihydroteststorone (DHT). The clinical spectrum of 5α-RD is heterogeneous, ranging from the classic phenotype to males with hypospadias and even isolated micropenis. Here, we report a male KS patient accompanied with mild 5α-RD diagnosed from genetic sequencing and clinical analysis. A 28-year-old male (46, XY) was referred for no secondary sexual characteristics and anosmia. At birth, he had bilateral cryptorchidism, anosmia, and deafness in the left ear. Figure 1a shows the patient’s olfactory bulbs and tracts while Figure 1b shows the normal individual. Figure 1c shows his flat pituitary. Bilateral orchidopexy was performed at age five, and there is no prior treatment. The distance between the top of the head to the superior margin of the symphysis pubis was 87.2 cm and from the inferior margin of the symphysis pubis to the sole of the foot was 93.0 cm, and distance between outstretched arms was 187.0 cm. He had bilateral cubitus valgus, and his bone age was 16 years old (Figure 1e). No remarkable frontotemporal hairline recession or acne was noted. Each testicle was in the scrotum without hypospadias. Genital development was Tanner genital stage 1. His pelvic MRI showed prostate dysplasia, mullerian duct cyst (Figure 1f), and seminal vesicles dysplasia (Figure 1g). The MRI of normal seminal vesicles is given in Figure 1h. Normal respond of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) was seen after the subcutaneous injection of triptorelin 100 mg. The results of the triptorelin stimulation test at baseline and 15, 30, 60, 90, and 120 min after injection were LH 0.08, 1.30, 1.48, 1.67, 1.81, and 2.26 (normal: 2–12) IU l−1; FSH 1.02, 2.03, 2.47, 3.03, 3.13, and 4.20 (normal: 1–8) IU l−1, respectively. T, DHT, and T/DHT ratio were 0.32 (normal: 1.58–8.77) μg l−1, 47.58 (normal 57.5–355.0) ug l−1, LETTER TO THE EDITOR