[Prevalence and possible causes of hypospadias]

Hypospadias is the most common congenital malformation of the male external genitalia. After the heart and circulatory system, it is the second most common developmental disorder in males. It is due to a midline fusion defect of the male urethra, which results in a misplaced urethral meatus. Hypospadias may be distal, medial and proximal. It may occur as an isolated defect or it may develop together with other genital disorders (retention of testes in one or both sides, microphallus, bifid scrotum) or with malformation of other organs. In some cases syndromic forms may also occur. Genetic factors play a crucial role in the occurrence of early developmental defect, but endocrine and environmental factors may also be important in the aetiology of hypospadias. It may be associated with various sex and autosomal chromosomal abnormalities. Monogenic and chromosomal causes of hypospadias accounts for about in 30% of all cases, while genetic factors remain unknown in 70% of cases. The authors summarize the development of the male external genitalia, the prevalence and possible causes of hypospadias. They propose that better understanding of the pathogenesis of the disease may contribute to the prevention and decreased prevalence of the disease.

Dysgenetic male pseudohermaphroditism

The authors report a case of a dysgenetic male pseudohermaphroditism with a 45,X/46,XY karyotype in a mosaic form, which was diagnosed in an infant. The one-week-old infant was evaluated because of proximal hypospadias and retention of the right testis. The results of hormonal tests were the followings: serum FSH 5.2 mU/ml; LH: 2.0 mU/ml; testosterone: 144.3 ng/dl; androstendione: 0.42 µg/l; 17-hydroxyprogesterone: 1.12 ng/ml. Chromosomal analysis revealed 45,X/46,XY karyotype. Fluorescent in vitro hybridization showed that 51% of the lymphocytes had the Y chromosome and the SRY gene. Analysis of the SRY showed no deletion in the AZF a,b,c regions. Pelvic magnetic resonance imaging indicated the presence of vagina between the bladder and the rectum, and it showed a mass measuring 15×8 mm in the right inguinal canal as well as an oval gonadal mass with a size of 13×7 mm in the left scrotum. During surgical intervention, performed at the age of one, the right gonad was removed and biopsy of the scrotal testis was performed. Histological examination revealed dysgenetic testis in both sides. The authors emphasize the necessity of cytogenetic and endocrinological investigations of newborns with perineoscrotal hypospadia and bilateral or unilateral maldescent testes immediately after birth. Surgical removal of the dysgenetic testicular tissue located in the abdominal cavity and its histological evaluation provides separation of mixed gonadal dysgenesis, dysgenetic male pseudohermaphroditism, bilateral gonadal dysgenesis and ovotestis in the 45,X/46,XY mosaic cases. An accurate evaluation is necessary for a correct sex assignment and for surgical intervention to prevent neoplastic degeneration of the dysgenetic gonad. Orv. Hetil., 2012, 153, 303–307.