Penoscrotal transposition and associated anomalies: report of five new cases and review of the literature.

We present the largest single series of cases (n = 5) of penoscrotal transposition (PST) with carefully documented nongenitourinary/anal anomalies, none of which fell into categories of known syndromes, associations, sequences or chromosome disorders. Several unexpected anomalies were observed including coloboma of the iris and retina, hydrocephalus, microcephaly, diaphragmatic hernia, tracheo-esophageal fistula/esophageal atresia and cleft palate. The most frequent anomalies other than PST were renal defects (100%) such as renal agenesis and dysplasia, imperforate anus (60%), central nervous system anomalies (60%) and preaxial upper limb defects (40%). Cardiovascular defects (atrial septal defect, double aortic arch with vascular ring) were noted in only one case. The surviving patients (3/5) had postnatal growth failure and mental retardation. Our 5 PST patients are compared to 16 well-documented cases from the literature. The overall incidence of various extragenital abnormalities were: renal (90%), mental retardation (60%), imperforate anus (33%), central nervous system (CNS) anomalies (29%), vertebral defects (29%), preaxial limb defects (24%) and congenital heart disease (19%). PST is a rare heterogenous anomaly, the detection of which should warrant careful clinical evaluation to rule out other anomalies, especially of the urinary system, gastrointestinal tract, upper limbs, craniofacial region and central nervous system. PST may be a localized field defect involving the genitourinary system; however, the wide variety of more distant defects noted in our series and the literature would raise doubt about that assumption. The high frequency of growth deficiency and mental retardation has also not been given due respect as accompanying problems associated with PST.