Prenatal Sonographic and Molecular Genetic Diagnosis of Popliteal Pterygium Syndrome

Popliteal pterygium syndrome (PPS) is an extremely rare autosomal dominant disorder, characterized by the cleft palate with or without cleft lip, limbs abnormalities with highly characteristic features of popliteal webbing, syndactyly, and genital abnormalities and nail anomalies. Prenatal diagnosis of PPS has been extremely rare. We describe a unique case of fetal PPS at 20 weeks of gestation. The diagnosis of PPS was based on the ultrasound findings of bilateral popliteal webbings, extending from posterior aspects of the upper thighs through the lower legs, resulting in restriction in knee extension, bilateral equinovarus feet with syndactyly, ambiguous genitalia and the grooved lip. Anatomical structures were otherwise normal. Trio whole-exome sequencing revealed a de novo heterozygous IRF6 gene mutation in the fetus, confirming the diagnosis with PPS. In conclusion, popliteal webbing or combination of facial cleft or cleft variants and bilateral abnormal postures of the lower limbs is suggestive of PPS and genetic diagnosis should be warranted.

Popliteal pterygium syndrome: case report from rural India

The popliteal pterygium syndrome is a congenital malformation that includes orofacial, musculoskeletal and genitourinary anomalies. It is also known as faciogenitopopliteal syndrome. It is autosomal dominant disorder. It has highly variable expressivity and incomplete penetrance. The incidence of the popliteal pterygium syndrome is 1/300000, which makes it an extremely rare condition. The most striking characteristic of this syndrome is popliteal pterygium, which consists of a net of connective tissue spreading from the ischial tuberosity to the calcaneus.In this study, authors present the case of a 1 day old male patient with cleft upper lip, cleft palate, bifid scrotum, popliteal pterygium and congenital talipes equinovarus (CTEV).

Hemiscrotal agenesis with complete testicular descent in Van der Woude syndrome: a new phenotypic feature

Van der Woude syndrome (VWS) and popliteal pterygium syndrome (PPS) spectrum are due to genetic variants in the IRF6 which phenotypically has been known to manifest with midline defects such as cleft lip and palate in VWS and additional nail, limb and genital anomalies in PPS. We report a case of VWS with the previously unrecognised phenotypic feature of hemiscrotal agenesis. While bifid scrotum has been reported in the more severe PPS, neither VWS nor PPS have previously noted hemiscrotal agenesis as part of the phenotypic picture. Hemiscrotal agenesis without evidence of any genetic anomaly has only been reported four times in the literature to date with two of these being accompanied by complete testicular descent. Treatment options include topical androgen application and/or scrotoplasty to allow for adequate testicular thermoregulation and development to occur.