The Pena-Shokeir Syndrome in a Twin Pregnancy: A Rare Case Report.

Pena-Shokeir Syndrome (PSS) is a rare autosomal recessive disorder characterized by dysmorphic features, camptodactyly, arthrogryposis, intrauterine growth restriction, polyhydramnios, and pulmonary hypoplasia. Two types of this syndrome have been defined, differentiated by distinct clinical and genetic features. PSS is a potentially life-threatening condition, with most cases expected to be diagnosed prenatally via ultrasound. Genetic counseling is crucial to inform parents about recurrence risks and management strategies for future pregnancies. We report a case of PSS in a dichorionic diamniotic (DCDA) twin pregnancy. Despite normal prenatal ultrasounds, 1 twin was diagnosed postnatally with severe craniofacial anomalies, limb deformities, and pulmonary complications, consistent with PSS. In contrast, the second twin exhibited normal growth and development, with no anomalies identified. To the best of our knowledge, this is the third reported case of PSS in a twin pregnancy and the second involving a normal co-twin. This case aims to contribute to the existing literature by detailing the unique dysmorphic and clinical findings associated with PSS and emphasizing the diagnostic challenges in twin pregnancies.