The Fetus Points to the Diagnosis of Rare Skeletal Dysplasia: Stuve-wiedemann Syndrome: Retrospective Case Series and Prenatal Review.

Background: Stuve-Wiedemann syndrome (SWS) is a rare skeletal abnormality with extensive postnatal literature but limited prenatal studies. Our group had published a diagnostic algorithm to identify prenatal cases, yet, the challenge continues, especially when there is no family history of a similar condition. Methods: We retrospectively analyzed our experience of prenatal diagnosis of SWS over an 8-year period with ethical approval. Literature review of articles published until July 30, 2023 from PubMed, GeneReviews, and Genetics Home Reference using search parameters, "SWS," "prenatal," and "ultrasound" was conducted. Results: Three cases (diagnosed during the routine anomaly scan) were identified from our institutional review, and 11 cases from six studies from the literature review. Eight out of these 11 cases had a positive family history. SWS was recognized without positive family history in two patients from literature review and the three patients in the current study. The consistent findings that helped in reaching the suspicion were the typical pattern of long bone involvement (bowing of tibia > femora, relative sparing of the fibula and upper limb bones, normal scapulae, and clavicles), and the presence of camptodactyly. Despite the lack of sonographic evidence of narrow thorax, SWS is highly lethal, due to dysautonomic symptoms. Conclusion: In SWS, accurate ultrasound diagnosis is crucial to provide prognostic information as the lethality does not depend on pulmonary hypoplasia. Examination of the hands looking for camptodactyly is crucial in skeletal dysplasias to distinguish SWS from other bent bone osteochondrodysplasias, namely, campomelic and kyphomelic dysplasias. This prenatal distinction has important implications for prognosis.