Prenatal diagnosis and obstetric management of Larsen's syndrome in a patient with an unrecognized family history of the disease

We report the third case of a prenatal diagnosis of Larsen's syndrome, whic h is the first report affecting both a 37-year-old primiparous caucasian wo man and her fetus not considered to have Larsen's syndrome until the findin g of bilateral clubfeet was demonstrated on screening ultrasound at 23 week s of gestation. History and physical examination of the pregnant woman reve aled severe impairment in the mobility of hip, elbow and knee joints starti ng in early childhood. Additional findings were spatulate thumbs and a flat nasal bridge. The mother of the pregnant woman demonstrated similar joint symptoms. The differential diagnosis of Larsen's syndrome was considered fo r the first time in both women. The patient wished to terminate her pregnan cy, as the potential early onset of the same disorder was suggested by the finding of clubfeet. An intraamniotic instillation of ethacridinic acid was performed. On pathological examination including radiography of the male s tillborn, various anomalies of the face, and upper and lower extremities we re demonstrated compatible with Larsen's syndrome.