Lambert syndrome is a very rare condition that was first described in four siblings from one French family. The syndrome is characterized by a set of unusual features affecting different parts of the body. These features include abnormalities of the face and neck, known as branchial dysplasia, which involve underdevelopment of certain facial structures along with extra skin tags near the ears and around the mouth. People with this condition also often have club feet, which means the feet may be twisted or deformed, and inguinal herniae. Additionally, there can be liver-related issues such as cholestasis, which happens due to a lower than normal number of small bile ducts in the liver. Intellectual deficit is also part of the condition, contributing to developmental challenges. This summary is based on the details provided about this rare syndrome.

The symptoms of Lambert syndrome include several distinct features. Branchial dysplasia may present with malar hypoplasia (underdevelopment of the cheekbones), a larger than normal mouth (macrostomia), preauricular tags (small skin tags near the ears), and meatal atresia (abnormalities in the openings of the ear canals). In addition to these, affected individuals may have club feet, inguinal herniae (when a part of the intestine protrudes through an opening in the lower abdominal wall), and signs of liver dysfunction, such as cholestasis from a reduced number of interlobular bile ducts. There is also an association with intellectual deficits.

Lambert syndrome was observed in four siblings within a single family, suggesting that there may be a genetic component. However, the exact cause and the genes involved are not yet identified or well understood. The condition appears to be inherited, but detailed information regarding genetics or other risk factors is currently limited for this condition.