Late diagnosis of Bardet-Biedl syndrome in an 18-year-old patient − a case report and literature review

Bardet-Biedl syndrome (BBS) is a rare, autosomal recessive multi-system ciliopathy. Its diagnosis is based on a constellation of characteristic clinical symptoms that appear in childhood, including kidney defects, obesity, retinal dystrophy, polydactyly, intellectual dysfunction, and hypogonadism. We present a case of an 18-year-old girl with a postnatal diagnosis of postaxial polydactyly of the feet and hands and bilateral cutaneous syndactyly of the 2 nd and 3 rd toes, who successively developed most of the typical BBS manifestations. Despite this, the correct diagnosis was made only 3 months before adulthood in our clinic, to which the patient was referred because of suspicion of hypertension. Molecular testing confirmed the clinical diagnosis of BBS (homozygous variant c.619-1G>C in the BBS5 gene). The presented case is an example of a delayed diagnosis of BBS. The main reason was the lack of a comprehensive assessment of the multi-system disorders characteristic of BBS.