A Rare Case Report of Bardet–Biedl Syndrome: A Syndrome of Pentad Symptoms

Abstract

Bardet–Biedl syndrome (BBS) is a clinically and genetically heterogeneous disorder that manifests as a result of primary cilia impairment, characterized by retinitis pigmentosa, obesity, mental retardation, hypogonadism, and polydactyly. The five findings together are called “the pentad” and are found in most of the cases. This is the case of a 14-year-old boy, 2nd issue of consanguineous marriage of his parents, having a positive family history, who presented with progressive dimness of vision, learning disability, increased hunger, and weight since childhood. Initially, there were impaired night vision and peripheral vision problems, and later loss of color vision. He had no hearing problem, anosmia, cold intolerance, or steroid-taking history. His intranatal and postnatal history was uneventful except slightly delayed developmental milestone. His body mass index was 32.7 kg/m2, waist–hip ratio was 1.08, height was in the 50th centile on the growth chart. He had polydactyly, high-arched palate, acanthosis nigricans, and buried penis; testicular volume was prepubertal. Laboratory findings revealed high triglyceride, impaired glucose tolerance, hypogonadotropic hypogonadism, and grade-III fatty liver. He had bony spicule-like pigmentation in the periphery of both eyes suggestive of retinitis pigmentosa. Based on these data, BBS was diagnosed. In conclusion, BBS is a rare clinical syndrome that may go unnoticed by many clinicians. Renal failure is the leading cause of morbidity and mortality in patients with BBS. Therefore, early detection of BBS is vital to halt the progression of renal impairment.