Crohn's Disease in a Patient With Bardet-Biedl Syndrome: Random Anomaly or Rare Phenotypic Trait?

Bardet-Biedl syndrome (BBS) is an autosomal recessive multisystem nonmotile ciliopathy. There are anecdotal reports of the co-occurrence of BBS and autoimmune diseases, including inflammatory bowel disease (IBD). We present the first case report of a child with BBS7 who developed Crohn disease, adding to the evidence on the association between BBS and IBD. A 13-year-old girl with BBS7 presented with abdominal pain and significant weight loss (-13%), but without other classical symptoms of IBD, such as diarrhea and blood loss. Fecal calprotectin was elevated, but on gastroscopy and colonoscopy, no macroscopic abnormalities were found. Ultrasound and MRI revealed an intestinal stenosis which was treated surgically. Histopathological examination confirmed the diagnosis Crohn disease. In conclusion, the reported co-occurrence of BSS and autoimmune diseases and the atypical presentation of IBD in this patient warrant a low threshold to perform diagnostic tests for IBD in patients with BBS and gastrointestinal symptoms.