A 26-year-old man was presented with recurrent abdominal pain and fever of unknown origin. Upper and lower gastrointestinal endoscopy showed no significant abnormalities. However, capsule endoscopy revealed multiple erosions with small elevated lesions extending from the jejunum to the ileum. Double-balloon enteroscopy demonstrated widespread erosive and protruding lesions in the ileum. Genetic analysis identified compound heterozygous MEFV mutations (Exon10 M694I and Exon2 E148Q), leading to a definitive diagnosis of familial Mediterranean fever.
The patient's father also exhibited mild clinical symptoms and carried a MEFV mutation; however, comprehensive gastrointestinal endoscopy revealed no abnormalities. These findings demonstrate intrafamilial heterogeneity in clinical and endoscopic manifestations despite shared MEFV mutations, and highlight the importance of comprehensive endoscopic evaluation for familial Mediterranean fever.
