Familial Mediterranean fever mimicking Crohn disease: A case report.

RATIONALE: Familial Mediterranean fever (FMF) is the most common form of autoinflammatory disease. We report a rare case of FMF with gastrointestinal lesions mimicking Crohn disease.

PATIENT CONCERNS: A 21-year-old Japanese man was referred to our institution, complaining of refractory diarrhea and weight loss of 14 kg during the past two years. He had presented with recurrent fever, abdominal pain, anal fistula and stomatitis. His father and one of his brothers had ulcerative colitis. Colonoscopy revealed longitudinal ulcers in the terminal ileum and aphthous erosions in the colorectum. Esophagogastroduodenoscopy revealed multiple linear erosions in the gastric corpus and circular erosions in the duodenal second portion. Biopsy from these lesions failed to detect epithelioid cell granulomas.

DIAGNOSES: Analysis of the genomic DNA revealed compound heterozygous mutations of E148Q/L110P in exon 2 of MEFV gene, suggesting a diagnosis of FMF.

INTERVENTIONS: The patient was subsequently given 0.5 mg of colchicine per day.

OUTCOMES: Follow-up colonoscopy 6 months later demonstrated that both the longitudinal ulcers in the terminal ileum and aphthous lesions in the colorectum had completely disappeared.

LESSONS: Our case suggests that patients with FMF possibly manifest gastrointestinal lesions mimicking Crohn disease.