The Unusual Cause of Abdominal Pain in a Patient with Coexistence of Behcet's Disease and Familial Mediterranean Fever: Cyst Hydatid Disease: Case Report

Behcet's disease (BD) is a rheumatologic disorder of unknown etiology. Familial Mediterranean fever (FMF) is another inflammatory disease which occurs due to the mutations in the MEFV gene. Both diseases have some common signs and symptoms, such as fever, arthritis, abdominal pain and cutaneous signs. Echinococcosis or hydatid disease is a zoonotic infection which mainly involves the liver and may cause abdominal pain accompanied by a large cystic mass. We report a case of 23-year-old male patient applied to our clinic with the complaints of recurrent pain and swelling in the left knee with abdominal pain. After the diagnosing coexistent BD and FMF in our patient we started colchicine treatment. Although knee pain and swelling improved, abdominal pain did not improve after this treatment. Therefore, we investigated other reasons for abdominal pain. In conclusion, concomitant occurrence of BD, FMF and also hydatid disease which may also cause abdominal pain was discussed in this case report.