An unusual cause of right sided hip pain in a patient with ulcerative colitis: iliopsoas muscle atrophia.

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) of uncertain etiology that is characterized by recurring episodes of inflammation primarily involving the mucosal layer and occasionally the submucosa of the colon. Joint manifestations are the most common extraintestinal manifestation (EIM) in IBD and occur in approximately 20%–30% of patients.1 Herein we report an unusual cause of right sided hip pain due to iliopsoas muscle atrophia in a patient with UC. A 38-year-old man was admitted to our outpatient service with complaints of diarrhea occurring six to seven times per day for three years and rectal bleeding for six months. He had also complained of right sided hip pain, which is not responding to NSAID, for two years. His history revealed no use of antibiotics, travel or suspected food consumption. His birth and early development were normal. Laboratory findings were as follows: serum hemoglobin 10.4 g/dl, white cell count 6500/mm3, platelet count 458.000/mm3, ESR: 92 mm/h and CRP: 2.91 mg/dl. Biochemical tests were within normal limits. Measurement of celiac-specific antibodies (antibodies to gliadin and endomysium) were all negative. Colonoscopy showed diffuse hyperemic mucosa and ulcerations in the rectum and sigmoid colon. Histopathological findings of the biopsy specimens were compatible with UC. Mesalamine 4 g/day was initiated and after starting the therapy with mesalamine, his symptoms besides right sided hip pain resolved. Dual energy X-ray absorptiometry and X-ray examinations included an AP pelvis, AP and lateral views of right hip were normal. In order to further explore the hip pain computerized tomography (CT) was performed. In axial CT imaging, iliacus, psoas major, gluteus medius, gluteus minimus, piriformis and obturator internus muscles were atrophic in the right side of the body. Gluteus maximus muscle was atrophic superiorly, but available inferiorly.