Osteoporosis as a presenting symptom in a patient with small bowel Crohn#39;s disease

This case report describes an uncommon presentation of Crohn's disease with osteoporosis in a 38 year old male from Mumbai. He had low back pain and easy fatigue for 3 months duration. Initial evaluation showed normal spine radiograph with no fractures and normal calcium & vitamin D3 levels. Magnetic Resonance Imaging (MRI) of the spine showed features of osteoporosis (OP) with no evidence of disc prolapse or arthritis. Bone mineral density (BMD) evaluation confirmed the diagnosis of OP. He had mild iron deficiency anemia with occult blood loss in stool examination. Upper & lower gastrointestinal endoscopy did not reveal cause of gastrointestinal blood loss. A computed tomography (CT) scan of the abdomen showed jejunal wall thickening with absence of nodes or free fluid. Double balloon endoscopy (DBE) showed circumferential ulcers in the jejunum. Jejunal biopsy was suggestive of Crohn's disease (CD). He was treated with steroids, Azathioprine (AZA) and 5 aminocylic acid (ASA) drugs. His back pain reduced by 75% in one week & BMD showed improvement at 9 months. Osteoporosis is often observed in patients with CD due to mal-absorption of calcium, vitamin D3 deficiency and steroid therapy. Crohn's disease presenting as osteoporosis & its marked improvement with steroid therapy are unusual features in our case.