Admission with anemia and reported bloodloss, which was not seen by professional health care workers. CD4 count 70/ml, viral load < 50 copies, HAART since 6 month. Gastroscopy and coloscopy showed no evidence of current GI bleeding and revealed no bleeding source. Staging by CT scan (cerebral, cervical, thoracical and abdominal) showed lymphnodes smaller than 1 cm, no suspicion for lymphoma, especially in the small intestine. Bone marrow biopsy was without pathological findings. The patient received blood transfusion, hemoglobin levels remained constant. To complete our diagnostic approach we performed a single ballon enteroscopy via oral routine. Approximatly 210 cm a.d. we found a semicircular ulcerating lesion followed by a circular protruding and ulcerating tumor which could not be passed. Histology showed a b-cell lymphoma (diffuse large cell, CD20 positive).