Complicated retroperitoneal diverticulitis presenting with abscess and acute limb ischemia.

This case highlights a rare presentation of diverticulitis of the sigmoid colon with perforation into the retroperitoneum complicated by abscess, vertebral osteomyelitis and acute lower extremity ischemia. A late 40-year-old man presented to an emergency department with acute ischemia of his left lower extremity. He was tachycardic with a leucocytosis, an unremarkable abdominal exam and a pulseless, insensate and paralysed left lower extremity. Imaging revealed sigmoid thickening, an abscess adjacent to iliac vasculature and occlusion of the left popliteal artery. The abscess came in contact with prior spine anterior lumbar interbody fusion (ALIF) hardware at L5-S1 vertebrae. The patient was taken urgently to the operating room for embolectomy, thrombectomy and fasciotomy. He was started on antibiotics and later underwent operative drainage with debridement for osteomyelitis. Non-operative management of the complicated diverticulitis failed, necessitating open sigmoidectomy with colostomy. 1 year later, he was symptom-free and the colostomy was reversed.

Iatrogenic immunodeficiency-associated lymphoproliferative disorder presenting as small bowel perforation.

A woman in her late 50s on mycophenolate for limited systemic sclerosis presented with abdominal pain. Vital signs and investigative evaluations were normal. Cross-sectional imaging identified gastric and small bowel wall thickening, free fluid, and pneumoperitoneum. In the operating room, a small bowel perforation was found and resected. Postoperatively, immunosuppression was held and she completed a course of amoxicillin/clavulanate. She discharged home and re-presented on postoperative day 8 with seizures and was found to have a frontal brain mass which was biopsied. Pathology from both the resected bowel and brain biopsy demonstrated Epstein-Barr virus-positive B-cell lymphoproliferative disorder with polymorphic B-cell features. The patient's immunosuppression was discontinued, and she was enrolled in a clinical trial for chemotherapy. Lymphoproliferative disorder can present years after immunosuppression initiation with either spontaneous perforation or solid tumour. Pathological assessment determines treatment options. Heightened concern for atypical clinical presentations in immunosuppressed patients is always warranted.