An 81-year-old woman with stage 4 chronic kidney disease (focal segmental glomerulosclerosis) requiring steroids and immunosuppression with mycophenolate mofetil presented with left iliac fossa (LIF) pain, anorexia and rectal bleeding with mucus. Examination and investigations revealed no pyrexia, LIF tenderness, supraclavicular subcutaneous emphysema or leucocytopenia. An erect chest x-ray (figure 1) ruled out pneumoperitoneum but demonstrated extensive supraclavicular subcutaneous emphysema and pneumomediastinum. No pneumothorax was present.