Renal calculi following superior mesenteric artery occlusion

A 48-year-old woman developed an occlusion of the superior mesenteric artery resulting in infarction of the jejunum, ileum and proximal colon up to the splenic flexure. She underwent extensive small intestinal resection followed by a jejunocolic anastomosis; the residual jejunal length was 35 cm. She was morbidly obese prior to intestinal resection (weight 102 kg; BMI 45.7) and steadily lost weight following the surgery. Initially, she experienced marked diarrhoea post-resection; this improved until she was experiencing four to eight bowel movements daily. She re-presented two years later with painless haematuria when she was found to have multiple calculi in the left kidney. She underwent lithotripsy following which a temporary renal stent was inserted for six months. Baseline serum electrolytes, calcium and liver profiles as well as 24-hour urine calcium and urate excretion at this time were normal. She had significant renal impairment with subnormal creatinine clearance as well as raised serum creatinine and urea following this episode, which resolved partially. She was advised to go on a low-calcium diet. She was re-evaluated three years following intestinal resection when her body weight was 53.5 kg (BMI 23.6). She continued to have frequent bowel movements and was almost certainly malabsorbing. She had noticed foul smelling and pale faeces which were difficult to flush. Cholestyramine therapy had no effect on the diarrhoea although some relief was obtained with codeine phosphate.