Hypermagnesaemia causing mesenteric ischaemia and small bowel infarction.

We present a case of mesenteric ischaemia caused by hypermagnesaemia after ingestion of a large oral dose of magnesium citrate, which resulted in smooth muscle relaxation, hypotension and bowel infarction. The patient had a history of chronic bowel dysmotility and renal impairment. On operative exploration, the bowel was noted to have a distinct pattern of ischaemia along its antimesenteric border. Small bowel resection was performed, and the patient was left in discontinuity, with definitive repair and anastomosis performed 24 hours later. The patient's magnesium level was 8.39 mg/dL, which was treated with intermittent haemodialysis and eventually normalised over several sessions. Our patient recovered and was discharged after a month-long hospitalisation. She returned shortly after with respiratory failure and died. On review of the literature, we identified similar cases and present a pathophysiological mechanism of hypermagnesaemia causing mesenteric ischaemia, consistent between our cases and those already reported.