Late-onset non-obstructive mesenteric ischemia (NOMI) resulting from delayed absorption of overdosed antihypertensive drugs: An autopsy case report.

Non-obstructive mesenteric ischemia (NOMI) is caused by reduced blood flow to the intestines without physical occlusion in the mesenteric artery. Previous reports show that drug overdose occasionally induces late-onset NOMI; however, in most cases, the reason for the delayed onset is unclear. Here, we present an autopsy case of late-onset NOMI that was induced by a drug overdose. An 80-year-old man was admitted to the intensive care unit because of severe hypotension after an overdose of antihypertensive drugs. He received vasopressor therapy and continuous hemodiafiltration dialysis; however, gastrointestinal decontamination was not performed. He began to recover but developed acute mesenteric ischemia on the evening of day 4 and died on day 5. Autopsy showed discontinuous submucosal bleeding from the duodenum to the colon; there was no thrombus in the mesenteric artery, which led to a diagnosis of NOMI. In the stomach, there was 250 mL of reddish-brown fluid with a muddy brown substance. Histologic examination revealed ischemic necrosis in the small intestine. Quantitative analysis of serum collected during hospitalization revealed that nifedipine and cilostazol levels had peaked on day 3 of hospitalization. The formulation of nifedipine was a controlled-release tablet, and the low water solubility of cilostazol may have caused the tablets to adhere and remain in the stomach. Therefore, the drugs had been released into the blood stream several days after hospitalization, leading to delayed-onset NOMI. In cases of overdose, it is crucial to consider the formulation and properties of the involved drugs when determining medical treatment.