A fatal case of torsemide abuse based on forensic autopsy findings.

Loop diuretics, such as torsemide, are generally prescribed to improve symptoms of edema in patients with heart failure. However, they are sometimes used inappropriately by individuals for weight loss or by athletes attempting to rapidly excrete water to mask other prohibited substances. Chronic abuse of loop diuretics can lead to persistent hypokalemia, which may cause renal impairment known as pseudo-Bartter syndrome, occasionally resulting in emergencies or fatalities. In the present study, a Japanese woman in her early 40s died after consuming approximately 150 tablets of 20-mg torsemide over six weeks prior to her death. The autopsy findings revealed that the kidneys had coarsely textured surfaces with fine granules, while the histopathological examination confirmed features consistent with pseudo-Bartter syndrome. The serum blood urea nitrogen and creatinine levels of the deceased patient were 28.7 and 1.64 mg/dL, respectively, which were more elevated than the standard reference values. A detailed toxicological analysis method was established to quantify torsemide in human whole blood using ultra-high-performance liquid chromatography-tandem mass spectrometry. The torsemide concentrations in the left and right cardiac blood were 2.97 and 2.56 μg/mL, respectively. Based on the case history, autopsy findings, histopathological examination results, and toxicological results, the cause of death was determined to be intoxication due to prolonged torsemide misuse. To our knowledge, this is the first reported autopsy case of a fatality resulting from an inappropriate use of torsemide. It was suggested that loop diuretics, including torsemide, should only be taken with a prescription from a doctor.