Lethal cardiotoxicity from quaternary ammonium compounds contained in an unguarded household detergent at a psychiatric facility

•A youth suicide, following ingestion of quaternary ammonium compounds, is reported.•The cause of death was acute heart failure due to toxic myocarditis.•A direct damage of myocardiocytes and a superimposed immune response are discussed.•The patient ingested the toxic detergent, left unguarded, in a psychiatric facility.•Planned clinical risk-management measures in psychiatric facilities are necessary.

Here, referred for the first time in literature, we present the forensic case of death, with suicidal intent, following ingestion of a conspicuous amount of quaternary ammonium compounds contained in an unguarded bottle of household detergent. The deceased person was a young female patient at a psychiatric facility; the cause of death was acute heart failure due to spotty infiltration of neutrophils, lymphocytes and plasma cells in the myocardial tissue, observable in the course of toxic myocarditis. The dominant pathogenetic factors involved are direct damage of myocardial cells and a superimposed immune response extending to the epicardial perivascular spaces. This rare form of acute myocarditis has never been previously described. Moreover, this fatal event emphasizes the need for planned clinical risk-management measures and for guidelines to prevent future adverse events of this kind in psychiatric facilities.