A man in his 40s was found unconscious on a sofa in a communal residence for people with various disabilities. He appeared to have drunk 800 ml of undiluted
citric acid from a commercial
plastic bottle. The instructions on the label of the beverage specified that the beverage be diluted 20- to 30-fold before consumption. The patient was admitted to an emergency hospital with severe
metabolic acidosis (pH, 6.70; HCO3(-), 3.6 mEq/L) and a low ionized
calcium level (0.73 mmol/L). Although ionized
calcium and
catecholamines were continuously administered intravenously to correct the
acidosis, the state of acidemia and
low blood pressure did not improve, and he died 20 h later.
Citric acid concentrations in the patient's serum drawn shortly
after treatment in the hospital and from the heart at autopsy were 80.6 mg/ml and 39.8 mg/dl, respectively (normal range: 1.3-2.6 mg/dl). Autopsy revealed black discoloration of the mucosal surface of the esophagus. Microscopically, degenerated epithelium and neutrophilic infiltration in the muscle layer were observed. In daily life, drinking a large amount of concentrated
citric acid beverage is rare as a cause of lethal
poisoning. However, persons with
mental disorders such as
dementia may mistakenly drink
detergent or concentrated fluids, as in our case. Family members or facility staff in the home or nursing facility must bear in mind that they should not leave such bottles in places where they are easily accessible to mentally handicapped persons.