Unexpected cholinergic crisis caused by distigmine bromide: A case report

Distigmine bromide is a cholinesterase (ChE) inhibitor used to treat dysuria due to a hypotonic bladder. We encountered a case of cholinergic crisis caused by distigmine bromide, which resulted in a rapid decrease in serum ChE levels, hypothermia, respiratory failure, and circulatory failure within a short period of time. PATIENT CONCERNS: A 51-year-old man was admitted to a psychiatric hospital to treat behavioral disorders due to irritability and violent behavior. The patient was referred to our hospital for septic shock secondary to urinary tract infection and respiratory failure. He had not defecated for 5 days before visiting our hospital. He had moderate intellectual disability. Immediately after admission, he developed hand tremors and drooling. The airway was obstructed by drooling due to vomiting of yellow clear gastric juice. DIAGNOSIS: The patient’s high saliva volume, bradycardia, respiratory failure (54 breaths/min), constricted pupils (2.5/mm), poor oxygenation, and a history of oral medication were consistent with the diagnosis of cholinergic crisis due to distigmine bromide. INTERVENTIONS: On admission, the patient was immediately intubated. He was treated with noradrenaline (0.1 µg/kg/min) to increase his blood pressure. He was admitted to the intensive care unit (ICU). Since he had circulatory failure, vasopressin (approximately 1 U/h) was administered. Continuous intravenous atropine sulfate (0.6 mg/h) was also administered for high saliva volume. OUTCOMES: On the 8th ICU day, the patient’s drooling and bradycardia improved. The patient was physically and mentally stable, and transferred to the referring hospital. LESSONS: ChE levels and symptoms before onset may not be useful for the early detection and prevention of adverse effects of cholinergic crisis caused by distigmine bromide. In addition to known risks such as renal impairment and older age, constipation should be recognized and communicated as a risk factor.