Beneficial effect of digoxin-specific Fab antibody fragments in oleander intoxication

A 24-year-old man presented to the emergency department with nausea, vomiting, abdominal pain, and an acute confusional state of 6 hours' duration. Ten hours before admission, he had ingested a mixture of orange juice and six ground leaves, later identified as Nerium oleander (common pink oleander) leaves. His blood pressure was 100/80 mm Hg, and his pulse rate was irregular at 40/min. He was disoriented and his speech was dysarthric. Twelve-lead electrocardiography revealed a complete atrioventricular block, with a nodal escape rhythm of 40/min and diffuse ST depression. The presumptive diagnosis of acute oleander intoxication was confirmed by the detection of digoxin (1.0 nmol/L [0.8 ng/mL]) on radioimmunoassay. Despite intensive therapy, the patient's hemodynamic condition deteriorated. His blood pressure decreased to 70/40 mm Hg; he became oliguric and nonresponsive to external stimuli; and his potassium concentration rose to 6.8 mmol/L. Eighteen hours after admission, an empiric 480-mg dose of digoxin-specific Fab antibody fragments was administered intravenously over 30 minutes. Within minutes of the initiation of immunotherapy, the patient woke up; his blood pressure rose to 90/50 mm Hg; and he regained a sinus rhythm of 68/min with a prolonged PR interval. His potassium concentration decreased to 5.1 mmol/L within 15 minutes and normalized within 1 hour of therapy initiation. One day later, the 1 degree atrioventricular block disappeared, but the ST depression persisted for an additional 6 days. The value of digoxin-specific Fab antibody fragments in the treatment of plant glycoside and, in particular, oleander intoxication is discussed.