Hydroxocobalamin treatment of acute cyanide poisoning from apricot kernels

Abstract

BACKGROUNDCyanide, a mitochondrial toxin is one among the most rapidly acting lethal poisons known to man. If untreated, exposure to cyanide can kill within minutes. Current treatment of cyanide poisoning includes the intravenous administration of hydroxocobalamin. This case report describes unusual cyanide poisoning due to ingestion of large quantities of apricot kernels containing amygdalin, a compound which forms hydrogen cyanide when metabolised in the intestine and thus induces typical symptoms observed with cyanide poisoning. CASE PRESENTATIONA 35-year-old mentally ill woman was admitted while conscious to our emergency department and clinical toxicology unit. The patient's parents reported that they found their daughter in the living room, surrounded by apricots from which she had extracted and eaten the cores. Further investigation revealed that the woman had swallowed 20-30 apricot kernels, with extrapolation from the remaining uneaten kernels suggesting that this equated to a total kernel consumption of 10-15 g. The approximate time of consumption was 30 min prior to admission, and on arrival, the patient was uncooperative and appeared asymptomatic. INVESTIGATIONSThe following measurements were taken: blood pressure 120/70 mm Hg, pulse rate 120 beats/min, respiratory rate 26 breaths/min, temperature 37.5°C and SpO 2 on room air 98%. Arterial blood gas analysis also revealed slight metabolic acidosis (pH 7.33, pO 2 90 mm Hg, pCO 2 35.5 mm Hg, and HCO 3− 20 mmol/l). The anion gap at admission was 19 mEq/l. Lactate and cyanide levels were not measured and no signifi cant ECG changes were noted. TREATMENTAfter consultation with the clinical toxicology unit, she was subjected to a gastric lavage. One hundred grams of activated charcoal and 30 g of magnesium sulphate were administered, followed by hydration therapy (1000 ml of normal saline) and ECG monitoring. Approximately 70 min postingestion, the patient experienced headache, nausea and dyspnoea. Her vital signs were: blood pressure 75/50 mm Hg, pulse rate 145 beats/min, respiratory rate 30 breaths/min and SpO 2 93% (with supplementary oxygen mask: 3l/min). Arterial blood gas analysis revealed metabolic acidosis (pH 7.20, pO 2 75 mm Hg, pCO 2 34.2 mm Hg and HCO 3− 16 mmol/l). The anion gap was now 23 mEq/l. Two 1 ml phials of 5% amyl nitrite via inhalation, and intravenous infusion of 50 ml of 25% sodium thiosulphate in 1000 ml of 5% glucose solution (infusion rate 5 ml/min) were subsequently administered as recommended by the toxicologist. Following this therapy, the patient's methaemoglobin level was 10%, prompting the administration of oxygen via a facemask. Electrolytic solution (1000 ml) was then administered. This slightly improved her vital signs and her blood pressure rose to 80/60 mm Hg. SummaryClinical experience with hydroxocobalamin in acute cyanide poisoning via ingestion remains limited. This case concerns a 35-year-old mentally ill woman who consumed more than 20 apricot kernels. Published literature suggests each kernel would have conta...

Evaluation of Siberian Apricot (Prunus sibirica L.) Germplasm Variability for Biodiesel Properties

“…However, Siberian apricot seed kernels (SASK) contain amygdalin that can decompose into glucose, benzaldehyde and hydrocyanic acid, which is a potential cause of cyanide poisoning. In humans, the lethal dose of cyanide is normally assumed to be 1.5 mg/kg (105 mg for a 70 kg adult) [6], which equates to about 36.0 g of SASK for adult (cyanide content of apricot kernels was reported to be 2.92 mg/g [7]). The SASK thus cannot be used in the mass production of food or medicines.…”

An unusual presentation of chronic cyanide toxicity from self-prescribed apricot kernel extract

“…One clinical scenario initially describes suspected ingestion of 20–30 apricot kernels with no symptoms 40 min after ingestion, with development of symptoms 70 min after ingestion of tachycardia, hypotension, tachypnoea, with a peripheral SpO2 reading of 93% with 3 L/min of supplemental oxygen, metabolic acidosis of 7.20 and an anion gap of 23 4. Another scenario describes a life-threatening presentation of metabolic acidosis causing weakness and dyspnoea progressing rapidly to coma 11.…”

“…Another scenario describes a life-threatening presentation of metabolic acidosis causing weakness and dyspnoea progressing rapidly to coma 11. Both scenarios required administration of sodium thiosulfate,4 11 while in the first scenario the patient also received amyl nitrate and hydroxycobalamin 4…”

“…A recent reported case of apricot kernel toxicity showed the presence of high levels of methaemoglobin (10%) with an associated SpO 2 of 93% with supplemental oxygen 4. This was however, following treatment with amyl nitrate, a generator of methaemoglobin used to induce the formation of the cyanomethaemaglobin, through sequestration of cyanide ions, minimising the toxic effect of free cyanide on cytochrome oxidase.…”

Rosaceae Juss.

“…The threat in humans is mainly associated with consumption of seeds of species of Prunus. Ingestion of apricot seeds by adults as a health food or for other purposes is rarely a problem, but acute cyanide toxicity can occur (Suchard et al 1998;Cigolini et al 2011). Ingestion of as few as 5 seeds may result in serious signs of intoxication.…”