ARSINE POISONING: MASSIVE HAEMOLYSIS WITH MINIMAL IMPAIRMENT OF RENAL FUNCTION

Possible production of arsenic hemoglobin adducts via exposure to arsine

OBJECTIVES

Arsine is an arsenic compound generated as a by-product in metal refineries. Accidental poisoning occurs sporadically; however, the administrative level for workers has not been established. Thus, it is essential to identify a highly specific biomarker for risk management in the workplace. The aim of this study was to identify an arsenic adduct, a potential biomarker, in the plasma.

METHODS

Preserved mouse blood was exposed to arsine in vitro, and the plasma was separated. The residual clot of the control sample was hemolyzed using ultrapure water, and the supernatant was collected. Plasma from mice exposed to arsine in vivo was also separated from blood. Immunoprecipitation assays were conducted using all samples after ultrafiltration, and three fractions were collected. The total arsenic concentration in each fraction was quantified using inductively coupled plasma mass spectrometry (ICP-MS). The three in vitro samples and the eluate fraction from immunoprecipitation were analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS).

RESULTS

In the exposed samples, the arsenic concentration in the fraction containing immunocomplexes was higher when immunoprecipitation was conducted with an anti-globin antibody. Three peaks were specifically observed in arsine-exposed samples after MALDI-TOF-MS analysis. Two of them were around m/z 15,000, and the other was m/z 15,700. The latter peak was confirmed even after immunoprecipitation.

CONCLUSIONS

Globin forms an adduct with arsenic after both in vitro and in vivo exposure to arsine. This adduct together with hemoglobinuria could be a candidate biomarker of acute arsine poisoning in plasma.

Oxidant stress and haemolysis of the human erythrocyte

The erythrocyte is a highly specialised cell with a limited metabolic repertoire. As an oxygen shuttle, it must continue to perform this essential task while exposed to a wide range of environments on each vascular circuit, and to a variety of xenobiotics across its lifetime. During this time, it must continuously ward off oxidant stress on the haeme iron, the globin chain and on other essential cellular molecules. Haemolysis, the acceleration of the normal turnover of senescent erythrocytes, follows severe and irreversible oxidant injury. A detailed understanding of the molecular mechanisms underlying oxidant injury and its reversal, and of the clinical and laboratory features of haemolysis is important to the medical toxicologist. This review will also briefly review glucose-6-phosphate deficiency, a common but heterogeneous range of enzyme-deficient states, which impairs the ability of the erythrocyte to respond to oxidant injury.

Drug-induced red cell dyscrasias

Major advances have been made in recent years in our understanding of the pathogenetic mechanisms of drug-induced blood dyscrasias, particularly those involving the red cell. Among the latter, hemolytic anemia is the most common. Drug-induced red cell destruction may occur on an immune basis or through disruption by the drug of red cell metabolism. The immunological basis of drug-induced hemolysis is reviewed with emphasis on the clinical and laboratory manifestations, differential diagnosis and the major mechanisms involved. Drug-induced oxidative hemolysis both in normal individuals and in those with certain enzymopathies, notably glucose-6-phosphate dehydrogenase deficiency, is summarized. Drugs may also produce red cell dyscrasias by acting on the immature erythroid compartment. Some of these inhibit erythroid growth by as yet poorly understood mechanisms. Others exert more specific metabolic effects in erythroid precursors. These include drugs which interfere with DNA synthesis causing megaloblastic erythropoiesis and those which disrupt mitochondrial function and the synthesis of heme manifested by sideroblastic erythropoiesis. A brief consideration of heme biosynthesis and the action of drugs which are associated with sideroblastic anemia, including the antituberculous agents, lead, alcohol and chloramphenicol is presented. Finally, where pertinent, an updated listing of drugs involved in red cell dyscrasias is included.

Postoperative autotransfusion of concentrated drainage blood in cardiac surgery. Experience with a new autotransfusion system

A new autotransfusion system was evaluated postoperatively in six patients undergoing aortocoronary bypass surgery. A hollow fiber hemofilter was integrated in the system, making it possible to concentrate the shed blood. The device functioned well, 825 ml diluted mediastinal drainage blood with a hematocrit of 23 was concentrated to a volume of 475 ml with a hematocrit of 36 and retransfused. Proteins were preserved, thus albumin concentration increased from 23 to 37 g/l in the autotransfusate. No negative side effects were registered after autotransfusion. A thorough coagulation study after retransfusion did not reveal any sign of activation of the coagulation cascade, nor were there any signs of an increased fibrinolysis.

Arsine toxicity aboard the Asiafreighter

Eight sailors on board the Asiafreighter were exposed to arsine that had escaped from a cylinder in the cargo hold. Four suffered severe toxicity and within a few hours had developed fever, weakness, nausea, vomiting, diarrhoea, abdominal pain, and haemoglobinuria. These patients had pronounced intravascular haemolysis, which in one patient was complete. This patient was also stuporose and anoxic, a condition attributed to failure of oxygen transport and sludging of red cell debris in the cerebral and pulmonary circulations, but he regained a normal level of consciousness after exchange transfusion. Evidence of marrow depression was present: the reticulocyte response to the haemolysis was poor and there was a thrombocytopenia. All four patients developed renal failure, one being totally anuric for five weeks. Two patients developed peripheral neuropathy, and one was still severely disabled six months after the incident. The other four patients had a similar, though less severe, illness.