ABSTRACT
Glucose 6-phosphate dehydrogenase [G6PD] deficiency is the most common of all clinically significant enzyme defects. A long list of drugs thought to cause haemolysis in patients with this enzyme defect. To determine whether chloramphenicol and salicylate can act as in vitro exogenous oxidizing agents and subsequently cause haemolysis of G6PD deficient erythrocytes and matching the result with the data obtained from the clinical observations which includes the intake of trimethoprim-sulfamethoxazole, salicylate or nalidixic acid by favic patient. Sixty six patients admitted to the hospital [Karbala teaching hospital for Children, Karbala, Iraq] with history of sudden onset of pallor and dark urine after fava beans ingestion were studied. Each patient was fully examined and his parents were asked about the type of fava beans ingested and the past drug history. Of the sixty six patients, ten were evaluated 1-3 months later and blood samples were taken from them along with blood samples from ten healthy volunteers. Blood samples from both groups were incubated in vitro with chloramphenicol and salicylate separately. Mean [SD] of methaemoglobin concentrations at baseline and after incubation with therapeutic and toxic concentrations of chloramphenicol [15 micro g/ml and 25 micro g/ml] and salicylate [150 micro g/ml and 300 micro g/ml] were calculated for both the control and the study groups. Paired t-test showed no significant differences [P> 0.05] in methaemoglobin concentrations at baseline and after incubation with therapeutic and toxic concentrations of these drugs. Mean percentage differences from baseline for G6PD deficient group were not significantly different from control group at both concentrations of these drugs as tested by student t-test. Hemolysis in G[6]PD deficient patients occurs mainly after fresh fava beans ingestion. chloramphenicol and acetylsalicylic acid do not cause significant hemolysis in G[6]PD deficient erythrocytes in vitro