ABSTRACT
Infection is a common complication in patients undergoing hemodialysis. Despite the improvement of dialysis techniques, infection especially by bacteria remains the primary cause of death in these patients. Laboratory diagnosis is made by blood culture, the result of which may not be available for several days and during this period endotoxemia may lead to septic shock. Therefore, attempts at developing simple and rapid diagnostic tests are underway. In the present study, the Limulus Amebocyte Lysate [LAL] assay was used to detect endotoxin and compare its results with that of blood culture in hemodialysis patients. This study involved 278 chronic hemodialysis patients. LAL assay and blood culture were performed and the results were compared. 38 blood cultures were positive and the types of bacteria were determined with biotyping and serotyping methods. LAL assay was used to determine the presence of endotoxin in positive blood cultures. Endotoxin was detected in 15 patients. The sensitivity and specificity of LAL assay for Gram-negative bacteria were 88% and 95%, respectively. The frequency of bacteremia in patients was 13.6%. The prevalence of Gram-negative bacteremia [GNB] was 44.7%. Escherichia coli accounted for the majority of pathogenic microorganisms and Staphylococcus aureus was the most commonly encountered Gram-positive bacterium. Results of present study demonstrated that LAL assay is a rapid, sensitive and simple method. An excellent correlation was found between results of LAL assay and the presence of GNB. Gram-negative bacteria accounted for approximately 50% of documented infections. Endotoxin originating from Gram-negative bacteria was found to contribute to the inflammatory responses of patients with sepsis