Infections in acute leukemia: an analysis of 240 febrile episodes

Abstract

Infections are the major cause of morbidity and mortality in acute leukemia patients. Case records of 91 consecutive patients (AML-48, ALL-40, RAEB-t/AML-3) treated between January 1997 and July 1999 were studied to determine the type, frequency and severity of infections. Patients' median age was 36 y (range 6-66) and male to female ratio was 2.5:1. A total of 240 febrile episodes were recorded; of them, 162 were associated with neutropenia (absolute neutrophil count, ANC<500/mm3) and 78 were without neutropenia. Among the neutropenic episodes, an infectious etiology could be documented in 52%; the remainder (48%) were defined as isolated febrile episodes. Chest was the most common site of infection (35. 7%) followed by skin, soft tissue (13%), GIT (7%) and genitourinary tract (6%) infections in order of decreasing frequency. Microbiologically, gram positive organisms (staphylococcus aureus, coagulase negative staphylococcus, streptococcus, enterococcus) were the most common isolates (52.8%) followed by gram negative organisms (E. coli, klebsiella, pseudomonas) in 42.8% of isolates. Two patients had pulmonary tuberculosis and three patients had fungal infections (candida-2, aspergillus-1). Among non-neutropenic patients, infection could be documented in 36%; the remaining 64% were isolated febrile episodes. Gram negative infections were documented in 50%, gram positive in 30% and fungal infections (candida-4, aspergillus-1, mucormycosis-1) in 20% of them. A combination of third generation cephalosporin and an aminoglycoside were used in 79% of episodes initially; a combination of a newer penicillin and aminoglycoside (4.6%), double betalactums (4.1%), oral antibiotics (9.8%) and others were used in the remaining episodes. Fever resolved in 38% of episodes using the above combinations; in the remainder second line antibiotics (mainly vancomycin) and antifungals (amphotericin-B) were added empirically or depending on culture and sensitivity. In 52.5% of episodes fever resolved after addition of second line antibiotics and antifungals. 11 of 91 patients died of infectious complications in this study. There is a need for improvised diagnostic tests to detect infections early as well as for new therapies to overcome antimicrobial resistance.