Arch Hellen Med, 26(3), May-June 2009, 366-373
Infections in pediatric patients with acute lymphoblastic leukemia during the entire course of treatment
K. KATSIBARDI,1 V. PAPADAKIS,1 A. HARISIADI,2 S. HAIDAS,1 S. POLYCHRONOPOULOU1
OBJECTIVE To assess the type, frequency, severity and outcome of all infectious episodes in a cohort of pediatric patients with acute lymphoblastic leukemia (ALL), during the entire course of leukemia treatment.
METHOD Eighty six patients diagnosed with ALL, during the period 4/1994-2/2000 in a Pediatric Hematology-Oncology unit were enrolled in the study. The patients were treated according to a modified ALL-BFM protocol. Retrospective analysis was made of all types of infections, according to the treatment phase and the degree of neutropenia.
RESULTS A total of 610 infectious episodes were recorded, most of which (57%) were documented during maintenance. Of the 347 episodes encountered during maintenance, the commonest diagnosis (40%) was non-specific viral upper respiratory tract infection (URI). Furthermore, 38 of 58 total specific viral infections occurred during maintenance: Sixteen herpes simplex, 7 varicella and 10 herpes zoster (VZV). During induction 123 infections (20.3%) were documented, with bacteremia (n=29) and episodes of fever of unknown origin (FUO) (n=28) being the commonest infectious episodes. The number of cases of Gram (-) bacteremia was 50% (26/52). The majority of the infections (59.5%) occurred in the absence of neutropenia (absolute neutrophil count, ANC >1.0 K/μL). Fewer infections (9.3%) were recorded with concurrent very severe neutropenia (ANC <0.1 K/μL), although 38.5% of positive blood cultures were documented with severe neutropenia. Infection related fatality was negligible.
CONCLUSIONS Most of the severe infections occurred during the induction phase of ALL treatment. Gram (+) and Gram (-) bacteremia were observed in almost equal proportions. URIs were the commonest infections during the entire treatment and during maintenance. Specific viral infections represented a smaller percentage of the total; VZV was the commonest pathogen. Infectious complications represented a significant morbidity factor during ALL treatment, but notably, mortality was negligible.
Key words: Acute lymphoblastic leukemia, Childhood, Infections, Neutropenia.