Infections in Patients with Acute Leukemia: Comparison of Induction Chemotherapy Group and Reinduction Chemotherapy Group

Choi, Su Mi; Lee, Dong Gun; Park, Yoon Hee; Kim, Yoo Jin; Kim, Hee Jae; Lee, Seok; Choi, Jung Hyun; Yoo, Jin Hong; Kim, Dong Wook; Lee, Jong Wook; Min, Woo Sung; Shin, Wan Shik; Kim, Chun Choo

Abstract

BACKGROUND: Despite the recent advance in chemotherapy and supportive care, infection remains one of the major complications in patients with acute leukemia. The purpose of this study was to determine the patterns and trends of infections in patients with acute leukemia and to find out differences in the infectious features of each chemotherapy group.
METHODS
We reviewed medical records of total 326 cases with acute leukemia who had received induction or reinduction chemotherapy at the Catholic Hemopoietic Stem Cell Transplantation Center during Jan. 1998 and Dec. 1999, and compared these data with our previous data published in 1994 and 1999.
RESULTS
Out of total 326 cases, 173 cases received induction chemotherapy (IC) and 153 cases received reinduction chemotherapy (RC). Underlying diseases were 211 cases of acute myeloid leukemia and 115 cases of acute lymphoid leukemia. Median age of the patients was 33 years (33 in the IC group vs 31 years in the RC group, P<0.05). Overall, 87% of the cases experienced at least one febrile episodes. Mean leukocyte count at the onset of fever was significantly lower in the RC group than in the IC group (477/mm3 vs 293/mm3, P=0.001). Infections were classified as : 46.1% of microbiologically defined infection, 35.9% of clinically defined infection and 18.0% of unexplained fever. Most common site of infection was respiratory tract in the IC group, and gastrointestinal tract in the RC group. Escherichia coli was the most commonly isolated organism in each group, and gram-negative bacteria including E. coli were more frequently isolated in the RC group than in the IC group (P< 0.05). Infection-associated mortality was significantly higher in the RC group than in the IC group (6.9% vs 11.8%, P=0.03). Comparing with our previous data, the overall mortality was reduced from 50% (early of the 1980s) to 12.3%, whereas the infection still contributed major fraction of mortality and morbidity in the management of patients with acute leukemia.
CONCLUSION
The patterns of infection between IC group and RC group are somewhat different and has been changing due to many factors. New preventive, diagnostic, and treatment strategies should be developed, and prophylactic antimicrobials should be meticulously used to prevent the emergence of resistant organisms.