Eva Bilikova

Acinetobacter baumanii (AB) bacteremia in cancer patients

© Springer-Verlag 2001 Acinetobacter baumanii (AB) is the third most common, gram-negative, bacteremia-causing bacteria in the cancer patient population [1, 2]. In addition, large surveillance studies on nosocomial infections within the past 2 years show an increasing incidence of AB infections worldwide [3, 4, 5]. A total of 157 episodes of AB bloodstream infections in 157 patients from 8 major teaching hospitals (2650 beds) in 5 cities in Slovakia (5.5 million inhabitants) including the National Cancer Institute, National Institute of Heart Diseases, and National Institute of Lung Diseases within 1 year (1999) were evaluated in a nationwide study in Slovakia, and 162 strains of AB were isolated. Of the 157 patients, 58 had cancer as the underlying disease (20 leukemia, 10 lymphoma, 30 solid tumors). In a univariate analysis (EPI INFO 21 statistical package) and multivariate analysis (STATADV 33 computerised package), significant risk factors for AB bacteremia in cancer patients in comparison to all patients from the nationwide survey were neutropenia (p≤0.0001), prior receipt of antineoplastic (p≤0.001), and prior antimicrobial chemotherapy (p≤0.0006) in univariate, but only prior antimicrobial chemotherapy or prophylaxis in the multivariate logistic regression model (p≤0.01; CI 1.2–6.8; RR 2.06) (Table 1). Vice versa, wound infection, prior surgery, and decubital ulcers (p≤0.004–0.0001) as well as ventilatory support were less frequently observed. However, mortality due to cancer (33.9% and 32.9%) was comparable for all of the patients studied within the survey. Concerning the antimicrobial susceptibility of AB isolates from cancer patients, resistance to meropenem among bloodstream isolates in cancer patients was 16%, 30%to cefepime, 42%to ceftazidime, 27.5% to amikacin, 48% to piperacillintazobactam, 30% to cefoperazonsulbactam, 34% to ciprofloxacin, and 52% to aztreonam. Comparing the resistance rates of AB isolates from cancer vs other patients, resistance to ceftazidime (42% vs 24.5%; p≤0.01), piperacillin-tazobactam (72.8% vs 52%; p≤0.009), and aztreonam (52% vs 27.2%; p≤0.001) was significantly higher in cancer patients, probably because of the extensive use of ceftazidime (since 1985) and piperacillin-tazobactam (since 1992) in the empiric therapy of febrile neutropenia in 8 Slovak cancer centers. Support Care Cancer (2001) 9:558–559 DOI 10.1007/s005200100241 L E T T E R T O T H E E D I T O R

Mortality of Enterococcal Bacteremia: Are Inappropriately Treated Cases Associated with Higher Mortality?

2test was used to determine risk factors for death and comparisons of appropriate therapy versus inappropriate therapy. A multivariate logistic regression model (EPI INFO and STAT ADV computerized package of CDC and Postgraduate Medical School) was also used. Of 101 patients with enterococcal bacteremias, 40 died (39.9%). Predictors for inferior outcome identie ed in univariate analysis were 2 or more positive blood cultures ( pB0.0061), burns or decubital ulcer as underlying diseases ( pB0.004). The latter was the only predictor of death also in multivariate analysis ( pB 0.0006, OR 5.07 Cl (1.4‐ 18 5)). Surprisingly neutropenia and vascular catheters seemed to be protective in univariate analysis (pB0.0475 and pB0.0417, respectively). In multivariate analysis neutropenia was found to be signie cantly ( pB0.007) corrected to a lower mortality probably because of the use of early empirical therapy in neutropenia patients. In this subgroup of patients, death was 3.48 times less likely than in enterococcal bacteremia in non-neutropenic patients. We performed another univariate analysis comparing those who were appropriately treated ( nae81) versus inappropriately treated ( nae20, 19.9%) for enterococcal bacteremia. Both groups were comparable except in 6 of 36 risk factors. Only endocarditis ( pB0.0026) and 2 positive blood cultures (pB0.0267) were more frequently observed in inappropriately treated patients. Appropriate treatment was signie cantly more common in patients with cancer ( pB0.0165) and cytotoxic chemotherapy ( pB0.0147). In summary both analyses showed, that inappropriate therapy (either late therapy of drugs ineffective against enterococci) were associated with higher mortality, in patients with febrile neutropenia, fungaemia and endocarditis (1‐ 3). Vancomycin or other antibiotic resistance in enterococci was however, not associated with higher mortality.