E. coli, K. pneumoniae and K. oxytoca community-acquired infections susceptibility to cephalosporins and other antimicrobials in Lebanon.

OBJECTIVES: Cephalosporin resistance in Enterobacteriaceae has become an international concern. This article studies the distribution and trends of resistance of E. coli and Klebsiella species isolated from clinical specimens representing community-acquired infections. METHODS: E. coli, K. pneumoniae and K. oxytoca specimen strains were collected from patients presenting to three acute care hospitals in Lebanon. The study period extended from January 2010 to January 2011 and included patients presenting with community-acquired infections only. Automated microbiological system (VITEK 2) was used for identification and antimicrobial susceptibilities. RESULTS: Data from consecutive non-duplicate 589 E. coli, 54 K. pneumoniae and 40 K. oxytoca strains were collected of which 69.5%, 74.0% and 67.5% were susceptible to 3rd generation cephalosporins (3GC), respectively. Out of the 3GC-resistant E. coli strains, around 90% were susceptible to nitrofurantoin, 46% were susceptible to trimethoprim/sulfamethoxazole (TMP/SMX) and 53% to ciprofloxacin. The patterns of antimicrobial susceptibility in the two Klebsiella species did not parallel those in the E. coli strains. Yet, the number of Klebsiella strains was much lower than that of E. coli. Of note is that the 3GC-resistant strains of both Klebsiella species were less susceptible to nitrofurantoin compared to the overall groups reaching a maximum of 30%. However, susceptibility to TMP/SMX was much higher reaching 79% and that of ciprofloxacin reaching 86%. CONCLUSION: Clinical specimens of E. coli, Klebsiella pneumoniae and Klebsiella oxytoca, causing community-acquired infections in Lebanon showed that these organisms are significantly resistant to many antibiotics. These patterns of resistance were mainly to internationally recommended drugs for empiric treatment of community-acquired infections like community-acquired urinary tract infections (UTIs) and intra-abdominal infections. Therefore, continuous antimicrobial susceptibility surveillance is advisable to track emerging resistance in Enterobacteriaceae and national guidelines would be tailored accordingly.

Characteristics and outcomes of methicillin-resistant Staphylococcus aureus surgical-site infections in patients with cancer: a case-control study.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) infections remain a significant cause of morbidity and mortality. We experienced an increased incidence of MRSA surgical-site infections (MRSA SSIs) at our institution. However, to our knowledge, no studies have evaluated the risk factors and outcomes of MRSA SSIs in cancer patients. METHODS: We conducted a case-control study and identified all patients who had developed MRSA SSIs at our institution from July 1, 2002 to July 30, 2003, and all patients who had undergone surgery by the same surgical team during the same time period but who had not developed MRSA SSIs. Cases and controls were age-matched at 1:2 ratio. RESULTS: The study included 29 cases and 58 controls. Mean interval between surgery and MRSA SSI onset was 17.8 days (range 3-75 days). Cases were more likely than controls to have progressive cancer (72 versus 38%), have received antibiotics (mainly quinolones) within 24 h of surgery (17 versus 2%), have had ongoing infection (10 versus 0%), and have had longer hospital and intensive care unit stays (11.0 versus 7.8 days and 3.4 versus 1.5 days) (all P < 0.05). In a multivariate logistic regression analysis, significant predictors of MRSA SSI in cancer patients were antibiotics use <24 h of surgery and progressive cancer. No surgical factors (i.e., procedure time or timing of perioperative antibiotics) were associated with increased risk of MRSA SSI. CONCLUSIONS: Several clinical and postoperative factors were associated with increased risk of MRSA SSI in cancer patients, but antibiotic use before surgery (especially quinolones) and progressive cancer were the only independent predictors.

Amphotericin B lipid complex versus liposomal amphotericin B monotherapy for invasive aspergillosis in patients with hematologic malignancy.

BACKGROUND: Invasive aspergillosis (IA) is a major cause of morbidity and mortality in patients with hematologic malignancy (HM). There are 2 lipid formulations of amphotericin B (AMB) currently in widespread use: AMB lipid complex (ABLC) and liposomal AMB (L-AMB). There are limited data comparing the efficacy and safety of these 2 agents in the treatment of IA in patients with cancer. METHODS: The authors retrospectively studied 381 consecutive patients with HM who had proven or probable IA (according to European Organization for Research and Treatment of Cancer/Mycosis Study Group of the National Institute of Allergy and Infectious Diseases criteria) between June 1993 and December 2005. Of these patients, 158 received primary antifungal therapy with either L-AMB (n=106) or ABLC (n=52). The number of salvage antifungal regimens given were 51 L-AMB regimens and 30 ABLC regimens. It should be noted that the population described in this report was not typical of the hematologic cancer population with IA because of the advanced stage and the severity of the underlying diseases. RESULTS: Risk factors for IA, such as underlying malignancy, neutropenia, steroid use, admission to an intensive care unit, and the presence of graft-versus-host disease, were comparable among the study drug group in the primary or salvage setting. Likewise, comparable distribution of types of Aspergillus species and the presence of disseminated IA were observed. Response to primary or salvage therapy was equally poor in both drug study groups regardless of treatment modality (range, 7.7-15.8% response). In the primary therapy group, ABLC was associated with significantly higher nephrotoxicity than L-AMB (P<.001). CONCLUSIONS: Among patients with HM, primary therapy and salvage therapy for IA with either ABLC or L-AMB as single agent were associated equally with poor outcome. L-AMB appeared to be less nephrotoxic in the primary therapy setting.