Bacterial isolates from hematology, oncology, and intensive care units: Susceptibility to cefpirome and other beta-lactam antibiotics in a multicenter study in Mexico

Objective: An in vitro multicenter study mas conducted in 15 Mexican hospit als from September 1995 to May 1996 to provide data on the prevalence of ba cterial isolates from patients in hematology, oncology, and intensive care units, as well as data on the sensitivity of these organisms to cefpirome a nd other antimicrobial drugs commonly used in these units. Methods: Each participating center collected an average of 100 aerobic bact erial isolates from significant clinical specimens. Minimum inhibitory conc entrations to cefpirome and 7 other betalactam antibiotics commonly used em pirically to treat nosocomial infections in critically ill patients were de termined by the microdilution method. Results: The most frequent sources of the isolates were blood (37.1%), bron choalveolar lavage fluid (16.8%), skin or wounds (15.8%), and urine (14.0%) . The isolated bacteria mere distributed as follows: gram-negative enteric bacilli (40.8%), gram-negative nonenteric bacilli (88.8%), and gram-positiv e cocci (20.4%). Conclusions: Multiresistant gram-negative enteric and nonenteric bacilli me re the most important pathogens isolated in hospitalized, critically ill pa tients; however, gram-positive cocci (both staphylococcus and enterococcus) accounted for 20.4% of the isolates. Although the activity of cefpirome wa s similar or superior to that of the other antibiotics tested in this study , our results clearly stress the need for antimicrobial agents that are eff ective against infections caused by gram-negative and gram-positive bacteri a in critically ill patients.