UICC World Cancer Congress 2006

Objective: Blood stream infections (bacteremia) among cancer patients that develop during the course of disease are potentially life threatening because of suppression in their immune systems. The changing spectrum in the incidence and epidemiology of microbial pathogens, prevalence of antibiotic resistance in these strains was studied. Methods:Susceptibility pattern of 180 bacterial isolates from positive blood cultures collected during 2001-2004 was studied. The isolated strains were tested against cephalosporins, aminoglycosides, fluoroquinolones. The antibacterial susceptibility was determined by the minimal inhibitory concentration (MIC) by broth dilution method according to National Committee for Clinical laboratory standards (NCCLS) recommendations.. Results: Among gram negative bacteria , the overall respective MICs at which 50% and 90% of isolates inhibited (MIC50s and MIC90s; ug/mL) were ; ciprofloxacin, 4 and 8; ofloxacin, 16 & 64; pefloxacin, 16 &128; ceftazidime, 8 & 16 for P. aeruginosa 16 & 64 for enterobacteriaceae; Amikacin, 32& 128; Tobramycin, 4 & 64; Cefoperazone, 0.25 & 0.2; Ceftriaxone, 0.5 & 1; Ampicillin, 8 & 32 ug/mL respectively. MIC50 and MIC90 for P. aeruginosa against cefoperazone was, 0.125 & 0.25; Ceftriaxone, 1 &4; Ampicillin, 4 & 64ug/ml respectively. The susceptibity of gram negative bacteria to ciprofloxacin, ofloxacin and pefloxacin according to NCCLS susceptibility breakpoint was 20, 2 and 3% respectively. Similarly the resistance of gram negative bacterial isolates against flouroquinolones was sill higher. More than 90% of gram negative isolates were resistant against ceftazidime and cefuroxime whereas resistance to amikacin and tobramycin was 43% and 50% respectively. However, in gram positive bacteria much high resistance was observed against antibiotics used