Prevalence of bacterial pathogens and susceptibility patterns from clinical sources in Trinidad

During a 12-month period (January-December, 1997), bacterial isolates of specimens from in-patients and out-patients of the Eric Williams Medical Sciences Complex (EWMSC) were reviewed. A total of 3,513 specimens were processed, 43.1% from in-patients and 56.9% from out-patients. Of the 3,513 specimens, 1129 (32.1%) yielded positive cultures. Micro-organisms from wounds, sputum and genital tract accounted for 90.2%, 51.5% and 31.8%, respectively, of all isolates. E coli (17.4%) and Enterococci (12.2%) were the predominant isolates and were also the major pathogens from blood stream infections, 25.8% and 18.2%, respectively, followed by P aeruginosa, 15.2%. High levels of resistance were seen to ampicillin, augmentin (amoxicillin-clavulanic acid) and tetracycline. The most effective antibiotics were ceftazidime (no resistance in E coli Citrobacter spp, non-typhoidal Salmonella and Group B streptococci, 63.2% resistance in Acinetobacter spp, 15.2% in Enterobacter spp, 17.4% in Klebsiella spp.], gentamicin [no resistance in Enterobacter and Citrobacter spp, and 89.5% in Acinetobacter spp), erythromycin (no resistance in Groups A and B streptococci, 85.1% in S aureus and S pneumoniae). The spectrum of isolates will provide clinicians with data on which to base their "best guess" aetiologic agent and choice of antibiotics when faced with infectious diseases in areas where laboratory assistance is not readily available.