Prevalence of Shigella serogroups and their antimicrobial resistance patterns in southern Trinidad.

The serogroup distribution and antimicrobial susceptibility patterns of Shigella isolates obtained from stool specimens of persons with acute diarrhoea in community-based studies from southern Trinidad during 1997-2006 were reviewed. Of the 5,187 stool specimens, 392 (8%) were positive for Shigella organisms. From these 392 isolates, 88.8% were recovered from children aged >0-10 year(s). Shigella sonnei was the most frequently-isolated serogroup (75%), followed by S. flexneri (19%), S. boydii (4.1%), and S. dysenteriae (1.8%). S. flexneri was the major isolate among the >20-30 years age-group. The most common drug resistance among all age-groups was to ampicillin. All strains of S. flexneri, S. boydii, and S. dysenteriae were fully susceptible to aztreonam, gentamicin, and ciprofloxacin. S. sonnei, the most common species isolated, showed resistance to all antibiotics tested. The data showed that, throughout the study period, the resistance to commonly-used drugs was relatively low. Since resistance to several drugs seems to be emerging, continuous monitoring of resistance patterns is mandatory for the appropriate selection of empiric antimicrobial drugs in the therapy of suspected cases of shigellosis.

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 Wiliams Sciences Complex (EWMSC) were reviewed. A total of 3,513 specimens were processed, 43.1 percent from in-patients and 56.9 percent from out-patients. Of the 3,513 specimens, 1,129 (32.1 percent) yielded positive cultures. Micro-organisms from wounds, sputum and genital tract accounted for 90.2 percent, 51.5 percent and 31.8 percent, respectively, of all isolates. E coli (17.4 percent) and Enterococci (12.2percent) were the predominant isolates and were also the major pathogens from blood stream infections, 25.8 percent and 18.2 percent, respectively, followed by P aeruginosa, 15.2 percent. 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 percent resistance in Acinetobacter spp, 15.2 percent in Enterobacter spp, 17.4 percent in Klebsiella spp.], erythromycin (no resistance in Enterobacter and Citrobacter spp, and 89.5 percent in Acinetobacter (spp), erythromycin (no resistance in Groups A and B streptococci, 85.1 percent in S aurens 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.

Socio-biological associations of bacteriuria in pregnancy

The prevalence and socio-biological relations of bacteriuria was found to be 16.7 per cent and it was more common in the 30-39 age group, among parous women, among negroes, and in patients with a low family income and overcrowded living conditions. Symptoms were present in 19 per cent of bacteriuric patients and almost one-third gave a past history of urinary tract infection. Only 10 per cent had been previously exposed to sexually transmitted diseases such as syphilis, gonorrhoea and herpetic genital infections. Because of the serious consequences to mother and foetus, we advocate quantitative urine cultures for all antenatal patients, especially those from disadvantaged socio-economic conditions

Campylobacter jejuni diarrhoea in humans

Campylobacter jejuni, a gram negative rod, is a common cause of acute bacterial diarrhoea. It is transmitted to humans from domestic animal and poultry reservoirs through contaminated water, milk and food. It affects all age groups but especially the young. The majority of patients have a mild self-limiting diarrhoeal illness which is often preceded by constitutional symptoms. Erythromycin is indicated in those more severely affected. Prevention consists of good hygienic practice in the preparation of food and after contact with animals, animal products and infected individuals