Nosocomial infection in an Intensive Care Unit in a private hospital

The nosocomial infection rate in an Intensive care unit (ICU) of a private hospital was assessed during an 18-month survey. From 629 admissions to the ICU, 139 hospital-acquired infections were identified. The rate was 22.1 percent compared to the overall nosocomial infection rate of 15.3 percent for the entire hospital. In the ICU, the main infections occurred in the respiratory tract, 41 (29.5 percent), followed by surgical wounds, 35 (25.2 percent), urinary tract, 28 (20.1 percent) and the blood stream, 24 (17.3 percent). From 165 bacterial isolates, 80 percent of isolates were gram-negative rods, with P aeruginosa, 48 (36.6 percent), being the predominant gram-negative isolate followed by Klebsiella pneumoniae, 27 (20.6 percent), and Enterobacter sp, 22 (16.8 percent). The main gram-positive isolates were S aureus, 23 (41.8 percent), coagulase-negative Staphylococci, 17 (30.9 percent), and Enterococci, 11 (20.0 percent). Of the 23 S aureus strains, 15 (65.2 percent) were methicillin-resistant (MRSA), (8 MRSA were from surgical wounds, 5 from the respiratory tract and 2 from infected urine). Only 2 of the 17 (11.8 percent) coagulase-negative staphylococci were methicillin-resistant, and both were isolated from wounds. Resistance to ampicillin and augmentin (amoxicillin-clavulanic acid) was high, 81.9 percent and 55.4 percent, respectively. Gentamicin, azteronam, piperacillin-tazobactam showed resistance rates of less than 15 percent. Infection control measures aimed at reducing nosocomial infections at the hospital are often frustrated by apathy of hospital administrators who apparently are insensitive to the high nosocomial infection rate. Effort by the infection control team through seminars, lectures and newsletters have begun to show improvements in attitude and awareness of staff to infection control and preventative measures within the institution. (AU)

Prevalence of resistance to antimicrobials of Escherichia coli isolates from clinical sources at a private hospital in Trinidad

Antimicrobial susceptibility patterns of strains of Escherichia coli isolated between 1994 and 1998 were studied. Of the 1,283 strains examined, 75% were recovered from urine, 8.7% from wounds, 3.2% from blood, 2.6% from pus, and 10.5% from other sources. Isolates from inpatients and outpatients accounted for 46.1% and 53.9%, respectively. Gentamicin and nalidixic acid showed the greatest efficacy against isolates from both inpatients and outpatients, revealing a >90% sensitivity. Drugs with the lowest efficacies were ampicillin and amoxicillin-clavulanic acid, which showed a >45% resistance. Tetracycline showed a significant decline in resistance from 1994 to 1998 among strains from both inpatients and outpatients (P < 0.001). This decline may be related to a policy of restrictive antibiotic reporting by the Microbiology Laboratory and seminars for general practitioners, subsequent to an island-wide survey an antibiotic resistance. A similar pattern of declining resistance was also observed for cefuroxime. E. coli sensitivity to co-trimoxazole was relatively stable during the study period. Although the overall prevalence of resistance among E. coli strains is relatively low, on-going surveillance of bacterial resistance must continue. The microbial antibiogram can provide general practitioners and clinicians with data essential for optimum empiric choices. Further, the introduction of a policy of restrictive reporting may act "synergistically" with the education of doctors on resistance patterns, to effect island-wide reduction of antimicrobial resistance.

Methicillin resistance among Trinidadian isolates of community and hospital strains of Staphylococcus aureus and their patterns of resistance to non-beta-lactam antibiotics

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) strains in Trinidad and the extent of their resistance to other antimicrobial agents in hospital-acquired infections were evaluated over a 2-year period. A total of 450 S. aureus strains were isolated from different patients. The prevalence of methicillin resistance among S. aureus strains was 9.8 percent (44/450). The proportion of MRSA isolated from hospital sources and community sources was 12.5 percent (38/305) and 4.1 percent (6/145) respectively (P<0.05). The resistant rates of MRSA to the non-beta-lactam antibodies were as follows: 93.2 percent resistance to tetracycline, 68.2 percent to erythromycin, 61.4 percent to gentamicin, 45.5 percent to co-trimoxazole, and 20.5 percent to ciprofloxacin. No MRSA resistant to vancomycin was observed in this study. Study results showed significant increases in MRSA in hospital, 2 percent in 1995 to 12.5 percent in 1998 (P<0.05), and community, 0 percent in 1995 to 4.1 percent in 1998 (P<0.05). It has become apparent that infection must be focussed now on the community in order to monitor and limit the spread of this new and expanding reservoir of MRSA. (AU)

Methicillin resistance among Trinidadian isolates of community and hospital strains of Staphylococcus aureus and their patterns of resistance to non-beta-lactam antibiotics

The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) strains in Trinidad and the extent of their resistance to other antimicrobial agents in hospital-acquired and community-acquired infections were evaluated over a 2-year period. A total of 450 S. aureus strains were isolated from different patients. The prevalence of methicillin resistance among S. aureus strains was 9.8% (44/450). The proportion of MRSA isolated from hospital sources and community sources was 12.5% (38/305) and 4.1% (6/145), respectively (P < 0.05). The resistant rates of MRSA to the non-beta-lactam antibiotics were as follows: 93.2% resistance to tetracycline, 68.2% to erythromycin, 61.4% to gentamicin, 45.5% to co-trimoxazole, and 20.5% to ciprofloxacin. No MRSA resistant to vancomycin was observed in this study. Study results showed significant increases in MRSA in hospital, 2% in 1995 to 12.5% in 1998 (P < 0.05), and community, 0% in 1995 to 4.1% in 1998 (P < 0.05). It has become apparent that infection control and surveillance initiatives must be focused now on the community in order to monitor and limit the spread of this new and expanding reservoir of MRSA.

Methicillin resistant Staphylococcus aureus

The prevalence of methicillin resistant Staphylococcus aureus (MRSA) at the General Hospital, Port-of-Spain, between June 1995 and May 1996 was determined. The MRSA prevalence rate was 4.6 percent of all S aureus isolates, with all but one nosocomially acquired. 15 isolates were associated with infections, and three were colonizing strains. 17 of the 18 patients with MRSA had received antibiotics previously, including 13 who had received multiple antibiotics. Skin and soft tissue were the sites of infection and colonization in 12 cases; and surgical wards and the Intensive Care Unit (ICU) accounted for 16 MRSA isolates. All isolates were sensitive to vancomycin and all but one were resistant to gentamicin. MRSA occurred sporadically in a wide distribution of wards and physicians' services, although the isolation of three strains from the ICU and three strains from a surgical ward were temporally related. Only one of two deaths was attributable to MRSA. Control of the spread of MRSA in this hospital must include the reinforcement of the appropriate use of antibiotics, hand washing and appropriate isolation of patients in the surgical and intensive care wards.(Au)

Peritonitis in acute peritoneal dialysis at the University Hospital of the West Indies: a five-year review

The records of patients receiving acute peritoneal dialysis during the 1983 - 1987 were retrospectively evaluated. Of a total of 59 patients receiving dialysis, 10 developed peritonitis. Staphylococcus aureus was the single most frequently isolated organism. However, gram-negative bacilli as a group were more common. We recommend the use of cloxacillin orally and gentamicin intra-peritoneally as empiric antibiotic coverage until results of culture reports are available (AU)

Effacement of glomerular foot processes in kwashiorkor

In a study of the pathogenesis of the oedema of kwashiorkor the ultrastructure of the kidneys from 6 children was examined shortly after they died from oedematous malnutrition. There was a generalised effacement of the glomerular epithelial cells onto the basement membrane. The filtration slits that remained were narrowed. The picture was similar to that seen in minimal-change nephrotic syndrome-but none of the children had albuminuria. The degree of effacement was statistically related to treatment with gentamicin. The findings suggest that there is a defect in the anionic charge of the glomerular basement membrane in oedematous malnutrition, that the membrane charge is more easily neutralised by cations such as gentamicin, and that, because proteinuria is not a feature of oedematous malnutrition, the proteinuria in other conditions associated with glomerular epithelial cell effacement (eg, minimal-change nephrotic syndrome) is due to something more complex than simple loss of charge.(AU)

Microorganisms encountered in blood cultures at the Queen Elizabeth Hospital and their antibiotic sensitivity pattern

The importance of blood cultures in the early detection of organisms is examined with the following conclusions. The isolation of of gram-positive and gram negative organisms are isolated from blood cultures with equal frequency. K. pneumoniae and E. coli are the most frequently isolated gram gram-negataive organisms. Staph, epidermis is isolated more frequently than Stap. aureus. Gentamcin was found to be the most effective antibiotic against Gram-negative blood culture isolates. Clindamycin and cloxacillin were found to be the most effective antibiotics against the gram-positive isolates. Chloramphenicol was found to be the most effective agent against the anaerobes as a group