Microbial Isolates in Diabetic Foot Lesions of Hospitalized Patients at the University Hospital of the West Indies

ABSTRACT Objective: The diabetic foot is a frequent complication of diabetes mellitus. It confers a negative impact on the patients' quality of life and profound burden on the healthcare system. The objectives of this study were to determine the bacteriological profile and antibiotic susceptibility of patients admitted to the University Hospital of the West Indies with diabetic foot ulcer over a 5-year period, and whether methicillin-resistant Staphylococcus aureus is a common microbial isolate and if antibiotic resistance played a role on the patients' duration of hospital stay or amputation. Methods: A retrospective analysis was done on the patients admitted from January 2003 to December 2008 with the diagnosis of diabetes mellitus and foot complications. The eligible patients and their medical records were identified by the medical records department. Their demographic data, types of cultures done and results, antibiotic susceptibility and resistance, and treatment regimens were all recorded. Frequency and means were calculated, and statistically significant covariates used as the predictors in univariate and multivariate regression models. Results: Of the 545 cases admitted, 102 had complete data for analysis. Group D Streptococci was the most common organism isolated (45.1%) followed by other forms of Streptococci and Pseudomonas aeruginosa. The majority of cases (80.6%) had two or more bacterial isolates. Gram-negative bacteria (Proteus and Klebsiella) and anaerobes were also common, 48.0% and 22.5% respectively. There were no cases of methicillin-resistant Staphylococcus aureus. Antibiotic resistance was not significant. Conclusion: Gram-positive organisms, especially the Streptococcus species, remain an important organism in diabetic foot infections. Current empiric antibiotic regimes used are effective in this tertiary care university hospital.

Microbial isolates from patients in an intensive care unit, and associated risk factors / Aislados microbianos de pacientes en una unidad de cuidados intensivos, y factores de riesgos asociados

A retrospective one-year analysis of blood, sputum and urine samples taken from all patients admitted for more than 48 hours to the Intensive Care Unit at the University Hospital of the West Indies (UHWI) was undertaken. Positive trapped sputum cultures were found in 50of patients, positive blood cultures in 32.7and positive urine cultures in 23.1. Gram-negative organisms predominated especially Pseudomonas aeruginosa (41.3) and Acinetobacter spp (33.5). Coagulase-negative staphylococcus (20) and streptococcus group D (18.7) were the most common gram-positive organisms. The Acinetobacter spp showed marked resistance to most antibiotics except for meropenem (82.7susceptibility) while P. aeruginosa was most susceptible to ceftazidime (84.4) and amikacin (89.1). Both the coagulase-negative staphylococcus and streptococcus group D were relatively sensitive to amoxycillin/clavulanate (80.6and 79.3respectively). There was a high incidence of yeast found in sputum (27.1) and urine (16.8). Mechanical ventilation was a significant risk factor for developing a positive sputum culture (p = 0.01), this effect being particularly prominent in those ventilated for > 5 days. Central venous pressure lines significantly increased the risk of a positive blood culture (p = 0.005). This increase was seen particularly in those with CVP lines for > 7 days. Other risk factors for developing positive cultures included preadmission infection, antibiotic use just prior to ICU admission, increasing APACHE II score and increasing age.

Un análisis retrospectivo de muestras de sangre, esputo y orina tomadas a todos los pacientes ingresados por más de 48 horas en la Unidad de Cuidados Intensivos del Hospital Universitario de West Indies (HUWI) fue realizado por espacio de un año. Se hallaron cultivos de esputo positivos en 50% de los pacientes, cultivos de sangre positivos en el 32.7%, y cultivos de orina positivos en el 23.1%. Hubo predominio de organismos gram-negativos, en especial Pseudomonas aeruginosa (41.3%) y Acinetobacter spp (33.5%). Los estafilococos coagulasa-negativos (20%) y los estreptococos del grupo D (18.7%) fueron los organismos gram-positivos más comunes. Los Acinetobacter spp mostraron marcada resistencia a la mayoría de los antibióticos, salvo al meropenem (82.7% susceptibilidad), mientras P aeruginosa fue muy susceptible a la ceftazidima (84.4%) y a la amikacina (89.1%). Tanto el estafilococo coagulasa-negativo como el estreptococo del grupo D fueron relativamente sensibles a la amoxicilina/clavulanato (80.6% y 79.3% respectivamente). Se halló una alta incidencia de levadura en el esputo (27.1%) y la orina (16.8%). La ventilación mecánica fue un factor de riesgo importante para desarrollar un cultivo de esputo positivo (p = 0.01), siendo este efecto particularmente prominente en los ventilados por > 5 días. Las líneas de la presión venosa central aumentaron significativamente el riesgo de un cultivo de sangre positivo (p = 0.005), haciéndose este incremento particularmente evidente en aquellos con líneas de PVC por > 7 días. Otros factores de riesgo para el desarrollo de cultivos positivos incluyeron las infecciones previas a la admisión, el uso de antibióticos justo antes del ingreso a la UCI, el aumento de la puntuación APACHE II cuenta, y la edad avanzada.

Extended spectrum beta-lactamase producing organisms at the University Hospital of the West Indies

Extended spectrum beta-lactamases (ESBL) represent a major group of beta-lactamases that have the ability to inactivate beta-lactam antibiotics containing an oxyimino group such as third generation cephalosporins and monobactams. These enzymes are produced by gram negative organisms, especially members of the Enterobacteriaceae family such as Klebsiella pneumoniae and Escherichia coli. The prevalence of these organisms varies widely internationally, as well as within the same country. This is the first study on ESBL production in K pneumoniae and E coli at the University Hospital of the West Indies, a tertiary care hospital in Jamaica. Two-hundred and sixty-four isolates of K pneumoniae and 300 isolates of E coli were collected over the study period January 2002 to December 2002. Forty-eight (18.2) K pneumoniae isolates were confirmed to be ESBL producers, while there was no ESBL producing E coli. Infections with ESBL producing organisms can pose a therapeutic challenge, leading to treatment failure if the wrong class of antibiotics is used. With increasing resistance to all classes of antibiotics, there is a narrowing of available treatment options. It is very important that these organisms be monitored and antibiotic policies as well as infection control policies be in place to curtail their spread

The medical management of diabetes mellitus with particular reference to the lower extremity: the Jamaican experience

Predisposing factors for the diabetic foot include peripheral neuropathy, peripheral vascular disease (PVD), hyperglycaemia and increased duration of diabetes. From the records of patients admitted to the University Hospital of the West Indies with the diabetic foot, we reviewed the results of the microbiology of wound swabs from diabetic foot ulcers. We noted the high prevalence of P VD (66.6), peripheral neuropathy (50), hyperglycaemia (75.6) and increased duration of diabetes (17.5 years). A history of past foot ulcers was common and 87.2had polymicrobial infection. The commonest organisms were gram positive organisms which were usually sensitive to the 2 antibiotic regimes that were commonly used. Euglycaemia, a favourable lipid profile, control of blood pressure, yearly foot examination and institution of measures to prevent foot trauma are important in the prevention of foot ulceration.