Distribution of virulence determinants among antimicrobial-resistant and antimicrobial-susceptible Escherichia coli implicated in urinary tract infections.

INTRODUCTION: Uropathogenic Escherichia coli (UPEC) rely on the correlation of virulence expression with antimicrobial resistance to persist and cause severe urinary tract infections (UTIs). OBJECTIVES: We assessed the virulence pattern and prevalence among UPEC strains susceptible and resistant to multiple antimicrobial classes. METHODS: A total of 174 non-duplicate UPEC strains from patients with clinically significant UTIs were analysed for susceptibility to aminoglycoside, antifolate, cephalosporin, nitrofuran and quinolone antibiotics for the production of extended-spectrum ß-lactamases and for the presence of six virulence determinants encoding adhesins (afimbrial, Type 1 fimbriae, P and S-fimbriae) and toxins (cytotoxic necrotising factor and haemolysin). RESULTS: Relatively high resistance rates to nalidixic acid, ciprofloxacin, cephalothin and trimethoprim-sulfamethoxazole (82%, 78%, 62% and 59%, respectively) were observed. Fourteen distinct patterns were identified for the virulence determinants such as afaBC, cnfI, fimH, hylA, papEF and sfaDE. The toxin gene, cnfI (75.3%), was the second most prevalent marker to the adhesin, fimH (97.1%). The significant association of sfaDE/hylA (P < 0.01) among antimicrobial resistant and susceptible strains was also observed notwithstanding an overall greater occurrence of virulence factors among the latter. CONCLUSIONS: This study provides a snapshot of UPEC complexity in Jamaica and highlights the significant clonal heterogeneity among strains. Such outcomes emphasise the need for evidence-based strategies in the effective management and control of UTIs.

Beta Cell Regenerating Potential of Azadirachta indica (Neem) Extract in Diabetic Rats.

OBJECTIVE: This study evaluated the ability of 0.8% neem leaf extract (NLE) to treat diabetes mellitus by assessing its effects on blood glucose, insulin levels and islet morphology in streptozotocin (STZ)-induced diabetic Sprague-Dawley rats. METHODS: Diabetes was induced in two to three-day old rat pups by STZ intraperitoneally (60 mg/kg), followed by a further 40 mg/kg dose 12-23 weeks later. The diabetic treated (DT) rats received 0.8% w/v NLE in tap water while diabetic control (DC) and normal control (NC) rats received water ad libitum. Body weight, water and chow consumption, and blood glucose were evaluated weekly. Blood and pancreas were collected at the end of the study to evaluate serum insulin and islet histology, respectively. RESULTS: Neem leaf extract (0.8%) improved weight gain and beta cell regeneration but did not reduce blood glucose. Serum insulin increased slightly in the treated group and three-fold in the DC group (p < 0.05). CONCLUSION: The results suggest that NLE has beta cell regenerating potential.

Comparison of antibiotic resistance and virulence factors in pigmented and non-pigmented Pseudomonas aeruginosa.

OBJECTIVE: Pseudomonas aeruginosa produces multiple virulence factors that have been implicated in pathogenesis and quorum sensing. The aim of this study was to determine differences in the virulence factors of pigmented and non-pigmented P aeruginosa isolates. METHODS: Associations were assessed between pigment production (pyocyanin and pyoverdin) and production of DNase, elastase, lipase, protease, siderophore, twitching motility, antibiotic resistance patterns and virulence-associated genes in 57 non-duplicate P aeruginosa isolates from wounds, sputum, urine, high vaginal swab (HVS), ear, eye and respiratory tract swabs and aspirates of peritoneum and ulcers. RESULTS: Most (82.5%) of the isolates produced either pigment. Pigmented isolates produced more frequently and significant more (p < 0.05) DNase, elastase, lipase protease, and siderophore. Imipenem was the only antibiotic to which all isolates were susceptible (p < 0.05), while 93% and 32% were resistant to tetracycline and norfloxacin, respectively. There was however no significant difference between pigmented and non-pigmented isolates when antibiotic resistance was compared. While isolates had multiple virulence-associated genes, exoS (51%), rhlA (37%) and rhlB (46%) were the predominant genes detected. Except for exoY, genes were present in pigmented isolates more frequently than in non-pigmented isolates. CONCLUSION: The results of this study suggest that antibiotic resistance per se might not be associated with the pigment production in P aeruginosa. However pigment production appeared to be more significantly associated with multi-drug resistance, presence of virulence-associated genes, and expression of certain virulence factors, most notably elastase, protease, siderophore and DNase activity. Since pigment production is easy to determine, this might to be a good starting point to identify the virulence status of an isolate.

Environmental risk factors associated with leptospirosis among butchers and their associates in Jamaica.

BACKGROUND: Leptospirosis, a spirochetal zoonosis, is considered an occupational disease of persons engaged in agriculture, sewage works, forestry, and butchery. OBJECTIVE: To determine the environmental sources and the knowledge, attitude and practices for leptospirosis among butchers and slaughterhouse workers, as well as the seroprevalence of leptospirosis among cattle and pigs presented for slaughter. METHODS: Using an interviewer administered questionnaire, all 110 butchers and other slaughterhouse workers in the parishes of Kingston and St. Andrew, Jamaica were surveyed. In addition, 179 blood samples from animals presented for slaughter were tested for anti-Leptospira antibodies using the microscopic agglutination test (MAT). RESULTS: Analyses indicated that people with the studied occupations are at risk for developing leptospirosis due to several environmental risk factors that exist in slaughterhouses. Among the risk factors, limited knowledge of the disease and its transmission, lower educational level attained, younger age and unhealthy behaviors (e.g., hand washing and improper or lack of use of personal protective gears), presence of stray dogs and rodents, and inadequate maintenance of physical plants, were found to be important. Of the total number of animal samples tested, 20 (11%) were positive. Canicola and Hardjo (among cattle) and Bratislava (among pigs) were the major seroreactors. CONCLUSION: Butchers and slaughterhouse workers engaged in animal handling and slaughtering could be frequently exposed to leptospirosis, and hence control strategies targeting at these populations should be implemented.

The emergence of qnr-mediated quinolone resistance among Enterobacteriaceae in Jamaica.

OBJECTIVE: Quinolone resistance is usually caused by various chromosomal mutations, but has been more recently associated with plasmids which carry the qnr determinant. The aim of this study is to investigate the prevalence of qnr genes in clinical isolates of Enterobacteriaceae in Jamaica. METHODS: A total of 255 non-duplicate fluoroquinolone-resistant Enterobacteriaceae clinical isolates, comprising 232 Escherichia coli, 20 Klebsiella species and three Enterobacter spp were collected between October 2007 and November 2008 from hospitalized patients in Jamaica. The presence of the qnr gene was screened by PCR using specific primers for qnrA, qnrB and qnrS in extracted plasmid DNA. RESULTS: Eighty-three (32.5%) of these isolates were qnr-positive, of which 47.0% housed the qnrA gene only, 1.2% qnrB and 9.6% qnrS only. Another 36.1% possessed both qnrA and qnrS genes. Approximately 30% of the quinolone-resistant E coli isolates harboured the qnr gene while 50% Klebsiella spp and all Enterobacter spp were positive. CONCLUSION: The emergence of qnr-mediated quinolone resistance among clinical Enterobacteriaceae isolates is described for the first time in Jamaica.

Clustering of cases of Mycobacterium fortuitum infection investigated by molecular typing.

Organisms of the Mycobacterium fortuitum complex are recognised but uncommon causes of pulmonary disease, primary cutaneous disease and a wide spectrum of nosocomial infections. M fortuitum was isolated from 20 patients over a 15 month period, with an apparent clustering of isolates occurring from January to March 1994. The molecular epidemiology of this clustering was investigated using an arbitrary primer polymerase chain reaction method (AP-PCR). 21 isolates were studied, which yielded 13 distinct profiles. Multiple isolates from a single patient yielded identical profiles. All of seven isolates recovered during the six week period from January to March 1994 shared a common profile which was distinct from all other isolates, suggesting that a single strain was isolated from specimens from all seven patients. The source of this cluster is uncertain. We can find no epidemiological basis for an episode of cross-infection within the hospital environment, and it is assumed that contamination of the specimens during collection, transport or processing was responsible for the "pseudo-outbreak" of M fortuitum.

Clustering of cases of Mycobacterium fortuitum infection investigated by molecular typing

Organisms of the Mycobacterium fortuitum complex are recognised but uncommon causes of pulmonary disease, primary cutaneous disease and a wide spectrum of nosocomial infections. M fortuitum was isolated from 20 patients over a 15 month period, with an apparent clustering of isolates occurring from January to March 1994. The molecular epidemiology of this clustering was investigated using an arbitrary primer polymerase chain reaction method (AP-PCR). 21 isolates were studied, which yielded 13 distinct profiles. Multiple isolates from a single patient yielded identical profiles. All of seven isolates recovered during the six week period from January to March 1994 shared a common profile which was distinct from all other isolates, suggesting that a single strain was isolated from specimens from all seven patients. The source of this cluster is uncertain. We can find no epidemiological basis for an episode of cross-infection within the hospital environment, and it is assumed that contamination of the specimens during collection, transport or processing was responsible for the [quot ]pseudo-outbreak[quot ] of M fortuitum.

Evaluation of the polymerase chain reaction for early diagnosis of leptospirosis.

Early diagnosis of leptospirosis is important because severe leptospiral infection can run a fulminant course. The polymerase chain reaction (PCR) was evaluated for the detection of leptospires in clinical samples from patients with acute leptospiral infection. Blood and urine samples from 71 patients with leptospirosis were examined by PCR, culture or serology. Samples from 44 (62%) patients with the diagnosis of leptospirosis were positive by PCR as compared to 34 (48%) by culture. The presence of leptospires was demonstrated by PCR in 13 patients before the development of antibodies, as well as in two patients who were seronegative during their illness and at autopsy. Samples from 16 patients without leptospirosis were seronegative and culture negative, and also negative by PCR. We conclude that PCR is a rapid, sensitive and specific means of diagnosing leptospiral infection, especially during the first few days of the disease.