Impact of Ceftazidime Use on Susceptibility Patterns in the Neonatal Intensive Care Unit.

BACKGROUND: Ceftazidime use in the neonatal intensive care unit (NICU) has increased after a cefotaxime shortage. The impact of this change is unknown. The purpose was to assess the effect of increased ceftazidime use on susceptibilities of Gram-negative organisms in the NICU. METHODS: Retrospective study of Gram-negative isolates identified in blood, urine, cerebrospinal fluid, tracheostomy, abdominal fluid and pleural fluid cultures from a single-center NICU over a 5-year period. Duplicate cultures that occurred within 90 days were noted. Pre- and postshortage periods were defined based on cessation of cefotaxime. Third- and fourth-generation cephalosporin susceptibility rates were compared between periods, as well as rates of extended-spectrum beta-lactamase (ESBL) Escherichia coli and Klebsiella species. RESULTS: Analysis included 666 isolates. Twelve (1.8%) were duplicate isolates that occurred after a 90-day period. The preshortage period included 464 (69.7%) isolates, and the postshortage included 202 (30.3%). No significant differences in susceptibility rates were noted when excluding duplicates. No difference in ESBL rates for E. coli were noted between periods (3.8% vs. 4.9%, P =1.000). No ESBL-positive Klebsiella species were identified. A post-hoc analysis of duplicate isolates demonstrated significant lower susceptibility rates for Pseudomonas aeruginosa to ceftazidime (risk ratio 0.58; 95% CI: 0.43-0.79) and cefepime (risk ratio 0.66; 95% CI: 0.51-0.86). CONCLUSIONS: Ceftazidime use did not appear to affect susceptibility rates for third- and fourth-generation cephalosporins for most Gram-negative organisms in the short-term of 1.5 years. However, susceptibility rates for P. aeruginosa decreased when evaluating duplicate isolates. Long-term monitoring is needed to assess the true impact.

Prevalence and antimicrobial susceptibility of bacterial pathogens isolated from urine specimens received in rizgary hospital - Erbil.

BACKGROUND: Urinary tract infection (UTI) is a common health-associated problem worldwide. Like other medical conditions, UTI patients may suffer from poor treatment outcomes due to the emergence of antimicrobial resistance. Determining patterns of antimicrobial susceptibility in uropathogens will guide physicians to choose the best antibiotics for treating affected patients. In this project we aimed to evaluate the frequencies of pathogens associated with UTI and their antimicrobial susceptibility patterns. METHODS: This study was conducted on 2692 urine samples of patients visited Rizgary Teaching Hospital in Erbil city. Aerobic bacterial growth identification and antimicrobial susceptibility tests were performed using VITEK®2 compact system. RESULTS: Our data show that more than 20% of all studied samples were negative for bacterial growth; only 16.72% of them were pathogenic bacteria in which 82.44% of them were Gram negative bacteria (GNB) and the rest were Gram positive bacteria (GPB). Escherichia coli was the most frequent, and Acinetobacter baumannii was the most resistant GNB. Staphylococcus haemolyticus was the most frequent, and Enterococcus faecalis was the most resistant GPB. In general GNB were highly resistant to Ticarcillin and Cefepime, and GPB were also resistant to Ticarcillin, and Tigecycline antibiotics. CONCLUSIONS: The amount of negative culture growth indicates that symptoms only based diagnosis for UTI detection is unreliable. E. coli is the most UTI related pathogen, E. faecalis and A. baumannii were among highly antibiotic resistant bacteria. Finally, since many of GNG and GPB isolates were resistant to several antibiotics, there might be a high possibility for multi drug resistant among local population in Erbil.

Urine flow cytometry is an adequate screening tool for urinary tract infections in children.

Diagnosing a urinary tract infection in children is often difficult due to non-specific symptoms and requires invasive and time-consuming procedures. Flow cytometry is a new and rapid method of analyzing urine to confirm or exclude UTIs. We have investigated the sensitivity and specificity of urine flow cytometry (Sysmex UF1000i) compared to conventional diagnostic techniques in a prospective study from January 1, 2014 until January 1, 2015. All children under 13 years of age with a suspicion of urinary tract infection were screened using both urine flow cytometry and urine culture. A urinary tract infection was defined as the combination of leukocyturia (≥ 25 leukocytes per µl) and a positive urine culture in the presence of clinical symptoms. A total number of 412 urine samples were collected, of which 63 cases (15.3%) were positive for a urinary tract infection. Receiver operating characteristic analysis showed an area under the curve of 0.97 (95% confidence interval h0.93-1.00) for the bacterial count. When using a cut-off value of 250 bacteria/µl in the presence of leukocyturia, the sensitivity for urinary tract infection is 0.97 with a negative predictive value of 97%, and the specificity is 0.91 with a positive predictive value of 90%.Conclusion: Flow cytometry-based bacterial and leukocyte count analysis is a time-efficient method of diagnosing or ruling out urinary tract infection in children, with a higher sensitivity and specificity than dipstick and microscopic analysis. What is known • Screening for urinary tract infections in children is difficult due to invasive and time-consuming procedures. • There is both over- and under-treatment of urinary tract infections due to the delays in accurate diagnosing. What is new • Flow cytometry is a rapid and accurate method to provide useful information in the diagnosis of urinary tract infection in children. When negative, flow cytometry can exclude urinary tract infection in children with a high degree of confidence. When flow cytometry is positive, the possibility of a urinary tract infection in children is increased.

Identification of Leptospira and Bartonella among rodents collected across a habitat disturbance gradient along the Inter-Oceanic Highway in the southern Amazon Basin of Peru.

BACKGROUND: The southern Amazon Basin in the Madre de Dios region of Peru has undergone rapid deforestation and habitat disruption, leading to an unknown zoonotic risk to the growing communities in the area. METHODOLOGY/PRINCIPAL FINDINGS: We surveyed the prevalence of rodent-borne Leptospira and Bartonella, as well as potential environmental sources of human exposure to Leptospira, in 4 communities along the Inter-Oceanic Highway in Madre de Dios. During the rainy and dry seasons of 2014-2015, we captured a total of 97 rodents representing 8 genera in areas that had experienced different degrees of habitat disturbance. Primarily by using 16S metagenomic sequencing, we found that most of the rodents (78%) tested positive for Bartonella, whereas 24% were positive for Leptospira; however, the patterns differed across seasons and the extent of habitat disruption. A high prevalence of Bartonella was identified in animals captured across both trapping seasons (72%-83%) and the relative abundance was correlated with increasing level of land disturbance. Leptospira-positive animals were more than twice as prevalent during the rainy season (37%) as during the dry season (14%). A seasonal fluctuation across the rainy, dry, and mid seasons was also apparent in environmental samples tested for Leptospira (range, 55%-89% of samples testing positive), and there was a high prevalence of this bacteria across all sites that were sampled in the communities. CONCLUSIONS/SIGNIFICANCE: These data indicate the need for increased awareness of rodent-borne disease and the potential for environmental spread along the communities in areas undergoing significant land-use change.

Increased resistance of gram-negative urinary pathogens after kidney transplantation.

BACKGROUND: Urinary tract infection is the most common complication after kidney transplantation. It can cause severe sepsis and transplant loss. Emergence of drug resistance among gram-negative urinary pathogens is the current challenge for urinary tract infection treatment after kidney transplantation. METHODS: This study analyzes the antimicrobial susceptibility of gram-negative urinary pathogens after kidney transplantation from 2009 to 2012 at the Transplant Outpatient Clinic of the University Hospital Essen, Germany. Kidney transplant patients at the University Hospital Essen receive regular follow up examinations after transplantation. Midstream urines were examined for bacteriuria at each follow up visit. RESULTS: From 2009 to 2012 15.741 urine samples were obtained from 859 patients. In 2985 (19%) samples bacterial growth was detected. The most frequently detected gram-negative bacteria were E.coli 1109 (37%), Klebsiella spp. 242 (8%) and Pseudomonas aeruginosa 136 (4.5%). Klebsiella spp. showed a significant increase of resistance to trimethoprim-sulfamethoxazole by 19% (p = 0.02), ciprofloxacin by 15% (p = 0.01) and ceftazidime by 17% (p = 0.004). E.coli and P. aeruginosa isolates presented no significant differences of antimicrobial susceptibility to the analyzed antibiotics. CONCLUSIONS: Antimicrobial resistance of Klebsiella spp. increased significant to trimethoprim-sulfamethoxazole, ciprofloxacin and ceftazidime from 2009 to 2012.

Pitfalls of diagnosing urinary tract infection in infants and young children.

BACKGROUND: The aim of this study was to examine the sensitivity and specificity of pyuria-based diagnosis of urinary tract infection (UTI) in urine collected by transurethral catheterization, and the reliability of diagnosis of pyuria in urine collected in a perineal bag. The gold standard for UTI diagnosis is significant colony counts of a single organism in urine obtained in a sterile manner. METHODS: We enrolled 301 patients who underwent medical examination at the present hospital for possible UTI between January 2005 and December 2009. We collected 438 urine samples by transurethral catheterization. We investigated the accuracy of pyuria-based diagnosis of UTI using transurethral catheterization urine specimens, and the reliability of diagnosis of pyuria using bag-collected urine specimens. RESULTS: The false-negative rate of UTI diagnosis based on pyuria in transurethral catheterization urine sediments was 9.0%; there was no significant difference in the false-negative rate of UTI diagnosis between boys and girls. Approximately 28% of pyuria-positive bag-collected urine specimens were pyuria negative on transurethral catheterization; this rate was significantly higher in girls than in boys (56.7% vs. 8.9%, P < 0.0001). CONCLUSIONS: The absence of pyuria in transurethral catheterization urine sediments does not rule out UTI. Pyuria in bag-collected urine specimens frequently consists of urine leukocytes from external genitalia as well as from the urinary tract.

Extended spectrum beta lactamase (ESBL) producing bacteria urinary tract infections and complex pediatric urology.

AIM OF THE STUDY: Extended spectrum beta lactamase (ESBL) producing bacteria are resistant to most beta-lactam antibiotics including third-generation cephalosporins, quinolones and aminoglycosides. This resistance is plasmid-borne and can spread between species. Management of ESBL is challenging in children with recurrent urinary tract infections (UTIs) and complex urological abnormalities. We aim to quantify the risk in children and specifically in urological patients. METHODS: Retrospective review of a microbiology database (April 2014 to November 2015). This identified urine isolates, pyuria, ESBL growth and patient demographics. Data analysis was by Chi square, Mann-Whitney U-test and ANOVA. A P value of <0.05 was taken as significant. MAIN RESULTS: Analysis of 9418 urine samples showed 2619 with pure isolates, of which 1577 had pyuria (>10×106 WC/L). 136 urine cultures (n=79 patients) grew purely ESBL. Overall, 5.2% of urine isolates were ESBL and 9.5% isolates with pyuria (>100×106 WC/L) had ESBL, whereas only 22/1032 (2.1%) with no pyuria, (P<0.0001). Urology patients had 86/136 (63%) ESBL positive cultures. These represented 86/315 (27%) of all positive cultures for urology patients vs. 50/2267 (2.2%) for all other specialties (P<0.0001). Potential ESBL transmission between organisms occurred in 3 (all on prophylactic antibiotics). Over the study period, there was no significant rise of the monthly incidence between 2014 and 2015 (ANOVA P=0.1). CONCLUSION: This study is the first to document the incidence of ESBL in children (5%), and estimate the frequency of possible plasmid transmission between bacterial species in children. This quantifies the risk of ESBL, especially to urology patients, and mandates better antibiotic stewardship. LEVEL OF EVIDENCE: Level IIc.

[Detection of unusual uropathogens during a period of three years in a regional hospital]. / Detección de uropatógenos inusuales durante un periodo de 3 años en un hospital regional.

Urinary tract infections (UTIs) are one of the most frequent both in the community and in hospitals infectious diseases. The etiology of urinary tract infections is well established but may vary depending on various factors such as age, the presence of underlying diseases such as diabetes, instrumental procedures such as urinary catheterization or exposure to antibiotics or previous hospitalizations. UTIs diagnosed cases were retrospectively reviewed for unusual microorganisms over a period of 3 years (2011-2013) in the Microbiology Laboratory of the Hospital Virgen de las Nieves of Granada (Spain), following the standard operating procedure, which we describe four cases caused by Trichosporon asahii, Aerococcus urinae, Pasteurella bettyae and Neisseria sicca. Hence the importance of having in the Clinical Microbiology Laboratory of the tools necessary to detection UTIs and reach a correct identification in all cases.

Antimicrobial susceptibility pattern of bacteria isolated from patients with urinary tract infection.

OBJECTIVE: To determine the antimicrobial susceptibility pattern of bacterial pathogens in the patients of urinary tract infection reporting at a tertiary care hospital. STUDY DESIGN: Laboratory based study. PLACE AND DURATION OF STUDY: Department of Microbiology, Armed Forces Institute of Pathology, Rawalpindi, from January to December 2012. METHODOLOGY: A total of 440 culture positive bacterial isolates from 1110 urine samples; submitted over a period of one year were included in this study. Identification of bacterial isolates was done by standard biochemical profile of the organisms. The antimicrobial susceptibility of culture positive bacterial isolates was performed by disk diffusion method as recommended by Clinical Laboratory Standard Institute guidelines (CLSI). RESULTS: Out of the 440 culture positive urine samples, 152 (34.6%) were from indoor patients whereas 288 (65.4%) from outdoor patients. Gram negative bacteria accounted for 414 (94%) of the total isolates while rest of the 26 (6%) were Gram positive bacteria. The most prevalent bacterial isolate was Escherichia (E.) coli 270 (61.3%) followed by Pseudomonas (P.) aeruginosa 52 (12%) and Klebsiella (K.) pneumoniae 42 (9.5%). The susceptibility pattern of E. coli showed that 96.2% of the bacterial isolates were sensitive to imipenem, 85.1% to amikacin, 80.7% to piperacillin/tazobactam and 72.6% to nitrofurantoin. In case of P. aeruginsosa, 73% bacterial isolates were sensitive to tazobactam/piperacillin, 69.2% to sulbactam/cefoperazone and 65.38% to imipenem. The antibiogram of K. pneumoniae has revealed that 76.1% of the bacterial isolates were sensitive to imipenem and 52.3% to piperacillin/tazobactam. Nitrofurantoin and imipenem were the most effective antimicrobials amongst the Enterococcus spp. as 92.3% showed susceptibility to this bacterial isolate. CONCLUSION: Majority of the bacterial isolates were sensitive to imipenem and piperacillin/tazobactam while susceptibility to most of the commonly used oral antibiotics was very low. Among the oral antimicrobials, nitrofurantoin showed good susceptibility against Enterobacteriaceae family and Gram positive organisms.

Procedure for microbial identification based on Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry from screening-positive urine samples.

Matrix-Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry is a widely used proteomic technique in clinical microbiology laboratories, and enables microbial identification directly from clinical samples. This study seeks to establish a protocol for bacterial identification from monomicrobial urine samples that have tested positive in the screening with Sysmex UF-1000i (Sysmex Corporation, Kobe, Japan). Sysmex UF-1000i counts ≥1 × 10(7) bacteria/mL indicate a sufficient bacterial concentration to allow direct identification from urine, with 87.5% sensitivity. Microbial identification from urine with Sysmex UF-1000i counts between 1 × 10(5) and 1 × 10(7) bacteria/ml requires preincubation to obtain the adequate amount of bacteria needed for analysis, and 91.7% sensitivity thus being achieved.

Broad identification of bacterial type in urinary tract infection using (1)h NMR spectroscopy.

To address the shortcomings of urine culture for the rapid identification of urinary tract infection (UTI), we applied (1)H-nuclear magnetic resonance (NMR) spectroscopy as a surrogate method for fast screening of microorganisms. Study includes 682 urine samples from suspected UTI patients, 50 healthy volunteers, and commercially available standard strains of gram negative bacilli (GNB) (Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Enterobacter, Acinetobacter, Proteus mirabilis, Citrobacter frundii) and gram positive cocci (GPC) (Enterococcus faecalis, Streptococcus group B, Staphylococcus saprophyticus). Acetate, lactate, ethanol, succinate, creatinine, trimethylamine (TMA), citrate, trimethylamin-N-oxide, glycine, urea, and hippurate were measured by (1)H NMR spectroscopy. All urine specimens were evaluated with culture method. Multivariate discriminant function analysis (DFA) reveals that acetate, lactate, succinate, and formate were able to differentiate, with high accuracy (99.5%), healthy controls from UTI patients. This statistical analysis was also able to classify GNB to GPC infected urine samples with high accuracy (96%). This technique appears to be a promising, rapid, and noninvasive approach to probing GNB and GPC infected urine specimens with its distinguishing metabolic profile. The determination of infection will be very important for rapidly and efficiently measuring the efficacy of a tailored treatment, leading to prompt and appropriate care of UTI patients.

Individualized antibiotic prophylaxis reduces surgical site infections by gram-negative bacteria in instrumented spinal surgery.

PURPOSE: Surgical site infection (SSI) can be a challenging complication after posterior spinal fusion and instrumentation (PSFI). An increasing rate of SSI by gram-negative bacteria (GNB) has been observed. Current guideline recommendations have not been effective for preventing infection by these microorganisms. METHODS: Retrospective cohort study comparing two consecutive groups of patients undergoing PSFI at a single institution. Cohort A includes 236 patients, operated between January 2006 and March 2007, receiving standard preoperative antibiotic prophylaxis with cefazolin (clindamycin in allergic patients). Cohort B includes 223 patients operated between January and December 2009, receiving individualized antibiotic prophylaxis and treatment based on preoperative urine culture. Cultures were done 3-5 days before surgery in patients meeting one of the following risk criteria for urinary tract colonization: hospitalization longer than 7 days, indwelling catheter, neurogenic bladder, history of urinary incontinence, or history of recurrent urinary tract infection. RESULTS: Twenty-two (9.3%) patients in cohort A developed SSI, 68.2% due to GNB. 38 (17%) patients in cohort B were considered at risk for GNB colonization; preoperative urine culture was positive in 14 (36%). After adjusted antibiotic prophylaxis, 15 (6.27%) patients in cohort B developed SSI, 33.4% due to GNB. A statistically significant reduction in GNB SSI was seen in cohort B (Fisher's exact test, p = 0.039). CONCLUSION: Higher preoperative GNB colonization rates were found in patients with neurogenic bladder or indwelling catheters. Preoperative bacteriological screening, treatment for bacteriuria, and individualized antibiotic prophylaxis were effective for reducing GNB SSI.

Performance and clinical significance of direct antimicrobial susceptibility testing on urine from hospitalized patients.

BACKGROUND: Urinary tract infections (UTIs) are common infections in the community and the hospital. With increasing antimicrobial resistance, specifically in the Gram-negative uropathogens, reliable, rapid antimicrobial susceptibility data would be useful to guide antimicrobial treatment. Direct antimicrobial susceptibility testing (DST) of urine with microscopic evidence of Gram-negative bacterial infection and its clinical significance was investigated in this study. METHODS: DST was performed by Kirby-Bauer disk diffusion method using undiluted urine as a non-standardized inoculum. Urine specimens with Gram-negative bacteria on microscopy were included. DST results from growth of Gram-negative bacteria were compared to routine antimicrobial susceptibility testing by Phoenix automated system (AST). Errors were scored as 'very major error' if susceptible by DST but resistant by AST and as 'major error' if resistant by DST but susceptible by AST. All other discrepancies were defined as 'minor error'. Discrepancies were resolved by determination of minimum inhibitory concentrations (MICs) using Etests. After discrepancy analysis, errors were scored as above using the Etest as the reference method. For analysis, specimens were divided into 3 categories: category A: 1 isolate found by DST as well as by routine culture; category B: 1 isolate detected by DST, but more than 1 isolate found on routine culture; category C: more than 1 isolate found by both DST and routine culture. The clinical significance of DST was determined prospectively by investigating the potential impact of DST on antimicrobial therapy. RESULTS: One hundred and sixteen urine specimens were included. For DST and AST there was agreement in 96% of 1152 comparisons in category A (n = 100), 88% of 41 comparisons in category B (n = 4), and 88% of 110 comparisons in category C (n = 12). The 64 discrepancies included 18 very major errors, 7 major errors, and 39 minor errors. Eight very major errors and 11 minor errors were not investigated because the isolates were not available. After Etest MIC determination for the 45 remaining discrepancies, DST showed 1 very major error, 1 major error, and 8 minor errors in category A, none in category B, and 5 major errors and 4 minor errors in category C. Antimicrobial therapy for UTI was prescribed for 53 patients. For 4 patients (8%) therapy was adjusted based on DST because of antimicrobial resistance and for 12 patients (23%) antimicrobial treatment could have been streamlined. CONCLUSIONS: DST on urine is reliable in monobacterial Gram-negative infections. With increasing antimicrobial resistance, DST can make an important contribution to patient management and reduce the use of broad-spectrum antimicrobials.

Patrones de resistencia antimicrobiana en uropatógenos gramnegativos aislados de pacientes ambulatorios y hospitalizados Cartagena, 2005-2008 / Antimicrobial resistance pattern for gram-negative uropathogens isolated from hospitalised patients and outpatients in Cartagena, 2005-2008

Objetivo Determinar el patrón de resistencia antimicrobiana de bacterias patógenas asociadas a infecciones urinarias en pacientes ambulatorios y hospitalizados. Métodos Se realizó un estudio descriptivo entre febrero de 2005 y noviembre de 2008 en el Laboratorio Clínico de la Universidad de San Buenaventura, Cartagena. La susceptibilidad antimicrobiana fue evaluada con el método de difusión en agar empleado la técnica de Kirby Bauer aplicando procedimientos normalizados. Resultados Del total de muestras de orina analizadas (1 384) durante el período de estudio, 32,9 por ciento (455) fueron urocultivos positivos, la mayoría de éstos (81,4 por ciento) provenían de mujeres. Los agentes bacterianos más frecuentes fueron Escherichia. coli (60,1 por ciento), Klebsiella pneumoniae (6,9 por ciento), Pseudomonas aeruginosa (6,6 por ciento), Proteus mirabilis (5,4 por ciento) y Acinetobacter baumannii (1,4 por ciento). Los aislamientos gramnegativos mostraron una alta resistencia a la ampicilina (84,3100 por ciento), amoxacilina/ácido clavulánico (66,5 80,0 por ciento) y ciprofloxacina (40,057,9 por ciento). Conclusión Las bacterias gramnegativas fueron los principales agentes asociados a infecciones urinarias en esta población siendo E. coli el aislamiento más frecuente. La interpretación de los perfiles de susceptibilidad encontrados permite considerar como prudente la administración empírica de cefalosporinas de tercera generación como tratamiento inicial de las infecciones urinarias en esta población.

Objective Determining the microbial aetiology spectrum and antibiotic resistance pattern of uropathogens causing urinary tract infections in hospitalised patients and outpatients. Methods A descriptive study was carried out between February 2005 and November 2008 at the San Buenaventura University's Clinical Laboratory in Cartagena. Antibiotic sensitivity was determined by the Kirby Bauer method. Results Out of the total specimens (1,384) analysed over the four-year study period, 455 of the urine samples (32.9 percent) were culture positive, most (81.4 percent) having come from females. The bacterium isolated most frequently was Escherichia coli (60.1 percent) followed by Klebsiella pneumoniae (6.9 percent), Pseudomonas aeruginosa (6.6 percent), Proteus mirabilis (5.4 percent) and Acinetobacter baumannii (1.4 percent). The Gram-negative isolates displayed a high level of resistance to ampicillin (range 84.3100 percent), amoxicillin/clavulanic acid (range 66.580 percent) and ciprofloxacin (range 4057.9 percent). Conclusion Gram-negative bacteria were responsible for urinary tract infections in the patients involved in this study. The most commonly isolated bacteria were E. coli. Empirical administration of a third-generation cephalosporin for initial treatment of urinary tract infections in this population appears prudent from the perspective of antimicrobial susceptibility.

Absolute and relative accuracy of rapid urine tests for urinary tract infection in children: a meta-analysis.

Rapid urine tests, such as microscopy, for bacteria and white cells, and dipsticks, for leucocyte esterase and nitrites, are often used in children that are unwell to guide early diagnosis and treatment of urinary tract infection. We aimed to establish whether these tests were sufficiently sensitive to avoid urine culture in children with negative results and to compare the accuracy of dipsticks with microscopy. Medline, Embase, and reference lists were searched. Studies were included if urine culture results were compared with rapid tests in children. Data were analysed to obtain absolute and relative accuracy estimates. Data from 95 studies in 95 703 children were analysed. Summary estimates for sensitivity and specificity for microscopy for Gram-stained bacteria were 91% (95% CI 80-96) and 96% (92-98), for unstained bacteria were 88% (75-94) and 92% (84-96), for urine white cells were 74% (67-80) and 86% (82-90), for leucocyte esterase or nitrite positive dipstick were 88% (82-91) and 79% (69-87), and for nitrite-only positive dipstick were 49% (41-57) and 98% (96-99). Microscopy for bacteria with Gram stain had higher accuracy than other laboratory tests with relative diagnostic odds ratio compared with bacteria without Gram stain of 8.7 (95% CI 1.8-41.1), white cells of 14.5 (4.7-44.4), and nitrite of 22.0 (0.7-746.3). Microscopy for white cells should not be used for the diagnosis of urinary tract infection because its accuracy is no better than that of dipstick, laboratory facilities are needed, and results are delayed. Rapid tests are negative in around 10% of children with a urinary tract infection and cannot replace urine culture. If resources allow, microscopy with Gram stain should be the single rapid test used.

[Characteristics of microbiological diagnosis of chronic bacterial prostatitis].

We made a microbiological study of the urine and prostatic secretion (Meares-Stamey test) of 35 patients with chronic bacterial prostatitis (CBP) aged 35-75 years. We conducted a bacterial assay, determined species, sensitivity to synthetic antibacterial fluoroquinolone drugs. A total of 163 bacterial strains were isolated, of them 13 were staphylococcal. Gram-negative bacteria were identified in the test biomaterial only in 16.6% cases. The analysis of staphylococcal sensitivity showed the highest antistaphylococcal effectiveness of levofloxacin and lomefloxacin. Our study confirms an essential role of staphylococcal bacteria in CBP etiology.

[Antimicrobial resistance pattern for gram-negative uropathogens isolated from hospitalised patients and outpatients in Cartagena, 2005-2008]. / Patrones de resistencia antimicrobiana en uropatógenos gramnegativos aislados de pacientes ambulatorios y hospitalizados Cartagena, 2005-2008.

OBJECTIVE: Determining the microbial aetiology spectrum and antibiotic resistance pattern of uropathogens causing urinary tract infections in hospitalised patients and outpatients. METHODS: A descriptive study was carried out between February 2005 and November 2008 at the San Buenaventura University's Clinical Laboratory in Cartagena. Antibiotic sensitivity was determined by the Kirby Bauer method. RESULTS: Out of the total specimens (1,384) analysed over the four-year study period, 455 of the urine samples (32.9 %) were culture positive, most (81.4 %) having come from females. The bacterium isolated most frequently was Escherichia coli (60.1 %) followed by Klebsiella pneumoniae (6.9 %), Pseudomonas aeruginosa (6.6 %), Proteus mirabilis (5.4 %) and Acinetobacter baumannii (1.4 %). The Gram-negative isolates displayed a high level of resistance to ampicillin (range 84.3100 %), amoxicillin/clavulanic acid (range 66.580 %) and ciprofloxacin (range 4057.9 %). CONCLUSION: Gram-negative bacteria were responsible for urinary tract infections in the patients involved in this study. The most commonly isolated bacteria were E. coli. Empirical administration of a third-generation cephalosporin for initial treatment of urinary tract infections in this population appears prudent from the perspective of antimicrobial susceptibility.

Epidemiology of antimicrobial resistance among gram-negative organisms recovered from patients in a multistate network of long-term care facilities.

We identified 1,805 gram-negative organisms in cultures of urine samples obtained over a 10-month period from residents of 63 long-term care facilities. The prevalence of fluoroquinolone resistance in Escherichia coli was 51% (446 of 874 isolates), whereas the prevalences of ceftazidime and imipenem resistance in Klebsiella species were 26% and 6% (84 and 19 of 323 isolates), respectively. The prevalence of resistance varied significantly by facility type, size, and geographic location.