Thesis (DR. P.H.)--University of Michigan.

Orientadores: Célia Regina Garlipp, Carlos Emilio Levy / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-21T18:20:39Z (GMT). No. of bitstreams: 1 Martinez_MayaraHidalgoMagri_M.pdf: 2010266 bytes, checksum: 23bb4f89ea7b258a0fd5fe0e20f6cc1f (MD5) Previous issue date: 2012 / Resumo: Infecção do trato urinário (ITU) é muito comum na prática clínica, acometendo pessoas de ambos os sexos em todas as faixas etárias. Para seu diagnóstico é importante definir rapidamente a presença de bacteriúria e piúria bem como a etiologia da doença através da urocultura. A urocultura é o teste microbiológico mais comum na prática laboratorial, embora seja um procedimento demorado e de custo relativamente elevado. Nosso objetivo foi avaliar a aplicação de um sistema automatizado de análise da urina (LabUMat/UriSed) como método de triagem para a investigação de ITU através da comparação de seus resultados com os das uroculturas. Analisamos amostras de urina de pacientes adultos e crianças de ambos os sexos provenientes de ambulatórios e enfermarias do Hospital de Clínicas da UNICAMP encaminhados às Seções de Líquidos Biológicos e Microbiologia da Divisão de Patologia Clínica para análise físicoquímica, sedimento e urocultura. Foram estabelecidos valores de cortes baseados na comparação dos resultados das uroculturas com os parâmetros urinários: leucócito-esterase, nitrito, leucócitos, bactérias e leveduras, sendo que a positividade de pelo menos um destes parâmetros classificava a amostra para uma triagem positiva para ITU. O estudo foi conduzido em três etapas: Na primeira etapa, a análise de 2126 amostras de urinas permitiu adotar um primeiro valor de corte para os parâmetros analisados: contagem de bactérias >11/campo; contagem de leucócitos >5/campo, presença de leveduras além de nitrito e leucócito-esterase positivos. Esses valores foram comparados com os resultados da urocultura em meio CLED e testados na rotina laboratorial. Em uma segunda etapa, com a finalidade de aprimorar o valor de corte dos parâmetros e aumentar o valor preditivo positivo sem comprometer o valor preditivo negativo, estabeleceu-se um novo valor de corte. Para tanto, foram analisadas 2075 amostras de urinas e com os seguintes valores de corte estabelecidos: contagem de bactérias 'maior ou igual'12,5/campo; contagem de leucócitos >5/campo, presença de leveduras e nitrito bem como leucócito-esterase positivo 'maior ou igual'2+. Esses valores foram comparados com os resultados das uroculturas em meio CLED e testados na rotina laboratorial. A fim de refinar e validar o teste de triagem para urocultura foram analisados, em uma terceira etapa, 1379 amostras de urina. Nesta etapa os valores de corte dos parâmetros foram: contagem de bactérias >12,5/campo, contagem de leucócitos >5/campo, presença de leveduras e leucócito - esterase positivos 'maior ou igual'2+. Nesta etapa as amostras cujos parâmetros urinários avaliados estavam abaixo do valor de corte, foram consideradas negativas para ITU e semeadas em meio CLED. As amostras em que pelo menos um dos parâmetros estudados estava acima do valor de corte, foram consideradas positivas, sendo semeadas em meio Chromagar a fim de se identificar presuntivamente os patógenos. O teste mostrou sensibilidade de 97%, valor preditivo negativo de 99%, valor preditivo positivo de 27%, especificidade de 59% e acurácia de 64%. Em todas as etapas observou-se uma potencial redução de 50% nas semeaduras de uroculturas. Os dados sugerem que o sistema automatizado LabUMat / UriSed é uma boa ferramenta para a triagem de ITU, especialmente se considerarmos os dados clínicos dos pacientes / Abstract: Urinary tract infection (UTI) is very common in clinical practice, affecting people of both genders in all age groups. For the laboratory diagnosis of UTI is of great importance the definition of significant bacteriuria and pyuria and a bacterial culture of a urine sample to establish the etiology of the disease. The quantitative urine culture is the commonest microbiology test in Clinical Pathology Laboratory practice, although it is a very time-consuming and expensive procedure. Our aim was to evaluate the performance of the LabUMat with UriSed System as a screening method for the investigation of UTI comparing its results with the outcome of urine culture. We studied urine samples from children and adults of both genders from outpatients and hospitalized patients from Clinical Hospital / UNICAMP referred to Body Fluids and Microbiology Laboratories at Division of Clinical Pathology for physicochemical analysis, sediment observation and urine culture. We established cut-off values based on the comparison of the outcome of urine cultures with urinary parameters: leukocyte esterase, nitrite and quantitative determination of bacteriuria, leukocyturia and presence of yeasts. A positivity of at least one parameter classified the sample as a positive screening of UTI. This study was conducted in three stages: In the first stage, the analysis of 2,126 urine samples allowed to adopt the first cut-off value for the parameters analyzed: quantification of bacteriuria (>11 elements/hpf), quantification of leukocyturia (>5 cells/hpf), presence of yeasts besides nitrite and leukocyte esterase positive. These values were compared with the outcome of uroculture in CLED agar medium culture and tested in the laboratory routine. In the second stage, in order to improve cut-off values of urinary parameters and increase the positive predictive value without compromising the negative predictive value, it was established a new cut-off value. We analyzed 2,075 urine samples with the following established cut-off values: quantification of bacteriuria (> or = 12.5 elements/hpf) and leukocyturia (> 5 cells/hpf), presence of yeasts, nitrite and leukocyte esterase positive (> or = 2+). These values were compared with the outcome of uroculture and tested in the laboratory routine. In order to refine and validate the screening test for uroculture were analyzed, in a third stage, 1,379 urine samples. In this stage the cutoff values of the parameters were: quantification of bacteriuria (>12.5 elements/hpf) and leukocyturia (> 5 cells/hpf), presence of yeasts and leukocyte esterase positive (> or = 2+). In this stage the urinary samples whose evaluated parameters were below the cut-off value were considered negative for UTI and were plated in CLED agar medium culture. Samples which at least one of the parameters evaluated was above the cut-off value, were considered positive, and were plated in Chromagar commercial medium, in order to presumptively identify pathogens. The test showed sensitivity of 97%, negative predictive value of 99%, positive predictive value of 27%, specificity of 59% and accuracy of 64%. In all stages we observed a potential 50% reduction in sowing urocultures. The data suggest that the LabUMat with UriSed System is a good tool for screening for UTI, especially if we consider patients' clinical data / Mestrado / Ciencias Biomedicas / Mestra em Ciências Médicas

Class of 2012 Abstract / Specific Aims: 1• Determine the results of urine culture and susceptibility testing for patients with uncomplicated UTI at an emergency department 2• Determine empiric antibacterial agents prescribed for treatment of uncomplicated UTI in the emergency department 3• Compare pathogen susceptibility pattern specific for patients with uncomplicated UTI compared to the overall institution antibiogram Examine the use of cephalexin for uncomplicated UTI in emergency department patients Methods: A retrospective electronic medical records of adult female patients admitted to University Medical Center in Tucson, Arizona, emergency department with a diagnosis of uncomplicated urinary tract infection (UTI) between June 1, 2010 and May 31, 2011 were collected. Different aspects of uncomplicated urinary tract infection (UTI) were characterized, and prescriptions for empiric antibiotic treatment were recorded. Culture results and susceptibility reports as well as antibacterial treatment decisions were studied to evaluate types of pathogens and resistance patterns along with therapy prescribed. The data was managed and analyzed by using SAS. All data was tabulated and described using summary statistics. Main Results: The dominant isolate of the study population was E.coli (88%). Cephalexin was prescribed 76% of the time, nitrofurantoin 8.4%, ciprofloxacin 7.6%, and TMP/SMX 5% of the time. The susceptibility rate of ampicillin was 50%, cefazolin 91%, ciprofloxacin 98%, nitrofurantoin 92%, and TMP/SMX 76%. Conclusions: Our study revealed that the resistant rate of TMP/SMX exceeded 20%; however, ciprofloxacin and nitrofurntoin susceptibility remains high. Cephalexin was the most commonly prescribed treatment, but not included in the antimicrobial susceptibility test (AST) panel.

No description available.

Class of 2015 Abstract / Objectives: In 2011, the American Academy of Pediatrics released an updated urinary tract infection guideline that addressed diagnosis, antibiotic treatment, and duration of therapy in children ages 2-24 months. The objectives of this study were to evaluate the appropriateness of antibiotic prescribing and compare outcomes between age groups. Methods: This retrospective chart review included patients aged 1 month through 12 years admitted to a regional academic medical center from January through July 2014 and diagnosed with UTI or pyelonephritis. Patients were identified using ICD-9 codes. Demographic information, antibiotic treatment, length of stay, and complications were collected and the chi square statistical test was used to compare results between age groups. Results: There were 104 patients included in this study. The most common bacteria cultured were Escherichia coli (85%). Ceftriaxone (71%) and cephalexin (30%) were the most commonly prescribed empiric and discharge antibiotic, respectively. Based on guideline recommendations and culture results, inappropriate antibiotic selection only occurred with 7% of the orders while inappropriate prescribing occurred 35% of the time. Readmission within 90 days occurred in 15% of patients aged 2-24 months (guideline age group) and in 14% of all other patients (P>0.05). Conclusions: There was no difference between age groups with respect to inappropriate antibiotic prescribing or complications for pediatric UTI treatment and inappropriate antibiotic dosing occurred more frequently than inappropriate selection. More research is necessary to assess the impact of the guidelines on prescribing practices and factors associated with inappropriate prescribing.

Class of 2011 Abstract / OBJECTIVES: To evaluate the appropriateness of discharge antimicrobial medications for UTI in an adult population based on therapy prescribed. METHODS: In this retrospective chart review study the appropriateness of discharge antimicrobial therapy for patients admitted to an academic medical center during 3 weeks in 2010 was assessed based on culture results, estimated renal function, reported drug allergies, route of administration, and change in UTI from in-house to discharge prescribed therapy. RESULTS: A total of 35 patients with discharge UTI antimicrobials within the study period met inclusion criteria and were evaluated. According to available urinary culture and susceptibility data, 22 of 35 (62.8%) of received an appropriate antimicrobial therapy. Based on reported gastrointestinal function, all 35 patients could take oral medications but two patients with an appropriate oral therapy option received intravenous therapy. All patients were discharged with antimicrobials that were appropriate according to patients’ reported drug allergies and only one patient received an antimicrobial agent that was inappropriately adjusted based on the patient’s estimated renal function. UTI antimicrobial therapies were the same at 24 hours prior to discharge and as the discharge antimicrobial in 100% of patient cases evaluated CONCLUSION: The antimicrobial UTI discharge therapy was evaluated for appropriateness based on urine culture results, patients’ allergies, and patients’ estimated renal function. Overall, antimicrobial therapy was only appropriate in 22 of 35 (62.8%) of patients based on the available culture results.

Urinary tract infections are generally preceded by transfer of organisms from the distal urethra to the bladder (20, 148). However, although urinary infections are predominantly due to pure cultures of Escherichia coli, the distal urethra contains a mixed flora in which E. coli is relatively uncommon and anaerobes predominate (73, 103). This discrepancy between the bladder and distal urethral flora may be due to differential adhesion or differential growth rates. In this dissertation I have tested the hypothesis that differential growth rates of urethral organisms in urine explains the predominance of E. coli as a pathogen. These experiments showed that the balance between bacterial growth and washout may have a pivotal role in the pathogenesis of infection and perhaps therefore in treatment. A model of the human bladder used for the pathogenesis studies was then used to study the activity of mecillinam and ampicillin under conditions simulating human urinary infection. The model proved realistic especially for synergy studies where shortcomings in conventional in vitro methods are a cause for concern. The following topics were studied. 1. Urine was chosen as a test medium for definitive experiments because growth rates of organisms other than E. coli were different in broth and in urine. A method for sterilizing urine in bulk was developed which did not affect growth supporting properties. 2. E. coli was shown to grow faster and to have a shorter lag period than almost all other organisms when studied in shake culture. 3. A continuous culture model of the human urinary bladder was employed for differential growth studies of organisms in sterilized human urine. This model reproduced many of the characteristics of the human lower urinary tract and enabled study of the balance between bacterial growth and the tendency of urine to wash organisms out of the tract. 4. Mixed cultures of approximately equal numbers of E. coli and a second potential urinary' pathogen were introduced into the bladder model and quantitative cultures performed at intervals up to 24 h. In 15 experiments E. coli eventually dominated the second pathogen which was sometimes undetectable at 24 h. Similar changes in bacterial populations seen in infected patients indicate that differential growth rates may be an important determinant of the pathogenicity of E. coli. 5. The use of the bladder model was then extended to investigations of antibiotic activity under realistic conditions. The value of the model for synergy studies with ampicillin and mecillinam was assessed by parallel conventional in vitro tests and an animal infection protection test*. The bladder model gave similar results to mammalian studies and appeared to be far superior to conventional methods. This model may be valuable in the initial assessment of new urinary antibiotics. 6. A representative array of organisms for the above study was selected following a survey of resistance patterns of 2000 clinical isolates of Enterobacteriaceae. An incidental by-product of this survey was the establishment of a breakpoint for mecillinam susceptibility in the Kirby-Bauer antibiotic disk test. 7. Work on the effect of mecillinam and/or ampicillin upon bacterial viability was extended to investigations of the relative contribution of permeability barriers and 3-lactamases to antibiotic susceptibility. Unlike ampicillin, mecillinam resistance of 77 clinical isolates of bacteria appeared to be independent of intracellular 3-lactamase levels, suggesting that the barrier effect may be more pronounced in bacterial resistance to mecillinam than to ampicillin. Kinetic studies using urine as a growth medium, and in particular the use of a bladder model have provided a unifying explanation of many features of both the pathogenesis and treatment of urinary infections. * Carried out by Dr. R.C. Cleeland. / Science, Faculty of / Microbiology and Immunology, Department of / Graduate

No description available.

Thesis (D.P.H.)--University of Michigan, 1994. / Also issued in print.

Thesis (M.S.)--University of Michigan, 1983.