983 resultados para Biology, Molecular|Health Sciences, Pharmacology|Health Sciences, Oncology
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Background. Clostridium difficile is the leading cause of hospital associated infectious diarrhea and colitis. About 3 million cases of Clostridium difficile diarrhea occur each year with an annual cost of $1 billion. ^ About 20% of patients acquire C. difficile during hospitalization. Infection with Clostridium difficile can result in serious complications, posing a threat to the patient's life. ^ Purpose. The aim of this research was to demonstrate the uniqueness in the characteristics of C. difficile positive nosocomial diarrhea cases compared with C. difficile negative nosocomial diarrhea controls admitted to a local hospital. ^ Methods. One hundred and ninety patients with a positive test and one hundred and ninety with a negative test for Clostridium difficile nosocomial diarrhea, selected from patients tested between January 1, 2002 and December 31, 2003, comprised the study population. Demographic and clinical data were collected from medical records. Logistic regression analyses were conducted to determine the associated odds between selected variables and the outcome of Clostridium difficile nosocomial diarrhea. ^ Results. For the antibiotic classes, cephalosporins (OR, 1.87; CI 95, 1.23 to 2.85), penicillins (OR, 1.57; CI 95, 1.04 to 2.37), fluoroquinolones (OR, 1.65; CI 95, 1.09 to 2.48) and antifungals (OR, 2.17; CI 95, 1.20 to 3.94), were significantly associated with Clostridium difficile nosocomial diarrhea Ceftazidime (OR, 1.95; CI 95, 1.25 to 3.03, p=0.003), gatifloxacin (OR, 1.97; CI 95, 1.31 to 2.97, p=0.001), clindamycin (OR, 3.13; CI 95, 1.99 to 4.93, p<0.001) and vancomycin (OR, 1.77; CI 95, 1.18 to 2.66, p=0.006, were also significantly associated with the disease. Vancomycin was not statistically significant when analyzed in a multivariable model. Other significantly associated drugs were, antacids, laxatives, narcotics and ranitidine. Prolong use of antibiotics and an increased number of comorbid conditions were also associated with C. difficile nosocomial diarrhea. ^ Conclusion. The etiology for C. difficile diarrhea is multifactorial. Exposure to antibiotics and other drugs, prolonged antibiotic usage, the presence and severity of comorbid conditions and prolonged hospital stay were shown to contribute to the development of the disease. It is imperative that any attempt to prevent the disease, or contain its spread, be done on several fronts. ^
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Drinking water-related exposures within populations living in the United States-Mexico border region, particularly among Hispanics, is an area that is largely unknown. Specifically, perceptions that may affect water source selection is an issue that has not been fully addressed. This study evaluates drinking water quality perceptions in a mostly Hispanic community living along the United States-Mexico border, a community also facing water scarcity issues. Using a survey that was administered during two seasons (winter and summer), data were collected from a total of 608 participants, of which 303 were living in the United States and 305 in Mexico. A (random) convenience sampling technique was used to select households and those interviewed were over 18 years of age. Statistically significant differences were observed involving country of residence (p=0.002). Specifically, those living in Mexico reported a higher use of bottled water than those living in the United States. Perception factors, especially taste, were cited as main reasons for not selecting unfiltered tap water as a primary drinking water source. Understanding what influences drinking water source preference can aid in the development of risk communication strategies regarding water quality. ^
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Purpose. Recent reports reveals that studies of decision aids reported concern about the balance and accuracy of information included in decision aids. This study explores measures of balance in patient decision aids through a review of prostate cancer screening decision aid studies and analysis of patients’ rating of a patient decision aid for prostate cancer screening. ^ Methods. A data-abstraction form was used to collect the key characteristics, pertaining to balance, of studies included in the review. The key characteristics included (1) sample characteristics (age, race, family history of prostate cancer, and education), (2) description of the decision aid and how it was implemented, and (3) if a measure of balance was used for process evaluation and the rating. A summary table was used to report the findings. Deidentified data was received from a decision aid control trial and logistic regression analysis was used to test the association between the dependent variable (balance) and the independent variables (age, family history, race, screening preference at baseline, education, health insurance status). ^ Conclusion. Three sociodemographic variables remained significant in the final regression model: African American race, education and PSA history. Further research is needed to determine if these variables can predict a man’s perception of balance in prostate cancer screening decision aids. If a patient’s perceptions of balance can be predicted based on specific characteristics, patient report may not be the most objective method of evaluating the acceptability of a decision.^
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Purpose. To examine the association between living in proximity to Toxics Release Inventory (TRI) facilities and the incidence of childhood cancer in the State of Texas. ^ Design. This is a secondary data analysis utilizing the publicly available Toxics release inventory (TRI), maintained by the U.S. Environmental protection agency that lists the facilities that release any of the 650 TRI chemicals. Total childhood cancer cases and childhood cancer rate (age 0-14 years) by county, for the years 1995-2003 were used from the Texas cancer registry, available at the Texas department of State Health Services website. Setting: This study was limited to the children population of the State of Texas. ^ Method. Analysis was done using Stata version 9 and SPSS version 15.0. Satscan was used for geographical spatial clustering of childhood cancer cases based on county centroids using the Poisson clustering algorithm which adjusts for population density. Pictorial maps were created using MapInfo professional version 8.0. ^ Results. One hundred and twenty five counties had no TRI facilities in their region, while 129 facilities had at least one TRI facility. An increasing trend for number of facilities and total disposal was observed except for the highest category based on cancer rate quartiles. Linear regression analysis using log transformation for number of facilities and total disposal in predicting cancer rates was computed, however both these variables were not found to be significant predictors. Seven significant geographical spatial clusters of counties for high childhood cancer rates (p<0.05) were indicated. Binomial logistic regression by categorizing the cancer rate in to two groups (<=150 and >150) indicated an odds ratio of 1.58 (CI 1.127, 2.222) for the natural log of number of facilities. ^ Conclusion. We have used a unique methodology by combining GIS and spatial clustering techniques with existing statistical approaches in examining the association between living in proximity to TRI facilities and the incidence of childhood cancer in the State of Texas. Although a concrete association was not indicated, further studies are required examining specific TRI chemicals. Use of this information can enable the researchers and public to identify potential concerns, gain a better understanding of potential risks, and work with industry and government to reduce toxic chemical use, disposal or other releases and the risks associated with them. TRI data, in conjunction with other information, can be used as a starting point in evaluating exposures and risks. ^
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Gasoline is perhaps one of the most familiar substances to people in our society. Benzene is a component of gasoline and it is hemotoxic and carcinogenic at high concentrations. With increased governmental regulation of gasoline and benzene exposure, the hazardous effects of benzene on public health are very limited. As long as environmental conditions meet OSHA regulation standards, most individuals are not aware of the hazardous effect of benzene. However, recent studies have found that less than 1ppm benzene exposure which is below OSHA exposure regulatory standard may cause hematological damage. This paper reviews the relationship among gasoline-related work, daily life gasoline exposure, public health and new updated research in this field. We searched for relevant publications from 1966 through 2006 in three databases: Ovid Medline, PubMed and TOXNET. This review is a means toward educating people about exposure to benzene in different environments. Although government has developed good monitoring and prevention methods to decrease the harm from gasoline, we are aware that the problem is still there. The primary public health message is the benzene may cause hematological effects even at or below the U.S occupational standard of 1ppm.^
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Several studies have examined the association between high glycemic index (GI) and glycemic load (GL) diets and the risk for coronary heart disease (CHD). However, most of these studies were conducted primarily on white populations. The primary aim of this study was to examine whether high GI and GL diets are associated with increased risk for developing CHD in whites and African Americans, non-diabetics and diabetics, and within stratifications of body mass index (BMI) and hypertension (HTN). Baseline and 17-year follow-up data from ARIC (Atherosclerosis Risk in Communities) study was used. The study population (13,051) consisted of 74% whites, 26% African Americans, 89% non-diabetics, 11% diabetics, 43% male, 57% female aged 44 to 66 years at baseline. Data from the ARIC food frequency questionnaire at baseline were analyzed to provide GI and GL indices for each subject. Increases of 25 and 30 units for GI and GL respectively were used to describe relationships on incident CHD risk. Adjusted hazard ratios for propensity score with 95% confidence intervals (CI) were used to assess associations. During 17 years of follow-up (1987 to 2004), 1,683 cases of CHD was recorded. Glycemic index was associated with 2.12 fold (95% CI: 1.05, 4.30) increased incident CHD risk for all African Americans and GL was associated with 1.14 fold (95% CI: 1.04, 1.25) increased CHD risk for all whites. In addition, GL was also an important CHD risk factor for white non-diabetics (HR=1.59; 95% CI: 1.33, 1.90). Furthermore, within stratum of BMI 23.0 to 29.9 in non-diabetics, GI was associated with an increased hazard ratio of 11.99 (95% CI: 2.31, 62.18) for CHD in African Americans, and GL was associated with 1.23 fold (1.08, 1.39) increased CHD risk in whites. Body mass index modified the effect of GI and GL on CHD risk in all whites and white non-diabetics. For HTN, both systolic blood pressure and diastolic blood pressure modified the effect on GI and GL on CHD risk in all whites and African Americans, white and African American non-diabetics, and white diabetics. Further studies should examine other factors that could influence the effects of GI and GL on CHD risk, including dietary factors, physical activity, and diet-gene interactions. ^
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A number of indoor environmental factors, including bioaerosol or aeroallergen concentrations have been identified as exacerbators for asthma and allergenic conditions of the respiratory system. People generally spend 90% to 95% of their time indoors. Therefore, understanding the environmental factors that affect the presence of aeroallergens indoors as well as outdoors is important in determining their health impact, and in identifying potential intervention methods. This study aimed to assess the relationship between indoor airborne fungal spore concentrations and indoor surface mold levels, indoor versus outdoor airborne fungal spore concentrations and the effect of previous as well as current water intrusion. Also, the association between airborne concentration of indoor fungal spores and surface mold levels and the age of the housing structure were examined. Further, the correlation between indoor concentrations of certain species was determined as well. ^ Air and surface fungal measurements and related information were obtained from a Houston-area data set compiled from visits to homes filing insurance claims. During the sampling visit these complaint homes exhibited either visible mold or a combination of visible mold and water intrusion problems. These data were examined to assess the relationships between the independent and dependent variables using simple linear regression analysis, and independent t-tests. To examine the correlation between indoor concentrations of certain species, Spearman correlation coefficients were used. ^ There were 126 houses sampled, with spring, n=43 (34.1%), and winter, n=42 (33.3%), representing the seasons with the most samples. The summer sample illustrated the highest geometric mean concentration of fungal spores, GM=5,816.5 relative to winter, fall and spring (GM=1,743.4, GM=3,683.5 and GM=2,507.4, respectively). In all seasons, greater concentrations of fungal spores were observed during the cloudy weather conditions. ^ The results indicated no statistically significant association between outdoor total airborne fungal spore concentration and total living room airborne fungal spore concentration (β = 0.095, p = 0.491). Second, living room surface mold levels were not associated with living room airborne fungal spore concentration, (β= 0.011, p = 0.669). Third, houses with and without previous water intrusion did not differ significantly with respect to either living room (t(111) = 0.710, p = 0.528) or bedroom (t(111) =1.673, p = 0.162) airborne fungal spore concentrations. Likewise houses with and without current water intrusion did not differ significantly with respect to living room (t(109)=0.716, p = 0.476) or bedroom (t(109) = 1.035, p = 0.304) airborne fungal spore concentration. Fourth, houses with and without current water intrusion did not differ significantly with respect to living room (χ 2 (5) = 5.61, p = 0.346), or bedroom (χ 2 (5) = 1.80, p = 0.875) surface mold levels. Fifth, the age of the house structure did not predict living room (β = 0.023, p = 0.102) and bedroom (β = 0.023, p = 0.065) surface mold levels nor living room (β = 0.002, p = 0.131) and bedroom (β = 0.001, p = 0.650) fungal spore airborne concentration. Sixth, in houses with visually observed mold growth there was statistically significant differences between the mean living room concentrations and mean outdoor concentrations for Cladosporium (t (107) = 11.73, p < 0.0001), Stachybotrys (t (106)=2.288, p = 0.024, and Nigrosporia (t (102) = 2.267, p = 0.025). Finally, there was a significant correlation between several living room fungal species pairs, namely, Cladosporium and Stachybotrys (r = 0.373, p <0.01, n=65), Curvularia and Aspergillus/Penicillium (r = 0.205, p < 0.05, n= 111)), Curvularia and Stachybotrys (r = 0.205, p < 0.05, n=111), Nigrospora and Chaetomium (r = 0.254, p < 0.01, n=105) and Stachybotrys and Nigrospora (r = 0.269, p < 0.01, n=105). ^ This study has demonstrated several positive findings, i.e., significant pairwise correlations of concentrations of several fungal species in living room air, and significant differences between indoor and outdoor concentrations of three fungal species in homes with visible mold. No association was observed between indoor and outdoor fungal spore concentrations. Neither living room nor bedroom airborne spore concentrations and surface mold levels were related to the age of the house or to water intrusion, either previous or current. Therefore, these findings suggest the need for evaluating additional parameters, as well as combinations of factors such as humidity, temperature, age of structure, ventilation, and room size to better understand the determinants of airborne fungal spore concentrations and surface mold levels in homes. ^
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This study aimed to develop and validate The Cancer Family Impact Scale (CFIS), an instrument for use in studies investigating relationships among family factors and colorectal cancer (CRC) screening when family history is a risk factor. We used existing data to develop the measure from 1,285 participants (637 families) across the United States who were in the Johns Hopkins Colon Cancer Genetic Testing study. Participants were 94% white with an average age of 50.1 years, and 60% were women. None had a personal CRC history, and eighty percent had 1 FDR with CRC and 20% had more than one FDR with CRC. The study had three aims: (1) to identify the latent factors underlying the CFIS via exploratory factor analysis (EFA); (2) to confirm the findings of the EFA via confirmatory factor analysis (CFA); and (3) to assess the reliability of the scale via Cronbach's alpha. Exploratory analyses were performed on a split half of the sample, and the final model was confirmed on the other half. The EFA suggested the CFIS was an 18-item measure with 5 latent constructs: (1) NEGATIVE: negative effects of cancer on the family; (2) POSITIVE: positive effects of cancer on the family; (3) COMMUNICATE: how families communicate about cancer; (4) FLOW: how information about cancer is conveyed in families; and (5) NORM: how individuals react to family norms about cancer. CFA on the holdout sample showed the CFIS to have a reasonably good fit (Chi-square = 389.977, df = 122, RMSEA= 0.058 (.052-.065), CFI=.902, TLI=.877, GF1=.939). The overall reliability of the scale was α=0.65. The reliability of the subscales was: (1) NEGATIVE α = 0.682; (2) POSITIVE α = 0.686; (3) COMMUNICATE α = 0.723; (4) FLOW α = 0.467; and (5) NORM α = 0.732. ^ We concluded the CFIS to be a good measure with most fit levels over 0.90. The CFIS could be used to compare theoretically driven hypotheses about the pathways through which family factors could influence health behavior among unaffected individuals at risk due to family history, and also aid in the development and evaluation of cancer prevention interventions including a family component. ^
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Type II diabetes mellitus is a growing problem worldwide and although its association with increased cardiovascular morbidity and mortality is well known, its role in the development of cancer is now being further elucidated. Recently, there has been increasing evidence that not only are diabetics more susceptible towards development of particular types of cancer, but also have worse oncologic outcomes. This retrospective chart review investigates whether diabetics with colon cancer have a poorer prognosis than their nondiabetic counterparts. Patients with high risk Stage II and Stage III colon cancer who were diagnosed and/or treated at The University of Texas M.D. Anderson Cancer Center from 1/1/2000 till 12/1/2004 were included in our study. We carried out a survival analysis using Kaplan-Meier method and multivariable analysis to assess differences in outcomes of the two population groups. We found that the decreased overall survival in diabetics did not reach statistical significance but this could be due to a lower event rate in our study. Larger studies are required to investigate this further. ^
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Monte Carlo simulation has been conducted to investigate parameter estimation and hypothesis testing in some well known adaptive randomization procedures. The four urn models studied are Randomized Play-the-Winner (RPW), Randomized Pôlya Urn (RPU), Birth and Death Urn with Immigration (BDUI), and Drop-the-Loses Urn (DL). Two sequential estimation methods, the sequential maximum likelihood estimation (SMLE) and the doubly adaptive biased coin design (DABC), are simulated at three optimal allocation targets that minimize the expected number of failures under the assumption of constant variance of simple difference (RSIHR), relative risk (ORR), and odds ratio (OOR) respectively. Log likelihood ratio test and three Wald-type tests (simple difference, log of relative risk, log of odds ratio) are compared in different adaptive procedures. ^ Simulation results indicates that although RPW is slightly better in assigning more patients to the superior treatment, the DL method is considerably less variable and the test statistics have better normality. When compared with SMLE, DABC has slightly higher overall response rate with lower variance, but has larger bias and variance in parameter estimation. Additionally, the test statistics in SMLE have better normality and lower type I error rate, and the power of hypothesis testing is more comparable with the equal randomization. Usually, RSIHR has the highest power among the 3 optimal allocation ratios. However, the ORR allocation has better power and lower type I error rate when the log of relative risk is the test statistics. The number of expected failures in ORR is smaller than RSIHR. It is also shown that the simple difference of response rates has the worst normality among all 4 test statistics. The power of hypothesis test is always inflated when simple difference is used. On the other hand, the normality of the log likelihood ratio test statistics is robust against the change of adaptive randomization procedures. ^
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Background. Large field studies in travelers' diarrhea (TD) in multiple destinations are limited by the need to perform stool cultures on site in a timely manner. A method for the collection, transport and storage of fecal specimens that does not require immediate processing, refrigeration and is stable for months would be advantageous. ^ Objectives. Determine if enteric pathogen bacterial DNA can be identified in cards routinely used for evaluation of fecal occult blood. ^ Methods. U.S. students traveling to Mexico in 2005-07 were followed for occurrence of diarrheal illness. When ill, students provided a stool specimen for culture and occult blood by the standard method. Cards were then stored at room temperature prior to DNA extraction. A multiplex fecal PCR was performed to identify enterotoxigenic Escherichia coli and enteroaggregative E. coli (EAEC) in DNA extracted from stools and occult blood cards. ^ Results. Significantly more EAEC cases were identified by PCR done in DNA extracted from cards (49%) or from frozen feces (40%) than by culture followed by HEp-2 adherence assays (13%). Similarly more ETEC cases were detected in card DNA (38%) than fecal DNA (30%) or culture followed by hybridization (10%). Sensitivity and specificity of the card test was 75% and 62%, respectively, and 50% and 63%, respectively, when compared to EAEC and ETEC culture, respectively, and 53% and 51%, respectively compared to EAEC multiplex fecal PCR and 56% and 70%, respectively, compared to ETEC multiplex fecal PCR. ^ Conclusions. DNA extracted from fecal cards used for detection of occult blood is of use in detecting enteric pathogens. ^
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Background. The objective of this retrospective cohort study is to examine the presentation and outcomes for a contemporary series of cancer patients with anorectal infection. In addition, we seek to identify factors which are associated with surgical intervention. ^ Methods. The study cohort was identified from ICD-9 codes for diagnosis of infection of the anal and rectal region and patients who underwent a surgical oncology consultation between 1/2000 and 12/2006. Clinical presentation, treatment rendered, and outcomes were retrospectively recorded. ^ Results. Of the 100 patients evaluated by the surgical oncology service for anorectal infection, 42 were treated non-operatively and 58 underwent surgical intervention. Factors associated with surgical intervention based on logistic multivariable analysis included the diagnosis of an abscess (odds ratio [OR] 10.5; 95% confidence interval [CI] 2.9-38.5) and the documentation of erythema on physical examination (OR 3.1; 95% CI 1.1-8.4). Thrombocytopenia (platelets < 50,000) was associated with non-operative management (OR 0.3; 95% CI 0.1-0.7). Incision and drainage was the most common surgical procedure (79%) while a wide debridement for a necrotizing soft tissue infection was required in 2 patients. Infection-specific 90-day mortality was only 1% (N=1). However, the median overall survival for the entire cohort was only 14.4 months (95% CI 7.9-19.5). ^ Conclusions. Non-operative management is a reasonable treatment option for anorectal infection in patients with cancer. Identification of an abscess, erythema on physical exam, and thrombocytopenia were associated with management strategy. Although rare, necrotizing soft tissue infections are associated with significant mortality. ^
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Hepatocellular carcinoma (HCC) has been ranked as the top cause of death due to neoplasm malignancy in Taiwan for years. The high incidence of HCC in Taiwan is primarily attributed to high prevalence of hepatitis viral infection. Screening the subjects with liver cirrhosis for HCC was widely recommended by many previous studies. The latest practice guideline for management of HCC released by the American Association for the Study of Liver Disease (AASLD) in 2005 recommended that the high risk groups, including cirrhotic patients, chronic HBV/HCV carriers, and subjects with family history of HCC and etc., should undergo surveillance.^ This study aims to investigate (1) whether the HCC screening program can prolong survival period of the high risk group, (2) what is the incremental cost-effectiveness ratio of the HCC screening program in Taiwan, as compared with a non-screening strategy from the payer perspective, (3) which high risk group has the lowest ICER for the HCC screening program from the insurer's perspective, in comparison with no screening strategy of each group, and (4) the estimated total cost of providing the HCC screening program to all high risk groups.^ The high risk subjects in the study were identified from the communities with high prevalence of hepatitis viral infection and classified into three groups (cirrhosis group, early cirrhosis group, and no cirrhosis group) at different levels of risk to HCC by status of liver disease at the time of enrollment. The repeated ultrasound screenings at an interval of 3, 6, and 12 months were applied to cirrhosis group, early cirrhosis group, and no cirrhosis group, respectively. The Markov-based decision model was constructed to simulate progression of HCC and to estimate the ICER for each group of subjects.^ The screening group had longer survival in the statistical results and the model outcomes. Owing to the low HCC incidence rate in the community-based screening program, screening services only have limited effect on survival of the screening group. The incremental cost-effectiveness ratio of the HCC screening program was $3834 per year of life saved, in comparison with the non-screening strategy. The estimated total cost of each group from the screening model over 13.5 years approximately consumes 0.13%, 1.06%, and 0.71% of total amount of adjusted National Health Expenditure from Jan 1992 to Jun 2005. ^ The subjects at high risk of developing HCC to undergo repeated ultrasound screenings had longer survival than those without screening, but screening was not the only factor to cause longer survival in the screening group. The incremental cost-effectiveness ratio of the 2-stage community-based HCC screening program in Taiwan was small. The HCC screening program was worthy of investment in Taiwan. In comparison with early cirrhosis group and no cirrhosis group, cirrhosis group has the lowest ICER when the screening period is less than 19 years. The estimated total cost of providing the HCC screening program to all high risk groups consumes approximately 1.90% of total amount of adjusted 13.5-year NHE in Taiwan.^
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Background. Despite the increasing attention to the effects of dietary factors on lung cancer risk, epidemiological research on the role of black/green tea and coffee intake and lung cancer risk is scarce. The purpose of this study was to explore the following three hypotheses: (1) the preventive (protective) effect from lung cancer is higher in green tea than in black tea and coffee consumption. (2) brewed tea (either black or green) daily drinkers have lower odds of lung cancer than non-drinkers of brewed tea (3) regular black and green tea have more preventive effect against lung cancer than decaffeinated teas due to the synergistic effect of caffeine and other tea components. ^ Methods. Data on 1,088 lung cancer cases and 1,127 controls from an ongoing epidemiological study of lung cancer by the Department of Epidemiology of the University of Texas M.D. Anderson Cancer were analyzed. Multiple logistic regressions were performed for testing associations between frequency of specific types of tea/coffee consumption and the risk of lung cancer. ^ Results. We observed that more than a cup a week of green tea and decaffeinated black tea were significantly associated with reduced odds of lung cancer by 64% for green tea (adjusted OR = 0.44; 95% CI = 0.31–0.64), 36% for decaffeinated black tea (OR = 0.64; 95% CI = 0.45–0.90), when compared with non-drinkers and those who drank less than a cup a week. On the other hand, increasing intake of regular coffee (more than 3 cups a day) was associated with a 30% higher odds ratio of lung cancer (OR = 1.30; 95% CI = 1.01–1.09). No association was found between regular black tea, decaffeinated coffee consumption and the odds ratio of lung cancer. However, when drinkers of other tea/coffee beverages were excluded from each model in order to explore the independent effect of each type of tea/coffee, green tea and decaffeinated black tea-lung cancer associations remained but no association was observed for drinkers of regular coffee. ^ Conclusion. We report the chemopreventive effects of more than a cup a week of green tea and decaffeinated black tea on lung cancer. ^
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The cause of infection of about a third of all travelers' diarrhea patients studied is not identified. Stools of these diarrhea patients tested for known enteric pathogens are shown to be negative, and identified as pathogen negative stools. We proposed that the third of these diarrhea patients might not only include at present unknown pathogens, but also known pathogens that go undetected. Conventionally, a probability sample of five E. coli colonies are used detect enterotoxigenic E. coli (ETEC) and other diarrhea-producing E. coli from stool cultures. We compared this conventional method of using five E. coli colonies, to the use of up to twenty E. coli colonies. Testing for up to fifteen E. coli colonies detected about twice as many ETEC when compared to the detection of ETEC, testing for five E. coli colonies. When the number of E. coli colonies tested was increased from 5 to 15, the detection of ETEC increased from 19.0% to 38.8%. The sensitivity of the assay with 5 E. coli colonies was statistically significantly different to the sensitivity of the assay with 10 E. coli colonies, suggesting that for the detection of ETEC at least 10 colonies of E. coli should be tested.^