Stool Polymerase Chain Reaction Research Articles

P852 Introduction of Entamoeba histolytica serology testing in the management of inflammatory bowel disease patients at University Hospitals of Leicester, UK

Abstract Background Amoebic colitis can mimic inflammatory bowel disease (IBD) in clinical presentation, endoscopic and (to some extent) histological findings. Four patients with amoebic colitis were misdiagnosed with IBD or an IBD flare at University Hospitals of Leicester (UHL), UK in 2018. This prompted a change in practise in our department and we began screening for Entamoeba histolytica in patients with newly-diagnosed IBD, a flare or those being considered for biologics. We analysed cases of possible amoebic colitis after this change by reviewing IBD patients with a positive E. histolytica immunofluorescence antibody test (IFAT). Methods We conducted a retrospective electronic and case note review of patients with IBD and positive amoeba IFAT serology >1:80 from April 2019 through September 2019. We collected information including Crohn’s disease (CD), ulcerative colitis (UC), IBD treatment, histological findings, travel history, stool E. histolytica DNA polymerase chain reaction (PCR) and amoebic serology including IFAT and Cellulose Acetate Precipitin test (CAP). The histology of endoscopic biopsies for 16 of the IFAT positive patients was reviewed specifically for amoebic trophozoites. Results During the study period we identified 26 IFAT positive patients, excluded 3 patients that were felt to be non-IBD; 23 were included in the study. The median age was 37.8 (range 16–86); 43.5% were male. Four had a diagnosis of UC; 19 had CD. 12 were new IBD presentations. Seven patients had a relevant travel history (Jamaica, Thailand, Turkey, Italy, Greece, and Spain). Four did not have a travel history. Travel history was unknown for 12. Three patients were on biologics, one on biologics and thiopurines. Five were on thiopurines, three on thiopurines and steroids. Four were on steroids only, four on 5-ASAs. Three were on no treatment. Two out of 16 patients reviewed had amoebic trophozoites on endoscopic biopsy, unfortunately stool PCR was not sent on these two patients. Stool E. histolytica DNA PCR, was sent for 19 patients and was negative in those cases. All 24 patients were negative for CAP. Conclusion While IFAT is helpful in detecting past exposure it is only 75% sensitive for amoebic colitis. Even if IFAT and CAP are combined it is difficult to differentiate amoebic colitis from IBD. It is not clear if these cases represent past infections, early infections that precipitated an IBD flare, early infections that arose in the setting of immunosuppression, or false positive IFATs. The risk of infection in the immunosuppressed patient is high and the consequences of misdiagnosis are significant therefore a comprehensive screening method is merited; this may encompass IFAT ± CAP, stool E. histolytica DNA PCR, and possibly histological review.

Giardiasis mimicking acute abdomen in a renal transplant patient; a clinical and diagnostic challenge

Background: Intestinal infection in the post-transplant period is a common source of morbidity and mortality. Diarrhea with or without abdominal pain, bloating, nausea and vomiting constitute the most common symptomology which guides the clinician towards appropriate treatment, but what happens when the clues are few? Case Presentation: We report a case of recent renal allograft recipient who presented with severe abdominal pain without diarrhea or fever. After undergoing various tests, the diagnosis was finally clinched by jejunal biopsy since, it is supported by stool polymerase chain reaction. Conclusions: This case highlights a common organism like giardia can have a varied presentation. This case mimicking almost as an acute abdomen while can present with a diagnostic challenge.

Gastroenteritis in Men Who Have Sex With Men in Seattle, Washington, 2017-2018.

Men who have sex with men (MSM) are at risk for sexual transmission of enteric pathogens. The microbiology of gastroenteritis in MSM has not been examined since the advent of antiretroviral therapy and molecular diagnostics. Our objective was to assess the causes of gastroenteritis among MSM living with and without human immunodeficiency virus (HIV) coinfection in Seattle, Washington. We conducted a retrospective cohort study of 235 MSM who underwent multiplex stool polymerase chain reaction (PCR) testing between 1 January 2017 and 1 June 2018. We abstracted clinical and laboratory data from electronic medical records. Parallel or reflexive culture and susceptibility testing were performed when PCR detected cultivable pathogens. Among 235 MSM tested (268 episodes), 131 had 151 episodes with positive test results. 148 (63.0%) individuals were living with HIV. Among positive tests, 88.7% detected a bacterial pathogen, 26% a virus, and 40% a parasite. Diarrheagenic Escherichia coli (enteroaggretative, enteropathogenic), Shigella, and Campylobacter were the most commonly detected bacteria (33.1%, 30.5%, and 17.2% of positive samples, respectively). Forty-three percent of positive specimens had ≥2 pathogens. Etiologies and clinical presentations were similar between men living with and without HIV. Cultured Shigella and Campylobacter isolates were frequently resistant to multiple antibiotics. MSM present with gastroenteritis from varied pathogens, including some not detected by conventional stool culture. High levels of antibiotic resistance are consistent with frequent antibiotic exposure in this population and the transmission of multiresistant strains. New approaches are needed to detect, treat, and prevent enteric infections in MSM.

119 Kinetics of Stool Polymerase Chain Reaction in Clostridioides difficile Infection and Its Utility in Predicting Recurrence

INTRODUCTION: Testing strategies for Clostridioides difficile infection (CDI) remain a clinical conundrum with stool polymerase chain reaction (PCR) being highly sensitive; this high sensitivity may mean that PCR would remain positive for several weeks after CDI resolution. We studied the kinetics of PCR testing positivity in CDI, and whether a positive test during or after treatment predicts recurrence. METHODS: Adults with watery diarrhea and positive C. difficile PCR from 10/2009 to 5/2017 were included. Treatment was given per standard of care. Five serial stool samples collected within 60 days after treatment initiation and additionally clinically indicated samples were included. Recurrent CDI was defined as typical CDI symptoms after interim symptom resolution with positive stool PCR within 56 days of treatment. A positive stool test in the absence of symptoms was considered colonization and treatment was not offered. Descriptive statistics and Fisher's test were used, as appropriate. Kaplan-Meier survival curves for time to first negative PCR from treatment initiation, and log-rank test to compare treatments [metronidazole (MET) vs vancomycin (VAN)] were used. P < 0.05 was considered statistically significant. RESULTS: Fifty patients, median age 51 (range 20–86) years, 66% female, were included. Initial treatment was MET in 50% (25), VAN in 44% (22), both MET and VAN in 4% (2) and fidaxomicin in 2% (1). Median treatment duration was 14 (range 8–60) days. Overall, 82% (41) patients submitted ≥3 samples at variable times. Median time to first negative PCR was 9 days (95% CI, 7–14 days) after treatment initiation (Figure 1). This was similar in MET and VAN treated patients (P = 0.5; Figure 2). CDI recurred in 28% (14) of patients. Overall, 13 patients (33%) had ≥1 positive PCR(s) during and 45% (19) had ≥1 positive PCR(s) after treatment. Patients with positive vs negative PCR(s) during treatment trended towards a higher risk of recurrence [OR 3.9 (95% CI, 0.9–16.1), P = 0.054]. Patients with positive PCR(s) after treatment completion also had a non-significant trend towards a higher risk of recurrence [OR 2.8 (95% CI, 0.7–11.5), P = 0.15]. CONCLUSION: Median time to first negative PCR in CDI was 9 days from treatment initiation. Positive PCR during or after treatment did not predict recurrence, though the positive odds ratio indicates the need for a larger study. Patients with CDI should not routinely undergo repeat testing to predict recurrence.

A Case of Intestinal Microsporidiosis in a Renal Transplant Recipient

Post-renal transplant diarrhea is a common clinical presentation. An extensive list of potential etiology adds to the diagnostic dilemma. In cases of prolonged or intractable diarrhea, invasive tests are often performed. Intestinal microsporidia can be diagnosed with simple non-invasive stool polymerase chain reaction (PCR). Based on this case, we propose an easy to follow flow chart and present a literature review on post-renal transplant diarrhea. Further multicenter validation testing is required for the proposed flow chart. J Med Cases. 2019;10(8):229-233 doi: https://doi.org/10.14740/jmc3340

41-Year-Old Man With Fever and Bloody Diarrhea

41-Year-Old Man With Fever and Bloody Diarrhea

Experiences from multiplex PCR diagnostics of faeces in hospitalised patients: clinical significance of Enteropathogenic Escherichia coli (EPEC) and culture negative campylobacter

BackgroundIn hospitalised patients with diarrhoea a positive campylobacter stool Polymerase Chain Reaction (PCR) test with negative culture results as well as Enteropathogenic Escherichia coli (EPEC) positive stool PCRs, challenges the clinician and may lead the unexperienced clinician astray. The aim of the study was to elucidate the clinical significance of positive Campylobacter and/or EPEC test results in hospitalised patients with diarrhoea.MethodsWe conducted a retrospective case-case study. Case groups with 1) EPEC only and 2) EPEC in combination with any other pathogen in the PCR multiplex array, 3) PCR positive/culture negative Campylobacter, and 4) PCR positive/culture positive Campylobacter were compared. Medical records were reviewed and cases classified according to pre-specified clinical criteria as infectious gastroenteritis or non-infectious causes for diarrhoea. We analyzed the association between laboratory findings (the 4 subgroups) and the pre-specified clinical classification. We further sequenced culture negative campylobacter samples and tested EPEC for bundle forming pilus A (bfpA) gene, distinguishing typical from atypical EPEC.ResultsA total of 291 patients were included, 169 were PCR positive for Campylobacter and 122 for EPEC. For both pathogens, co-infections were more common in culture negative/PCR positive samples than in culture positive samples. Clinical characteristics differed significantly in and between groups. Campylobacter culture positive patients had very high prevalence of characteristics of acute infectious gastroenteritis, whereas patients with PCR positive test results only often had an alternative explanation for their diarrhoea. Culture positives were almost exclusively C. jejuni/coli, whereas in culture negatives, constituting a third of the total PCR positives, C. concisus was the most frequent species. The vast majority of EPEC only positives had documented non-infectious factors that could explain diarrhoea. The EPEC co-infected group mimicked the culture positive campylobacter group, with most patients fulfilling the infectious gastroenteritis criteria.ConclusionsIn hospitalised patients, positive PCR results for campylobacter and EPEC should be interpreted in a clinical context after evaluation of non-infectious diarrhoea associated conditions, and cannot be used as a stand-alone diagnostic tool.

A Comparison of Stool Enteropathogen Detection by Semiquantitative PCR in Adults With Acute Travelers' Diarrhea Before and 3 Weeks After Successful Antibiotic Treatment.

We evaluated stool enteropathogen detection by semiquantitative polymerase chain reaction (PCR) in 108 subjects with travelers’ diarrhea before and 3 weeks after treatment. Stool samples from 21 subjects were positive for the same pathogen species at both visits. We discuss factors that should be considered when interpreting stool PCR data after treatment.

Streptococcus pyogenes bacteremia and toxic shock syndrome related to Strongyloides stercoralis hyperinfection: a case report

BackgroundWe describe a patient with Strongyloides stercoralis hyperinfection associated with Streptococcus pyogenes and with streptococcal toxic shock syndrome. To the best of our knowledge this association has not been previously described.Case presentationA 78 year-old Israeli man, who was born in Iraq but lived in Israel for 66 years, presented with multi-organ failure including acute kidney and hepatic injury, coagulopathy, and lactic acidosis. He had a medical history including aortic valve replacement, diabetes mellitus, spinal stenosis, and low back pain treated with repeated local steroid injections. Blood cultures were positive for Streptococcus pyogenes and antibiotic treatment was switched to penicillin G, clindamycin, and intravenous immunoglobulins. Repeated physical examinations failed to identify the source of the bacteremia. On day 12 of hospitalization the serology results for Strongyloides stercoralis sent on admission, because of chronic eosinophilia, came back positive. A microscopic stool examination and stool polymerase chain reaction were positive for Strongyloides stercoralis. Ivermectin therapy was commenced and continued for a total of 4 weeks. He was discharged for rehabilitation after 25 days.He had no exposure to endemic countries or to immigrants. During many years he had multiple gastrointestinal symptoms, respiratory symptoms, cutaneous symptoms, chronic eosinophilia, and high immunoglobulin E levels. He underwent several operative procedures and numerous hospitalizations and medical encounters with different experts but a parasitic infection was not considered. His asymptomatic daughter was also found to be serologically positive.ConclusionsStrongyloides stercoralis hyperinfection associated with Streptococcus pyogenes bacteremia and toxic shock is described for the first time. The case also highlights the importance of history taking and reviewing past laboratory results, the utility of serological tests for Strongyloides stercoralis, and the importance of screening asymptomatic family members of an infected patient. Strongyloides stercoralis hyperinfection must be considered in the differential diagnosis of any patient with Streptococcus pyogenes bacteremia or toxic shock of no clear source as well as in symptomatic patients with chronic or intermittent eosinophilia, even without any epidemiological risk factors.

Enteric Infection in Relapse of Inflammatory Bowel Disease: The Utility of Stool Microbial PCR Testing.

The similar presentations in relapse of inflammatory bowel disease (IBD) and enteric infection pose substantial barriers to diagnosis and treatment. The objective of this study was to investigate the incidence, etiology, predictors, and treatment of enteric infection in patients with IBD. We reviewed the records of 214 patients with IBD who underwent 295 gastrointestinal pathogen panel and Clostridium difficile infection (CDI) polymerase chain reaction (PCR) stool tests during an exacerbation of symptoms. We collected baseline characteristics, PCR outcomes, and medication exposures. We tested for associations via the Chi-square test and the t-test. Logistic regression analysis was used to identify predictors of enteric infection. Of 295 PCR tests ordered during an exacerbation of symptoms, 38 (12.9%) were positive for CDI and 41 (13.8%) were positive for 14 other pathogens, with E. coli species as the most common. A previous history of CDI or colonic involvement of IBD predicted CDI, whereas a previous colectomy predicted negative testing for CDI. The majority with CDI (24, 63.2%) received oral vancomycin and 15 (37.5%) with other enteric pathogens were treated for their infection. Patients with CDI had a longer median length of hospital stay (8.5 versus 4 days, P = 0.041). Patients who tested negative for enteric infections were more likely to have IBD medications added or up-titrated (P = 0.027). Enteric infection was detected in 79 (26.8%) symptomatic patients with IBD , with CDI the most frequent followed by E. coli. Negative stool PCR testing was associated with changes in IBD management. Broad enteric PCR testing should be considered during relapse of IBD.

Medically Graded Honey Supplementation Formula to Preterm Infants as a Prebiotic: A Randomized Controlled Trial.

The aim of the study was to assess the effect of medically graded enteral honey supplementation on the intestinal microbiota, immune response, and somatic growth of preterm infants. A prospective randomized controlled trial was conducted on preterm infants with gestational age ≤34 weeks and postnatal age >3 days. After reaching 1/2 goal enteral feeds, medically graded bee honey was added to milk at a dose of 5, 10, 15, and 0 g/day for 2 weeks in groups A, B, C, and D, respectively. Anthropometric measurements, CD4 and CD8 cytokines, stool cultures, and stool polymerase chain reaction assays for molecular detection of microbiomes were performed at 0, 7, and 14 days of intervention. Analysis of variance test was used to detect differences among the 4 groups. A total of 40 subjects were enrolled; 10 in each arm of the study. Compared with group D, all 3 intervention groups demonstrated significant increase in weight (P < 0.0001). Head circumference increased in groups B and C (P = 0.0056). There were no changes in CD4 or CD8 cytokines (P = 0.24 and P = 0.11, respectively). Enterobacter stool colonization decreased in groups A and B (P = 0.002), whereas Bifidobacterium bifidum colony counts increased in groups A, B, and C (P = 0.002) and lactobacilli colony counts increased in group B (P < 0.0001). Applying real-time polymerase chain reaction, B bifidum and lactobacilli increased in group C (P < 0.0001). Supplementation of milk formula with medically graded honey was associated with changes in physical growth and colonic microbiota of preterm infants. Further studies are needed to examine the sustainability of these effects and associated long-term outcomes.

Clostridium difficile rates in asymptomatic and symptomatic hospitalized patients using nucleic acid testing

BackgroundThe Clostridium difficile rate in symptomatic patients represents both those with C. difficile infection (CDI) and those with colonization. To predict the extent of CDI overdiagnosis, we compared the asymptomatic colonization rate to the symptomatic positivity rate in hospitalized patients using nucleic acid testing. MethodsBetween July 2014 and April 2015, formed stool samples were collected from asymptomatic patients after admission to 3 hospital wards at the Stanford Hospital. Stool samples from symptomatic patients with suspected CDI in the same wards were collected for testing per provider order. The GeneXpert C. difficile tcdB polymerase chain reaction (PCR) assay (Cepheid, Sunnyvale, CA, USA) was performed on all stool samples and PCR cycle threshold was used as a measure of genomic equivalents. Chart review was performed to obtain clinical history and medication exposure. ResultsWe found an asymptomatic C. difficile carriage rate of 11.8% (43/365) (95% confidence interval [CI], 8.5–15.1%) and a positivity rate in symptomatic patients of 15.4% (54/351) (95% CI, 11.6–19.2%; P=0.19). The median PCR cycle thresholds was not significantly different between asymptomatic carriers and symptomatic positives (29.5 versus 27.3; P=0.07). Among asymptomatic patients, 11.6% (5/43) of carriers and 8.4% (27/322; P=0.56) of noncarriers subsequently became symptomatic CDI suspects within the same hospitalization. Single and multivariate analysis did not identify any demographic or clinical factors as being significantly associated with C. difficile carriage. ConclusionsAsymptomatic C. difficile carriage rate was similar to symptomatic positivity rate. This suggests the majority of PCR-positive results in symptomatic patients are likely due to C. difficile colonization. Disease-specific biomarkers are needed to accurately diagnose patients with C. difficile disease.

Community-acquired Escherichia coli Enteritis in Korean Children: The Clinical Application of a Stool Polymerase Chain Reaction Assay.

BackgroundAlthough Escherichia coli is a common cause of bacterial enteritis in Korea, reports on community-acquired E. coli enteritis in Korean children are scarce. This study aimed to determine the clinical characteristics and pathotype distribution of community-acquired E. coli enteritis diagnosed by a multiplex polymerase chain reaction (PCR) assay in Korean children.Materials and MethodsThe medical records of children aged 18 years or less who were diagnosed with acute gastroenteritis by the attending physician between 2013 and 2016 were retrospectively reviewed. The clinical characteristics of children diagnosed with E. coli enteritis were investigated and compared with those diagnosed with Salmonella enteritis. E. coli and Salmonella infections were diagnosed by a stool PCR assay.ResultsAmong 279 children, in whom PCR assays for E. coli and Salmonella spp. were performed, Salmonella enteritis and E. coli enteritis were diagnosed in 43 (15.4%) and 39 (14.0%) children, respectively. Among the 39 children with E. coli enteritis, enteropathogenic E. coli (n=21, 53.8%) and enteroaggregative E. coli (n=15, 38.4%) were the most common causative agents. Empirical antibiotics were administered to 33 (84.6%) children. A total of 31 (79.5%) children developed fever, and 25 (80.6%) of them had the fever for 3 days or less, which resolved a median of 1 day (range 0-3 days) after hospitalization. The most frequent gastrointestinal symptom was diarrhea (n=36, 92.3%). Significantly more children with E. coli enteritis were aged 2 years or less as compared with those with Salmonella enteritis (41.0% vs. 21.9%, P = 0.021). Children with Salmonella enteritis more frequently complained of fever (97.7% vs. 79.5%, P = 0.012), abdominal pain (90.7% vs. 64.1%, P = 0.004), and hematochezia (46.5% vs. 10.3%, P <0.001) than those with E. coli enteritis. Erythrocyte sedimentation rate and C-reactive protein levels were significantly higher in children with Salmonella enteritis than those with E. coli enteritis (P <0.001).ConclusionEnteropathogenic E. coli was the most frequent pathotype in Korean children with E. coli enteritis that caused mild clinical symptoms. A stool PCR assay for E. coli may be useful for epidemiological purpose and for an early diagnosis of E. coli enteritis.

Receipt of Antibiotics in Hospitalized Patients and Risk for Clostridium difficile Infection in Subsequent Patients Who Occupy the Same Bed

ObjectiveTo assess whether receipt of antibiotics by prior hospital bed occupants is associated with increased risk for CDI in subsequent patients who occupy the same bed.Design, Setting, and ParticipantsThis is a retrospective cohort study of adult patients hospitalized in any 1 of 4 facilities between 2010 and 2015. Patients were excluded if they had recent CDI, developed CDI within 48 hours of admission, had inadequate follow-up time, or if their prior bed occupant was in the bed for less than 24 hours.Main Outcomes and MeasuresThe primary exposure was receipt of non-CDI antibiotics by the prior bed occupant and the primary outcome was incident CDI in the subsequent patient to occupy the same bed. Incident CDI was defined as a positive result from a stool polymerase chain reaction for the C difficile toxin B gene followed by treatment for CDI. Demographics, comorbidities, laboratory data, and medication exposures are reported.ResultsAmong 100 615 pairs of patients who sequentially occupied a given hospital bed, there were 576 pairs (0.57%) in which subsequent patients developed CDI. Receipt of antibiotics in prior patients was significantly associated with incident CDI in subsequent patients (log-rank P < .01). This relationship remained unchanged after adjusting for factors known to influence risk for CDI including receipt of antibiotics by the subsequent patient (adjusted hazard ratio [aHR], 1.22; 95% CI, 1.02-1.45) and also after excluding 1497 patient pairs among whom the prior patients developed CDI (aHR, 1.20; 95% CI, 1.01-1.43). Aside from antibiotics, no other factors related to the prior bed occupants were associated with increased risk for CDI in subsequent patients.Conclusions and RelevanceReceipt of antibiotics by prior bed occupants was associated with increased risk for CDI in subsequent patients. Antibiotics can directly affect risk for CDI in patients who do not themselves receive antibiotics.

Diagnostic value of the Vesikari Scoring System for predicting the viral or bacterial pathogens in pediatric gastroenteritis.

PurposeTo evaluate the diagnostic value of the Vesikari Scoring System (VSS) as an early predictor of pathogens in children with acute gastroenteritis (AG).MethodsIn this retrospective study, the VSS score, absolute neutrophil count (ANC), and C-reactive protein (CRP) levels were analyzed in 107 hospitalized children with AG, aged 6 months to 17 years. Patients were divided into nonspecific, viral, and bacterial groups according to the pathogens detected using a multiplex polymerase chain reaction (PCR) test.ResultsPatients in the bacterial group had significantly higher CRP values and VSS scores compared to those in the viral group and significantly higher VSS scores compared to those in the nonspecific group (P<0.05). Patients in the viral group had significantly higher VSS scores than those in the nonspecific group (P<0.05). Logistic regression analysis revealed that VSS was the most effective diagnostic tool for predicting the type of pathogen (P<0.05). The area under the receiver operating characteristics curve of VSS was significantly greater than that for ANC and CRP (P<0.05). At a cutoff point of 10 in the VSS, an acceptable diagnostic accuracy could be achieved for distinguishing between bacterial and viral pathogens in AG.ConclusionVSS can be considered a useful and reliable infectious marker for pediatric gastroenteritis. VSS may be a good early predictor of the type of pathogen, enabling development of a treatment plan before results from a stool culture or PCR test are available.

Serum Anti-Cryptosporidial gp15 Antibodies in Mothers and Children Less than 2 Years of Age in India.

Little is known about the type and longevity of the humoral response to cryptosporidial infections in developing countries. We evaluated serum antibody response to Cryptosporidium gp15 in 150 sets of maternal, preweaning and postinfection/end-of-follow-up sera from children followed up to 2 years of age to determine the influence of maternal and preweaning serological status on childhood cryptosporidiosis. Fifty two percent (N = 78) of mothers and 20% (N = 30) of children were seropositive preweaning. However, most positive preweaning samples from children were collected early in life indicating transplacental transfer and subsequent rapid waning of antibodies. Although 62% (N = 94) of children had a parasitologically confirmed cryptosporidial infection (detected by stool polymerase chain reaction) during the follow-up, only 54% (N = 51) of children were seropositive postinfection. Given there were striking differences in seropositivity depending on when the sample was collected, even though Cryptosporidium was detected in the stool of the majority of the children, this study indicates that antibodies wane rapidly. During follow-up, the acquisition or severity of cryptosporidial infections was not influenced by maternal (P = 0.331 and 0.720, respectively) as well as the preweaning serological status of the child (P = 0.076 and 0.196, respectively).

Clinical utility of stool polymerase chain reaction in pediatric patients with suspected enteroviral meningitis

The purpose of this study was to evaluate whether stool polymerase chain reaction (PCR) has a higher clinical sensitivity for detecting enterovirus compared with cerebrospinal fluid (CSF) PCR in pediatric patients suspected to have enteroviral meningitis. We retrospectively reviewed 139 pediatric patients with enteroviral meningitis diagnosed in our hospital during 2010–2012. Enteroviral meningitis was diagnosed based on detection of virus in CSF and/or stool samples in aseptic meningitis patients. Patients were divided into definitive enteroviral meningitis (positive CSF PCR) and highly probable enteroviral meningitis (negative CSF PCR, but positive stool PCR) groups. The clinical characteristics of the two groups were compared to identify the characteristics of patients with highly probable enteroviral meningitis. We also analyzed the influence of sampling time on the PCR results of the two specimen types. Patients with highly probable enteroviral meningitis had a lower white blood cell count in CSF ( P P = 0.03) than did patients with definitive enteroviral meningitis. The CSF enterovirus positivity rate was lower in CSF specimens obtained > 1 day after clinical onset, whereas the majority of stool samples were PCR positive throughout the course of the disease. Our results suggest that PCR of stool specimens may be useful in pediatric patients with suspected enteroviral meningitis, particularly when the duration of symptoms is >1 day and/or a lower degree of CSF pleocytosis is observed.

Risk factors for cryptosporidiosis among children in a semi urban slum in southern India: a nested case-control study.

The risk factors for acquisition of cryptosporidial infection in resource-poor settings are poorly understood. A nested case-control study was conducted to assess factors associated with childhood cryptosporidiosis (detected by stool polymerase chain reaction) in an endemic, Indian slum community using data from two community-based studies with 580 children followed prospectively until their second birthday. Factors were assessed for overall cryptosporidiosis (N = 406), and for multiple (N = 208), asymptomatic (N = 243), and symptomatic (N = 163) infections, respectively. Presence of older siblings (odds ratio [OR] = 1.88, P = 0.002) and stunting at 6 months of age (OR = 1.74, P = 0.019) were important risk factors for childhood cryptosporidiosis. Always boiling drinking water before consumption, the use of a toilet by all members of the family, and maternal age ≥ 23 years were protective. These results provide insights into acquisition of childhood cryptosporidiosis in settings with poor environmental sanitation, contaminated public water supply systems, and close human-animal contact. Disease control strategies will require a multifaceted approach.

A Cross-Sectional Study of Helicobacter Infection Among Laboratory Animals and Animal Research Workers

A Cross-Sectional Study of Helicobacter Infection Among Laboratory Animals and Animal Research Workers

Evaluation of Noninvasive Versus Invasive Techniques for the Diagnosis of Helicobacter pylori Infection

Helicobacter pylori is one of the most common bacterial strains causing chronic infections, affecting over one half of the world's population. There is increasing interest in noninvasive methods for diagnosing H. pylori infection. The aim of the study was to evaluate 3 different noninvasive methods of diagnosis: the stool antigen test (HpSA), the serum antibody test, and the stool-polymerase chain reaction (PCR) test as against invasive methods based on histopathologic diagnosis. Gastric biopsies were obtained during endoscopy. Sections were stained with hematoxylin and eosin and Giemsa stain. Serum samples were tested for H. pylori antibody using an enzyme-linked immnunosorbent assay kit for the semiquantitative determination of IgG antibodies; stool samples were tested for H. pylori antigen using polyclonal enzyme-linked immnunosorbent assay kits. DNA samples from stool specimens were extracted, followed by PCR for the detection of H. pylori UreA. The results revealed that 18/19 (94.7%) patients were positive for H. pylori infection as detected by Giemsa stain, and 84.2% were positive on the basis of hematoxylin and eosin stain, with a sensitivity and specificity of 88.9% and 100%, respectively. Diagnosis by noninvasive methods, including the serum antibody test, revealed a sensitivity and positive predictive value of 88.9% and 94.2%, respectively, whereas the stool antigen test recorded a sensitivity and positive predictive value of 72.2% and 92.9%, respectively. The stool-PCR test recorded a sensitivity of 72.2% and specificity of 100%. Among the noninvasive methods for diagnosis of H. pylori infection, the 3 methods used in this study recorded promising results, including good sensitivity, which was the highest in the serum antibody test, whereas the stool-PCR test recorded excellent specificity.