Dataset Information

Prevalence and molecular subtyping of Blastocystis in patients with Clostridium difficile infection, Singapore.

ABSTRACT:

Background

Blastocystis is a common anaerobic colonic protist in humans with controversial pathogenicity. Clostridium difficile (C. difficile) is the commonest cause of infectious diarrhea in healthcare settings. The prevalence and subtype (ST) characteristics of Blastocystis in patients with C. difficile infection (CDI) are rarely documented. Therefore, the present study was conducted to investigate the prevalence and subtype characteristics of Blastocystis in patients with suspicion of CDI in Singapore.

Methods

Fecal samples were collected from 248 patients presenting with suspected CDI from a single tertiary hospital in Singapore. C. difficile was diagnosed through positive glutamate dehydrogenase (GDH) with or without toxin A/B using enzyme immunoassay methods. The prevalence and subtype genetic characteristics of Blastocystis were determined by polymerase chain reaction (PCR) amplification and analysis of the barcode region of the SSU rRNA gene.

Results

The proportion of C. difficile in patients with healthcare-associated diarrhea in this study was 44% (109/248). Among the 109 C. difficile-positive patients, 59 (54.1%, 59/109) tested positive for toxigenic C. difficile, which was considered CDI. Based on the sequence analyses of the barcode region of the SSU rRNA gene, 10.1% (25/248) of the patients were found to be Blastocystis-positive, and three subtypes were identified: ST7 (64%, 16/25), ST1 (20%, 5/25), and ST3 (16%, 4/25). Remarkably, we found five patients with Blastocystis and C. difficile coinfection, and further subtype analysis showed two with ST7, two with ST1, and one with ST3.

Conclusions

To the best of our knowledge, this is the first study to investigate the subtype distributions of Blastocystis in patients with CDI in Singapore. We found ST7 to be the predominant subtype in diarrheal patients. The pathogenicity of ST7 has been strongly suggested in previous in vitro and mouse model experiments, further confirming its potential pathogenicity to humans.

SUBMITTER: Deng L

PROVIDER: S-EPMC8142501 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:OBJECTIVE: To examine the rate of Clostridium difficile infection (CDI) and hospital-associated outcomes in a national cohort of hospitalized patients with chronic kidney disease (CKD) and assess the impact of long-term dialysis on outcome in these patients. PATIENTS AND METHODS: Data for January 1, 2005, through December 31, 2009 were obtained from the National Hospital Discharge Survey, which includes information on patient demographics, diagnoses, procedures, and discharge types. Data collected and analyzed for this study included age, sex, race, admission type (urgent or emergent combined vs elective), any colectomy diagnosis, length of stay, type of discharge, and mortality. International Classification of Diseases, Ninth Revision, Clinical Modification codes were utilized to identify CKD patients and CDI events. Weighted analysis was performed using JMP version 9. RESULTS: An estimated 162 million adults were hospitalized during 2005-2009, and 8.03 million (5%) had CKD (median age, 71 years). The CDI rate in CKD patients was 1.49% (0.119 million) compared with 0.70% (1.14 million) in patients without CKD (P<.001). Patients with CKD who were undergoing long-term dialysis were more than 2 times as likely to develop CDI than non-CKD patients and 1.33 times more likely than CKD patients not undergoing dialysis (all P<.001). In a weighted multivariate analysis adjusting for sex and comorbidities, patients with CKD and CDI had longer hospitalization, higher colectomy rate (adjusted odds ratio [aOR], 2.30; 95% confidence interval [CI], 2.14-2.47), dismissal to a health care facility (aOR, 2.22; 95% CI, 2.19-2.25), and increased in-hospital mortality (aOR, 1.55; 95% CI, 1.52-1.59; all P<.001) as compared with CKD patients without CDI. Patients with CKD who were undergoing long-term dialysis did not have worse outcomes as compared with CKD patients who were not undergoing long-term dialysis. CONCLUSION: These data suggest that patients with CKD have a higher risk of CDI and increased hospital-associated morbidity and mortality. Future prospective studies are needed to confirm these findings and to identify effective CDI prevention in CKD patients, who appear to have an increased risk of CDI acquisition.

Project description:IntroductionAs data from Clostridium difficile infection (CDI) in intensive care unit (ICU) are still scarce, our objectives were to assess the morbidity and mortality of ICU-acquired CDI.MethodsWe compared patients with ICU-acquired CDI (watery or unformed stools occurring ? 72 hours after ICU admission with a stool sample positive for C. difficile toxin A or B) with two groups of controls hospitalized at the same time in the same unit. The first control group comprised patients with ICU-acquired diarrhea occurring ? 72 hours after ICU admission with a stool sample negative for C. difficile and for toxin A or B. The second group comprised patients without any diarrhea.ResultsAmong 5,260 patients, 512 patients developed one episode of diarrhea. Among them, 69 (13.5%) had a CDI; 10 (14.5%) of them were community-acquired, contrasting with 12 (17.4%) that were hospital-acquired and 47 (68%) that were ICU-acquired. A pseudomembranous colitis was associated in 24/47 (51%) ICU patients. The median delay between diagnosis and metronidazole administration was one day (25th Quartile; 75th Quartile (0; 2) days). The case-fatality rate for patients with ICU-acquired CDI was 10/47 (21.5%), as compared to 112/443 (25.3%) for patients with negative tests. Neither the crude mortality (cause specific hazard ratio; CSHR = 0.70, 95% confidence interval; CI 0.36 to 1.35, P = 0.3) nor the adjusted mortality to confounding variables (CSHR = 0.81, 95% CI 0.4 to 1.64, P = 0.6) were significantly different between CDI patients and diarrheic patients without CDI. Compared to the general ICU population, neither the crude mortality (SHR = 0.64, 95% CI 0.34 to 1.21, P = 0.17), nor the mortality adjusted to confounding variables (CSHR = 0.71, 95% confidence interval (CI) 0.38 to 1.35, P = 0.3), were significantly different between the two groups. The estimated increase in the duration of stay due to CDI was 8.0 days ± 9.3 days, (P = 0.4) in comparison to the diarrheic population, and 6.3 days ± 4.3 (P = 0.14) in comparison to the general ICU population.ConclusionsIf treated early, ICU-acquired CDI is not independently associated with an increased mortality and impacts marginally the ICU length of stay.

Project description:ImportanceClostridium difficile is a major cause of health care-associated infection, but disagreement between diagnostic tests is an ongoing barrier to clinical decision making and public health reporting. Molecular tests are increasingly used to diagnose C difficile infection (CDI), but many molecular test-positive patients lack toxins that historically defined disease, making it unclear if they need treatment.ObjectiveTo determine the natural history and need for treatment of patients who are toxin immunoassay negative and polymerase chain reaction (PCR) positive (Tox-/PCR+) for CDI.Design, setting, and participantsProspective observational cohort study at a single academic medical center among 1416 hospitalized adults tested for C difficile toxins 72 hours or longer after admission between December 1, 2010, and October 20, 2012. The analysis was conducted in stages with revisions from April 27, 2013, to January 13, 2015.Main outcomes and measuresPatients undergoing C difficile testing were grouped by US Food and Drug Administration-approved toxin and PCR tests as Tox+/PCR+, Tox-/PCR+, or Tox-/PCR-. Toxin results were reported clinically. Polymerase chain reaction results were not reported. The main study outcomes were duration of diarrhea during up to 14 days of treatment, rate of CDI-related complications (ie, colectomy, megacolon, or intensive care unit care) and CDI-related death within 30 days.ResultsTwenty-one percent (293 of 1416) of hospitalized adults tested for C difficile were positive by PCR, but 44.7% (131 of 293) had toxins detected by the clinical toxin test. At baseline, Tox-/PCR+ patients had lower C difficile bacterial load and less antibiotic exposure, fecal inflammation, and diarrhea than Tox+/PCR+ patients (P < .001 for all). The median duration of diarrhea was shorter in Tox-/PCR+ patients (2 days; interquartile range, 1-4 days) than in Tox+/PCR+ patients (3 days; interquartile range, 1-6 days) (P = .003) and was similar to that in Tox-/PCR- patients (2 days; interquartile range, 1-3 days), despite minimal empirical treatment of Tox-/PCR+ patients. No CDI-related complications occurred in Tox-/PCR+ patients vs 10 complications in Tox+/PCR+ patients (0% vs 7.6%, P < .001). One Tox-/PCR+ patient had recurrent CDI as a contributing factor to death within 30 days vs 11 CDI-related deaths in Tox+/PCR+ patients (0.6% vs 8.4%, P = .001).Conclusions and relevanceAmong hospitalized adults with suspected CDI, virtually all CDI-related complications and deaths occurred in patients with positive toxin immunoassay test results. Patients with a positive molecular test result and a negative toxin immunoassay test result had outcomes that were comparable to patients without C difficile by either method. Exclusive reliance on molecular tests for CDI diagnosis without tests for toxins or host response is likely to result in overdiagnosis, overtreatment, and increased health care costs.