Evaluation of antigen‐positive toxin‐negative enzyme immunoassay results for the diagnosis of toxigenic Clostridium difficile infection

Akamatsu, Yukinobu; Morishita, Shota; Chikumi, Hiroki; Okamoto, Ryo; Okada, Kensaku; Kitaura, Tsuyoshi; Miyake, Naritomo; Yamaguchi, Kosuke; Nakamoto, Masaki; Shimohiro, Hisashi; Takata, Miyako; Yamasaki, Akira; Burioka, Naoto; Shimizu, Eiji

doi:10.2152/jmi.65.131

Cited by 4 publications

(5 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Given the prevalence of low-toxin strains in clinical settings, both in our study and in other reports [11,38,58], failure to detect toxin in the stool of C. difficile -positive patients should be interpreted with caution. In their study, Reigadas et al reported 12.7% of CDI cases (n = 26 of 204 total) would have been missed due to a lack of clinical suspicion despite these patients exhibiting mild-to-moderate symptoms [59].…”

Section: Discussionmentioning

confidence: 58%

Low-Toxin Clostridioides difficile RT027 Strains Exhibit Robust Virulence

Anwar

Roxas

Shehab

et al. 2022

Preprint

View full text Add to dashboard Cite

Clostridioides difficile is a leading cause of healthcare-associated infections worldwide. Currently, there is lack of consensus on a single optimal diagnostic method for C. difficile infection (CDI). Nucleic acid amplification tests (NAAT) that detect toxin genes are highly sensitive, but their specificity limitations could inflate CDI rates. Alternate multi-step diagnostic algorithms emphasize the detection of C. difficile toxins TcdA/TcdB, and are premised on the rationale that stool toxin-negative (Tox-) CDI patients have less severe disease, shorter diarrhea duration, and fewer disease complications. There have been no systematic assessments, however, of the virulence of C. difficile strains from Tox-/NAAT+ (discrepant) specimens. In our prospective analysis of 1243 C. difficile-positive patient stool specimens from three Southern Arizona hospitals, 31% were discrepant. Ribotype 027 (RT027) strains were recovered from 221 specimens; of these, 23% were discrepant. Post-culture, RT027 strains produced a range of toxin amounts including levels lower than that of the non-epidemic strain CD630. These low-toxin RT027 (LT-027) strains harbored both tcdA and tcdB genes, and their culture supernatants were cytotoxic to cultured fibroblasts. We confirmed robust colonization and virulence of a subset of LT-027 strains using multiple rodent models; lethality in animals infected with LT-027 strains was comparable to that potentiated by a high-toxin RT027 strain. Comparative genomics and proteomics analyses of several LT-027 strains identified unique genes and altered protein abundances relative to closely-related high-toxin strains. Collectively our data highlight the robust virulence and clinical relevance of low-toxin-producing, RT027 C. difficile isolates.

show abstract

Section: Discussionmentioning

confidence: 58%

Low-Toxin Clostridioides difficile RT027 Strains Exhibit Robust Virulence

Anwar

Roxas

Shehab

et al. 2022

Preprint

View full text Add to dashboard Cite

show abstract

“…Our findings indicate that up to 69% of the GDH+/Toxin-specimens nevertheless harbor toxigenic C. difficile. Similarly, Akamatsu et al reported toxigenic C. difficile to be present in 63.2% of GDH+/Toxin-specimens (45). The CDC estimates that discrepant specimens (NAAT+/Toxin-) constitute 31% of the national sampling set (25), although regional differences may be masked in national averages.…”

Section: Discussionmentioning

confidence: 99%

Prevalence of diagnostically-discrepant Clostridioides difficile clinical specimens: insights from longitudinal surveillance

Anwar,

Clark,

Lindsey

et al. 2023

Front. Med.

View full text Add to dashboard Cite

BackgroundClostridioides difficile Infection (CDI) is a healthcare-associated diarrheal disease prevalent worldwide. A common diagnostic algorithm relies on a two-step protocol that employs stool enzyme immunoassays (EIAs) to detect the pathogen, and its toxins, respectively. Active CDI is deemed less likely when the Toxin EIA result is negative, even if the pathogen-specific EIA is positive for C. difficile. We recently reported, however, that low-toxin-producing C. difficile strains recovered from Toxin-negative (‘discrepant’) clinical stool specimens can be fully pathogenic, and cause lethality in a rodent CDI model. To document frequency of discrepant CDI specimens, and evaluate C. difficile strain diversity, we performed longitudinal surveillance at a Southern Arizona tertiary-care hospital.MethodsDiarrheic stool specimens from patients with clinical suspicion of CDI were obtained over an eight-year period (2015–2022) from all inpatient and outpatient Units of a > 600-bed Medical Center in Southern Arizona. Clinical laboratory EIA testing identified C. difficile-containing specimens, and classified them as Toxin-positive or Toxin-negative. C. difficile isolates recovered from the stool specimens were DNA fingerprinted using an international phylogenetic lineage assignment system (“ribotyping”). For select isolates, toxin abundance in stationary phase supernatants of pure cultures was quantified via EIA.ResultsOf 8,910 diarrheic specimens that underwent diagnostic testing, 1733 (19.4%) harbored C. difficile. Our major findings were that: (1) C. difficile prevalence and phylogenetic diversity was stable over the 8-year period; (2) toxigenic C. difficile was recovered from 69% of clinically Tox-neg (‘discrepant’) specimens; (3) the six most prevalent USA ribotypes were recovered in significant proportions (>60%) from Tox-neg specimens; and (4) toxin–producing C. difficile recovered from discrepant specimens produced less toxin than strains of the same ribotype isolated from non-discrepant specimens.ConclusionOur study highlights the dominance of Toxin EIA-negative CDI specimens in a clinical setting and the high frequency of known virulent ribotypes in these specimens. Therefore, a careful reevaluation of the clinical relevance of diagnostically-discrepant specimens particularly in the context of missed CDI diagnoses and C. difficile persistence, is warranted.

show abstract

“…In our study in 16% the samples, GDH was positive without toxin production. In a study done by Akamatsu et al 24 , out of the 356 GDH positive/ toxin negative patients, cultures were done in 220 samples and toxin producing C. difficile was obtained from 139 (63.2%) samples. 24 Therefore such population who are GDH positive/toxin negative, should be monitored carefully.…”

Section: Discussionmentioning

confidence: 99%

“…In a study done by Akamatsu et al 24 , out of the 356 GDH positive/ toxin negative patients, cultures were done in 220 samples and toxin producing C. difficile was obtained from 139 (63.2%) samples. 24 Therefore such population who are GDH positive/toxin negative, should be monitored carefully. Also, the effect of C. difficile colonization varies in different patients (asymptomatic carrier state to fulminant colitis and death).…”

Section: Discussionmentioning

confidence: 99%

Antibiotic-Associated Clostridium difficile Diarrhoea in Tertiary Care Hospital – A Study from Western India

Bhatawadekar¹,

Yadav²,

Babu³

et al. 2023

J. Pure Appl. Microbiol.

View full text Add to dashboard Cite

Antibiotic-associated Clostridium difficile (CD) diarrhoea is one of the common causes of healthcare-acquired infection. Cephalosporins, piperacillin-tazobactam and aminoglycosides are the common antibiotics which have the maximum chances of producing Clostridium difficile infection (CDI). Most Asian countries have easy accessibility to many of these antibiotics without prescription. Broad spectrum antibiotics have been indiscriminately used as empirical therapy over the last two decades which has resulted in an increased risk of C. difficile infection. In India, the prevalence of CDI is highly underestimated. This study aims to understand the prevalence, risk factors and comorbidities associated with CD diarrhoea in a tertiary care hospital from western India. 196 patients were included in the study who were diagnosed with antibiotic-associated diarrhoea (AAD) clinically. Stool samples collected were processed for anaerobic culture of C. difficile and immunochromatography test was done to detect C. difficile toxins A and B. The comorbidities associated as well as the use of antibiotics like cephalosporin or proton pump inhibitors were also noted for the patients with CDI. 32 samples yielded CD (16%), out of which toxin production was detected only in 16 isolates. The prevalence rate of CDI in our hospital was 5%. Most of the patients had history of chronic illnesses like diabetes mellitus, chronic kidney disease, ischemic heart disease, systemic hypertension, autoimmune diseases, or malignancy. Avoiding empirical therapy with antibiotics prone to cause AAD, Antimicrobial stewardship programme with proper infection control practices and epidemiological surveillance of CDI will help to reduce the burden of CDI in our country.

show abstract

Evaluation of antigen‐positive toxin‐negative enzyme immunoassay results for the diagnosis of toxigenic Clostridium difficile infection

Cited by 4 publications

References 24 publications

Low-Toxin Clostridioides difficile RT027 Strains Exhibit Robust Virulence

Low-Toxin Clostridioides difficile RT027 Strains Exhibit Robust Virulence

Prevalence of diagnostically-discrepant Clostridioides difficile clinical specimens: insights from longitudinal surveillance

Antibiotic-Associated Clostridium difficile Diarrhoea in Tertiary Care Hospital – A Study from Western India

Contact Info

Product

Resources

About