The role of gut inflammation in recurrent Clostridium difficile-associated disease

Melatonin as an Antimicrobial Adjuvant and Anti-Inflammatory for the Management of Recurrent Clostridioides difficile Infection

Background:Clostridioides difficile (C. difficile) infection (CDI) is strongly associated with inflammation and has the potential to cause recurrent infections. Pre-clinical data suggest that melatonin has beneficial effects in the gastrointestinal tract due to its anti-inflammatory and antibacterial properties. This analysis examines the association between melatonin and the risk of recurrent CDI. Methods: A retrospective cohort study was conducted among patients with an inpatient diagnosis of CDI along with a positive C. difficile polymerase chain reaction (PCR) or enzyme immunoassay (EIA) test result. Patients were followed until the first study end point (death) or the first instance of recurrent infection. Propensity-score weighting was utilized accounting for confounding factors and weighted Cox models were estimated. Results: A total of 24,782 patients met the inclusion criteria, consisting of 3457 patients exposed to melatonin and 21,325 patients with no melatonin exposure. The results demonstrate that those exposed to melatonin were associated with a 21.6% lower risk of recurrent CDI compared to patients without melatonin exposure (HR = 0.784; 95% CI = 0.674-0.912). Conclusion: Our results demonstrate a decreased rate of recurrent CDI in patients exposed to melatonin. Further research on melatonin as an antimicrobial adjuvant and anti-inflammatory is warranted for the management of recurrent CDI.

Host response to Clostridium difficile infection: Diagnostics and detection

Clostridium difficile infection (CDI) is a significant healthcare concern worldwide, and C. difficile is recognised as the most frequent aetiological agent of infectious healthcare-associated diarrhoea in hospitalised adult patients. The clinical manifestation of CDI varies from self-limited diarrhoea to life-threatening colitis. Such a broad disease spectrum can be explained by the impact of host factors. Currently, a complex CDI aetiology is widely accepted, acknowledging the interaction between bacteria and the host. C. difficile strains producing clostridial toxins A and B are considered toxigenic and can cause disease; those not producing the toxins are non-pathogenic. A person colonised with a toxigenic strain will not necessarily develop CDI. It is imperative to recognise patients with active disease from those only colonised with this pathogen and to implement appropriate treatment. This can be achieved by diagnostics that rely on host factors specific to CDI. This review will focus on major aspects of CDI pathogenesis and molecular mechanisms, describing host factors in disease progression and assessment of the host response in order to facilitate the development of CDI-specific diagnostics.

Recurrent Clostridium difficile infection: From colonization to cure

Clostridium difficile infection (CDI) is increasingly prevalent, dangerous and challenging to prevent and manage. Despite intense national and international attention the incidence of primary and of recurrent CDI (PCDI and RCDI, respectively) have risen rapidly throughout the past decade. Of major concern is the increase in cases of RCDI resulting in substantial morbidity, morality and economic burden. RCDI management remains challenging as there is no uniformly effective therapy, no firm consensus on optimal treatment, and reliable data regarding RCDI-specific treatment options is scant. Novel therapeutic strategies are critically needed to rapidly, accurately, and effectively identify and treat patients with, or at-risk for, RCDI. In this review we consider the factors implicated in the epidemiology, pathogenesis and clinical presentation of RCDI, evaluate current management options for RCDI and explore novel and emerging therapies.

Clostridium difficile recurrence is characterized by pro-inflammatory peripheral blood mononuclear cell (PBMC) phenotype

Clostridium difficile infection (CDI) is a prevalent nosocomial and increasingly community-acquired problem. Little is known about the productive cellular response in patients. We used flow cytometry to define inflammatory (Th1 and Th17) and regulatory [Foxp3(+) T-regulatory (Treg)] cells present in circulating peripheral blood mononuclear cells (PBMC) from CDI patients. We consented 67 inpatients that tested either positive or negative for CDI and 16 healthy controls and compared their PBMC phenotypes. PBMC were collected, isolated, and stained for CD3, CD8 and either IL17 (Th17), IFN-γ (Th1) or Foxp3 (Treg) and analysed using flow cytometry. Twenty thousand events were collected in the lymphocyte gate (gate 1) and T-cell phenotypes were defined. CDI patients who clear the primary initial infection have greater numbers of non-CD3 PBMC. CDI patients who develop recurrence of CDI have a greater percentage of CD3(+)CD8(+), CD3(+)CD4(+)Foxp3 and fewer low granular CD3(-)Foxp3(+) PBMC. These patients have greater numbers of IFN-γ-producing lymphocytes, as well as PBMC phenotypes represented by increased IFN-γ- and IL17-co-expressing CD4(+)CD3(+). This initial pro-inflammatory phenotype decreases with repeated recurrence, demonstrating importance of timing of sample collection and history of symptoms. Patients with a history of recurrence had increased Foxp3(+)CD3(+)CD4(+) and IL17(+)CD3(+)CD4(+) populations. Hence, CDI recurrence is hallmarked by greater numbers of circulating CD3(+) lymphocytes skewed towards a Th1/Th17 inflammatory population as well as possible immune plasticity (Th17/Treg).

Ribotype 027 Clostridium difficile infections with measurable stool toxin have increased lactoferrin and are associated with a higher mortality

We evaluated clinical and diagnostic indicators of severe C. difficile infection (CDI) and their association with poor clinical outcome. A total of 210 patients positive according to PCR (toxin B: tcdB) were included, with patients having a median age of 62 years and a Charlson co-morbidity index (CI) score of 5. Ninety-one percent (n = 191) were positive by toxigenic culture and 61 % (n = 129) had stool toxin. Toxin-positive patients had significantly higher fecal lactoferrin (mean 316 μg/g versus 106 μg/g stool; p < 0.0001). Forty percent of patients (n = 85) were infected with ribotype 027 and significantly more of these patients had measurable stool toxin (79 % vs. 50 %; p < 0.0001). The mean fecal lactoferrin was significantly higher for toxin-positive 027 CDI compared with the 027 toxin-negative group (317 vs 60 μg/g; p = 0.0014). Ribotype 027 CDI with stool toxin showed a higher all-cause, 100-day mortality compared with non-027 with stool toxin (36 % vs 18 %; p = 0.017). Logistic regression univariate analysis for odds ratio (OR) and p values revealed that age (OR = 1.1), intensive care unit treatment (OR = 2.7), CI (OR = 1.2), 027 CDI (OR = 2.1), white blood cell count (OR = 1.0), albumin level (OR = 0.1), and stool toxin-positive 027 CDI (OR = 2.5) were significantly associated with 100-day mortality (p < 0.05). In conclusion, CDI PCR-positive patients with 027 infection and stool toxin have increased lactoferrin and are at an increased risk of death.

Intestinal inflammatory biomarkers and outcome in pediatric Clostridium difficile infections

OBJECTIVES

To identify specific fecal biomarkers for symptomatic Clostridium difficile infection and predictors of poor outcomes.

STUDY DESIGN

We enrolled 65 children with positive C difficile testing (cases) and 37 symptomatic controls. We also analyzed stool samples from colonized and non-colonized asymptomatic children. We performed enzyme immunoassays to determine fecal interleukin (IL)-8, lactoferrin, and phosphorylated-p38 protein concentrations, and quantitative polymerase chain reaction to determine IL-8 and chemokine ligand (CXCL)-5 RNA relative transcript abundances, and C difficile bacterial burden.

RESULTS

Of 68 asymptomatic controls, 16 were colonized with C difficile. Phosphorylated-p38 was specific for C difficile infection but lacked sensitivity. Fecal cytokines were elevated in samples from symptomatic children, whether cases or controls. In children with C difficile infection, fecal CXCL-5 and IL-8 messenger RNA abundances at diagnosis correlated with persistent diarrhea after 5 days of C difficile infection therapy and with treatment with vancomycin. When children with concomitant viral gastroenteritis were excluded, these correlations persisted. Time-to-diarrhea resolution was significantly longer in patients with elevated fecal cytokines at diagnosis. A logistic regression model identified high CXCL-5 messenger RNA abundance as the only predictor of persistent diarrhea. Conversely, fecal C difficile bacterial burden was not different in symptomatic and asymptomatic children and did not correlate with any clinical outcome measure.

CONCLUSIONS

Fecal inflammatory cytokines may be useful in distinguishing C difficile colonization from disease and identifying children with C difficile infection likely to have prolonged diarrhea.