Clostridium difficile Diarrhea in the Elderly: Current Issues and Management Options

Pharmacokinetic analysis of an extended-pulsed fidaxomicin regimen for the treatment of Clostridioides (Clostridium) difficile infection in patients aged 60 years and older in the EXTEND randomized controlled trial

BACKGROUND

Fidaxomicin is a recommended treatment for Clostridioides difficile infection (CDI) and reduces CDI recurrence incidence versus vancomycin. An extended-pulsed fidaxomicin (EPFX) regimen further reduces recurrence frequency. However, the pharmacokinetic profile of fidaxomicin in an EPFX regimen is unknown.

OBJECTIVES

To evaluate plasma and stool concentrations of fidaxomicin and its metabolite, OP-1118, after EPFX administration for CDI.

METHODS

In the Phase 3b/4 EXTEND trial, patients aged ≥60 years with toxin-confirmed CDI were randomized to receive EPFX (oral fidaxomicin twice daily, Days 1-5; once daily on alternate days, Days 7-25). Fidaxomicin and OP-1118 concentrations were determined using post-dose plasma samples obtained on Days 5 ± 1, 12 ± 1 and 25/26, and post-dose stool samples obtained on Days 5 ± 1, 12 ± 1 and 26 ± 1.

RESULTS

Plasma samples from 14 patients were included in the pharmacokinetic analysis; 12 of these patients provided stool samples. Median (range) plasma concentrations of fidaxomicin on Day 5 ± 1 and Day 25/26 were 0.0252 (0.0038-0.1220) mg/L and 0.0069 (0-0.0887) mg/L, respectively, and those of OP-1118 were 0.0648 (0.0142-0.3250) mg/L and 0.0206 (0-0.3720) mg/L, respectively. Median (range) stool concentrations of fidaxomicin and OP-1118 on Day 26 ± 1 were 272.5 (0-524) mg/kg and 280.5 (0-1120) mg/kg, respectively.

CONCLUSIONS

EPFX treatment maintained fidaxomicin stool concentrations above the C. difficile MIC90 until Day 26 ± 1. Systemic exposure to fidaxomicin and OP-1118 was low throughout and there was no evidence of accumulation in plasma or stool during treatment.

The Gut Microbiome as a Therapeutic Target for Cognitive Impairment

Declining cognitive functions in older individuals have enormous emotional, clinical, and public health consequences. Thus, therapeutics for preserving function and keeping older adults living independently are imperative. Aging is associated dysbiosis, defined as a loss of number and diversity in gut microbiota, which has been linked with various aspects of cognitive functions. Therefore, the gut microbiome has the potential to be an important therapeutic target for symptoms of cognitive impairment. In this review, we summarize the current literature regarding the potential for gut-targeted therapeutic strategies for prevention/treatment of the symptoms of cognitive impairment. Specifically, we discuss four primary therapeutic strategies: wild-type and genetically modified probiotics, fecal microbiota transplantation, physical exercise, and high-fiber diets and specifically link these therapies to reducing inflammation. These strategies may hold promise as treatment paradigm symptoms related to cognitive impairment.

Spatial clusters of Clostridium difficile infection and an association with neighbourhood socio-economic disadvantage in the Australian Capital Territory, 2004-2014

BACKGROUND

In Australia, rates of Clostridium difficile infection (CDI) in all States and Territories have increased significantly since mid-2011, with rates of infection increasing faster in the community setting than within hospitals. Knowledge about the risk factors for CDI is essential to determine the risk of community outbreaks of CDI and to design interventions that reduce those risks.

METHODS

We examine the role of neighbourhood socio-economic disadvantage, demography and testing practices on spatial patterns in CDI incidence in the Australian Capital Territory (ACT). Data on all tests conducted for CDI, including postcode of residence, were obtained from January 2004-December 2014. Distribution of age groups and the neighbourhood Index of Relative Socio-economic Advantage Disadvantage (IRSAD) were obtained from the Australian Bureau of Statistics 2011 National Census data. A Bayesian spatial conditional autoregressive model was fitted at the postcode level to quantify the relationship between CDI and socio-demographic factors. To identify CDI hotspots, exceedance probabilities were set at a threshold of twice the estimated relative risk.

RESULTS

After controlling for spatial patterns in testing practices, area-level socio-economic advantage (IRSAD) (RR = 0.74, 95% CI 0.57, 0.94) was inversely associated with CDI. Three postcodes had a high probability (0.8-1.0) of excess risk of diagnosed CDI.

CONCLUSION

We demonstrate geographic variations in CDI in the ACT with a positive association of CDI with neighbourhood socioeconomic disadvantage and identify areas with a high probability of elevated risk compared with surrounding communities. These findings provide further evidence to inform a targeted response to reduce CDI risk.

Acute Clostridioides difficile Infection in Hospitalized Persons Aged 75 and Older: 30-Day Prognosis and Risk Factors for Mortality

OBJECTIVES

To assess the 30-day mortality predictive markers in the oldest patients with Clostridioides difficile infection (CDI) and to analyze the accuracy of the European severity risk markers in this population.

DESIGN

Observational prospective multicenter cohort study conducted by the French Infectious Diseases Society and Geriatrics Society networks. An electronic questionnaire was sent to members of both societies regarding their participation. Each investigator used an online survey to gather the data.

SETTING AND PARTICIPANTS

Patients aged ≥75 years hospitalized in French geriatric or infectious wards with confirmed diagnosis of CDI between March 1, 2016 and May 1, 2017.

METHODS

Clinical and laboratory parameters included medical history and comorbidities with the Cumulative Illness Rating Scale (CIRS). Criteria increasing the risk of severe disease were recorded as listed in the European guidelines. Therapeutic management, recurrence, and mortality rates were assessed at day 30 after diagnosis.

RESULTS

Included patients numbered 247; mean age was 87.2 years (SD 5.4). Most of the CDI incidences (66.4%) were health care-associated infections, with 81% diagnosed within 30 days of hospitalization; CIRS mean score was 16.6 (SD 6.6). Markers of severity ≥3 included 97 patients (39.3%). Metronidazole was the main initial treatment (51.0%). C difficile infection in the older adult was associated with a 30-day mortality of 12.6%. Multivariate analysis showed that baseline CIRS score [hazard ratio (HR) 1.06 per 1-point increase, 95% confidence interval (CI) 1.00-1.12] and evidence of cardiac, respiratory, or renal decompensation (HR 3.04, 95% CI 1.40-6.59) were significantly associated with mortality.

CONCLUSIONS AND IMPLICATIONS

European severity markers are adequate in the oldest old. Organ failure and comorbidities appeared to be the main markers of prognosis, and these should raise the awareness of practitioners. Although antibiotic treatment was not predictive of mortality, our results point out the lack of adherence to current guidelines in this population.

Antimicrobial susceptibility and molecular characterisation using whole-genome sequencing of Clostridioides difficile collected in 82 hospitals in Japan between 2014 and 2016

We studied the antimicrobial susceptibility and molecular characteristics, using draft whole-genome sequencing, of Clostridioides (Clostridium) difficile strains before and after treatment in adults with C. difficile infection (CDI) enrolled in a phase III, randomized, nationwide study of fidaxomicin versus vancomycin in Japan (ClinicalTrials.gov identifier NCT02179658). C. difficile strains were cultured from stool samples collected before and after standard treatment with either fidaxomicin or vancomycin.

We studied the antimicrobial susceptibility and molecular characteristics, using draft whole-genome sequencing, of Clostridioides (Clostridium) difficile strains before and after treatment in adults with C. difficile infection (CDI) enrolled in a phase III, randomized, nationwide study of fidaxomicin versus vancomycin in Japan (ClinicalTrials.gov identifier NCT02179658). C. difficile strains were cultured from stool samples collected before and after standard treatment with either fidaxomicin or vancomycin. Overall, 285 C. difficile strains were recovered, with 188 derived from CDI cases at baseline (87 patients received fidaxomicin, and 101 received vancomycin). No strains isolated from episodes of CDI at baseline were shown to have reduced susceptibilities to fidaxomicin (MIC, ≥1 mg/liter) or resistance to vancomycin and metronidazole. Thirty-three sequence types (STs) were identified, the most common being ST17 (n = 61 [32.4%]), ST8 (n = 26 [13.8%]), and ST2 (n = 21 [11.2%]). Core-genome single-nucleotide polymorphism analysis showed that outbreaks of C. difficile were unlikely to have occurred at each hospital. The predominant toxin gene profile was tcdA⁺ tcdB⁺ cdtA-cdtB⁻ (n = 149 [79.3%]). Six of 87 patients who received fidaxomicin harbored C. difficile isolates with reduced fidaxomicin susceptibilities conferred by previously described mutations, Val1143Leu/Gly/Asp in RpoB or Arg89Gly in RpoC or putative mutations, Gln1149Pro in RpoB, or Arg326Cys in RpoC. Allelic exchange studies of these putative mutations were not performed. Prior to fidaxomicin use, we found no C. difficile strains with reduced fidaxomicin susceptibility causing CDI in Japan; however, mutant strains with reduced fidaxomicin susceptibility were detected after fidaxomicin treatment.

Cost-Effectiveness Analysis of Bezlotoxumab Added to Standard of Care Versus Standard of Care Alone for the Prevention of Recurrent Clostridium difficile Infection in High-Risk Patients in Spain

Introduction

Clostridium difficile infection (CDI) is the major cause of infectious nosocomial diarrhoea and is associated with considerable morbidity, mortality and economic impact. Bezlotoxumab administered in combination with standard of care (SoC) antibiotic therapy prevents recurrent CDI. This study assessed the cost-effectiveness of bezlotoxumab added to SoC, compared to SoC alone, to prevent the recurrence of CDI in high-risk patients from the Spanish National Health System perspective.

Methods

A Markov model was used to simulate the natural history of CDI over a lifetime horizon in five populations of patients at high risk of CDI recurrence according to MODIFY trials: (1) ≥ 65 years old; (2) severe CDI; (3) immunocompromised; (4) ≥ 1 CDI episode in the previous 6 months; and (5) ≥ 65 years old and with ≥ 1 CDI episode in the previous 6 months. The incremental cost-effectiveness ratio (ICER) expressed as cost per quality-adjusted life-year (QALY) gained was calculated. Deterministic (DSA) and probabilistic sensitivity analyses (PSA) were performed.

Results

In all patient populations (from 1 to 5), bezlotoxumab added to SoC reduced CDI recurrence compared to SoC alone by 26.4, 19.5, 21.2, 26.6 and 39.7%, respectively. The resulting ICERs for the respective subgroups were €12,724, €17,495, €9545, €7386, and €4378. The model parameters with highest impact on the ICER were recurrence rate (first), mortality, and utility values. The probability that bezlotoxumab was cost-effective at a willingness-to-pay threshold of €21,000/QALY was 85.5%, 54.1%, 86.0%, 94.5%, 99.6%, respectively.

Conclusion

The results suggest that bezlotoxumab added to SoC compared to SoC alone is a cost-effective treatment to prevent the recurrence of CDI in high-risk patients. The influence of changes in model parameters on DSA results was higher in patients  ≥ 65 years old, with severe CDI and immunocompromised. Additionally, PSA estimated that the probability of cost-effectiveness exceeded 85% in most subgroups.

Funding

Merck Sharp & Dohme Corp.

Electronic supplementary material

The online version of this article (10.1007/s12325-018-0813-y) contains supplementary material, which is available to authorized users.

Frailty and the gut

Frailty, which is a syndrome that encompasses losses in physical, psychological and social domains, is responsible for enhanced vulnerability to endogenous and/or exogenous stressors. Frailty is a public health problem for an ageing society; however, it is poorly understood and often under-recognised in clinical settings. In particular, the impact of frailty on either intestinal functions, i.e. immune response, permeability, and absorption, or gut microbiota composition is as yet mostly unexplored. A better comprehension of the intestinal dysfunction occurring in the elderly would help in clarifying the mechanisms predisposing frail patients to a higher risk of infectious or inflammatory events. Moreover, recent evidence suggests that senescence-induced perturbations of the gut-brain axis are involved in the neuroinflammation process, thus raising the hypothesis that preserving gut permeability and preventing frailty-related changes in the microbiota composition might reduce the susceptibility to develop neurodegenerative disorders. In this review, we highlight the current insights concerning the relationship between frailty, intestinal functions, microbiota, and gut-brain axis.

A Novel Method to Mask the Bitter Taste of Berberine Hydrochloride: Powder Surface Modification

Background:

Berberine hydrochloride (BH) is widely used as a nonprescription drug to treat diarrhea without drug resistance and side effects worldwide. However, its drastic bitterness affects patient compliance severely. Hence, it is essential to mask the bitter taste of BH.

Objective:

Powder surface modification technology is attempted to mask the bitterness of BH through changing the surface properties in vibromill. The purpose of this study was to apply this technology to mask the bitterness of BH and improve the patient compliance.

Materials and Methods:

Initially, to prepare the modifier-BH composites, some parameters were optimized, including type of modifiers, ratio between BH and modifiers, and composite time. Then, the contact angles, scanning electron microscopy, and infrared (IR) spectroscopy were utilized to evaluate the microstructure of composites. Moreover, electronic tongue measurement, animal performance test, and bitterness evaluation methods were applied to evaluate the masking effect.

Results:

Based on the results of bitter taste evaluations, mannitol was chosen as the best modifier, and the optimal ratio of BH and mannitol was 6:4 with grinding together for 2 min in vibromill. For the composites prepared by this process, the IR spectroscopy and surface properties were similar with that of mannitol, and the microstructure was also demonstrated that small particles of mannitol successfully coated on the surface of BH. Special structure of the composites decreased the contact area between BH and external media and finally inhibited the bitterness. This effect was confirmed by three different kinds of methods.

Conclusion:

Our study provides a novel method to mask the bitter taste of drugs. It will be of great interest to pharmaceutical experts and pharmacists.

SUMMARY

Powder surface modification, a novel and different from previous technology, is used to prepare modifier-berberine hydrochloride composites to mask the bitter taste of BH

Electronic tongue measurement, animal performance test, human sensory test, and chemical evaluation method were simultaneously applied to evaluate the masking effect

A novel method to mask the bitter taste of drugs was provided.

Abbreviations used: BH:Berberine hydrochloride; CDI: Clostridium difficile infection; ODT: Orally disintegrating tablets; HPLC: High-performance liquid chromatography; CAs: Contact angles; SEM: Scanning electron microscopy; IR: Infrared spectrogram.

Clostridium difficile infection in hospitalized octogenarian patients

AIM

To evaluate the risk factors and outcome of Clostridium difficile infection in hospitalized octogenarian patients.

METHODS

A retrospective analysis of risk factors and outcome of C. difficile infection in hospitalized octogenarians was carried out at two academic centers in Romania from January 2014 to September 2016. Demographic, clinical and laboratory characteristics; antibiotics and proton pump inhibitors use in-hospital and 2 months before admission; comorbidities; length of hospital stay; treatment; and outcome were carefully collected from the patients' medical charts and compared with those from octogenarians hospitalized during the same period.

RESULTS

A total of 286 octogenarians were hospitalized during the study period and among them 79 (27.6%) were diagnosed with C. difficile infection. On multivariate logistic regression analyses, the previous 2 months' hospitalizations (OR 10.231, 95% CI 1.769-58.965, P = 0.009), antibiotic use 2 months before admission (OR 12.596, 95% CI 1.024-15.494, P = 0.048), antibiotic treatment during hospitalization (OR 6.302, 95% CI 3.510-11.316, P < 0.0001), arterial hypertension (OR 11.228, 95% CI 1.917-65.783, P = 0.007), chronic kidney disease (OR 4.474, 95% CI 1.037-19.299, P = 0.045) and chronic cardiac failure (OR 7.328, 95% CI 2.068-25.967, P = 0.002) were independently associated with infection. Patients with infection had longer length of hospital stay than those without (15.3 ± 5.1 vs 11.1 ± 4.3 days, P < 0.0001). None of the patients with infection had severe disease, none required surgery and none died during hospitalization.

CONCLUSIONS

Hospitalized octogenarians with comorbidities, recently hospitalized or receiving antibiotic treatment are at risk for C. difficile infection. Clinicians evaluating such patients should have a high index of suspicion for this infection. Geriatr Gerontol Int 2018; 18: 315-320.

Acid-Suppressive Therapy and Risk of Infections: Pros and Cons

This narrative review summarises the benefits, risks and appropriate use of acid-suppressing drugs (ASDs), proton pump inhibitors and histamine-2 receptor antagonists, advocating a rationale balanced and individualised approach aimed to minimise any serious adverse consequences. It focuses on current controversies on the potential of ASDs to contribute to infections-bacterial, parasitic, fungal, protozoan and viral, particularly in the elderly, comprehensively and critically discusses the growing body of observational literature linking ASD use to a variety of enteric, respiratory, skin and systemic infectious diseases and complications (Clostridium difficile diarrhoea, pneumonia, spontaneous bacterial peritonitis, septicaemia and other). The proposed pathogenic mechanisms of ASD-associated infections (related and unrelated to the inhibition of gastric acid secretion, alterations of the gut microbiome and immunity), and drug-drug interactions are also described. Both probiotics use and correcting vitamin D status may have a significant protective effect decreasing the incidence of ASD-associated infections, especially in the elderly. Despite the limitations of the existing data, the importance of individualised therapy and caution in long-term ASD use considering the balance of benefits and potential harms, factors that may predispose to and actions that may prevent/attenuate adverse effects is evident. A six-step practical algorithm for ASD therapy based on the best available evidence is presented.

Nutrition and the gut microbiome in the elderly

The gut microbiota is the assembly of microorganisms living in our intestine and their genomes are known as the microbiome. The correct composition and functionality of this microbiome is essential for maintaining a "healthy status." Aging is related to changes in the gut microbiota which are frequently associated with physiological modifications of the gastrointestinal tract, as well as, to changes in dietary patterns, together with a concomitant decline in cognitive and immune function, all together contributing to frailty. Therefore, nutritional strategies directed at restoring the microbiota in the elderly have to be addressed from a global perspective, considering not only the microbiota but also other extra-intestinal targets of action. The present review aims at summarizing the current knowledge on intestinal microbiota alterations and other functions impaired in the elderly and to analyze tools for implementing nutritional strategies, through the use of probiotics, prebiotics or specific nutrients in order to counterbalance such alterations.

Risk factors for Clostridium difficile infection in hemato-oncological patients: A case control study in 144 patients

Evidence on risk factors for Clostridium difficile infection (CDI) in hemato-oncologic patients is conflicting. We studied risk factors for CDI in a large, well-characterized cohort of hemato-oncological patients. 144 hemato-oncological patients were identified in this retrospective, single center study with a microbiologically confirmed CDI-associated diarrhea. Patients were compared with 144 age and sex matched hemato-oncologic patients with CDI negative diarrhea. Risk factors such as prior antimicrobial therapy, type of disease, chemotherapy and survival were evaluated. CDI-positive patients received more frequently any antimicrobial agent and antimicrobial combination therapy than CDI-negative patients (79% vs. 67%; OR = 2.26, p = 0.038 and OR = 2.62, p = 0.003, respectively). CDI positive patients were treated more frequently with antimicrobial agents active against C. difficile than CDI negative ones (25% vs. 13%; OR = 2.2, p = 0.039). The interval between last chemotherapy and onset of diarrhea was significantly shorter in patients without CDI (median, 17 days vs 36 days; p < 0.001). Our study demonstrates that chemotherapy is not a significant risk factor for CDI but for early onset CDI negative diarrhea. The predominant modifiable risk factor for CDI is in hemato-oncological patients antimicrobial treatment. These findings should be taken into account in the daily clinical practice to avoid CDI associated complications and excess health care costs.