Clinical significance of Clostridium difficile and its toxins in faeces of immunocompromised children

Pathogens causing diarrhoea among Bangladeshi children with malignancy: Results from two pilot studies

BACKGROUND

Diarrhoea is a frequent symptom in children with cancer, and occurs due to a composite effect of underlying disease and immunosuppression consequent to therapy, malnutrition, and non-infective aetiologies such as mucositis. In a large proportion of cases, the aetiology of diarrhoea remains unknown but is often attributed to multiple pathogens including parasites.

AIM

To identify and describe the pathogens causing diarrhoea in Bangladeshi children with cancer.

METHODS

Two cross-sectional pilot studies were conducted involving paediatric oncology patients with diarrhoea. Stool samples were collected from children who were hospitalised with or without being treated with chemotherapy during the study period, and had diarrhoea at any stage during their admission. In the first study, stool samples were tested by conventional microbiological methods and by polymerase chain reaction for parasites, and by immunoassays for Clostridium difficile. In the second study, conventional microbiology was conducted for bacteria and parasites including an enzyme-linked immunosorbent assay for Cryptosporidium antigen, and in a subset, immunoassays for Clostridium difficile.

RESULTS

In the first study Giardia lamblia was detected in 68.5% of samples, Entamoeba histolytica in 13%, Cryptosporidium in 5.6%, non-toxigenic C. difficile in 22.4%, and other bacteria in 5.2%. In the second study, E. histolytica was detected in 10% of samples, Cryptosporidium in 4.3%, G. lamblia in 1.4%, C. difficile in 5.1%, and other bacteria in 5.7% of samples.

CONCLUSION

These pilot data suggest that parasites are important aetiologies of diarrhoea in Bangladeshi children with malignancy. While molecular diagnostic tools detect an array of stool pathogens with greater sensitivity, conventional diagnostic methods are also useful.

Clostridium difficile causing pediatric infections: New findings from a hospital-based study in Italy

Recent studies support a change of Clostridium difficile infections (CDIs) epidemiology in pediatric patients. Since limited information is available about C. difficile in this population, we investigated the epidemiology of CDI in a large pediatric hospital that acts as reference centre in Italy and analyzed C. difficile isolates to identify the prevalent PCR-ribotypes (RTs), the binary toxin (CDT)-positive strains and the antibiotic susceptibility patterns. The CDI incidence was 6.6 cases/1000 admissions and the majority (92%) of CDI were healthcare-associated (47% occurred in the Hematology-Oncology and in the Gastroenterology units). Most of symptomatic children <3 years with a positive culture for C. difficile were negative for other gastrointestinal pathogens, supporting C. difficile as cause of disease in these patients, including those showing recurrences. Strains RT020 (16%) and RT014 (14%) were identified as the main cause of infection, while RT356/607 and RT018, predominant in Italian adult patients, were absent (RT356/607) or rarely found (RT018) among children. CDT-positive strains represented the 20% of the total number of isolates analyzed. In particular, two emerging types, RT033 and RT442, were recognized as Toxin A-/Toxin B-/CDT+. Resistance to antibiotics characterized almost 50% of the toxigenic isolates analyzed in this study and, in particular, 20% of them were multidrug resistant (MDR). The emergence and circulation of strains with peculiar toxins profiles and/or MDR strongly highlight the necessity of a rapid CDI diagnosis, a careful monitoring of C. difficile in pediatric patients and a more strict control of antibiotics usage in the Italian pediatric hospitals.

The role of Clostridium difficile in the paediatric and neonatal gut - a narrative review

Clostridium difficile is an important nosocomial pathogen in adults. Its significance in children is less well defined, but cases of C. difficile infection (CDI) appear to be increasingly prevalent in paediatric patients. This review aims to summarize reported Clostridium difficile carriage rates across children of different age groups, appraise the relationship between CDI and factors such as method of delivery, type of infant feed, antibiotic use, and co-morbidities, and review factors affecting the gut microbiome in children and the host immune response to C. difficile. Searches of PubMed and Google Scholar using the terms 'Clostridium difficile neonates' and 'Clostridium difficile children' were completed, and reference lists of retrieved publications screened for further papers. In total, 88 papers containing relevant data were included. There was large inter-study variation in reported C. difficile carriage rates. There was an association between CDI and recent antibiotic use, and co-morbidities such as immunosuppression and inflammatory bowel disease. C. difficile was also found in stools of children with diarrhoea attributed to other pathogens (e.g. rotavirus). The role of C. difficile in the paediatric gut remains unclear; is it an innocent bystander in diarrhoeal disease caused by other organisms, or a pathogen causing subclinical to severe symptoms? Further investigation of the development of serological and local host response to C. difficile carriage may shed new light on disease mechanisms. Work is underway on defining a framework for diagnosis and management of paediatric CDI.

Clostridium difficile in paediatric populations

An increase in Clostridium difficile infection incidence has been observed among hospitalized children in the United States. The present statement, targeted at clinicians caring for infants and children in community and institutional settings, summarizes the relevant information relating to the role of C difficile in childhood diarrhea and provides recommendations for diagnosis, prevention and treatment. Significant differences between adult and paediatric risk factors and disease are discussed, along with emerging therapies. The relationship between age and disease severity in children with a newly emergent and more fluoroqinolone-resistant strain of C difficile (North American Pulse-field type-1 [NAP1]) remains unknown. The importance of antimicrobial stewardship as a preventive strategy is highlighted. This statement replaces a previous Canadian Paediatric Society position statement on C difficile published in 2000.

Clostridium difficile infection in children: a comprehensive review

OBJECTIVE

To provide a comprehensive review of the literature relating to Clostridium difficile (C. difficile) infection (CDI) in the pediatric population.

METHODS

Two investigators conducted independent searches of PubMed, Web of Science, and Scopus until March 31st, 2013. All databases were searched using the terms 'Clostridium difficile infection', 'Clostridium difficile associated diarrhea' 'antibiotic associated diarrhea', 'C. difficile', in combination with 'pediatric' and 'paediatric'. Articles which discussed pediatric CDI were reviewed and relevant cross references also read and evaluated for inclusion. Selection bias could be a possible limitation of this approach.

FINDINGS

There is strong evidence for an increased incidence of pediatric CDI. Increasingly, the infection is being acquired from the community, often without a preceding history of antibiotic use. The severity of the disease has remained unchanged. Several medical conditions may be associated with the development of pediatric CDI. Infection prevention and control with antimicrobial stewardship are of paramount importance. It is important to consider the age of the child while testing for CDI. Traditional therapy with metronidazole or vancomycin remains the mainstay of treatment. Newer antibiotics such as fidaxomicin appear promising especially for the treatment of recurrent infection. Conservative surgical options may be a life-saving measure in severe or fulminant cases.

CONCLUSIONS

Pediatric providers should be cognizant of the increased incidence of CDI in children. Early and judicious testing coupled with the timely institution of therapy will help to secure better outcomes for this disease.

Five years experience of Clostridium difficile infection in children at a UK tertiary hospital: proposed criteria for diagnosis and management

Background

Clostridium difficile infection (CDI) is associated with significant morbidity and mortality in adults. There is increasing evidence of the pathogenic role of C. difficile in the paediatric population. We sought to ascertain the clinical presentation and severity of CDI in children at our institution and develop criteria to aid management.

Methods

Clinical data was retrospectively collected from all children (0–16 yrs) with a positive C. difficile toxin result over a 5-year period. National adult guidelines were used to assess the severity and management of CDI.

Results

Seventy-five patients were included with a mean age of 2.97 years. Forty-nine were hospital onset, 22 community onset and 4 healthcare-associated. The most common co-morbidity among the hospital onset infections was malignancy. Gastrointestinal conditions were most common among community onset infections. Fifty-five cases (73.3%) had received antibiotics in the preceding month, 7 (9.3%) had cow’s milk intolerance and 9 (12%) had co-infection with another gut pathogen. According to national adult guidelines 57 cases (76%) were categorised as severe. Thirty cases received oral metronidazole, two patients required intensive care and one patient had a sub-total colectomy for pseudomembranous colitis. No mortality was observed.

Discussion

We confirm the association of paediatric CDI with co-morbidities such as haematological and solid organ malignancies, recent antibiotic use and hospitalisation. We observed an association between cows milk protein intolerance and C. difficile. The use of adult criteria overestimated severity of disease in this cohort, as most cases experienced a mild course of illness with low morbidity and no mortality. This indicates that adult scoring criteria are not useful in guiding management and we propose specific criteria for children.

Clostridium difficile: an emerging pathogen in children

Clostridium difficile is emerging as an important enteric pathogen in children. Historically considered as an asymptomatic colonizer of the gastrointestinal tract, C. difficile infection (CDI) has not been well-studied in pediatric populations. While asymptomatic carriage remains high among infants, recent epidemiological surveillance has demonstrated a rise in the prevalence of CDI in both healthcare and community settings, particularly in children 1-5 years of age. The pathogenesis of pediatric CDI, including the factors underlying the absence of toxin-mediated effects among colonized infants, remains ill-defined. Studies suggest that traditional adult CDI risk factors such as antibiotic and healthcare exposure may not be as important for children who acquire CDI in the community. As recognition of the significant impact of CDI in children increases, the pressing need for deepening our understanding of this disease and identifying optimal therapeutic and preventative strategies is becoming apparent.

Clostridium difficile in children: colonisation and disease

Clostridium difficile is the commonest cause of hospital acquired diarrhoea in adults and is associated with significant mortality and morbidity. The clinical significance of C. difficile in children, however, is less certain. In this article we discuss colonisation and infection and describe C. difficile in childhood in terms of risk factors, epidemiology and management.

Severe Clostridium difficile-associated disease in children

Three cases of Clostridium difficile-associated disease in children were detected within a short time interval. Intensive therapy was required in 2 cases with colectomy in one of them. One of the severe cases was community-acquired. Two patients had underlying diseases (Hirschprung disease, Down syndrome) and also tested positive for enteric viruses (rotavirus, calicivirus).

Surveillance for nosocomial and central line-related infections among pediatric hematology-oncology patients

OBJECTIVE

To determine the incidence of all nosocomial infections (NIs) in pediatric hematology-oncology patients, as well as central venous access device (CVAD)-associated infections acquired during home care.

DESIGN

Prospective surveillance study.

SETTING

The Pediatric Hematology and Oncology Department at the University Hospital Bonn.

PATIENTS

All patients admitted from January through October 1998 (surveillance period).

METHODS

Standardized surveillance system based on the Centers for Disease Control and Prevention's National Nosocomial Infections Surveillance System.

RESULTS

A total of 143 patients were hospitalized for 3,701 days (776 admissions) during the surveillance period. Of the 40 NIs detected, 26 were CVAD-related, with 21 bloodstream infections (BSIs) and 5 local infections. Four were Clostridium difficile-associated diarrheal illnesses, 3 were pneumonias, and 7 were other infections. The incidence of NIs was 10.8 per 1,000 patient-days (5.2 NIs/100 admissions). The overall CVAD-related BSI rate was 7.4 per 1,000 utilization days, without a significant difference between implanted infusion ports and tunneled catheters. In addition, 7 CVAD-related infections occurred during home care. All 8 BSIs associated with tunneled catheters and 13 (76%) of the 17 BSIs associated with ports were acquired nosocomially. For inpatients and outpatients combined, the exit sites of tunneled catheters were more likely to become locally infected than were the needle entry sites of ports (relative risk, 8.0; P=.007). In 30 (75%) of the 40 NIs, the affected patients had severe neutropenia (<500/mm3) at the time of infection.

CONCLUSIONS

Most NIs in the pediatric hematology-oncology patients were associated with CVAD devices. Although many infections in this high-risk population may not be preventable through infection control measures, the careful evaluation of specific infection rates permits the identification of risk factors that may be targeted by infection control programs. Prospective surveillance for NIs on pediatric oncology units is an indispensable tool for this internal quality control.

Antibiotic-associated diarrhoea, Clostridium difficile, and short-chain fatty acids

BACKGROUND

It has been hypothesized that Clostridium difficile and decreased colonic production of short-chain fatty acids (SCFAs) cause the development of antibiotic-associated diarrhoea. We therefore wanted to investigate the effects of an intensive and uniform antibiotic therapy on faecal SCFAs concentrations. C. difficile, and extent of diarrhoea.

METHODS

Fifteen liver-transplanted patients who received oral bowel flora suppression therapy (6.3 g cefuroxime, 0.6 g tobramycin, and 0.5 g nystatin three times daily) were studied for 12 days before and 12 days after discontinuation of therapy.

RESULTS

Thirteen of the 15 patients (87%) developed diarrhoea. Colonic fermentation was negligible in all patients, judged by very low levels of faecal SCFAs (< 10 mmol/l). Diarrhoea lessened as suppression therapy proceeded despite continuous low levels of SCFAs. Initial stool frequency of 4.1 +/- 0.6 and viscosity of 2.5 +/- 0.2 per day (on a scale of 1-3; mean +/- SE) decreased to 2.2 +/- 0.5 (p = 0.0009) and 1.6 +/- 0.2 (p = 0.003) per day, respectively, just before cessation of suppression therapy. Both SCFAs and stool habits normalized within days after discontinuation of antibiotics. Only a few samples from 2 patients were culture-positive for C. difficile during therapy, whereas 9 of the 15 patients (60%) became culture-positive (6 cytotoxin-positive) after cessation of suppression therapy at a time when none had diarrhoea.

CONCLUSIONS

Intensive treatment with antibiotics directed against the colonic flora resulted in diarrhoea in the vast majority of patients, but the diarrhoea was self-limiting despite continual antibiotic treatment and very low faecal concentrations of SCFAs. C. difficile was not associated with antibiotic-associated diarrhoea but was a common finding after treatment with antibiotics was stopped at the time when diarrhoea had ceased.

Clostridium difficile infection

The spore-forming anaerobe Clostridium difficile has become a serious enteropathogen. Changes in the composition of natural intestinal flora, mainly due to antibiotic therapy, permit its colonization of, and multiplication in, the colon. The disease is caused by (entero)toxin A and (cyto)toxin B, and infection ranges from asymptomatic carrier state and mild diarrhea to pseudomembranous colitis. The clinical diagnosis is made by observing inflammatory, sometimes bloody, diarrhea and by the colonoscopic detection of epithelial necrosis, ulceration, and, in the advanced state, pseudomembrane formation. The laboratory supports the diagnosis by detecting toxin A and/or B by an enzyme-linked immunoassay with high specificity, but sometimes less sensitivity than with the cytotoxin assay in tissue culture cells. Fecal leukocytes or fecal lactoferrin may be found. Culture for the isolation and identification of toxigenic C. difficile is time consuming but necessary for epidemiological studies. Polymerase chain reaction (PCR) tests have been tested for detection of the toxin B gene directly in stool. Therapy consists of stopping all systemic antibiotic treatment and the use of oral metronidazole or vancomycin. There may be more relapses after vancomycin therapy, and the increasing vancomycin resistance of Enterococcus is worrisome. Prevention, especially of nosocomial spread, requires isolation and enforced handwashing. For epidemiological studies, the bacteria can be typed by molecular DNA analyses, including PCR, protein electrophoresis, and immunological tests.