Limited clinical utility of Clostridium difficile toxin testing in infants in a pediatric hospital

Diagnosis and management of paediatric Clostridioides difficile infection in a tertiary centre: A prospective audit

AIM

The optimisation of diagnosis and management of paediatric Clostridioides (formerly Clostridium) difficile (C. difficile) infection (CDI) has importance on multiple levels, from individual patient to population disease management and infection control. This study aimed to evaluate current practice at a paediatric tertiary hospital against Australasian Society for Infectious Diseases 2016 guidelines.

METHODS

Prospective audit was undertaken. All positive C. difficile tests (by two step immunoassay then polymerase chain reaction) over 6 month period were reviewed for appropriateness of testing, including review of clinical characteristics and treatment of appropriately requested positive tests (CDI cases). Consecutive test requests for C. difficile over 2 month period were reviewed for appropriateness of testing.

RESULTS

Of 70 consecutive test requests, 64 met laboratory criteria for processing. Of these, 31 (48%) out of 64 were asymptomatic or had clinically insignificant or laxative-associated diarrhoea. Overall, 44 (63%) out of 70 were deemed inappropriate requests. Of 45 positive tests, 17 (38%) were appropriately requested. Amongst inappropriate requests, 13 (46%) out of 28 were treated; those aged >2 years were significantly more likely to be treated (P < 0.05). Thirteen children were treated unnecessarily. Only one out of seven positive tests in infants (<1 year) was appropriately requested. Haematology/oncology patients accounted for 41% of cases. Treatment was in accordance with guidelines in 58% of cases.

CONCLUSIONS

Inappropriate testing for C. difficile and variable clinical response to positive tests have sequelae including unnecessary antibiotics for hospitalised children. Areas for improvement have been identified and this study confirms the need for establishment of national paediatric CDI guidelines with increased awareness of these by clinicians.

Risk Factors for Hospital-acquired Clostridium difficile Infection Among Pediatric Patients With Cancer

Hospital-acquired Clostridium difficile infection (CDI) may cause life-threatening colitis for children with cancer, making identification of risk factors important. We described characteristics of pediatric cancer patients with primary and recurring CDI, and evaluated potential risk factors. Among 189 cancer patients, 51 cases (27%) of CDI and 94 matched controls of cancer patients without CDI were analyzed. Multivariable logistic regression was used to evaluate the association between CDI and several potential risk factors. Median age of CDI cases was lower (3.3 y; 0.60 to 16.2) than controls (7.7 y; 0.4 to 20.5). Median duration of neutropenia before CDI was longer for CDI cases (10.0 d; 0.0 to 30.0) compared with duration calculated from reference date in controls (6.0 d; 0.0 to 29.0). Multivariable analysis showed that older age was associated with reduced risk (≥7 vs. 0 to 3 y, odds ratio=0.11; 95% confidence interval, 0.02-0.54), and prolonged neutropenia was associated with increased risk (odds ratio=1.11; 95% confidence interval, 1.01-1.22). CDI recurred in 26% of cases. Younger age and prolonged neutropenia were risk factors for CDI in children with cancer. Increasing awareness to these risk factors will help to identify opportunities for CDI prevention in cancer patients.

Current knowledge on the laboratory diagnosis of Clostridium difficile infection

Clostridium difficile (C. difficile) is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that is the principal etiologic agent of antibiotic-associated diarrhea. Infection with C. difficile (CDI) is characterized by diarrhea in clinical syndromes that vary from self-limited to mild or severe. Since its initial recognition as the causative agent of pseudomembranous colitis, C. difficile has spread around the world. CDI is one of the most common healthcare-associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients. Due to extensive antibiotic usage, the number of CDIs has increased. Diagnosis of CDI is often difficult and has a substantial impact on the management of patients with the disease, mainly with regards to antibiotic management. The diagnosis of CDI is primarily based on the clinical signs and symptoms and is only confirmed by laboratory testing. Despite the high burden of CDI and the increasing interest in the disease, episodes of CDI are often misdiagnosed. The reasons for misdiagnosis are the lack of clinical suspicion or the use of inappropriate tests. The proper diagnosis of CDI reduces transmission, prevents inadequate or unnecessary treatments, and assures best antibiotic treatment. We review the options for the laboratory diagnosis of CDI within the settings of the most accepted guidelines for CDI diagnosis, treatment, and prevention of CDI.

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.

Evaluating risk factors for Clostridium difficile infection in adult and pediatric hematopoietic cell transplant recipients

Background

Although hematopoietic cell transplant (HCT) recipients are routinely exposed to classic risk factors for Clostridium difficile infection (CDI), few studies have assessed CDI risk in these high-risk patients, and data are especially lacking for pediatric HCT recipients. We aimed to determine incidence and risk factors for CDI in adult and pediatric allogeneic HCT recipients.

Methods

CDI was defined as having diarrhea that tested positive for C. difficile via PCR, cytotoxin assay, or dual enzyme immunoassays. We included all patients who received an allogeneic HCT from 2008 to 2012 at the Fred Hutchinson Cancer Research Center; those <1 year old or with CDI within 8 weeks pre-HCT were excluded. Patients were categorized by transplanting hospital (“adult” or “pediatric”) and followed for 100 days post-HCT.

Results

Of 1182 HCT recipients, CDI was diagnosed in 17 % (33/192) of pediatric recipients for an incidence of 20 per 10,000 patient-days, and 11 % (107/990) of adult recipients for an incidence of 12 per 10,000. Pediatric recipients were diagnosed a median of 51 days (interquartile range [IQR]: 5, 72) after HCT and adults at 16 days (IQR = 5, 49). Compared with calendar year 2008, pediatric recipients transplanted in 2012 were at increased risk for CDI (hazard ratio [HR] = 3.99, p =.02). Myeloablative conditioning increased CDI risk in adult recipients (HR = 1.81, p =.005).

Conclusions

Pediatric and adult allogeneic recipients are at high risk of CDI post-HCT, particularly adult recipients of myeloablative conditioning. Differences in CDI incidence between children and adults may have resulted from exposure differences related to age; therefore, separately evaluating these groups should be considered in future CDI studies.

Pitfalls in Diagnosis of Pediatric Clostridium difficile Infection

The incidence of Clostridium difficile infection (CDI) has risen among children and C difficile is increasingly recognized as an important cause of healthcare-associated diarrhea among pediatric patients. Still, increased identification of CDI in healthy children in the community and increased testing among infants requires cautious interpretation, given the high prevalence of asymptomatic colonization in young infants and frequent detection of viruses and other co-pathogens in stool specimens in these age groups. The significance of CDI among infants and the implications of positive C difficile testing among healthy children in the community are areas in need of further study.

Severe clinical outcome is uncommon in Clostridium difficile infection in children: a retrospective cohort study

Background

Clostridium difficile infection (CDI) is the most common cause of health care–associated diarrhea in children and adults. Although serious complications of CDI have been reported to be increasing in adults, this trend has not yet been demonstrated in children. The purpose of this study was to examine the features of CDI in a pediatric population, with special attention to the occurrence of CDI-related severe outcomes.

Methods

A chart review was conducted for patients with C. difficile infection detected by cytotoxin assay between August, 2008 and July, 2012. Basic demographics, mode of acquisition (nosocomial versus community), laboratory and clinical features, treatment, and outcome data were collected. Pulsed-field gel electrophoresis and polymerase chain reaction detection of toxin A (tcdA), toxin B (tcdB), binary toxin (cdtB) and tcdC genes were performed on isolates from nosocomial cases by the National Microbiology Laboratory, Winnipeg, Manitoba.

Results

Ninety percent of children with CDI experienced resolution of symptoms by 30 days after disease onset and 2% experienced a severe outcome. There were no cases where colectomy was performed for CDI, and only one case where CDI contributed to death. Various combinations of clinical and laboratory features were not predictive of a severe outcome. Seventy-four percent of cases were nosocomial-associated. Among all cultured strains, the NAP4 strain occurred most frequently (24%), followed by NAP1 (11%). There was no association between strain type and clinical outcome; however, relapses were significantly more frequent in NAP4-infected children.

Conclusions

Severe outcomes due to CDI are uncommon in children compared to adults. Further prospective pediatric studies on CDI in community and hospital settings are required to better understand risk factors, optimal treatment and the significance of NAP4 in pediatric CDI.

Trends in Clostridium difficile infection and risk factors for hospital acquisition of Clostridium difficile among children with cancer

OBJECTIVES

To study the trend of Clostridium difficile infection (CDI) and risk factors for hospital acquired CDI (HA-CDI) among children with cancer.

STUDY DESIGN

We analyzed 33 095 first pediatric hospitalizations for malignancy among 43 pediatric hospitals between 1999 and 2011. The effect of demographics, disease characteristics, and weekly drug exposure (antibiotics, antacids, and chemotherapy) on HA-CDI was assessed with multivariate Cox regression. CDI was defined by the combination of International Classification of Diseases, 9th edition-Clinical Modification (ICD-9CM), CDI diagnostic assay billing code, and concurrent administration of a CDI-active antibiotic. HA-CDI was defined as CDI with assay occurring after the sixth hospital day.

RESULTS

A total of 1736 admissions with CDI were identified, of which 380 were HA-CDI. CDI incidence increased from 1999-2006 (P = .01); however, CDI testing frequency and disease decreased from 2006-2010 (P < .05). Admissions with HA-CDI had longer lengths of stay compared with those without HA-CDI (35 days vs 12 days, P < .01) and greater risk of inpatient mortality (relative risk 2.3, P < .01). Increased risk of HA-CDI (hazard ratio [95% CI]) was seen after exposure to the following drugs: aminoglycoside (1.357 [1.053-1.749]), third generation cephalosporin (1.518 [1.177-1.959]), cefepime (2.383 [1.839-3.089]), and proton pump inhibiting agent (1.398 [1.096-1.784]) in the prior week, and chemotherapy (1.942 [1.491-2.529]) in the 8-14 days prior to HA-CDI onset. Histamine-2 receptor antagonist exposure in the prior week was associated with decreased risk of HA-CDI (0.730 [0.584-0.912]).

CONCLUSIONS

Despite an apparent decrease in CDI incidence from 2006-2010, HA-CDI remains prevalent and morbid among children with cancer. Recent exposure to chemotherapy, proton pump inhibitor, and certain antibiotics were independent risk factors for HA-CDI.

Asymptomatic colonization by Clostridium difficile in infants: implications for disease in later life

Approximately 60% to 70% of healthy newborns and infants are colonized by the enteric pathogen Clostridium difficile. For reasons that remain obscure, these colonized infants show no ill effects from the potent exotoxins released by this anaerobe, in contrast to older children and adults who are susceptible to severe diarrhea and colitis. The organism is acquired in infancy, as in adults, from environmental contamination in the nursery or home environment. Between 12 and 24 months C difficile is evicted as a commensal, presumably by the gradual development of the adult colonic microflora. The carrier state is well tolerated by infants, and the immunoglobulin G antitoxin response that develops during the carrier state appears to provide durable protection against subsequent C difficile disease.