Clostridium difficile infection in pediatric acute myeloid leukemia: from the Canadian Infections in Acute Myeloid Leukemia Research Group

Guideline for the management of Clostridioides difficile infection in pediatric patients with cancer and hematopoietic cell transplantation recipients: 2024 update

Our objective was to update a clinical practice guideline for the prevention and treatment of Clostridioides difficile infection (CDI) in pediatric patients with cancer and hematopoietic cell transplantation recipients. We reconvened an international multi-disciplinary panel. A systematic review of randomized controlled trials (RCTs) for the prevention or treatment of CDI in any population was updated and identified 31 new RCTs. Strong recommendations were made to use either oral metronidazole or oral vancomycin for non-severe CDI treatment, and to use either oral vancomycin or oral fidaxomicin for severe CDI. A strong recommendation that fecal microbiota transplantation should not be routinely used to treat CDI was also made. The panel made two new good practice statements to follow infection control practices including isolation in patients experiencing CDI, and to minimize systemic antibacterial administration where feasible, especially in patients who have experienced CDI.

Evaluation of the prevalence of Aeromonas spp., Campylobacter spp., and Clostridioides difficile in immunocompromised children with diarrhea

AIM

Diarrhea is a common disease in immunocompromised patients and can be associated with greater morbidity and even mortality. Therefore, the present study was designed to determine the prevalence of Aeromonas spp., Campylobacter spp., and C. difficile among immunocompromised children.

METHODS

This study was conducted on 130 stool samples from patients with diarrhea who had defects in the immune system and were referred to Hazrat Masoumeh Children's Hospital in Qom. Demographic information, clinical symptoms, immune status, and duration of chemotherapy were also recorded for each child. DNAs were extracted from the stool, and then direct PCR assays were done by specific primers for the detection of Aeromonas spp., Campylobacter spp., and toxigenic C. difficile, including tcdA/B and cdtA/B genes. Co-infection in patients was also evaluated.

RESULTS

60.8% and 39.2% were male and female, respectively, with a m ± SD age of 56.72 ± 40.49 months. Most cases of immunocompromised states were related to Acute Lymphocytic Leukemia (77.7%) and Non-Hodgkin Lymphoma (14.6%). 93.1% of patients were undergoing chemotherapy during the study. Among patients, most clinical symptoms were related to bloody diarrhea (98.5%) and fever (92.3%). Based on PCR, 14.6, 9.2, and 1.5% were positive for Aeromonas spp., C. difficile, and C. jejuni, respectively. Among the C. difficile-positive cases, the tcdA gene was only detected in one patient. In total, three co-infections were identified, which included Aeromonas spp./C. difficile (tcdA+), C. jejuni/C. difficile, and C. jejuni/Aeromonas spp.

CONCLUSIONS

This is the first study in Iran to investigate the simultaneous prevalence of some pathogens in immunocompromised children with diarrhea. Because Aeromonas spp., Campylobacter spp., and C. difficile are not routinely detected in some laboratories, infections caused by them are underappreciated in the clinic. Our results showed that these pathogens are present in our region and can cause gastroenteritis in children, especially those with underlying diseases. Therefore, increasing the level of hygiene in some areas and controlling bacterial diarrheal diseases should be given more attention by health officials.

Double-Blind, Placebo-Controlled Study of Bezlotoxumab in Children Receiving Antibacterial Treatment for Clostridioides difficile Infection (MODIFY III)

BACKGROUND

Therapies to prevent recurrence of Clostridioides difficile infection (CDI) in pediatric patients are needed. Bezlotoxumab is a fully human monoclonal antibody approved for prevention of recurrent CDI in adults. We assessed the pharmacokinetics, safety, tolerability, and efficacy of bezlotoxumab in pediatric patients.

METHODS

MODIFY III was a multicenter, double-blind, placebo-controlled study of bezlotoxumab in children (1 to <18 years) receiving antibacterial treatment for CDI. Participants were randomized 3:1 to receive a single infusion of bezlotoxumab (10 mg/kg) or placebo and were stratified by age at randomization (cohort 1: 12 to <18 years, cohort 2: 1 to <12 years). The primary objective was to characterize bezlotoxumab pharmacokinetics to support dose selection for pediatric patients; the primary endpoint was the area under the bezlotoxumab serum concentration-time curve (AUC0-inf). Safety, tolerability, and efficacy were monitored for 12 weeks post-infusion.

RESULTS

A total of 148 participants were randomized and 143 were treated: 107 with bezlotoxumab and 36 with placebo (cohort 1 n = 60, cohort 2 n = 83; median age 9.0 years); 52.4% of participants were male and 80.4% were white. Geometric mean ratios (90% CI) for bezlotoxumab AUC0-inf were 1.06 (0.95, 1.18) and 0.82 (0.75, 0.89) h * μg/mL for cohorts 1 and 2, respectively. Bezlotoxumab 10 mg/kg was generally well-tolerated with an adverse event profile similar to placebo, including no treatment discontinuations due to adverse events. CDI recurrence was low and comparable for bezlotoxumab (11.2%) and placebo (14.7%).

CONCLUSIONS

The results of this study support the bezlotoxumab dose of 10 mg/kg for pediatric patients.

TRIAL REGISTRATION

NCT03182907 at ClinicalTrials.gov.

Abdominal Complications During Treatment for Pediatric Acute Myeloid Leukemia

Acute myeloid leukemia (AML) accounts for 15% to 20% of childhood leukemias. Because of high-intensive therapy, up to 5% of patients suffer from treatment-related mortality (TRM). Abdominal complications are frequent, however, literature on this subject is sparse. We aimed to characterize severe abdominal pain (AP) and hyperbilirubinemia experienced by pediatric AML patients treated according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO)-AML 2004 protocol (n=313). Patients were censored at hematopoietic stem cell transplantation and relapse. Toxicity information was collected prospectively. Additional information was requested retrospectively from the treating centers. Sixteen episodes of hyperbilirubinemia and 107 episodes of AP were reported. The treating centers deemed infection (30%) and typhlitis (18%) as the most frequent causes of AP. Six patients developed appendicitis (2%). Patients experiencing concurrent AP and sepsis had a high risk of TRM (36%, n=4). Eighty percent of episodes with hyperbilirubinemia fulfilled the European Society for Bone and Marrow Transplantation criteria for sinusoidal obstruction syndrome. In conclusion, abdominal complications were frequent with infection considered the predominate cause. Most patients with hyperbilirubinemia fulfilled the criteria for sinusoidal obstruction syndrome. AML treatment might be associated with appendicitis. Patients suffering from concurrent AP and sepsis had a high risk of TRM indicating that high awareness of abdominal complications is essential to reduce mortality, especially during sepsis.

Pharmacological Management of Pediatric Clostridioides difficile Infection: Clarifying the Controversies

Clostridioides difficile infection (CDI) is a major public health concern for pediatric and adult patients. The management of pediatric CDI poses a challenge to healthcare providers due to lack of strong randomized controlled trials to guide pharmacological management. Additionally, recent updates to CDI guidelines recommend oral vancomycin over metronidazole for the management of CDI in adults, leaving questions regarding how to best manage pediatric patients. This continuing education pharmacotherapy review describes available evidence for the safety and efficacy of medications used in the treatment and management of pediatric CDI and aims to clarify discrepancies between pediatric and adult recommendations.

Epidemiology, Diagnosis, and Treatment of Clostridioides difficile Infection in Immunocompromised Children

Clostridioides difficile infection is very common in immunocompromised children. Management is confounded by frequent asymptomatic colonization, multiple alternative etiologies for gastrointestinal symptoms, and high rates of relapse. Important considerations include indications for testing, appropriate choice of diagnostic tests, antibiotic therapy for initial and subsequent episodes, and primary and secondary prevention.

Clostridioides difficile Infections in Inpatient Pediatric Oncology Patients: A Cohort Study Evaluating Risk Factors and Associated Outcomes

BACKGROUND

Clostridioides difficile infection (CDI) is a significant source of morbidity in pediatric cancer patients. Few reports to date have evaluated risk factors and short-term outcomes for this population.

METHODS

We retrospectively evaluated pediatric oncology admissions at St Louis Children's Hospital from 2009 to 2018. All inpatient cases of diagnosed initial CDI were identified. We aimed to investigate the prevalence of CDI and associated risk factors, including coadmission with another patient with CDI, and to evaluate short-term outcomes including length of stay and delays in subsequent scheduled chemotherapy.

RESULTS

Review of 6567 admissions from 952 patients revealed 109 CDI cases (11.4% of patients). Patients with leukemia or lymphoma, compared to those with solid tumors, were more likely to have CDI (odds ratio [OR], 3 [95% CI, 1.4-6.6], and 3 [95% CI, 1.3-6.8], respectively). Autologous hematopoietic stem cell transplant (HSCT) was also a risk factor (OR, 3.5 [95% CI, 1.7-7.4]). Prior antibiotic exposure independently increased the risk for CDI (OR, 3.0 [95% CI, 1.8-4.8]). Concurrent admission with another patient with CDI also significantly increased the risk (OR, 84.7 [95% CI, 10.5-681.8]). In contrast to previous reports, exposure to acid-suppressing medications decreased the risk for CDI (OR, 0.5 [95% CI, .3-.7]). CDI was associated with increased length of stay (mean difference, 8 days [95% CI, 4.6-11.4]) and prolonged delays for subsequent chemotherapy (mean difference, 1.4 days [95% CI, .1-2.7]).

CONCLUSIONS

CDI in pediatric oncology patients significantly prolongs hospitalization and delays chemotherapy treatment plans. Interventions to control CDI will improve the care of pediatric oncology patients.

Associations between pretherapeutic body mass index, outcome, and cytogenetic abnormalities in pediatric acute myeloid leukemia

Background

Associations between body mass index (BMI), outcome, and leukemia‐related factors in children with acute myeloid leukemia (AML) remain unclear. We investigated associations between pretherapeutic BMI, cytogenetic abnormalities, and outcome in a large multinational cohort of children with AML.

Methods

We included patients, age 2‐17 years, diagnosed with de novo AML from the five Nordic countries (2004‐2016), Hong Kong (2007‐2016), the Netherlands and Belgium (2010‐2016), and Canada and USA (1995‐2012). BMI standard deviations score for age and sex was calculated and categorized according to the World Health Organization. Cumulative incidence functions, Kaplan‐Meier estimator, Cox regression, and logistic regression were used to investigate associations.

Results

In total, 867 patients were included. The median age was 10 years (range 2‐17 years). At diagnosis, 32 (4%) were underweight, 632 (73%) were healthy weight, 127 (15%) were overweight, and 76 (9%) were obese. There was no difference in relapse risk, treatment‐related mortality or overall mortality across BMI groups. The frequency of t(8;21) and inv(16) increased with increasing BMI. For obese patients, the sex, age, and country adjusted odds ratio of having t(8;21) or inv(16) were 1.9 (95% confidence interval (CI) 1.1‐3.4) and 2.8 (95% CI 1.3‐5.8), respectively, compared to healthy weight patients.

Conclusions

This study did not confirm previous reports of associations between overweight and increased treatment‐related or overall mortality in children. Obesity was associated with a higher frequency of t(8;21) and inv(16). AML cytogenetics appear to differ by BMI status.

Intensity of Therapy for Malignancy and Risk for Recurrent and Complicated Clostridium difficile Infection in Children

Clostridium difficile infection (CDI) is common in pediatric oncology patients and is often associated with recurrences and complications. We hypothesized that higher intensity of chemotherapy would be associated with these outcomes. We conducted a retrospective cohort study including all cases of primary CDI in children with malignancy in our institution for over 7 years. Intensity of chemotherapy was measured by the Intensity of Treatment Rating Scale, third edition, ranging from level 1 (minimal) to 4 (highest). Outcomes included recurrence within both 56 and 180 days, CDI-associated complications, and primary treatment failure (PTF). Risk of recurrence was compared using Cox proportional hazards regression. Among 192 patients with CDI and malignancy, 122 met inclusion criteria. CDI recurred in 27% (31/115) of patients followed for 56 days and 46% (48/104) of patients followed for 180 days. Fourteen patients (11.4%) had a CDI-associated complication, including 4 intensive care unit admissions and 3 surgical procedures, but no deaths. Ten patients (8.2%) had PTF. Although PTF and severe complications were infrequent, recurrence was common in our cohort. None of these outcomes were associated with level of treatment intensity. More research is required to assess oncologic and nononcologic risk factors for CDI recurrence, PTF, and severe CDI-associated complications.

Risk factors for Clostridium difficile infection in pediatric inpatients: A meta-analysis and systematic review

Objective:

To summarize risk factors for Clostridioides (formerly Clostridium) difficile infection (CDI) in hospitalized pediatric patients as determined by previous observational studies.

Design:

Meta-analysis and systematic review.

Patients:

Studies evaluating risk factors for CDI in pediatric inpatients were eligible for inclusion.

Method:

We systematically searched MEDLINE, Web of Science, Scopus, and EMBASE for subject headings and text words related to CDI and pediatrics from 1975 to 2017. Two of the investigators independently screened studies, extracted and compiled data, assessed study quality, and performed the meta-analysis.

Results:

Of the 2,033 articles screened, 14 studies reporting 10,531,669 children met the inclusion criteria. Prior antibiotic exposure (odds ratio [OR], 2.14; 95% confidence interval [CI], 1.31–3.52) and proton pump inhibitor (PPI) use (OR, 1.33; 95% CI, 1.07–1.64) were associated with an increased risk of CDI in children. Subgroup analyses using studies reporting only adjusted results suggested that prior antibiotic exposure is not a significant risk factor for CDI. H2 receptor antagonist (H2RA) use (OR, 1.36; 95% CI, 0.31–5.98) and that female gender (OR, 0.87; 95% CI, 0.74–1.03) did not play a significant role as a risk factor for developing CDI.

Conclusion:

Prior antibiotic exposure appears to be an important risk factor for CDI based on the combined analysis but not significant using adjusted studies. PPI use was associated with an increased risk of CDI. Judicious and appropriate use of antibiotics and PPIs may help reduce the risk of CDI in this vulnerable population.

Adverse Effects of Intravenous Vancomycin-Based Prophylaxis during Therapy for Pediatric Acute Myeloid Leukemia

Children and adolescents with acute myeloid leukemia (AML) are at risk of life-threatening bacterial infections, especially with viridans group streptococci. Primary antibacterial prophylaxis with vancomycin-based regimens reduces this risk but might increase the risks of renal or liver toxicity or Clostridium difficile infection (CDI). A retrospective review of data for patients treated for newly diagnosed AML at St. Jude Children's Research Hospital between 2002 and 2008 was conducted. Nephrotoxicity was classified according to pediatric risk, injury, failure, loss, and end-stage renal disease (pRIFLE) criteria and hepatotoxicity according to Common Terminology Criteria for Adverse Events (CTCAE) criteria. The risks of nephrotoxicity, hepatotoxicity, and CDI were compared between patients receiving vancomycin-based prophylaxis, no intravenous prophylaxis, or other prophylaxis. Generalized linear mixed models were used to address potential confounding. A total of 392 chemotherapy courses (108 with no intravenous prophylaxis, 218 with vancomycin-based prophylaxis, and 66 with other prophylaxis) for 111 patients were included. Development of pRIFLE risk, injury, and failure occurred in 190, 44, and 2 courses, respectively. Increases of at least one, two, and three grades for hepatotoxicity occurred in 189, 52, and 19 courses, respectively. After adjustment for confounders, vancomycin-based prophylaxis was not associated with nephrotoxicity or hepatotoxicity and reduced the risk of CDI, compared to no intravenous prophylaxis (0.9% versus 6.5%; P = 0.007) or other prophylactic regimens (0.9% versus 3.0%; P = 0.23). Despite concerns about vancomycin toxicity, vancomycin-based prophylaxis in pediatric patients with AML did not increase the risk of nephrotoxicity or hepatotoxicity and reduced the risk of CDI. Caution is advised to avoid contributing to antibiotic resistance.

Evaluation of bloodstream infections, Clostridium difficile infections, and gut microbiota in pediatric oncology patients

Bloodstream infections (BSI) and Clostridium difficile infections (CDI) in pediatric oncology/hematology/bone marrow transplant (BMT) populations are associated with significant morbidity and mortality. The objective of this study was to explore possible associations between altered microbiome composition and the occurrence of BSI and CDI in a cohort of pediatric oncology patients. Stool samples were collected from all patients admitted to the pediatric oncology floor from Oct.-Dec. 2012. Bacterial profiles from patient stools were determined by bacterial 16S rRNA gene profiling. Differences in overall microbiome composition were assessed by a permutation-based multivariate analysis of variance test, while differences in the relative abundances of specific taxa were assessed by Kruskal-Wallis tests. At admission, 9 of 42 patients (21%) were colonized with C. difficile, while 6 of 42 (14%) subsequently developed a CDI. Furthermore, 3 patients (7%) previously had a BSI and 6 patients (14%) subsequently developed a BSI. Differences in overall microbiome composition were significantly associated with disease type (p = 0.0086), chemotherapy treatment (p = 0.018), BSI following admission from any cause (p < 0.0001) or suspected gastrointestinal organisms (p = 0.00043). No differences in baseline microbiota were observed between individuals who did or did not subsequently develop C. difficile infection. Additionally, multiple bacterial groups varied significantly between subjects with post-admission BSI compared with no BSI. Our results suggest that differences in gut microbiota not only are associated with type of cancer and chemotherapy, but may also be predictive of subsequent bloodstream infection.

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.

Selected Topics in Anaerobic Bacteriology

Alteration in the host microbiome at skin and mucosal surfaces plays a role in the function of the immune system, and may predispose immunocompromised patients to infection. Because obligate anaerobes are the predominant type of bacteria present in humans at skin and mucosal surfaces, immunocompromised patients are at increased risk for serious invasive infection due to anaerobes. Laboratory approaches to the diagnosis of anaerobe infections that occur due to pyogenic, polymicrobial, or toxin-producing organisms are described. The clinical interpretation and limitations of anaerobe recovery from specimens, anaerobe-identification procedures, and antibiotic-susceptibility testing are outlined. Bacteriotherapy following analysis of disruption of the host microbiome has been effective for treatment of refractory or recurrent Clostridium difficile infection, and may become feasible for other conditions in the future.

Infectious complications in children with acute lymphoblastic leukemia treated in low-middle-income countries

Infections are the most important cause of morbidity and mortality in children treated for acute lymphoblastic leukemia (ALL). The rates of infection-associated mortality are up to 10-times higher in low- and middle-income countries (LMIC) than in high-income countries. The prevention, early recognition and management of infectious complications is especially challenging in LMIC because of disease and poverty-related factors, as well as the shortage of trained personnel, supplies, diagnostic tools and adequate organizational infrastructure. Children in LMIC with ALL, who are frequently underweight, are at increased risk of community-acquired pathogens, nosocomial multidrug-resistant pathogens and opportunistic microorganisms. This review summarizes the challenges of managing the major categories of infections in children receiving treatment for ALL and provides updated practical recommendations for preventing and managing these infections in LMIC.

Risk factors for the development of Clostridium difficile infection in hospitalized children

PURPOSE OF REVIEW

This article defines the risk factors for Clostridium difficile infection (CDI) in hospitalized children in light of recent studies demonstrating a change in the epidemiology of these infections in both adults and children.

RECENT FINDINGS

Antibiotic exposure within the past 4-12 weeks was noted in a majority of published cases of pediatric CDI, and that remains a key risk factor for infection. Past and/or prolonged hospitalization increase a child's risk for CDI as they increase potential contact with C. difficile spores. Of all CDI, hospital-acquired infection remains more common. Many comorbid conditions have been linked with CDI, with the strongest association existing in children with cancer and inflammatory bowel disease. Severe infections occur infrequently in pediatric patients. Markers established in adults for severe CDI resulting in colectomy or transfer to ICU have not been shown to correlate in pediatric patients.

SUMMARY

Recent antibiotic exposure and hospitalization remain key risk factors for CDI in the hospitalized pediatric patient. Patients with comorbid conditions such as malignancy and inflammatory bowel disease are at higher risk for CDI. Resistant infections and severe outcomes are not common in the pediatric population.