Surveillance cultures in pediatric allogeneic hematopoietic stem cell transplantation

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

Prevalence of Clostridium difficile Infection in the Hematopoietic Transplantation Setting: Update of Systematic Review and Meta-Analysis

Hematopoietic stem cell transplant (HSCT) recipients are vulnerable to Clostridium difficile infection (CDI) due to risk factors such as immunosuppression, antimicrobial use, and frequent hospitalization. We systematically searched PubMed and Embase to screen relevant studies from April 2014 to November 2021. A meta-analysis was performed to identify the association between CDI and hematopoietic transplantation based on the standard mean difference and 95% confidence intervals (CIs). Among the 431 retrieved citations, we obtained 43 eligible articles, which included 15,911 HSCT patients at risk. The overall estimated prevalence of CDI was 13.2%. The prevalence of CDI among the 10,685 allogeneic transplantation patients (15.3%) was significantly higher than that among the 3,840 autologous HSCT recipients (9.2%). Different incidence rates of CDI diagnosis over the last 7 years were found worldwide, of which North America (14.1%) was significantly higher than Europe (10.7%) but not significantly different from the prevalence among Asia (11.6%). Notably, we found that the estimated prevalence of CDI diagnosed by polymerase chain reaction (PCR) (17.7%) was significantly higher than that diagnosed by enzyme immunoassay (11.5%), indicating a significant discrepancy in the incidence rate of CDI owing to differences in the sensibility and specificity of the detection methods. Recurrence of CDI was found in approximately 15% of the initial patients with CDI. Furthermore, 20.3% of CDI cases were severe. CDI was found to be a common complication among HSCT recipients, displaying an evident increase in the morbidity of infection.

Gut Colonization Preceding Mucosal Barrier Injury Bloodstream Infection in Pediatric Hematopoietic Stem Cell Transplantation Recipients

The gastrointestinal tract is the predicted reservoir for most bloodstream infections (BSIs) after hematopoietic stem cell transplantation (HSCT). Whole-genome sequencing and comparative genomics have the potential to improve our understanding of the dynamics of gut colonization that precede BSI in HSCT recipients. Within a prospective cohort study of children (age <18 years) undergoing HSCT, 9 subjects met criteria for mucosal barrier injury BSI. We performed whole-genome sequencing of the blood culture isolate and weekly fecal samples preceding the BSI to compare the genetic similarity of BSI isolates to fecal strains. We evaluated temporal associations between antibiotic exposures and the abundances of BSI strains in the gut microbiota and correlated the detection of antibiotic resistance genes with the phenotypic antibiotic resistance of these strains. The median patient age was 2.6 years, and 78% were male. BSIs were caused by Escherichia coli (n = 5), Enterococcus faecium (n = 2), Enterobacter cloacae (n = 1), and Rothia mucilaginosa (n = 1). In the 6 BSI episodes with evaluable comparative genomics, the fecal strains were identical to the blood culture isolate (>99.99% genetic similarity). Gut domination by these strains preceded only 4 of 7 E. coli or E. faecium BSIs by a median of 17 days (range, 6 to 21 days). Increasing abundances of the resulting BSI strains in the gut microbiota were frequently associated with specific antibiotic exposures. E. cloacae and R. mucilaginosa were not highly abundant in fecal samples preceding BSIs caused by these species. The detection of antibiotic resistance genes for β-lactam antibiotics and vancomycin predicted phenotypic resistance in BSI strains. Bacterial strains causing mucosal barrier injury BSI in pediatric HSCT recipients were observed in the gut microbiota before BSI onset, and changes in the abundances of these strains within the gut preceded most BSI episodes. However, frequent sampling of the gut microbiota and sampling of other ecological niches is likely necessary to effectively predict BSI in HSCT recipients.

Indian Antimicrobial Prescription Guidelines in Critically Ill Immunocompromised Patients

How to cite this article: Kulkarni AP, Sengar M, Chinnaswamy G, Hegde A, Rodrigues C, Soman R, Khilnani GC, Ramasubban S, Desai M, Pandit R, Khasne R, Shetty A, Gilada T, Bhosale S, Kothekar A, Dixit S, Zirpe K, Mehta Y, Pulinilkunnathil JG, Bhagat V, Khan MS, Narkhede AM, Baliga N, Ammapalli S, Bamne S, Turkar S, Bhat KV, Choudhary J, Kumar R, Divatia JV. Indian Journal of Critical Care Medicine 2019;23(Suppl 1): S64-S96.

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.