Severity of acute gastrointestinal graft-vs-host disease is associated with incidence of bloodstream infection after adult allogeneic hematopoietic stem cell transplantation

Incidence of bacterial blood stream infections in patients with acute GVHD

Bacterial bloodstream infections (BSI) can be a substantial contributor to complications of GVHD treatment. The aim of this study was to determine the risk for BSI from neutrophil engraftment through day 100 post transplant in patients with acute GVHD (AGVHD) based on organ involvement and severity. Patients (n = 4064) who underwent an allogeneic hematopoietic stem cell transplant (HCT) reported to the CIBMTR registry were analyzed. Grade II-IV AGVHD occurred in 1607 (39.5%) patients and was associated with a greater day-100 incidence of post engraftment BSI than with grade 0/I (24.9 vs. 15.3%). Patients with grade III/IV AGVHD had the highest BSI risk (HR 2.45; 95% CI 1.99-3.0; p < 0.0001). Lower GI involvement increased BSI risk (HR 1.54; 95% CI 1.17-2.02; p = 0.0019). BSI post-engraftment through day 100 was associated with worse survival (HR 1.64, 95% CI 1.43-1.87; p < 0.001) and higher non-relapse mortality (NRM), (HR 2.22; 95% CI 1.91-2.59; p < 0.001). Those with stage III/IV GI involvement are at highest risk for BSI. Future studies evaluating novel methods for preventing BSI in these high risk populations are needed to reduce mortality associated with AGVHD.

Epidemiology, Microbiology, and Risk Factors of Bacterial Bloodstream Infections in Patients After Allogeneic Hematopoietic Stem Cell Transplantation

Purpose

To investigate the clinical characteristics, etiology, and risk factors of bacterial bloodstream infection (BSI) in allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients. This study also aimed to provide a clinical basis for early identification of high-risk patients and optimization of empirical antimicrobial treatment.

Patients and Methods

This is a retrospective study of clinical data during agranulocytosis from 331 patients with hematological malignancies who underwent allo-HSCT at our institute between January 2016 and December 2022. The incidence, distribution and drug resistance patterns, and the risk factors of BSI were analyzed.

Results

Among the 331 HSCT patients, 250 had febrile neutropenia and 45 cases were found to have BSI. The incidence of BSI in patients with agranulocytosis fever was 18% (45/250). A total of 48 pathogens were isolated during BSI episodes, gram-negative bacteria (GNB) accounted for 70.8% (34/48), gram-positive bacteria (GPB) for 29.2% (14/48). Multivariate analysis revealed that ≥grade 2 acute graft-versus-host disease (aGVHD) and previous BSI within 6 months before HSCT were independently associated with an increased occurrence of BSI. Coagulase-negative staphylococci (CoNS) and Escherichia coli were the most commonly isolated GPB and GNB, respectively. A total of 32 GNB were tested for drug susceptibility, the detection rate of carbapenem-resistant Enterobacteriaceae (CRE) was 12.5% (4/32), and extended-spectrum β-lactamase (ESBL) accounted for 56.3% (18/32).

Conclusion

BSIs are still a common and severe complication after allo-HSCT. In our center, BSIs in allo-HSCT patients are dominated by gram-negative bacteria and the resistance rate to carbapenem drugs is high. Risk factors for BSI during agranulocytosis were previous BSI within 6 months before HSCT and ≥grade 2 aGVHD.

Incidence, Etiology, Risk Factors, and Outcomes of Bloodstream Infection after a Second Hematopoietic Stem Cell Transplantation

Objective Infections after a second hematopoietic stem cell transplantation (HSCT) occur commonly and are associated with high mortality. However, studies on bloodstream infection (BSI) after a second HSCT are lacking. We therefore evaluated the details of BSI after a second HSCT. Methods We retrospectively evaluated the incidence, etiology, risk factors, and outcomes of BSI after a second HSCT. Patients Fifty-two adult patients with hematological malignancies who underwent allogeneic HSCT, including cord blood transplantation (CBT; n=33), as the second transplantation were enrolled. The second transplantation was limited to allogeneic HSCT. Patients who underwent HSCT for graft failure were excluded. Results The median HSCT interval was 438 (range: 39-3,893) days. Overall, 31 (59.6%) patients received autologous HSCT as the first HSCT. The cumulative incidence of BSI was 40.4% at 100 days after the second HSCT, with Gram-positive bacteria accounting for the majority (30.8%) of pathogens. Overall, 92.0% of BSIs occurred during the pre-engraftment period, and Enterococcus faecium accounted for 29.6% of pathogens. On a multivariate analysis, CBT was most closely associated with pre-engraftment BSI after the second HSCT (hazard ratio: 3.43, 95% confidence interval: 1.05-11.23, p=0.042). The 1-year survival rate after the second HSCT was lower in patients with BSI than in patients without BSI (p=0.10). Conclusion BSI is common after a second HSCT, especially with CBT. During the pre-engraftment period, BSI caused by pathogens such as E. faecium should be anticipated and appropriately treated to improve transplant outcomes.

Phase 2 study of natalizumab plus standard corticosteroid treatment for high-risk acute graft-versus-host disease

Graft-versus-host disease (GVHD) of the gastrointestinal (GI) tract is the main cause of nonrelapse mortality (NRM) after allogeneic hematopoietic cell transplantation. Ann Arbor (AA) scores derived from serum biomarkers at onset of GVHD quantify GI crypt damage; AA2/3 scores correlate with resistance to treatment and higher NRM. We conducted a multicenter, phase 2 study using natalizumab, a humanized monoclonal antibody that blocks T-cell trafficking to the GI tract through the α4 subunit of α4β7 integrin, combined with corticosteroids as primary treatment for patients with new onset AA2/3 GVHD. Seventy-five patients who were evaluable were enrolled and treated; 81% received natalizumab within 2 days of starting corticosteroids. Therapy was well tolerated with no treatment emergent adverse events in >10% of patients. Outcomes for patients treated with natalizumab plus corticosteroids were compared with 150 well-matched controls from the MAGIC database whose primary treatment was corticosteroids alone. There were no significant differences in overall or complete response between patients treated with natalizumab plus corticosteroids and those treated with corticosteroids alone (60% vs 58%; P = .67% and 48% vs 48%; P = 1.0, respectively) including relevant subgroups. There were also no significant differences in NRM or overall survival at 12 months in patients treated with natalizumab plus corticosteroids compared with controls treated with corticosteroids alone (38% vs 39%; P = .80% and 46% vs 54%; P = .48, respectively). In this multicenter biomarker-based phase 2 study, natalizumab combined with corticosteroids failed to improve outcome of patients with newly diagnosed high-risk GVHD. This trial was registered at www.clinicaltrials.gov as # NCT02133924.

Impact of intensified contact precautions while treating hematopoietic stem cell transplantation recipients during aplasia

BACKGROUND

Bacterial infections are a major complication for patients undergoing allogeneic hematopoietic stem cell transplantation (HCT). Therefore, protective isolation is considered crucial to prevent nosocomial infections in this population. Here, the impact of intensified contact precautions on environmental contamination and the occurrence of bloodstream infections (BSI) in patients on a HCT unit were compared between two contact precaution measures.

METHODS

A 2-year retrospective observational study was performed. In the first year, strict contact precaution measures were applied (i.e., protective isolation, the use of sterile personal protective equipment (PPE) by healthcare workers and visitors and sterilization of linen and objects that entered the patient's room). After one year, contact precautions were reduced (i.e., no use of sterile PPE, no sterilization of linen and objects that entered the patient's room). Environmental contamination in randomly selected patient rooms was monitored by sampling six standardized environmental sites in the respective patient treatment units. In a before-and-after study, the number of BSI episodes of those patients, who were accommodated in the monitored rooms was compared.

RESULTS

In total, 181 treatment units were monitored. No significant difference in the contamination of anterooms and patient's rooms between both groups was found. A total of 168 patients were followed for the occurrence of BSI during the entire study period (before: 84 patients, after: 84 patients). The total count of patients with BSI episodes showed a higher incidence in the period with reduced contact precautions (30/84 vs. 17/84, p = 0.039). The cause of this increasing number of BSI can be traced back to BSI episodes with common commensal bacteria (17/84 vs. 5/84, p = 0.011).

CONCLUSIONS

The implementation of maximal barrier measures did not reduce the bacterial contamination of the patients' environment. The impact on the patients' outcomes remain controversial. Further research is needed to investigate the impact of infection prevention measures on the clinical outcome of patients undergoing HCT.

Efficacy and safety of ruxolitinib in steroid-refractory graft-versus-host disease: A meta-analysis

Ruxolitinib is an important treatment for steroid refractory graft-versus-host disease (SR-GVHD). Therefore, we reported the updated results of a systematic review and meta-analysis of ruxolitinib as treatment for SR-GVHD. In addition, we wanted to compare the efficacy and safety between children and adults with SR-GVHD. Overall response rate (ORR) after ruxolitinib treatment was chosen as the primary end point. Complete response rate (CRR), infection, myelosuppression, and overall survival (OS) were chosen as secondary end points. A total of 37 studies were included in this meta-analysis, and 1,580 patients were enrolled. ORR at any time after ruxolitinib treatment was 0.77 [95% confidence interval (CI): 0.68–0.84] and 0.78 (95% CI: 0.74–0.81), respectively, for SR-aGVHD and SR-cGVHD. CRR at any time after ruxolitinib treatment was 0.49 (95% CI: 0.40–0.57) and 0.15 (95% CI: 0.10–0.23), respectively, for SR-aGVHD and SR-cGVHD. The ORRs at any time after treatment was highest in mouth SR-cGVHD, followed by skin, gut, joints and fascia, liver, eyes, esophagus, and lung SR-cGVHD. The incidence rate of infections after ruxolitinib treatment was 0.61 (95% CI: 0.45–0.76) and 0.47 (95% CI: 0.31–0.63), respectively, for SR-aGVHD and SR-cGVHD. The incidence rates of overall (grades I–IV) and severe (grades III–IV) cytopenia were 53.2% (95% CI: 16.0%–90.4%) and 31.0% (95% CI: 0.0–100.0%), respectively, for SR-aGVHD, and were 28.8% (95% CI:13.0%–44.6%) and 10.4% (95% CI: 0.0–27.9%), respectively, for SR-cGVHD. The probability rate of OS at 6 months after treatment was 63.9% (95% CI: 52.5%–75.2%) for SR-aGVHD. The probability rates of OS at 6 months, 1 year, and 2 years after treatment were 95% (95% CI: 79.5%–100.0%), 78.7% (95% CI: 67.2%–90.1%), and 75.3% (95% CI: 68.0%–82.7%), respectively, for SR-cGVHD. The ORR, CRR, infection events, and myelosuppression were all comparable between children and adults with SR-GVHD. In summary, this study suggests that ruxolitinib is an effective and safe treatment for SR-GVHD, and both children and adults with SR-GVHD could benefit from ruxolitinib treatment.

A comprehensive model to predict severe acute graft-versus-host disease in acute leukemia patients after haploidentical hematopoietic stem cell transplantation

BACKGROUND

Acute graft-versus-host disease (aGVHD) remains the major cause of early mortality after haploidentical related donor (HID) hematopoietic stem cell transplantation (HSCT). We aimed to establish a comprehensive model which could predict severe aGVHD after HID HSCT.

METHODS

Consecutive 470 acute leukemia patients receiving HID HSCT according to the protocol registered at https://clinicaltrials.gov (NCT03756675) were enrolled, 70% of them (n = 335) were randomly selected as training cohort and the remains 30% (n = 135) were used as validation cohort.

RESULTS

The equation was as follows: Probability (grade III-IV aGVHD) = [Formula: see text], where Y = -0.0288 × (age) + 0.7965 × (gender) + 0.8371 × (CD3 + /CD14 + cells ratio in graft) + 0.5829 × (donor/recipient relation) - 0.0089 × (CD8 + cell counts in graft) - 2.9046. The threshold of probability was 0.057392 which helped separate patients into high- and low-risk groups. The 100-day cumulative incidence of grade III-IV aGVHD in the low- and high-risk groups was 4.1% (95% CI 1.9-6.3%) versus 12.8% (95% CI 7.4-18.2%) (P = 0.001), 3.2% (95% CI 1.2-5.1%) versus 10.6% (95% CI 4.7-16.5%) (P = 0.006), and 6.1% (95% CI 1.3-10.9%) versus 19.4% (95% CI 6.3-32.5%) (P = 0.017), respectively, in total, training, and validation cohort. The rates of grade III-IV skin and gut aGVHD in high-risk group were both significantly higher than those of low-risk group. This model could also predict grade II-IV and grade I-IV aGVHD.

CONCLUSIONS

We established a model which could predict the development of severe aGVHD in HID HSCT recipients.

Origins of bloodstream infections following fecal microbiota transplantation: a strain-level analysis

We observed high rates of bloodstream infections (BSIs) following fecal microbiota transplantation (FMT) for graft-versus-host-disease (33 events in 22 patients). To trace the BSIs' origin, we applied a metagenomic bioinformatic pipeline screening donor and recipient stool samples for bacteremia-causing strains in 13 cases. Offending strains were not detected in FMT donations. Enterococcus faecium, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii could be detected in stool samples before emerging in the blood. In this largest report of BSIs post-FMT, we present an approach that may be applicable for evaluating BSI origin following microbiota-based interventions. Our findings support FMT safety in immunocompromised patients but do not rule out FMT as an inducer of bacterial translocation.

Levofloxacin Versus Ciprofloxacin-Based Prophylaxis during the Pre-Engraftment Phase in Allogeneic Hematopoietic Stem Cell Transplant Pediatric Recipients: A Single-Center Retrospective Matched Analysis

Infectious complications are the most common and significant cause of mortality and morbidity after allogeneic hematopoietic stem cell transplantation (HSCT). Antibacterial prophylaxis in pediatric cancer patients is a controversial issue. Our study compared the outcomes of levofloxacin versus ciprofloxacin prophylaxis in allogeneic HSCT pediatric recipients treated for hematological malignancies. A total of 120 patients received levofloxacin prophylaxis, and 60 patients received ciprofloxacin prophylaxis. Baseline characteristics such as age, gender, primary diagnosis, type of conditioning, donor type, stem cell source, and supportive care of the patients were similar, and duration of antibiotics prophylaxis was similar. Both prophylaxis regimens demonstrated the same efficacy on the risk of febrile neutropenia and severe complications such as sepsis, the same rate of overall mortality, hospital readmission, and length of hospital stay. Levofloxacin prophylaxis was associated with significantly lower cumulative antibiotic exposure. The median of Gram-positive infection-related antibiotic days was 10 days in the levofloxacin group versus 25 days in the ciprofloxacin group (p < 0.0001). The median of Gram-negative infection-related antibiotics was 10 days in the levofloxacin group compared with 20 days in the ciprofloxacin group (p < 0.0001). The number of days with body temperature ≥38 °C was significantly less in the levofloxacin group (p < 0.001).

Severe infections and infection-related mortality in a large series of haploidentical hematopoietic stem cell transplantation with post-transplant cyclophosphamide

Severe infections and their attributable mortality are major complications in recipients of allogeneic hematopoietic stem cell transplantation (alloSCT). We herein report 236 adult patients who received haploSCT with PTCy. The median follow-up for survivors was 37 months. The overall incidence of bloodstream infections by gram-positive and gram-negative bacteria at 37 months was 51% and 46%, respectively. The incidence of cytomegalovirus infection was 69%, while Epstein Barr virus infections occurred in 10% of patients and hemorrhagic cystitis in 35% of cases. Invasive fungal infections occurred in 11% at 17 months. The 3-year incidence of infection-related mortality was 19%. The median interval from transplant to IRM was 3 months (range 1-30), 53% of IRM occurred >100 days post-haploSCT. Risk factors for IRM included age >50 years, lymphoid malignancy, and developing grade III-IV acute GvHD. Bacterial infections were the most common causes of IRM (51%), mainly due to gram-negative bacilli BSI. In conclusion, severe infections are the most common causes of NRM after haploSCT with PTCy, with a reemergence of gram-negative bacilli as the most lethal pathogens. More studies focusing on the severe infections after haploSCT with PTCy and differences with other types of alloSCT in adults are clearly warranted.

How we can mitigate the side effects associated with systemic glucocorticoid after allogeneic hematopoietic cell transplantation

Allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative treatment for patients with a hematologic disease. Although the clinical outcomes after allo-HCT have significantly improved during the last few decades, graft-versus-host disease (GVHD) is still a major cause of post-HCT morbidity and mortality. Systemic glucocorticoids (GC) remain an integral part of treatment in patients with GVHD including both acute and chronic GVHD. Although it is well-known that usage of systemic GC is associated with various side effects, the short- and long-term effects of GCs in the HCT setting are not well-characterized due to limited published data. In order to clarify this issue, we summarize the information on side effects associated with GCs, focusing specifically on the sequelae of these agents in the early post-HCT period. In instances where limited data are available, we included data from other fields such as autoimmune diseases, given the potential parallels between autoimmune conditions and GVHD.

Casting a wider protective net: Anti-infective vaccine strategies for patients with hematologic malignancy and blood and marrow transplantation

Patients who have hematologic malignancies are at high risk for infections but vaccinations may be effective prophylaxis. The increased infection risk derives from immune defects secondary to malignancy, the classic example being CLL, and chemotherapies and immunotherapy used to treat the malignancies. Therapy of hematologic malignancies is being revolutionized by introduction of novel targeted agents and immunomodulatory medications, improving the survival of patients. At the same time those agents uniquely change the infection risk and response to immunizations. This review will summarize current vaccine recommendations for patients with hematologic malignancies including patients who undergo hematopoietic cell transplant.