Enterococcal bacteremia is associated with increased risk of mortality in recipients of allogeneic hematopoietic stem cell transplantation

BACKGROUND

Enterococci are an important cause of healthcare-associated infections. We retrospectively analyzed risk factors and outcome of vancomycin-resistant enterococci (VRE) and vancomycin-sensitive enterococci (VSE) infections.

METHODS

Seven hundred fifty-two patients who received hematopoietic stem cell transplants from 2004 through 2008 at the University of Minnesota were included.

RESULTS

Ninety-three patients had enterococcal bloodstream infection (BSI) during the first year after transplant. Vancomycin resistance was observed in 66% and 31% of isolates in adults and children, respectively. Cumulative incidence of VRE and VSE bacteremia was 6.6% (95% confidence interval [CI], 4.8%-8.4%) and 5.7% (95% CI, 4.0%-7.4%), respectively. Colonization with VRE before or after transplant was a risk factor for VRE bacteremia (odds ratio [OR], 3.3 [95% CI, 1.3-8.3] and 7.0 [95% CI, 4.0-14.8], respectively). Delay in engraftment increased the incidence of VRE bacteremia from 4.5% (95% CI, 2.9-6.6) if engrafted before day 21 and to 15% (95% CI, 3.2%-38%) if engrafted between days 36 and 42. In adults, mortality 30 days after infection was 38% for both VRE (95% CI, 25%-54%) and VSE cases (95% CI, 21%-62%). The hazard ratio for all-cause mortality up to 1 year after transplant was 4.2 (95% CI, 3.1-6.9) and 2.7 (95% CI, 1.4-5.1) for patients with VRE and VSE BSIs, respectively, compared to patients without enterococcal BSI. In pediatric patients, mortality 30 days after VRE and VSE bacteremia was 20% (95% CI, 5.4%-59%) and 4.5% (95% CI, .6%-28%), respectively.

CONCLUSION

High rates of vancomycin resistance and association of enterococcal infections with significant mortality warrant further efforts to optimize prevention and management of these infections.

Human parainfluenza virus infection after hematopoietic stem cell transplantation: risk factors, management, mortality, and changes over time

Human parainfluenza viruses (HPIVs) are uncommon, yet high-risk pathogens after hematopoietic stem cell transplant (HCT). We evaluated 5178 pediatric and adult patients undergoing HCT between 1974 and 2010 to determine the incidence, risk factors, response to treatment, and outcome of HPIV infection as well as any change in frequency or character of HPIV infection over time. HPIV was identified in 173 patients (3.3%); type 3 was most common (66%). HPIV involved upper respiratory tract infection (URTI; 57%), lower respiratory tract infection (LRTI; 9%), and both areas of the respiratory tract (34%), at a median of 62 days after transplantation. In more recent years, HPIV has occurred later after HCT, whereas the proportion with nosocomial infection and mortality decreased. Over the last decade, HPIV was more common in older patients and in those receiving reduced intensity conditioning (RIC). RIC was a significant risk factor for later (beyond day +30). HPIV infections, and this association was strongest in patients with URTI. HCT using a matched unrelated donor (MURD), mismatched related donor (MMRD), age 10 to 19 years, and graft-versus-host disease (GVHD) were all risk factors for HPIV infections. LRTI, early (<30 days), age 10 to 19 years, MMRD, steroid use, and coinfection with other pathogens were risk factors for mortality. The survival of patients with LRTI, especially very early infections, was poor regardless of ribavirin treatment. HPIV incidence remains low, but may have delayed onset associated with RIC regimens and improving survival. Effective prophylaxis and treatment for HPIV are needed.

Epidemiology and management of infectious complications of contemporary management of chronic leukemias

This is a review of the epidemiology and management of infectious complications of contemporary management of chronic leukemias. Patients with chronic leukemias typically are affected by nuisance infections due to the underlying hematologic condition, particularly hypogammaglobulinemia in CLL patients. With active treatment, particularly those agents that cause defects in cell-mediated immunity, the incidence of opportunistic infections increases although endogenous bacterial, mycobacterial, and fungal infections also occur. Exogenous treatment with immunoglobulin and antimicrobial prophylaxis, particularly anti-Pneumocystis prophylaxis, may be indicated in select patients. Routine vaccinations should be maintained in these patients and vaccination early in the course of treatment may result in improve protection.

Clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer: 2010 update by the infectious diseases society of america

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia. Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving. What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens. Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care-associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Human herpesvirus 6 infection after hematopoietic cell transplantation: is routine surveillance necessary?

Human herpesvirus 6 (HHV6) may be an important pathogen following allogeneic hematopoietic cell transplantation (HCT). We prospectively evaluated weekly HHV6 viremia testing after allogeneic HCT using a quantitative polymerase chain reaction (PCR)-based assay. HHV-6 viremia was detected in 46 of 82 (56%) patients at a median of 23 days post-HCT (range: day +10 to +168). More males (65% vs females 39%, P = .03) and recipients of umbilical cord blood (UCB 69% vs unrelated donor [URD], 46% vs sibling donor [20%] grafts, P = 0.01) reactivated HHV-6. Patients with HHV6 viremia had more cytomegalovirus (CMV) reactivation (26% vs 5.5%, P = .01) and unexplained fever and rash (23.9% vs 2.7%, P = .01) compared with patients without HHV6 viremia. High-level HHV6 (≥ 25,000 copies/mL) versus lower levels were associated with more culture-negative pneumonitis (72.7% vs 22.8%, P = .01). Twenty HHV6-positive patients were treated with foscarnet, ganciclovir, or cidofovir for HHV6 or other coexistent viruses. Within 2 weeks, HHV6 viremia resolved more commonly in treated (65%) than untreated patients (31%), P = .02. Survival at 3 months was similar in treated and untreated patients (90% vs 81%, P = .4). Survival at 3 and 6 months post-HCT were not affected by HHV6 positivity (3 months HHV6+ 85% vs 78%, P = .46; 6 months HHV6+ 70% vs 72%, P = .89) or by HHV6 level (3-month high level 73% vs 89%, P = .23; 6-month high level 64% vs 71%, P = .54). Neither the occurrence of HHV6, degree of viremia, nor use of antiviral drugs influenced short-term survival after HCT.

Maribavir prophylaxis for prevention of cytomegalovirus disease in recipients of allogeneic stem-cell transplants: a phase 3, double-blind, placebo-controlled, randomised trial

BACKGROUND

Available drugs against cytomegalovirus have adverse effects that compromise their prophylactic use in recipients of allogeneic stem-cell transplants. We assessed the safety, tolerability, and antiviral activity of oral maribavir in such patients.

METHODS

In this placebo-controlled, randomised, double-blind, multicentre phase 3 study, we enrolled adult patients recipient-seropositive or donor-seropositive for cytomegalovirus who had undergone allogeneic stem-cell transplantation. Patients were recruited from 90 centres in Canada, Europe, and the USA. After engraftment, patients were stratified by recipient cytomegalovirus serostatus and conditioning regimen (myeloablative or reduced-intensity) and assigned (2:1) by masked computer-generated randomisation sequence to receive maribavir 100 mg twice daily or placebo for up to 12 weeks, with weekly blood cytomegalovirus surveillance. If the virus was detected, administration of study drug was stopped and pre-emptive anticytomegalovirus treatment started. The primary endpoint was cytomegalovirus disease within 6 months of transplantation. Analysis was by intention-to-treat. This study is registered with ClinicalTrials.gov, NCT00411645.

FINDINGS

Between December, 2006, and May, 2008, 681 patients were enrolled and assigned to receive maribavir (454) or placebo (227). The incidence of cytomegalovirus disease within 6 months was 20 of 454 (4%) for the maribavir group and 11 of 227 (5%) for the placebo group (OR 0.90; 95% CI 0.42-1.92). During the 100 days following transplantation, cytomegalovirus infection rates as measured by pp65 antigenaemia were lower in the maribavir group (26.4%) than in the placebo group (34.8%; OR 0.67; 0.47-0.95), but not when measured by plasma cytomegalovirus DNA PCR (27.8%vs 30.4%; OR 0·88; 0.62-1.25), nor by initiation of treatment against cytomegalovirus (30.6%vs 37.4%; OR 0.73, 0.52-1.03). Maribavir was well tolerated: most adverse events, including incident acute graft-versus-host disease and neutropenia, affected both groups equally, except for taste disturbance (15% maribavir, 6% placebo).

INTERPRETATION

Compared with placebo, maribavir prophylaxis did not prevent cytomegalovirus disease when started after engraftment. Cytomegalovirus disease as a primary endpoint might not be sufficient to show improvements in cytomegalovirus prevention in recipients of allogeneic stem-cell transplants in the setting of pre-emptive antiviral treatment. Clinical and virological composite endpoints should be used in future trials.

FUNDING

ViroPharma Incorporated.

Executive Summary: Clinical Practice Guideline for the Use of Antimicrobial Agents in Neutropenic Patients with Cancer: 2010 Update by the Infectious Diseases Society of America

This document updates and expands the initial Infectious Diseases Society of America (IDSA) Fever and Neutropenia Guideline that was published in 1997 and first updated in 2002. It is intended as a guide for the use of antimicrobial agents in managing patients with cancer who experience chemotherapy-induced fever and neutropenia.

Recent advances in antimicrobial drug development and technology, clinical trial results, and extensive clinical experience have informed the approaches and recommendations herein. Because the previous iteration of this guideline in 2002, we have a developed a clearer definition of which populations of patients with cancer may benefit most from antibiotic, antifungal, and antiviral prophylaxis. Furthermore, categorizing neutropenic patients as being at high risk or low risk for infection according to presenting signs and symptoms, underlying cancer, type of therapy, and medical comorbidities has become essential to the treatment algorithm. Risk stratification is a recommended starting point for managing patients with fever and neutropenia. In addition, earlier detection of invasive fungal infections has led to debate regarding optimal use of empirical or preemptive antifungal therapy, although algorithms are still evolving.

What has not changed is the indication for immediate empirical antibiotic therapy. It remains true that all patients who present with fever and neutropenia should be treated swiftly and broadly with antibiotics to treat both gram-positive and gram-negative pathogens.

Finally, we note that all Panel members are from institutions in the United States or Canada; thus, these guidelines were developed in the context of North American practices. Some recommendations may not be as applicable outside of North America, in areas where differences in available antibiotics, in the predominant pathogens, and/or in health care–associated economic conditions exist. Regardless of venue, clinical vigilance and immediate treatment are the universal keys to managing neutropenic patients with fever and/or infection.

Decreased infections in recipients of unrelated donor hematopoietic cell transplantation from donors with an activating KIR genotype

Infectious complications following allogeneic hematopoietic cell transplantation (HCT) from unrelated donors (URD) result in significant morbidity. We hypothesized that recipients of a URD with an activating natural killer cell immunoglobulin-like receptor (KIR) (B/x) genotype would have decreased infectious complications because of enhanced natural killer (NK) cell function. We compared the infectious complications in 116 recipients of a graft from a donor with an A/A KIR (n = 44) genotype and a B/x KIR (n = 72) genotype. All recipients participated in the prospective National Marrow Donor Program infection project collecting infection data from conditioning until 6 months posttransplant. The cohort with a B/x donor had fewer initial bacterial infections by day 180 (A/A: 86%; 95% confidence interval [CI], 75-95; B/x: 68%; 95% CI, 57-78; P = .02). There was no difference in the incidence of viral or fungal infections. When accounting for multiple infections, fewer bacterial infections were seen in the B/x cohort (A/A: 3.55/patient; B/x: 2.63/patient; P = .09). During the study period, only 19 patients had no infections; of these, 15 had received cells from a B/x KIR donor. The role of donor KIR genotype on infection complications is intriguing and warrants further investigation.

Time trends in fungal infections as a cause of death in hematopoietic stem cell transplant recipients: an autopsy study

Infectious complications remain an important cause of death in hematopoietic stem cell transplant (HSCT) recipients. We undertook a 20-year (1988-2007) retrospective review of all autopsies performed on HSCT recipients in our institution, with emphasis on infections, especially fungal infections, as the cause of death. Of the 2,943 autopsies performed in our institution from 1988 to 2007, 395 (13.4%) involved HSCT recipients (117 pediatric; 278 adult). Of the patients, 298 had received allogeneic, 46 autologous, 41 umbilical cord blood, and 3 autologous plus allogeneic types, and 7 were unknown HSCT types. The most common causes of death were pulmonary complications, occurring in 247 (62.5%) of 395 cases. In 178 cases (45.1%), microorganisms (viral, bacterial, and/or fungal) were documented at autopsy in one or more organs and contributed to the cause of death. Fungal infections were found in 23.5% of cases, but their frequency as a cause of death decreased throughout this study, from 30.3% in the 1988-1992 period to 10.9% in the 2003-2007 period.

Monitoring and preemptive rituximab therapy for Epstein-Barr virus reactivation after antithymocyte globulin containing nonmyeloablative conditioning for umbilical cord blood transplantation

Epstein Barr viremia (EBV) and posttransplantation lymphoproliferative disorder (PTLD) are complications of hematopoietic stem cell transplantation (HSCT). The use of antithymocyte globulin (ATG) in recipients of umbilical cord HSCT is a known risk factor for the development of PTLD. In this high-risk population, we implemented an EBV monitoring program with preemptive therapy with rituximab (375 mg/m(2) intravenously [i.v.]) for EBV viremia (>1000 copies/mL). Eight of 35 patients treated with a UCB HSCT between 2007 and 2009, developed EBV viremia. Two of 7 developed PTLD (with 1 of the 2 dying of PTLD), despite prophylactic rituximab use. When compared with our previously described cohort where 6 of 30 developed EBV viremia and 5 of 6 patients developed PTLD (with 2 of 5 dying of PTLD), the incidence of PTLD appears to be less when prophylactic rituximab is administered. Despite small numbers, our observations suggest that in this high-risk population, EBV monitoring accompanied by preemptive therapy may reduce the risk of progression to life-threatening PTLD; further follow-up of this cohort and a larger multi-institutional prospective study of this preemptive strategy is warranted.

Allogeneic hematopoietic cell transplantation in human immunodeficiency virus-positive patients with hematologic disorders: a report from the center for international blood and marrow transplant research

The role of allogeneic hematopoietic cell transplantation (alloHCT) in human immunodeficiency virus (HIV)-positive patients is not known. Using the Center for International Blood and Marrow Transplant Research database, we retrospectively evaluated 23 HIV-positive patients undergoing matched sibling donor (n = 19) or unrelated donor (n = 4) alloHCT between 1987 and 2003. The median age at alloHCT was 32 years. Indications for alloHCT were diverse and included malignant (n = 21) and nonmalignant (n = 2) hematologic disorders. Nine patients (39%) underwent transplantation after 1996, the approximate year that highly active antiretroviral therapy became standard treatment. The median time to neutrophil engraftment was 16 days (range, 7 to 30 days), and the cumulative incidences of grade II-IV acute graft-versus-host disease (aGVHD) at 100 days, chronic GVHD (cGVHD), and survival at 2 years were 30% (95% confidence interval [CI] = 14% to 50%), 28% (95% CI = 12% to 48%), and 30% (95% CI = 14% to 50%), respectively. At a median follow-up of 59 months, 6 patients were alive. Survival appears to be better in the patients undergoing alloHCT after 1996; 4 of these 9 patients survived, compared with only 2 of 14 those undergoing transplantation before 1996. These data suggest that alloHCT is feasible for selected HIV-positive patients with malignant and nonmalignant disorders. Prospective studies are needed to evaluate the safety and efficacy of this modality in specific diseases in these patients.

A Multicenter, double-blind trial of a high-dose caspofungin treatment regimen versus a standard caspofungin treatment regimen for adult patients with invasive candidiasis

BACKGROUND

The standard caspofungin treatment regimen (50 mg/day after a 70-mg dose on day 1) is effective and well tolerated for the treatment of invasive candidiasis, but experience with higher doses of caspofungin is limited. We evaluated the safety and efficacy of caspofungin at 3 times the standard dosing regimen.

METHODS

Patients with proven invasive candidiasis were randomized to receive a standard or high-dose (150 mg/day) caspofungin treatment regimen. Safety was assessed in all patients as treated. Efficacy was assessed as a secondary objective in a full-analysis-set population. A favorable overall response was defined as symptom resolution and microbiological clearance at the end of caspofungin therapy.

RESULTS

A total of 204 patients were included in the safety analysis (104 received the standard regimen, and 100 received the high-dose regimen), and 197 were included in the efficacy analysis (102 and 95 in the standard and high-dose treatment groups, respectively). Patient demographic characteristics, neutropenia status (6.7% and 8.0% had neutropenia, respectively), and Acute Physiology and Chronic Health Evaluation II scores (mean, 16.5 and 17, respectively) were similar between treatment groups. Significant drug-related adverse events occurred in 1.9% of patients receiving the standard regimen and 3.0% of patients receiving the high-dose regimen (difference, 1.1%; 95% confidence interval, -4.1% to 6.8%). The most-common drug-related adverse events in the standard and high-dose treatment groups were phlebitis (3.8% and 2.0%, respectively), increased alkaline phosphatase level (6.9% and 2.0%, respectively), and increased aspartate transaminase level (4.0% and 2.0%, respectively). Overall, 71.6% of patients who received the standard regimen and 77.9% of patients who received the high-dose regimen had favorable overall responses (difference, 6.3%; 95% confidence interval, -5.9% to 18.4%; not statistically significant). Mortality at 8 weeks after therapy was similar between groups.

CONCLUSIONS

Both caspofungin dosing regimens were effective and well tolerated in patients with invasive candidiasis. No safety concerns were found for caspofungin at a dosage of 150 mg/day.

Infectious complications of acute and chronic GVHD

Immune defects prolonged by treatment regimens for graft-versus-host disease (GVHD) include cell-mediated immunity and hypogammaglobulinemia. Infections have become increasingly important during GVHD therapy, paradoxically because the success of immunosuppressive practice has led to improved survival. Infections originate from both endogenous and exogenous sources. Regimens for prevention of infection include: (a) continued surveillance monitoring for infections with reliable diagnostic testing, and (b) antimicrobial prophylaxis for those pathogens without markers that could be followed for surveillance. Repeated episodes of the same infection, diagnosis of a new life-threatening infection, or specific underlying hematologic diagnoses should prompt a look for gross immunoglobulin deficiency that could be corrected in the short term by immunoglobulin therapy. At times, measurement of CD4+ lymphocyte counts will assist in determining whether augmented prophylaxis is warranted. Since their efficacy may be limited, vaccine injections are not given during the immunosuppression associated with GVHD therapy, with the exception of influenza.