Low mortality rates related to respiratory virus infections after bone marrow transplantation

Impact of Influenza Infection Among Adult and Pediatric Populations With Hematologic Malignancy and Hematopoietic Stem Cell Transplant: A Systematic Review and Meta-Analysis

PURPOSE

Influenza is increasingly recognized as a leading cause of morbidity and mortality in patients with hematologic malignancies and recipients of hematopoietic stem cell transplantation (HSCT). However, the impact of influenza on this population has not been previously evaluated in a systematic review. This study systematically reviewed and summarized the outcomes of influenza infection as to in-hospital influenza-related mortality, development of lower respiratory tract infection and acute respiratory distress syndrome, need for hospitalization, intensive care unit admission, and mechanical ventilation.

METHODS

We conducted a systematic search of literature using the PubMed and EMBASE databases for articles published from January 1989 through January 19, 2020, reporting laboratory-confirmed influenza in patients of any age with hematologic malignancies and HSCT. Time from transplantation was not included in the search criteria. The impact of antiviral therapy on influenza outcomes was not assessed due to heterogeneity in antiviral treatment provision across the studies. Patients with influenza-like illness, solid-tumor cancers, or nonmalignant hematologic diseases were excluded from the study. A random-effects meta-analysis was performed to estimate the prevalences and 95% CIs of each outcome of interest. A subgroup analysis was carried out to assess possible sources of heterogeneity and to evaluate the potential impact of age on the influenza infection outcomes. Heterogeneity was assessed using the I² statistic.

FINDINGS

Data from 52 studies providing data on 1787 patients were included in this analysis. During seasonal epidemics, influenza-related in-hospital mortality was 16.60% (95% CI, 7.49%-27.7%), with a significantly higher death rate in adults compared to pediatric patients (19.55% [95% CI, 10.59%-29.97%] vs 0.96% [95% CI, 0%-6.77%]; P < 0.001). Complications from influenza, such as lower respiratory tract infection, developed in 35.44% of patients with hematologic malignancies and HSCT recipients, with a statistically significant difference between adults and children (46.14% vs 19.92%; P < 0.001). However, infection resulted in a higher hospital admission rate in pediatric patients compared to adults (61.62% vs 22.48%; P < 0.001). For the 2009 H1N1 pandemic, no statistically significant differences were found between adult and pediatric patients when comparing the rates of influenza-related in-hospital mortality, lower respiratory tract infection, and hospital admission. Similarly, no significant differences were noted in any of the outcomes of interest when comparing H1N1 pandemic with seasonal epidemics.

IMPLICATIONS

Regardless of influenza season, patients, and especially adults, with underlying hematologic malignancies and HSCT recipients with influenza are at risk for severe outcomes including lower respiratory tract infection and in-hospital mortality.

COVID-19 and hematopoietic stem cell transplantation and immune effector cell therapy: a US cancer center experience

The novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), identified in late 2019 as the causative agent of COVID-19, was declared a pandemic by the World Health Organization on 11 March 2020. Widespread community transmission in the United States triggered a nationwide shutdown, raising major challenges for administration of hematopoietic stem cell transplant (HSCT) and chimeric antigen receptor (CAR)-T cell therapies, leading many centers to delay or cancel operations. We sought to assess the impact of the COVID-19 pandemic on operations and clinical outcomes for HSCT and CAR-T cellular therapies at the Dana-Farber Cancer Institute by reviewing administration and outcomes in 127 cell therapy patients treated during the initial COVID-19 surge: 62 adult allogeneic HSCT (allo-HSCT), 38 autologous HSCT (auto-HSCT), and 27 CAR-T patients. Outcomes were compared with 66 allo-HSCT, 43 auto-HSCT, and 33 CAR-T patients treated prior to the pandemic. A second control cohort was evaluated for HSCT groups to reflect seasonal variation in infections. Although there were changes in donor selection and screening as well as cryopreservation patterns of donor products, no differences were observed across groups in 100-day overall survival, progression-free survival, rates of non-COVID-19 infections, including hospital length of stay, neutrophil engraftment, graft failure, acute graft-versus-host disease in allo-HSCT patients, or cytokine release syndrome and neurotoxicity in CAR-T patients. No HSCT patients contracted COVID-19 between days 0 and 100. One CAR-T patient contracted COVID-19 at day +51 and died of the disease. Altogether, our data indicate that cellular therapies can be safely administered throughout the ongoing COVID-19 pandemic with appropriate safeguards.

Epidemiology, Diagnosis, Treatment, and Prevention of Influenza Infection in Oncology Patients

Influenza infection causes increased morbidity and higher mortality in patients receiving treatment of underlying cancer, particularly in those with hematological malignancy or patients who have undergone hematopoietic stem-cell transplantation. The illness is characterized by seasonality and nonspecific clinical manifestations of upper respiratory infection at a time when other respiratory illnesses are common in the community, making the diagnosis challenging. However, accurate and timely diagnosis by new molecular techniques is crucial in the management of immunocompromised patients, because delays in initiating appropriate therapy can have devastating consequences. Emergence of viral resistance to currently used antiviral agents is of concern, particularly in immunocompromised hosts, and warrants continued monitoring and surveillance. Early and effective treatment improves outcomes, but optimal therapeutic strategies in patients with cancer are not well defined. Health care and research efforts should focus on defining treatment guidelines in patients with cancer and attempt to improve on current vaccination strategies.

Upper respiratory viral infections in patients with haematological malignancies after allogeneic haematopoietic stem cell transplantation: a retrospective study

BACKGROUND

Community respiratory viruses (CRVs) are associated with upper respiratory viral infections (URI), pneumonia or life-threatening respiratory disease in patients with allogeneic haematopoietic stem cell transplantation (allo-HSCT). Our aim is to demonstrate our URI experience related to CRVs after allo-HSCT.

METHODS

From January 2013 to November 2015, 39 post allo-HSCT patients with acute URI symptoms were included in the study. We evaluated CRVs by multiplex PCR from nasopharyngeal wash and throat swabs.

RESULTS

The median age of the patients was 39 (range 20-67 years). A total of 25 patients (64%) had viral panel positivity at a median 140 days post-transplant (range 3-617 days). The most common agents detected were respiratory syncytial virus (32%) and parainfluenza (32%). The patients with viral panel positivity had significantly lower lymphocyte count (1.05×10⁹/l versus 3.09×10⁹/l; P=0.013). During follow-up, 20 patients (80%) were diagnosed with pneumonia. Patients with concurrent bacterial or fungal infections were more likely to have pneumonia (100% versus 68%; P=0.023). 10 patients (40%) died due to pneumonia and related complications. Lower lymphocyte counts and higher C-reactive protein levels at the time of viral panel positivity were risk factors for mortality (1.5×10⁹/l versus 0.39×10⁹/l, P=0.007; 74.2 versus 199.7, P=0.006).

CONCLUSIONS

The viral panel was positive in 64% of patients with acute URI symptoms. Lower lymphocyte count was detected in CRV-positive patients. The onset of concomitant bacterial or fungal infections increased the risk of lower respiratory infection disease. Indeed, prospective studies should be designed for risks and outcomes of CRVs in allo-HSCT recipients.

Respiratory syncytial virus in hematopoietic cell transplant recipients and patients with hematologic malignancies

In the USA and other western nations, respiratory syncytial virus is one of the most commonly encountered respiratory viruses among patients who have been diagnosed with a hematologic malignancy or who have undergone a stem cell transplant. Multiple studies have been performed to evaluate the complications associated with respiratory syncytial virus infections. Other studies have evaluated therapeutic agents and strategies in which these agents can be used. There have also been numerous reports of outbreaks in bone marrow transplant units and oncology wards, where infection control measures have been invaluable in controlling the spread of disease. However, despite these novel approaches, respiratory syncytial virus continues to be potentially fatal in immunocompromised populations. In this review, we discuss the incidence of respiratory syncytial viral infections, risk factors associated with progression from upper respiratory tract infection to lower respiratory tract infection, other complications and outcomes (including mortality), management strategies, and prevention strategies in patients with a hematologic malignancy and in hematopoietic cell transplant recipients.

Comparative effectiveness of aerosolized versus oral ribavirin for the treatment of respiratory syncytial virus infections: A single-center retrospective cohort study and review of the literature

BACKGROUND

Respiratory syncytial virus (RSV) is a leading cause of viral infections in immunocompromised hosts and is associated with significant morbidity and mortality. In January 2015, our institution switched from aerosolized to oral ribavirin (RBV) for primary treatment of RSV infection among high-risk immunocompromised adult patients. The objective of the study was to evaluate the clinical and economic outcomes associated with this switch.

METHODS

Retrospective cohort analysis of adult patients diagnosed with RSV infection and treated with RBV between January 1, 2013, and May 31, 2016.

RESULTS

Of 46 patients, 20 (43%) patients received oral RBV and 26 (57%) received aerosolized RBV. Underlying conditions included lung transplant (n = 22), hematopoietic cell transplant (n = 16), hematological malignancy (n = 5), and structural lung diseases (n = 4). At the time of RSV diagnosis, 42 (91%) were hospitalized, 36 (78%) had clinical and radiographic evidence of lower respiratory tract infection (RTI), 9 (20%) were admitted to the ICU, and 4 (9%) required intubation. There were no differences in clinical outcomes between the 2 groups with regard to adverse events, progression from upper to lower RTI, escalation of care, or 30-day mortality. Three (15%) in the oral group and 1 (4%) in the aerosolized group died within 30 days (P = .33). The cost avoidance attributable to the switch in therapy over 1 year is $1.2 million.

CONCLUSION

Oral RBV appears to be a safe and cost-effective alternative to aerosolized RBV for the management of RSV infection in immunocompromised patients. Larger studies are needed to validate the safety and efficacy of this approach.

Influenza vaccines in immunosuppressed adults with cancer

BACKGROUND

This is an update of the Cochrane review published in 2013, Issue 10.Immunosuppressed cancer patients are at increased risk of serious influenza-related complications. Guidelines, therefore, recommend influenza vaccination for these patients. However, data on vaccine effectiveness in this population are lacking, and the value of vaccination in this population remains unclear.

OBJECTIVES

To assess the effectiveness of influenza vaccine in immunosuppressed adults with malignancies. The primary review outcome is all-cause mortality, preferably at the end of the influenza season. Influenza-like illness (ILI, a clinical definition), confirmed influenza, pneumonia, any hospitalisations, influenza-related mortality and immunogenicity were defined as secondary outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase and LILACS databases up to May 2017. We searched the following conference proceedings: ICAAC, ECCMID, IDSA (infectious disease conferences), ASH, ASBMT, EBMT (haematological), and ASCO (oncological) between the years 2006 to 2017. In addition, we scanned the references of all identified studies and pertinent reviews. We searched the websites of the manufacturers of influenza vaccine. Finally, we searched for ongoing or unpublished trials in clinical trial registry databases.

SELECTION CRITERIA

Randomised controlled trials (RCTs), prospective and retrospective cohort studies and case-control studies were considered, comparing inactivated influenza vaccines versus placebo, no vaccination or a different vaccine, in adults (16 years and over) with cancer. We considered solid malignancies treated with chemotherapy, haematological cancer patients treated or not treated with chemotherapy, cancer patients post-autologous (up to six months after transplantation) or allogeneic (at any time) haematopoietic stem cell transplantation (HSCT).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the risk of bias and extracted data from included studies adhering to Cochrane methodology. Meta-analysis could not be performed because of different outcome and denominator definitions in the included studies.

MAIN RESULTS

We identified six studies with a total of 2275 participants: five studies comparing vaccination with no vaccination, and one comparing adjuvanted vaccine with non-adjuvanted vaccine. Three studies were RCTs, one was a prospective observational cohort study and two were retrospective cohort studies.For the comparison of vaccination with no vaccination we included two RCTs and three observational studies, including 2202 participants. One study reported results in person-years while the others reported results per person. The five studies were performed between 1993 and 2015 and included adults with haematological diseases (three studies), patients following bone marrow transplantation (BMT) (two studies) and solid malignancies (three studies).One RCT and two observational studies reported all-cause mortality; the RCT showed similar mortality rates in both arms (odds ratio (OR) 1.25 (95% CI 0.43 to 3.62; 1 study, 78 participants, low-certainty evidence)); and the observational studies demonstrated a significant association between vaccine receipt and lower risk of death, adjusted hazard ratio 0.88 (95% CI 0.78 to 1; 1 study, 1577 participants, very low-certainty evidence) in one study and OR 0.42 (95% CI 0.24 to 0.75; 1 study, 806 participants, very low-certainty evidence) in the other. One RCT reported a reduction in ILI with vaccination, while no difference was observed in one observational study. Confirmed influenza rates were lower with vaccination in one RCT and the three observational studies, the difference reaching statistical significance in one. Pneumonia was observed significantly less frequently with vaccination in one observational study, but no difference was detected in another or in the RCT. One RCT showed a reduction in hospitalisations following vaccination, while an observational study found no difference. No life-threatening or persistent adverse effects from vaccination were reported. The strength of evidence was limited by the low number of included studies and by their low methodological quality and the certainty of the evidence for the mortality outcome according to GRADE was low to very low.For the comparison of adjuvanted vaccine with non-adjuvanted vaccine, we identified one RCT, including 73 patients. No differences were found for the primary and all secondary outcomes assessed. Mortality risk ratio was 0.54 (95% CI 0.05 to 5.73; low-certainty evidence) in the adjuvanted vaccine group. The quality of evidence was low due to the small sample size and the large confidence intervals for all outcomes.

AUTHORS' CONCLUSIONS

Observational data suggest lower mortality and infection-related outcomes with influenza vaccination. The strength of evidence is limited by the small number of studies and low grade of evidence. It seems that the evidence, although weak, shows that the benefits overweigh the potential risks when vaccinating adults with cancer against influenza. However, additional placebo or no-treatment controlled RCTs of influenza vaccination among adults with cancer is ethically questionable.There is no conclusive evidence regarding the use of adjuvanted versus non-adjuvanted influenza vaccine in this population.

Prevention of Infections in Patients with Hematological Malignancies

Infection is a major complication of patients with hematological malignancies. Prophylaxis is a key element in the management of these patients, and is composed by two main components: infection control measures and antimicrobial chemoprophylaxis. Infection control measures are safe, but not always effective. Antimicrobial prophylaxis is usually effective but may increase resistance rates, toxicity, and cost. Therefore, a careful evaluation of the actual risk for infection, the pathogens that predominate in a particular setting, and the periods at risk are important in order to define the most appropriate strategy. In this chapter we review the most important parameters to assess the risk on an individual basis, and the evidences and recommendations supporting infection control measures and antimicrobial prophylaxis against bacteria, fungi, viruses, and parasites.

Human Parainfluenza Virus Type 3 Infections in Patients with Hematopoietic Stem Cell Transplants: the Mode of Nosocomial Infections and Prognosis

There have been a few prospective and comprehensive surveillance studies on the respiratory viral infections (RVIs) among patients undergoing hematopoietic stem cell transplantation (HSCT). A 2-year prospective cohort surveillance study of symptomatic and asymptomatic RVIs was performed in hospitalized HSCT patients. Oropharyngeal (OP) swab samples were serially collected each week from 1 week before and up to 100 days after HSCT and were tested for virus isolation with cell culture-based viral isolation (CC-based VI) and a multiplex PCR (MPCR). A total of 2,747 OP swab samples were collected from 250 HSCT patients (268 HSCT procedures). Among these patients, 79 had RVIs (CC-based VI, n = 63; MPCR, n = 17). The parainfluenza virus type 3 (PIV3) accounted for 71% (57/80) of the cases of RVIs. Some PIV3 infections were asymptomatic and involved a longer virus-shedding period. The PIV3 was often cultured from samples taken before the onset of a respiratory disease. The PIV3 infections were attributed to the transmission of nosocomial infections. PIV3 infections before engraftment will more likely result in the development of lower respiratory tract infections and worse outcomes. A real-time monitoring of respiratory viral infections in the HSCT ward among patients with or without respiratory symptoms is required for the prevention of nosocomial RVIs, especially of PIV3 infections.

Respiratory virus infection after allogeneic hematopoietic stem cell transplant in a tropical center: Predictive value of the immunodeficiency scoring index

Background

Respiratory virus infection (RVI) is a prevalent infection in patients after allogeneic hematopoietic stem cell transplant (allo‐HSCT) and can result in significant morbidity and mortality. Ability to assess the potential severity of RVI is important in the management of such patients.

Methods

We reviewed the cases of RVI in allo‐HSCT recipients and explored the predictive value of the immunodeficiency scoring index (ISI) established for respiratory syncytial virus (RSV) and its applicability for RVI caused by other respiratory viruses.

Results

RVI occurred year‐round in our tropical transplant center, with peaks in the middle and end of the year. Ninety‐five of the 195 recipients developed a total of 191 episodes of RVI, giving a cumulative incidence of 28% by 6 months and 52% by 24 months for the first episode of RVI. RSV, influenza, rhinovirus, and parainfluenza were the most common viruses. Pneumonia occurred in 63.64%, 42.31%, and 32.42% of adenovirus, influenza, and RSV RVI episodes, respectively, but was also non‐negligible in the more benign viruses, such as coronavirus (31.58%) and rhinovirus (23.68%). Nineteen of the 63 episodes of viral pneumonia required mechanical ventilation and 14 deaths occurred within 6 weeks of the RVI. Receiver operating characteristic analysis showed that an ISI of ≥8 predicted pneumonia with a positive predictive value of >80% for RVI caused by RSV, influenza, adenovirus, and parainfluenza, while it was not predictive for coronavirus and rhinovirus.

Conclusions

The ISI is a useful aid for decision‐making during clinic consultation for patients presenting with symptoms suggestive of an RVI.

Different location, same results?

http://onlinelibrary.wiley.com/doi/10.1111/resp.13049/abstract

http://onlinelibrary.wiley.com/doi/10.1111/resp.13049/abstract

Adenovirus infection among allogeneic stem cell transplant recipients

The human adenovirus (HAdV) infection can cause severe disease in immunocompromised patients, such as those undergoing allogeneic hematopoietic stem cell transplant (ASCT). The main objective of this study was to prospectively monitor ASCT recipients for HAdV occurrence in a reference center in Brazil, and also to correlate viral positivity, viral load, molecular variant, clinical symptoms, and patients' prognosis. From October/2012 to October/2014, blood and feces of 21 ASCT recipients were screened for HAdV by Nested-PCR. Viral loads were determined by real-time PCR. In total, 57% of the patients had at least one positive sample (serum or feces) for HAdV. Patients presented significantly higher viral load in feces when compared to serum. Positive samples were characterized as HAdVs of species HAdV-C, -D, and -F. The main clinical symptom presented by infected patients was diarrhea, and Graft-versus-host disease (GVHD) was the main intercurrence. An association was observed between HAdV-positivity and diarrhea and also between HAdV-positivity and GVHD. Results from this study may contribute to a better understanding of the HAdV infection pattern in patients submitted to ASCT. Data therein highlight the importance of including HAdV testing during all routine laboratory exams performed on ASCT patients. J. Med. Virol. 89:298-303, 2017. © 2016 Wiley Periodicals, Inc.

Parainfluenza virus infections in hematopoietic cell transplant recipients and hematologic malignancy patients: A systematic review

Parainfluenza viral infections are increasingly recognized as common causes of morbidity and mortality in cancer patients, particularly in hematopoietic cell transplant (HCT) recipients and hematologic malignancy (HM) patients because of their immunocompromised status and susceptibility to lower respiratory tract infections. Advances in diagnostic methods, including polymerase chain reaction, have led to increased identification and awareness of these infections. Lack of consensus on clinically significant endpoints and the small number of patients affected in each cancer institution every year make it difficult to assess the efficacy of new or available antiviral drugs. In this systematic review, we summarized data from all published studies on parainfluenza virus infections in HM patients and HCT recipients, focusing on incidence, risk factors, long-term outcomes, mortality, prevention, and management with available or new investigational agents. Vaccines against these viruses are lacking; thus, infection control measures remain the mainstay for preventing nosocomial spread. A multi-institutional collaborative effort is recommended to standardize and validate clinical endpoints for PIV infections, which will be essential for determining efficacy of future vaccine and antiviral therapies.

Role of bronchoalveolar lavage in the diagnosis of pulmonary infiltrates in immunocompromised patients

PURPOSE OF REVIEW

To describe the role of bronchoalveolar lavage (BAL) in the evaluation of pulmonary disease in immunocompromised patients.

RECENT FINDINGS

Recent discoveries in this field are largely in two areas: the array of diagnostic testing performed on BAL fluid and technical details that can enhance the yield from this procedure. Regarding diagnostic testing, the addition of new assays, including Aspergillus galactomannan antigen assay, respiratory viral panels, and Pneumocystis jirovecii PCR, has improved the diagnostic yield of BAL over conventional cultures and stains. To improve the diagnostic yield of the procedure itself, it should be done early in the clinical course, with the BAL in the anatomic area most affected, and with a preprocedural computed tomography of the chest to properly plan the procedure.

SUMMARY

Bronchoscopic evaluation with BAL can provide important diagnostic information in immunocompromised patients with pulmonary diseases and should be routinely performed when clinically indicated and able to be completed safely.

Viral infection is not uncommon in adult patients with severe hospital-acquired pneumonia

Background

Viral pathogens have not generally been regarded as important causes of severe hospital-acquired pneumonia (HAP), except in patients with hematologic malignancy or transplant recipients. We investigated the role and distribution of viruses in adult with severe HAP who required intensive care.

Methods

From March 2010 to February 2012, adult patients with severe HAP required admission to the intensive care unit (ICU), 28-bed medical ICU in a tertiary care hospital, were prospectively enrolled. Respiratory viruses were detected using multiplex reverse-transcription polymerase chain reaction and/or shell vial culture.

Results

A total of 262 patients were enrolled and 107 patients (40.8%) underwent bronchoscopic BAL for etiologic diagnosis. One hundred and fifty-six patients (59.5%) had bacterial infections and 59 patients (22.5%) had viral infections. Viruses were detected in BAL fluid specimens of 37 patients (62.7%, 37/59). The most commonly identified viruses were respiratory syncytial virus and parainfluenza virus (both 27.1%, 16/59), followed by rhinovirus (25.4%, 15/59), and influenza virus (16.9%, 10/59). Twenty-one patients (8.0%, 21/262) had bacterial-viral coinfections and Staphylococcus aureus was the most commonly coexisting bacteria (n = 10). Viral infection in non-immunocompromised patients was not uncommon (11.1%, 16/143), although it was not as frequent as that in immunocompromised patients (36.4%, 43/119). Non-immunocompromised patients were significantly older than immunocompromised patients and had significantly higher rates of underlying chronic obstructive pulmonary disease, tuberculous destroyed lung and chronic kidney disease. The 28 day mortalities of patients with bacterial infections, viral infections and bacterial-viral coinfections were not significantly different (29.5%, 35.6% and 19.0%, respectively; p = 0.321).

Conclusions

Viral pathogens are not uncommon in adult patients with severe HAP who required ICU admission. Since viral pathogens may cause severe HAP and could be a potential source of viral transmission, further investigation is required to delineate the role of viral pathogens in severe HAP.

Antivirals for influenza: a summary of a systematic review and meta-analysis of observational studies

Despite the use of antivirals to treat patients with severe influenza, questions remain with respect to effects and safety. Although a recent systematic review has provided some indication of benefit, the analysis is limited by the quality of the available evidence from randomized controlled trials. To supplement the existing information, the authors conducted a systematic review of observational studies of antiviral treatment for influenza. This report summarises the findings of that review. Similar to the randomised trials, the confidence in the estimates of the effects for decision-making is low to very low primarily due to the risk of selection and publication bias in the observational studies. From these observational studies, the summary estimates suggest that oseltamivir may reduce mortality, hospitalisation and duration of symptoms compared with no treatment. Inhaled zanamivir may also reduce symptom duration and hospitalisations, but patients may experience more complications compared with no treatment. Earlier treatment with antivirals is generally associated with better outcomes than later treatment. Further high-quality evidence is needed to inform treatment guidelines because of the overall low to very low quality of evidence.

Secondary Acute Myeloid Leukemia in a One-Year-Old Girl Diagnosed with JAK2-V617F Mutation Positive Myeloproliferative Neoplasm

Myeloproliferative neoplasms (MPNs) are a group of clonal disorders characterized by hyperproliferation of hematologic cell lines and have been associated with tyrosine kinase JAK2-V617F mutations. Secondary acute myeloid leukemia (sAML) is a known complication of JAK2-V617F+ MPNs and bears a poor prognosis. Although the evolution of a JAK2-V617F+ MPN to a mixed-lineage leukemia has been reported in the pediatric population, no evolutions into sAML have been described. We present a case of a one-year-old girl diagnosed with JAK2-V617F+ MPN with evolution into sAML. Despite initial morphologic remission, she eventually relapsed and succumbed to her disease.

Prolonged respiratory viral shedding in transplant patients

Respiratory viral infections are frequent causes of morbidity in transplant patients. We screened symptomatic adult transplant recipients for respiratory viruses in a cohort of patients attending a referral medical center in Brazil. The duration of viral shedding and the prevalence of viral codetections were also determined. During a 1‐year period (2011–2012), swabs were obtained from 50 patients. An in‐house polymerase chain reaction panel designed to detect 10 viruses was used. Viruses were identified in 19 (38%) patients, particularly parainfluenza III (32%) and the respiratory syncytial virus (20%); multiple viruses were identified in 26% of patients. Prolonged viral shedding was observed with 60% of individuals excreting viruses for >10 days. The clinical and epidemiologic relevance of prolonged viral shedding remains to be determined.

Influenza vaccines in immunosuppressed adults with cancer

BACKGROUND

Immunosuppressed cancer patients are at increased risk of serious influenza-related complications. Guidelines, therefore, recommend influenza vaccination for these patients. However, data on vaccine effectiveness in this population is lacking, and the value of vaccination in this population remains unclear.

OBJECTIVES

To assess the effectiveness of influenza vaccine in immunosuppressed adults with malignancies. The primary review outcome is all-cause mortality, preferably at the end of the influenza season. Influenza-like illness (ILI, a clinical definition), confirmed influenza, pneumonia, any hospitalization and influenza-related mortality were defined as secondary outcomes.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and LILACS databases up to August 2013. We searched the following conference proceedings: ICAAC, ECCMID, IDSA (infectious disease conferences), ASH, ASBMT, EBMT (hematological), and ASCO (oncological) between the years 2006 to 2010. In addition, we scanned the references of all identified studies and pertinent reviews. We searched the websites of the manufacturers of influenza vaccine. Finally, we searched for ongoing or unpublished trials in clinical trial registry databases using the website.

SELECTION CRITERIA

Randomized controlled trials (RCTs), prospective and retrospective cohort studies and case-control studies were considered, comparing inactivated influenza vaccines versus placebo, no vaccination or a different vaccine, in adults (16 years and over) with cancer. We considered solid malignancies treated with chemotherapy, haematological cancer patients treated or not treated with chemotherapy, cancer patients post-autologous (up to six months after transplantation) or allogeneic (at any time) hematopoietic stem cell transplantation.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the risk of bias and extracted data from included studies adhering to Cochrane methodology. Meta-analysis could not be performed because of different outcome and denominator definitions in the included studies.

MAIN RESULTS

We identified four studies: one RCT and three observational studies, including 2124 participants. One study reported results in person-years while the other three reported per person. The studies were performed between 1993 and 2012 and included adults with haematological diseases (two studies), patients following bone marrow transplantation (one study) and solid malignancies (three studies). Only two observational studies reported all-cause mortality; one showing an adjusted hazard ratio (HR) of 0.88 (95% CI 0.77 to 0.99) for death with vaccination and the other reporting an odds ratio (OR) of 0.43 (95% CI 0.26 to 0.71). The RCT reported a statistically significant reduction in ILI with vaccination, while no difference was observed in one observational study. Confirmed influenza rates were lower with vaccination in the three observational studies, the difference reaching statistical significance in one. Pneumonia was observed significantly less frequently with vaccination in one observational study, but no difference was detected in another or in the RCT. The RCT showed a reduction in hospitalizations following vaccination, while an observational study found no difference. No life-threatening or persistent adverse effects from vaccination were reported. The strength of evidence is limited by the low number of included studies and by their low methodological quality (high risk of bias).

AUTHORS' CONCLUSIONS

Observational data suggests a lower mortality with influenza vaccination. Infection-related outcomes were lower or similar with influenza vaccination. The strength of evidence is limited by the small number of studies and by the fact that only one was a RCT. Influenza vaccination is safe and the evidence, although weak, is in favour of vaccinating adults with cancer receiving chemotherapy.

Impact of aerosolized ribavirin on mortality in 280 allogeneic haematopoietic stem cell transplant recipients with respiratory syncytial virus infections

OBJECTIVES

Respiratory syncytial virus (RSV) infections are well recognized as a significant cause of morbidity and mortality in allogeneic haematopoietic stem cell transplant (allo-HSCT) recipients. We evaluated the spectrum of clinical manifestations, management (including ribavirin-based antiviral therapy) and outcomes of RSV infections and determined the risk factors associated with RSV lower respiratory tract infection (LRTI) and all-cause mortality.

METHODS

In this retrospective study, we analysed clinical data from all laboratory-confirmed RSV infections in allo-HSCT recipients (n = 280) who presented at our institution from January 1996 to May 2009.

RESULTS

Of the 280 patients, 80 (29%) developed LRTI within 20 days (median 1 day, range 0-19 days) and 44 (16%) died within 90 days (median 26 days, range 1-82 days) from RSV diagnosis. Multivariable logistic regression analyses identified several significant risk factors associated with RSV LRTI and all-cause mortality, including age, male sex, neutropenia, lymphocytopenia and lack of ribavirin-based antiviral therapy at the upper respiratory tract infection (URTI) stage. Aerosolized ribavirin-based therapy at the URTI stage was the single most significant factor in reducing the risk of RSV LRTI (83%), all-cause mortality (57%) and RSV-associated mortality (87%) in these patients (P < 0.05), irrespective of the year of RSV diagnosis.

CONCLUSIONS

Our results demonstrate that RSV infections are a significant cause of morbidity and mortality in high-risk allo-HSCT recipients and ribavirin-based antiviral therapy at the URTI stage had a positive impact on both outcomes in this vulnerable population with multiple risk factors.

Respiratory viral infections after hematopoietic stem cell transplantation in children

This study was performed to characterize respiratory viral infections in pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). Study samples included 402 respiratory specimens obtained from 358 clinical episodes that occurred in the 116 children of the 175 consecutive HSCT cohort at Seoul National University Children's Hospital, Korea from 2007 to 2010. Multiplex reverse-transcription polymerase chain reactions were performed for rhinovirus, respiratory syncytial virus (RSV), parainfluenza viruses (PIVs), adenovirus, human coronavirus (hCoV), influenza viruses and human metapneumovirus. Viruses were identified in 89 clinical episodes that occurred in 58 patients. Among the 89 clinical episodes, frequently detected viruses were rhinovirus in 25 (28.1%), RSV in 23 (25.8%), PIV-3 in 16 (18.0%), adenovirus in 12 (13.5%), and hCoV in 10 (11.2%). Lower respiratory tract infections were diagnosed in 34 (38.2%). Neutropenia was present in 24 (27.0%) episodes and lymphopenia was in 31 (34.8%) episodes. Sixty-three percent of the clinical episodes were hospital-acquired. Three patients died of respiratory failure caused by respiratory viral infections. Respiratory viral infections in pediatric patients who have undergone HSCT are common and are frequently acquired during hospitalization. Continuous monitoring is required to determine the role of respiratory viruses in immunocompromised children and the importance of preventive strategies.

Prevention of Infections in Patients with Hematological Malignancies

Infection is a frequent complication and a leading cause of morbidity and mortality in patients with hematological malignancies. Problems associated with the management of infections in these patients include difficulties in early diagnosis because the clinical signs of infection are subtle, the low performance of diagnostic tests, and suboptimal response to treatment because recovery of host defenses is a key factor for resolution of infection. Preventing these infections relies on infection control measures and antimicrobial chemoprophylaxis. While infection control measures are safe (but not always effective), the use of antimicrobial agents for prophylaxis of infection is not devoid of problems. Its wide use may increase the possibility of the development of resistance, select for resistant organisms, and increase toxicity and cost. Therefore, any attempt to administer an antimicrobial agent should be accompanied by a reflection of the potential benefits and risks of prophylaxis.

Community-acquired respiratory viruses and co-infection among patients of Ontario sentinel practices, April 2009 to February 2010

Please cite this paper as: Peci et al. (2012) Community‐acquired respiratory viruses and co‐infection among patients of Ontario Sentinel practices, April 2009 to February 2010. Influenza and Other Respiratory Viruses 7(4), 559–566.

Background  Respiratory viruses are known to cocirculate but this has not been described in detail during an influenza pandemic.

Objectives  To describe respiratory viruses, including co‐infection and associated attributes such as age, sex or comorbidity, in patients presenting with influenza‐like illness to a community sentinel network, during the pandemic A(H1N1)pdm09 in Ontario, Canada.

Methods  Respiratory samples and epidemiologic details were collected from 1018 patients with influenza‐like illness as part of respiratory virus surveillance and a multiprovincial case–control study of influenza vaccine effectiveness.

Results  At least one virus was detected in 668 (65·6%) of 1018 samples; 512 (50·3%) had single infections and 156 (15·3%) co‐infections. Of single infections, the most common viruses were influenza A in 304 (59·4%) samples of which 275 (90·5%) were influenza A(H1N1)pdm09, and enterovirus/rhinovirus in 149 (29·1%) samples. The most common co‐infections were influenza A and respiratory syncytial virus B, and influenza A and enterovirus/rhinovirus. In multinomial logistic regression analyses adjusted for age, sex, comorbidity, and timeliness of sample collection, single infection was less often detected in the elderly and co‐infection more often in patients <30 years of age. Co‐infection, but not single infection, was more likely detected in patients who had a sample collected within 2 days of symptom onset as compared to 3–7 days.

Conclusions  Respiratory viral co‐infections are commonly detected when using molecular techniques. Early sample collection increases likelihood of detection of co‐infection. Further studies are needed to better understand the clinical significance of viral co‐infection.

An outbreak of respiratory syncytial virus infection in hematopoietic stem cell transplantation outpatients: good outcome without specific antiviral treatment

BACKGROUND

Respiratory syncytial virus (RSV) is a common cause of seasonal respiratory viral infection in hematopoietic stem cell transplantations (HSCT) patients. The efficacy of treatment, however, remains controversial. We describe an outbreak of 31 cases of RSV that occurred in an HSCT outpatient care unit in the fall season from March through May 2010, with a good outcome without any specific antiviral treatment.

METHODS

During these 3 months, 222 nasal wash samples were tested and, of these, 31 outpatients were positive for RSV. In 2009, 99 samples had been tested and only 10 outpatients were positive for RSV in the same period.

RESULTS

Seven (22.5%) patients had severe neutropenia (<500 cells/μL); severe lymphopenia (<200 cells/μL) was present in 13 (41.9%) patients, and 14 (45%) had received intravenous broad-spectrum antibiotics. Hospitalization was necessary only for 8 patients (25.8%); 20 had lower respiratory tract infection (64.5%). Only 1 patient died as a result of proven invasive aspergillosis.

CONCLUSION

This report suggests that HSCT outpatients with no risk factors may not always require specific treatment for RSV.

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.

Antivirals for treatment of influenza: a systematic review and meta-analysis of observational studies

BACKGROUND

Systematic reviews of randomized, controlled trials in patients with influenza suggest a lack of evidence about the effects of antiviral therapy on several patient-important outcomes of influenza.

PURPOSE

To systematically review observational studies for benefits and harms of oseltamivir, zanamivir, amantadine, or rimantadine in the treatment of influenza.

DATA SOURCES

MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, CINAHL, SIGLE, the Chinese Biomedical Literature Database, Panteleimon, and LILACS up to November 2010; contact with pharmaceutical companies; and reference lists.

STUDY SELECTION

Observational studies in any language that compared single antiviral therapy with no therapy or other antiviral therapy, or that had no comparator, for influenza or influenza-like illness.

DATA EXTRACTION

Two independent investigators extracted data. Confidence in the estimates of the obtained effects (quality of evidence) was assessed by using the Grading of Recommendations Assessment, Development, and Evaluation approach.

DATA SYNTHESIS

74 studies fulfilled the inclusion criteria. Meta-analyses of the few studies providing effects with adjustment for confounders suggest that, in high-risk populations, oral oseltamivir may reduce mortality (odds ratio, 0.23 [95% CI, 0.13 to 0.43]; low-quality evidence), hospitalization (odds ratio, 0.75 [CI, 0.66 to 0.89]; low-quality evidence), and duration of symptoms (33 hours [CI, 21 to 45 hours]; very low-quality evidence) compared with no treatment. Earlier treatment with oseltamivir was generally associated with better outcomes. Inhaled zanamivir may lead to shorter symptom duration (23 hours [CI, 17 to 28 hours]; moderate-quality evidence) and fewer hospitalizations (odds ratio, 0.66 [CI, 0.37 to 1.18]) but more complications than no treatment. Direct comparison of oral oseltamivir and inhaled zanamivir suggests no important differences in key outcomes. Data from 1 study suggest that oral amantadine may reduce mortality and pneumonia associated with influenza A. No included study evaluated rimantadine.

LIMITATIONS

Mortality was assessed in high-risk patients, and generalizability is limited. The overall body of evidence is limited by risk for confounding and selection, reporting, and publication bias.

CONCLUSION

Therapy with oral oseltamivir and inhaled zanamivir may provide a net benefit over no treatment of influenza. However, as with the randomized trials, the confidence in the estimates of the effects for decision making is low to very low. PRIMARY FUNDING SOURCES: World Health Organization and McMaster University.

Prophylaxis and treatment of respiratory syncytial virus in adult immunocompromised patients

OBJECTIVE

To review the literature regarding current strategies and strategies under active development for the prevention and treatment of respiratory syncytial virus (RSV) infections in immunocompromised adults.

DATA SOURCES

The MEDLINE/PubMed, EMBASE, and Cochrane databases were queried from January 1980 to December 2011 for articles in English using these associated search terms: respiratory syncytial virus, ribavirin, intravenous immunoglobulin, IVIG, palivizumab, motavizumab, lung, pneumonia, transplantation, bone marrow, cancer, malignancy, and vaccine.

STUDY SELECTION AND DATA EXTRACTION

All relevant original studies, meta-analyses, systematic reviews, and review articles were assessed for inclusion. References from pertinent articles were examined for additional content not found during the initial search.

DATA SYNTHESIS

RSV in the immunocompromised adult can lead to significant morbidity and mortality. Treatment of RSV-infected adults is limited to antiviral therapy with ribavirin (aerosolized, oral, intravenous) and immunomodulation with intravenous immunoglobulins, corticosteroids, and palivizumab. Existing literature is predominantly case reports, small trials, and retrospective reviews of patients infected with RSV who have undergone lung or hematopoietic stem cell transplantation (HSCT). Palivizumab may be a viable option for prophylaxis against RSV in high-risk adults. Ribavirin is the most studied treatment option and should remain the backbone of multidrug regimens. Of the routes of administration, aerosolized ribavirin carries the preponderance of evidence and, though challenging, is preferred to limit systemic toxicities in the infected patient. Addition of an immunomodulator to ribavirin may provide a survival benefit over ribavirin alone; however, this has only been studied in a subset of HSCT patients with lower respiratory tract RSV infection.

CONCLUSIONS

Research most strongly supports the use of aerosolized ribavirin as the treatment strategy for immunocompromised adults with RSV. Addition of an immunomodulator may provide a survival benefit over ribavirin alone. Strategies and supportive data for the prevention of RSV infection in the high-risk adult are critically needed.

Fighting misconceptions to improve compliance with influenza vaccination among health care workers: an educational project

The compliance with influenza vaccination is poor among health care workers (HCWs) due to misconceptions about safety and effectiveness of influenza vaccine. We proposed an educational prospective study to demonstrate to HCWs that influenza vaccine is safe and that other respiratory viruses (RV) are the cause of respiratory symptoms in the months following influenza vaccination. 398 HCWs were surveyed for adverse events (AE) occurring within 48 h of vaccination. AE were reported by 30% of the HCWs. No severe AE was observed. A subset of 337 HCWs was followed up during four months, twice a week, for the detection of respiratory symptoms. RV was diagnosed by direct immunofluorescent assay (DFA) and real time PCR in symptomatic HCWs. Influenza A was detected in five episodes of respiratory symptoms (5.3%) and other RV in 26 (27.9%) episodes. The incidence density of influenza and other RV was 4.3 and 10.8 episodes per 100 HCW-month, respectively. The educational nature of the present study may persuade HCWs to develop a more positive attitude to influenza vaccination.

Clinical evaluation of multiplex real-time PCR panels for rapid detection of respiratory viral infections

Respiratory viral infections are one of the leading causes of morbidity and mortality, particularly in children, the elderly and immunocompromised persons. Rapid identification of viral etiology is critical in ruling out non‐viral infections, initiating antiviral treatment and limiting the spread of the infection. Multiplex assays of more than one viral gene target in a single tube have the advantage of rapid screening of a large number of potential viral pathogens in a short time. A multiplex real‐time PCR assay was used in this study for detection of respiratory RNA and DNA viral infections in 728 specimens received from 585 adult and pediatric patients comprised of symptomatic and asymptomatic organ transplant recipients and non‐recipients for diagnosis of respiratory illnesses and for routine clinical monitoring. Multiplex PCR was more sensitive than the multiplex immunofluoresence culture assay (R‐mix) and also detected additional respiratory viruses that were not covered by the R‐mix panel. The number of respiratory viruses detected in symptomatic patients was significantly higher than asymptomatic patients in both adult and pediatric patients. Herpesviral infections were the predominant cause of lower respiratory tract infection in the organ transplant recipients, whereas respiratory syncytial virus was the most common pathogen in non‐transplant patients particularly children. Multiplex real‐time PCR for detection of respiratory viruses has the potential for rapid identification of viral pathogens. In this era of emerging viral infections, addition of newer viral targets to the multiplex PCR panels will be beneficial in determining both patient management and public health epidemiology. J. Med. Virol. 84:162–169, 2011. © 2011 Wiley Periodicals, Inc.

Changing epidemiology of respiratory viral infections in hematopoietic cell transplant recipients and solid organ transplant recipients

PURPOSE OF REVIEW

New respiratory viruses have been discovered in recent years and new molecular diagnostic assays have been developed that improve our understanding of respiratory virus infections. This article will review the changing epidemiology of these viruses after hematopoietic stem cell and solid organ transplantation.

RECENT FINDINGS

Respiratory viruses are frequently detected in transplant recipients. A number of viruses have been newly discovered or emerged in the last decade, including human metapneumovirus, human bocavirus, new human coronaviruses and rhinoviruses, human polyomaviruses, and a new 2009 pandemic strain of influenza A/H1N1. The potential for these viruses to cause lower respiratory tract infections after transplantation varies, and is greatest for human metapneumovirus and H1N1 influenza, but appears to be limited for the other new viruses. Acute and long-term complications in hematopoietic and solid organ transplant recipients are active areas of research.

SUMMARY

Respiratory viral infections are frequently associated with significant morbidity following transplantation and are therefore of great clinical and epidemiologic interest. As new viruses are discovered, and more sensitive diagnostic methods are developed, defining the full impact of emerging respiratory viruses in transplant recipients must be elucidated by well designed clinical studies.

Novel influenza a (H1N1) infection in a Pediatric Hematology Oncology Clinic during the 2009-2010 pandemia

Pandemic influenza A infection (2009 H1N1) was associated with a worldwide outbreak of febrile respiratory infection. Although usually it results in a mild illness, certain patient groups are at increased risk for complications. The authors reviewed their experience in a pediatric hematology-oncology unit to determine the outcome of this disease in children with hematological conditions and solid tumors. During the second outbreak (1 November 2009 to 14 January 2010), a total of 187 children from pediatric clinic were tested for H1N1 influenza A by multiplex polymerase chain reaction (PCR), 63 of them were positive. Patients' signs and symptoms were recorded prospectively. Ten (35.7%) (5 children with solid tumors, 4 with leukemia, 1 with hereditary spherocytosis) of 28 tested children with hematological conditions were diagnosed with 2009 H1N1 influenza infection. Fever (100%) and cough (90%) were the most common symptoms. Five were neutropenic (neutrophil count <1000/mm(3)), 4 had severe neutropenia (neutrophil count <500/mm(3)). Systemic antibiotics were given in 5 patients with the diagnosis of febrile neutropenia. Four were inpatients, others were hospitalized after the diagnosis. One patient required mechanical ventilation; however, he had concomitant invasive fungal infection. Eight patients were treated by oseltamivir, all tolerated the drug well. A total of 4 cases from 9 cancer patients had a delay in their planned chemotherapy for 7 to 15 days. Pandemic H1N1 influenza caused mild symptoms in children with cancer and/or hematological conditions but resulted in delay in anticancer therapy and increase in hospitalization and antibiotic usage.

Evaluation of a clinical scoring system and directed laboratory testing for respiratory virus infection in hematopoietic stem cell transplant recipients

P.E. Ferguson, N.M. Gilroy, T.P. Sloots, M.D. Nissen, D.E. Dwyer, T.C. Sorrell. Evaluation of a clinical scoring system and directed laboratory testing for respiratory virus infection in hematopoietic stem cell transplant recipients.
Transpl Infect Dis 2011: 13: 448–455. xx: 000–000. All rights reserved

Abstract: A simple clinical screening (CS) tool for respiratory virus (RV) infection was introduced and evaluated in a single hematology ward, as part of a strategy to reduce nosocomial RV infection. Up to 6 clinical symptoms or signs were scored and a predefined threshold score of ≥2 prompted paired nose/throat swab (NTS) collection for RV testing. The criterion standard for RV infection was positive immunofluorescence (IF) or polymerase chain reaction (PCR) for 7 and 15 viruses, respectively. The tool was shown to be most beneficial at excluding infection at a threshold score of 1 (negative predictive value [NPV] 89%, [95% confidence interval 78–96%], sensitivity 85% [70–94%], specificity 35% [27–43%]), compared with a score of 2 (NPV 85% [76–91%], sensitivity 63% [46–77%], specificity 57% [48–65%]) at a prevalence of 22%. The tool's ability to diagnose infection was limited (positive predictive value 27% and 29% at thresholds 1 and 2). The sensitivity of IF compared with PCR was 45% for the 7 viruses common to both, and 23% for the extended virus panel detected by PCR. An algorithm incorporating CS, paired NTS collection at a threshold of 1 symptom or sign, and sensitive testing including PCR can guide infection control measures in hospitalized hematopoietic stem cell transplant recipients.

Management of RSV infections in adult recipients of hematopoietic stem cell transplantation

Respiratory syncytial virus (RSV) is a common cause of seasonal respiratory viral infection in patients who have undergone hematopoietic stem cell transplantation. RSV usually presents as an upper respiratory tract infection in this patient population but may progress rapidly to lower respiratory tract infection. Available therapies that have been used for the treatment of RSV infections are limited to ribavirin, intravenous immunoglobulin, and palivizumab. The use of aerosolized ribavirin, alone or in combination with either palivizumab or intravenous immunoglobulin, remains controversial. In this comprehensive review, we present and discuss the available literature on management of RSV infections in adult hematopoietic stem cell transplantation recipients with a focus on therapeutic modalities and outcomes.

The clinical features and outcome of 2009 H1N1 influenza infection in allo-SCT patients: a British Society of Blood and Marrow Transplantation study

The clinical course of 2009 H1N1 influenza in Allo-SCT patients is unknown. Data were collected in the UK from October 2009 to April 2010 on laboratory-confirmed cases of H1N1 influenza in Allo-SCT recipients. H1N1 infection was diagnosed in 60 patients, median age 42 years, at a median of 10 months post-SCT. Twenty-one patients (35%) developed pneumonia and nine (15%) required admission to intensive care units. Actuarial mortality was 7% at 28 days and 19% 4 months post-diagnosis of 2009 H1N1 influenza. Increasing age and pre-existing lung disease were risk factors for pneumonia (P=0.006 and 0.037, respectively); older age was a risk factor for death (P=0.012). Morbidity and mortality from 2009 H1N1 influenza in SCT patients exceeds that of immunocompetent patients, but parallels that in other critically ill hospitalised cohorts; the elderly and those with chronic pulmonary disease are at greatest risk.

Common Viral Pneumonia

Common respiratory viruses are now recognised as true opportunistic respiratory pathogens in patients with haematological malignancies. The epidemiology of these viruses has not been extensively studied in immunocompromised hosts, but is probably closely related to viral activity in immunocompetent hosts, who constitute the virus reservoir for immunocompromised patients. In these patients, common respiratory viruses may cause severe infections with higher rates of progression to pneumonia and mortality compared to immunocompetent individuals. Prolonged high-titre viral shedding is common in patients with haematological malignancies and may enhance not only viral transmission, but also the selection of resistant strains. Influenza and respiratory syncytial virus (RSV) infections have been particularly well studied. They are associated with pneumonia rates of about one-third for influenza and 30–40% for RSV. Both viruses are responsible for mortality rates ranging from 15% to 30%. The exact mechanisms of pneumonia related to these viruses remains unknown, but bacterial and fungal co-infections are frequent and must be carefully investigated. Parainfluenza viruses (PIV) and RSV have also been linked to late airflow obstruction in haematopoietic stem cell transplant recipients. Neuraminidase inhibitor therapy has been suggested for influenza, ribavirin for RSV, and cidofovir for adenovirus infections. However, there is no evidence supporting the use of these drugs, and randomised controlled trials are urgently needed to better define the optimal management of common viral pneumonia in patients with haematological malignancies. The absence of proven effective treatments highlights the critical importance of prevention. Viral transmission may be interrupted by contact isolation with droplet precautions for infected patients and by having patients and health care workers with suspected infection, and their relatives, refrain from visits and work. Immunisation remains the cornerstone of influenza prevention and is recommended for patients with haematological malignancies, their relatives, and health care workers.

[Children with cancer and respiratory viral infection: epidemiology, diagnosis and treatment options]

Community-adquired respiratory viral infection is the most common cause of febrile infection in children, and an important cause of infection to consider in children with cancer. Nevertheless, there are few well-designed, controlled studies in this population, which makes it difficult to understand the importance, behaviour and management of these viruses in immunocompromised children. New diagnostic techniques in PCR-based microbiology, could provide many opportunities for early diagnosis, preventing the spread of the virus and to implement the correct therapy. It is important to design appropriate prospective studies to assess these types of infections in children with cancer. In this review we analyse the main studies published in the literature, evaluating the epidemiology, diagnosis and management of children with cancer and respiratory viral infection.

Influenza, including the novel H1N1, in organ transplant patients

PURPOSE OF REVIEW

This article will review the epidemiology, diagnosis, prevention and management of influenza in solid organ transplant recipients.

RECENT FINDINGS

A number of recent studies have documented that influenza vaccination is both well tolerated and generally effective in producing an immunologic response in most solid organ transplant (SOT) recipients. Antiviral use is associated with improved clinical outcomes, but prolonged shedding may require a longer course of therapy than what is currently approved by the FDA. Antiviral resistance emerges rarely in transplant patients and should be considered in all patients with an inadequate clinical and/or virologic response.

SUMMARY

Influenza is associated with significant morbidity and mortality, particularly in lung transplant recipients. Molecular diagnostics are preferred over other diagnostic modalities, if available. Influenza vaccination is well tolerated and provides protective benefit in most SOT recipients; in those with contraindications to vaccination or in whom responses are predicted to be poor, antivirals may be considered. Antiviral therapy is associated with improved outcomes in transplant patients and treatment should be continued until clinically and virologic response have been documented. Resistance, particularly with patients infected with the pandemic influenza A/H1N1, should be considered and treated with an antiviral with predicted activity.

Viral pneumonias in immunocompromised adult hosts

Viral infections have always been considered pediatric diseases. However, viral pneumonia has become an important cause of morbidity and mortality in immuncompromised adults. Improved diagnostic techniques, such as the introduction of highly sensitive nucleic acid amplification tests, have not only allowed us to discover new viruses but also to determine the etiology of viral pneumonia in immunocompromised adult hosts. Unfortunately, only a few antiviral agents are available. Thus, early diagnosis and treatment are crucial to patient outcome. In this article, we review the most common viruses that have been implicated as etiologic agents of viral pneumonia in immunocompromised adults. We discuss the epidemiologic characteristics and clinical presentation of these viral infections and the most appropriate diagnostic approaches and therapies when available.

Successful prevention of respiratory syncytial virus nosocomial transmission following an enhanced seasonal infection control program

Respiratory syncytial virus (RSV) infections can be serious in severely immunocompromised patients. Use of a targeted infection control program (TICP) has been shown to reduce RSV nosocomial transmission. We evaluated the impact of an enhanced seasonal infection control program (ESICP) vs standard TICP in a hematology-oncology ward. TICP was applied from 1999 to 2001 and ESICP applied from 2001 to 2003. ESICP consisted of strict isolation for all patients admitted on the ward during the RSV season. We prospectively evaluated the incidence, related morbidity and mortality of nosocomial RSV in both field interventions. A total of 40 hospitalized RSV infections were documented. The cumulative incidence of nosocomial RSV during TICP and ESICP was respectively of 42.8 and 3.9 cases/1000 admissions (relative risk = 0.09). ESICP needed to be implemented on 26 admitted patients on our ward to prevent one RSV nosocomial case. Furthermore, implementation of ESICP prevented four pneumonias and two deaths per RSV season. We conclude that ESICP is significantly more efficient than TICP to reduce the occurrence of nosocomial RSV infections and its related morbidity and mortality in patients with hematological malignancy and recipients of hematopoietic SCT.

Successful treatment of influenza A virus by oseltamivir in bone marrow transplant recipients

INFVA is an important cause of pulmonary infections in patients receiving BMT, and is associated with considerable morbidity and mortality for a readily preventable and treatable infection. Few studies have addressed the impact of the new neuraminidase inhibitors in the prognosis of influenza after BMT. The aim of this study is to assess the impact of oseltamivir on the control of INFVA infection in BMT recipients. INFVA was screened in NPA and/or bronchoalveolar lavage using IF in all BMT recipients having respiratory symptoms. Three URTI and one associated upper and LRTI were diagnosed in three BMT recipients out of six patients admitted to the BMT unit, during eight-wk period (March and April 2008). All patients having INFVA respiratory infection were treated by oral oseltamivir 60 mg/day, begun more than 48 h after symptom onset. Respiratory symptoms disappeared within a mean of 60 h (48-96 h) of treatment. However, viral tests had remained positive for 8-39 days. Outside the initial associated URTI and LRTI, no further viral pneumonia occurred. No patient died of INFVA. Oseltamivir was well tolerated outside vomiting during the first three days of treatment in one patient. Oseltamivir appears to play an important role in the outcome of INFVA infection as well in URTI as in severe LRTI in patients receiving BMT.

Risk factors for pneumonia in immunocompromised patients with influenza

BACKGROUND

Immunocompromised patients with influenza are at higher risk of pneumonia and death. However, risk factors for progression to pneumonia still need evaluation.

METHODS

Retrospective study in immunocompromised patients with influenza-related respiratory infections. Risk factors for pneumonia were identified by multivariable logistic regression.

RESULTS

We identified 100 immunocompromised patients infected with influenza (68 hematological malignancies, 11 HIV, 21 iatrogenic immunosuppression). Immunofluorescence was positive in 95% of patients, mainly on nasopharyngeal aspirates (84%). Influenza A virus was involved in 80% of patients. Associated infection was documented in 34 patients. All patients presented with upper respiratory tract infection and 53 progressed to pneumonia. Thirty-two patients were critically ill, 11 received mechanical ventilation, and 10 died. All the patients who died had pneumonia. Patients with pneumonia were older (46y (36-63) vs. 33y (13-51), P=0.003) and more often had influenza A (89% vs. 70%, P=0.04) and associated infection (56% vs. 9%, P<0.0001). Factors independently associated with progression to pneumonia were influenza A (OR 5.54, 95% CI [1.16-26.47]) and hematological malignancies (OR 3.85, 95% CI [1.1-14.5]).

CONCLUSIONS

In our cohort of hospitalized immunocompromised patients, influenza progresses to pneumonia in more than half the patients. Patients with hematological malignancies and influenza A infection are at higher risk for pneumonia and should be included in preemptive antiviral therapy trials.