Respiratory syncytial virus infection in immunocompromised adults

Respiratory syncytial virus disease was documented in 11 immunocompromised adults, aged 21 to 50. Underlying conditions included bone marrow transplant (6 patients), renal transplant (3 patients), renal and pancreas transplants (1 patient), and T-cell lymphoma (1 patient). Diagnosis of infection was based on specimens from bronchoalveolar lavage, sputum, throat, sinus aspirate, and lung biopsy. The virus was detected simultaneously by antibody in either an immunofluorescence or enzyme-linked immunosorbent assay in 3 of 4 patients whose culture results were positive for respiratory syncytial virus. The virus was an unexpected finding, despite widespread infection in the community. Clinical symptoms included low-grade fever, nonproductive cough, rhinorrhea or nasal congestion, and radiographic evidence of interstitial infiltrates and sinusitis. Aerosolized ribavirin therapy was used in the 6 recipients of bone marrow transplants, 3 of whom required assisted ventilation but died. Death caused by virus infection was documented in 4 of 11 patients. Respiratory syncytial virus disease must be considered in the differential diagnosis of fever and pulmonary infiltrates in immunocompromised adults.     

Respiratory infections in immunocompromised patients

HIV disease has been dramatically reduced in the developed world by the introduction of highly active antiretroviral therapy, with implications that prophylactic therapy against opportunistic infections may be stopped; however, tuberculosis is an escalating problem in the HIV-infected and HIV-noninfected populations worldwide. Compliance with effective treatment regimens, especially through directly observed therapy, remains the cornerstone of tuberculosis control strategies. Although tuberculosis prophylaxis is of benefit for tuberculin skin reactors with HIV in the developed world, several reservations are voiced about this approach in resource-poor settings. Recent advances in technology, particularly in antigen-specific systems, have revolutionized the understanding of HIV immunology and helped to elucidate the mechanisms of pathogenesis in diseases such as cytomegalovirus. In bone marrow transplantation and solid-organ transplantation patients, quantitative polymerase chain reaction (PCR) to predict cytomegalovirus disease is an important advance, and patients who undergo bone marrow transplantation, CT scanning has proven useful in the diagnosis of pulmonary aspergillosis.     

Respiratory syncytial virus pneumonia in four immunocompromised adults

INTRODUCTION: In hematologic malignancies, respiratory syncytial viral infections can be explained by neutropenia, and cellular and humoral immunodepression, and may cause severe respiratory infections. EXEGESIS: Four patients with hematologic malignancies developed a severe respiratory syncytial virus infection. Three of them had previously received autologous bone marrow transplantation (ABMT). Progress was favorable for three patients. One patient died of acute respiratory failure. CONCLUSION: When such patients present with respiratory symptoms, especially during the winter months, they should be screened for RSV. Bronchoalveolar lavage allowed quick and accurate diagnosis by immunofluorescence. Treatment with nebulized ribavirin is controversial. Its use may be interesting in patients with high-risk factors (intensive chemotherapy, ABMT, diffuse pneumonia with hypoxemia).     

Pulmonary cytomegalovirus infection in immunocompromised patients

BACKGROUND: Cytomegalovirus (CMV) infection and CMV disease are frequent complications in immunocompromised patients. In this study, the incidence of pulmonary CMV infection was analyzed in different groups of immunocompromised patients and the diagnostic value of immunostaining with anti-CMV antibodies in BAL cells was evaluated in regard to the diagnosis of CMV pneumonitis. METHODS: Five hundred eighty consecutive BAL procedures were analyzed prospectively in 442 immunocompromised and 126 nonimmunocompromised control subjects. CMV culture in BAL fluid was performed by shell vial assay and immunostaining using three monoclonal anti-CMV antibodies. RESULTS: The incidence of culture results positive for CMV in the BAL fluid varied from 20 to 30% in HIV-positive patients, in patients following stem cell or renal transplantation, and in patients with autoimmune disease or lung fibrosis treated with immunosuppressive agents. CMV was cultured from 4.4% of BALs in patients treated with high-dose chemotherapy and from 2.4% of control subjects. CMV disease developed in 37 patients; in 18 of these patients, CMV pneumonitis was present. The results of CMV immunostaining were positive in a total of 22 BALs, all in patients with CMV disease. The sensitivity, specificity, and positive and negative predictive values of positive CMV immunostaining results for the diagnosis of CMV pneumonitis were 88.9%, 98.6%, 72.7%, and 99.5%, respectively. CONCLUSION: The incidence of pulmonary CMV infection is similar in different groups of immunocompromised patients except for patients following high-dose chemotherapy. CMV immunostaining in the BAL fluid is a very helpful method to diagnose CMV pneumonitis in these patients.     

Respiratory syncytial virus infection

Human respiratory syncytial virus (RSV) is the most common worldwide cause of lower respiratory tract infections (LRI) in infants less than 12 months of age. RSV isolates can be divided into group A and B. In addition, there were many genotypes within each group, and these genotypes have evolved global setting with temporal and geographic clustering. Many cellular genes encoding cytokines and chemokines which are activated by RSV infection has now been focused for the elucidation of pathophysiology of RSV LRI. The prophylaxis against RSV infection by vaccination has been unsuccessful because of its adverse effects. No valuable anti-RSV drugs for clinical use have been yet developed. Therefore RSV LRI has been treated mainly symptomatically. Recently humanized anti-RSV F protein monoclonal antibody was developed and prescribed for prevention in high-risk infants such as premature ones and those with chronic lung and congenital heart diseases. It reduced the incidence of hospitalization significantly.     

Respiratory syncytial virus infection in adults

PURPOSE OF REVIEW: Respiratory syncytial virus has increasingly been recognized as a clinically significant cause of respiratory tract infections in adults, especially among the elderly and the immunocompromised. RECENT FINDINGS: Advances in molecular diagnostic methods have enabled rapid diagnosis of respiratory syncytial virus for clinical and epidemiological studies. Recent reports focus on clinical, immunological, and/or radiographic characterizations of respiratory syncytial virus infection in adults, particularly in hospitalized patients and those with underlying chronic obstructive pulmonary disease, and therapeutic and prophylactic use of antiviral agents in immunocompromised adults. Respiratory syncytial virus vaccine development remains a high priority, with the testing of genetically engineered live attenuated vaccines leading to further insights into the pathogenesis of respiratory syncytial virus in adults. SUMMARY: Further studies are necessary to elucidate the pathogenesis and immune response against respiratory syncytial virus in adults. The significant burden of respiratory syncytial virus-induced disease in adults and the limited number of approved antiviral agents reinforce the need to develop a respiratory syncytial virus vaccine.     

免疫低下患者肺部感染的特点

肺部感染是免疫低下患者死亡的主要原因,本文就免疫低下的原因和免疫低下肺部感染的发病特点、病原学特点及病原学采集技术等方面作一综述.     

Scedosporium inflatum infection in immunocompromised haematological patients

We report four cases of Scedosporium inflatum (S. inflatum) infection in severely immunocompromised haematological patients. Six well-documented cases of S. inflatum disseminated infection in haematological patients have been reported: four in Australia and two in Spain. Their clinical and pathological characteristics are heterogenous, particularly in the Australian cases. However, the clinical and pathological profile emerging from our and other Spanish cases is homogenous and very similar to the clinico-pathological spectrum of other disseminated mycoses, including Aspergillus and S. apiospermum . The optimal treatment of S. inflatum infection is unknown and the outcome in haematological patients is very poor. Eight patients died despite systemic antifungal treatment.     

Respiratory syncytial virus infection in adults

Respiratory syncytial virus (RSV), an enveloped RNA virus in the Paramyxovirus family, is the most important cause of lower respiratory tract infection in infants and young children, accounting for ~100,000 pediatric hospitalizations and 250 deaths annually in the United States. Despite primarily being recognized as a pediatric pathogen, RSV reinfection causes substantial disease in all adult populations, including healthy young persons, old and frail individuals, those with chronic obstructive pulmonary disease and immunocompromised patients. Most illnesses are mild in adults, but significant morbidity and mortality can develop. In contrast to infants, diagnosis of RSV infections is difficult due to low virus shedding, and optimal diagnosis requires molecular tests. Unfortunately, antiviral therapy is of limited benefit. Ribavirin and palivizumab are the only approved pharmacological agents for RSV treatment and prophylaxis, respectively, and are primarily used in infants; data regarding their usefulness in adults are limited. Currently, specific antiviral therapy is generally reserved for severely immunocompromised patients or severe respiratory failure. The greatest promise for reducing the impact of RSV in adults may be through immunization. However, an effective vaccine for RSV is not currently available.     

Transfusion-acquired human immunodeficiency virus infection among immunocompromised persons

Transmission of the human immunodeficiency virus (HIV) was studied in a group of patients with cancer who received transfusion of blood components harvested from a single, asymptomatic, seropositive donor. Of ten living recipients, nine had antibodies to the virus in fresh or cryopreserved sera at a median of 384 days (range, 237 to 686) after transfusion. In three patients, an enzyme-linked immunosorbent assay was negative at the same time that Western blot and radioimmunoprecipitation techniques showed seropositivity. Cultures for HIV obtained at a median of 615 days (range, 322 to 714) after transfusion were positive in seven of nine seropositive recipients. Six seropositive recipients have developed immunologic and clinical sequelae of HIV infection at a median of 286 days (range, 56 to 745) after transfusion. The sera of the two patients without clinical sequelae neutralized HIV in an in-vitro assay, whereas the seven other seropositive patients lacked such neutralizing antibodies. Our study characterizes the clinical, serologic, virologic, and immunologic manifestations of HIV infection in immunocompromised persons.     

Respiratory syncytial virus pneumonitis in immunocompromised adults: clinical features and outcome

BACKGROUND: Though predominantly an infection of children, respiratory syncytial virus (RSV) also infects adults, particularly those with immune compromise. OBJECTIVES: To define the clinical spectrum and impact of RSV pneumonitis on hospitalized, immunocompromised adults. METHODS: Retrospective chart review. Clinical parameters including premorbid conditions, presentation, radiologic findings, treatment and outcome were examined in a consecutive patients series from an inpatient tertiary-care center. Eleven immunocompromised adults who had undergone bronchoalveolar lavage (BAL) between January 1987 and December 1996 and who had culture-verified RSV pneumonitis were evaluated. RESULTS: This series consisted primarily of patients undergoing chemotherapy or bone marrow transplantation for lymphoma or leukemia. Two were immunosuppressed due to high-dose corticosteroids. A majority (91%) were admitted between November and May, with dyspnea and productive cough. In contrast to earlier studies, there was a paucity of upper respiratory infection symptoms (i.e. sinus congestion, sore throat) and a preponderance of lower respiratory physical exam findings (i.e. wheezing, bibasilar rales). Patients were typically hypoxemic and febrile prior to BAL. Eight demonstrated co-isolates of bacterial or fungi on BAL. The chest radiographs generally revealed diffuse patchy infiltrates, including alveolar opacities. Histology demonstrated diffuse alveolar damage, bronchiolitis with organizing pneumonia, and hyaline membrane formation. Over half required intubation, and 55% died. Although ribavirin therapy may be beneficial in some intubated patients, its overall efficacy cannot be established from this series. CONCLUSION: RSV is a serious cause of morbidity and mortality in immunocompromised adults. Further development and implementation of an effective vaccine and additional therapeutic interventions are needed.     

Amphotericin B-resistant yeast infection in severely immunocompromised patients

Systemic yeast infections are a major cause of morbidity and mortality in severely immunocompromised patients. The in vitro susceptibility to amphotericin B of 29 yeasts causing fungemia was examined in 26 patients undergoing allogeneic or autologous bone marrow transplantation and/or myelosuppressive chemotherapy. The minimal inhibitory concentrations (MICs) of amphotericin B observed with blood isolates from these patients were significantly higher than those observed with blood, sputum, or skin isolates from non-immunocompromised patients (p less than 0.01). All episodes (10 of 10) of bloodstream infection in immunocompromised patients caused by isolates with MICs greater than 0.8 micrograms/ml were fatal, versus eight of 17 episodes of bloodstream infection caused by yeasts with MICs of 0.8 micrograms/ml or less (p = 0.04). Although 15 of 26 patients received empiric treatment with amphotericin B before laboratory evidence of fungemia developed, the amphotericin B susceptibilities of their isolates were not significantly different from those of patients who had not received empiric amphotericin B treatment. It is concluded that yeast fungemia in severely immunocompromised patients is often caused by organisms resistant to the usual concentrations of amphotericin B obtainable in vivo, and that this finding is clinically significant.     

Clinical outcomes in outpatient respiratory syncytial virus infection in immunocompromised children

Background

Immunocompromised patients are at high risk for morbidity and mortality due to respiratory syncytial virus (RSV) infection. Increasingly, pediatric patients with malignancy or undergoing transplantation are managed primarily as outpatients. Data regarding the clinical presentation and outcomes of RSV in the outpatient pediatric immunocompromised population are limited.

Methods

We performed a retrospective cohort study of children with hematologic malignancy or hematopoietic or solid organ transplant with laboratory‐confirmed RSV infection diagnosed as outpatients at an academic medical center between 2008 and 2013.

Results

Of 54 patients with RSV detected while outpatients, 15 (28%) were hospitalized, 7 (13%) received ribavirin, and one (2%) received intravenous immunoglobulin. One (2%) patient was critically ill, but there were no deaths due to RSV infection. Fever (P < 0·01) was associated with increased risk of hospitalization.

Conclusions

Most immunocompromised children with RSV detected while outpatients did not require hospitalization or receive antiviral treatment. Potential studies of RSV therapies should consider inclusion of patients in an ambulatory setting.     

Laboratory diagnosis of cytomegalovirus infection and disease in immunocompromised patients

PURPOSE OF REVIEW: To review new developments in PCR technology as they apply to detecting cytomegalovirus viremia and pneumonia, recent advances in detecting CMV resistance to antivirals and assays of specific CMV lymphocyte function. RECENT FINDINGS: This review summarizes the attempts to use real time PCR for cytomegalovirus deoxyribonucleic acidemia and to compare it to conventional PCR and antigenemia, it also reviews the use of quantitative PCR on bronchoalveolar lavage to assist in the diagnosis of CMV pneumonia.Phenotypic assays of susceptibility in tissue culture are much too slow to assist clinical decisions, taking weeks for completion. Genotypic assays may be performed directly on clinical samples such as blood, and cerebrospinal fluid and can be done by sequencing in a very few days.Finally, assays of lymphocytic functional responsiveness to cytomegalovirus can be used to identify transplant recipients at continuing risk for cytomegalovirus disease. SUMMARY: Assays for CMV DNA or antigen in blood are superior to culture for documenting viremia and pneumonia. Genotypic assays have largely replaced phenotypic assays for CMV resistance to antivirals. Lymphocyte responses to CMV antigen(s) may identify patients at risk for CMV disease.     

Unusual pulmonary manifestations of pneumocystis carinii infection in immunocompromised patients

Three proven cases and one presumed case of Pneumocystis carinii pneumonia are presented in which the radiological appearance mimics tuberculosis. The classic and unusual X-ray findings of P. carinii pneumonia are discussed.