What role for human rhinoviruses in the lower respiratory tract?

Human rhinoviruses (HRV) usually cause upper airway infections. However, viral replication in the tracheobronchial tree has been disclosed, although its clinical role is poorly known. We evaluated the prevalence of HRV in 159 bronchoalveolar lavages from 88 patients and describe a lung transplant recipient with a high HRV load in association with acute rejection. HRV was detected in 22/88 patients (25.0%): 7/18 lung transplant recipients, 11/41 immunocompetent, and 4/29 immunocompromised (p = n.s.). No lung disease was significantly associated with HRV positivity. It should be recommended to include HRV in the virological diagnostic work-up of lower respiratory specimens to elucidate their role.

Development of a RT real-time PCR for the detection and quantification of human rhinoviruses.

Human Rhinoviruses (HRV) are the most common viral agents, being responsible for upper as well as lower respiratory tract infections. Evidence demonstrating that HRV disease is not exclusively limited to the upper airways and may cause lower respiratory complications, together with the frequency of HRV infections and the increasing number of immunocompromised patients underline the need for including HRV in virological diagnostics of acute lower respiratory tract illness. This article describes the development and optimization of a reverse transcription (RT) real-time PCR assay for quantification of HRV RNA in clinical samples. Efficiency, sensitivity, specificity, inter- and intra-assay variability, and dynamic range have been determined. Subsequently, the assay has been validated on bronchoalveolar lavage (BAL) specimens obtained from immunocompetent and immunocompromised patients.

Quantitative detection of Epstein-Barr virus in bronchoalveolar lavage from transplant and nontransplant patients.

BACKGROUND: The lower respiratory tract is a latency site of Epstein-Barr virus (EBV); however, its pathogenic role is poorly known, particularly in transplant patients. The aim of this study was to evaluate the prevalence and role of EBV in bronchoalveolar lavages (BAL) from transplant recipients (TR) in comparison with nontransplant (NT) patients. METHODS: Real-time quantitative polymerase chain reaction for EBV, human herpesvirus-6 (HHV-6), and HHV-7 and rapid shell-vial culture for human cytomegalovirus (HCMV) were performed on 272 consecutive BAL from 194 patients (107 from 59 TR and 165 from 143 NT). RESULTS: EBV-DNA was positive in 65 specimens (23.9%) from 57 patients (29.4%): 24 of 59 (40.7%) TR and 33 of 143 (23.1%) NT (P<0.05). There was no significant difference of EBV positivity considering the type of transplanted organ. Viral load did not significantly differ comparing specimens of TR versus NT, specimens of solid organ transplant versus bone marrow transplant recipients. EBV was frequently positive in patients with a diagnosis of pneumonia (28.6%), respiratory insufficiency (24.5%), and exacerbation of underlying bronchopneumopathies (30.8%); however, there was no difference comparing TR and NT. EBV was mostly detected in concomitance with other infectious pathogens. Mortality within 28 days of BAL sampling was not related to EBV-DNA positivity and load. CONCLUSIONS: EBV is frequently detected in BAL from TR and NT; however, its pathogenic role in lower respiratory tract remains poorly known, also because of the frequent detection of concomitant infectious pathogens. Further studies are needed to better elucidate this issue and the underlying local conditions favoring viral replication.

Decrease of specific and total IgE levels in allergic patients after BCG vaccination: preliminary report.

BACKGROUND: A systemic reaction to mycobacteria biases the balance of T helper cell types 1 and 2 toward T helper cell type 1. BCG vaccination mimics some characteristics of mycobacterial infection. Children who have undergone tuberculin conversion after BCG vaccination seem to be more likely to lose their atopic symptoms. Inhibition of both allergic response and airway hyperreactivity after vaccination for mycobacteria has been observed in animal experiments. OBJECTIVE: To evaluate the effects that BCG vaccination has on the serological status of allergic people. PARTICIPANTS AND METHODS: This study included 20 volunteers with a history of allergic rhinitis who were required to undergo BCG vaccination by Italian law. Epicutaneous allergy testing with a panel of common seasonal and perennial inhalational allergens and 2 blood withdrawals were performed. The serum total IgE levels and the serum allergen-specific IgE levels of each individual were measured just before BCG vaccination and again 4 months later. Total IgE levels were determined using the paper radioimmunosorbent test, and allergen-specific IgE levels were determined using the radioallergosorbent test. RESULTS: Total IgE and allergen-specific IgE levels were significantly decreased after BCG vaccination (P =.004 and P<.001, respectively). CONCLUSION: BCG, an effective stimulus for cell-mediated immunity, deserves further study to evaluate its ability to modulate the immune response associated with allergic rhinitis.