Cytomegalovirus (CMV) reactivation occurs frequently in critically ill patients. The natural course of CMV infection and the interaction between CMV and the adaptive immune system in this setting remain poorly defined. Fifty‐three CMV‐seropositive patients in a surgical and trauma intensive care unit were included in this study. The CMV DNA load in tracheal aspirates (TA) and plasma (PL) was monitored by qPCR. CMV‐specific T‐cell immunity was assessed by intracellular cytokine staining. Plasma TNF‐α levels were determined by ELISA. CMV reactivation occurred in 39.7% of patients (23% had CMV DNA detected only in TA). The analysis of TA allowed an earlier diagnosis in 28% of patients. Clearance of CMV DNAemia preceded that of CMV DNA in TA in some episodes. Peak CMV DNA levels were significantly higher in TA than in PL (P = 0.02). CMV reactivation developed in the presence of CMV‐specific T cells. Termination of CMV reactivation was associated with an expansion of functional CMV‐specific T cells. Plasma levels of TNF‐α did not allow for the prediction of the occurrence of CMV reactivation. CMV‐specific T‐cell immunity is preserved in most critically ill patients experiencing CMV reactivation. Analysis of respiratory specimens is imperative for an optimal monitoring of CMV reactivation in this setting. J. Med. Virol. 82:1384–1391, 2010. © 2010 Wiley‐Liss, Inc.

The dynamics of CMV pp65 and IE-1-specific IFNgamma-producing CD8(+) (IFNgamma CD8(+)) and CD4(+) (IFNgamma CD4(+)) T cells and CMV DNAemia were assessed in 19 pre-emptively treated episodes of active CMV infection. Peripheral counts of IFNgamma CD8(+) and IFNgamma CD4(+) T cells inversely correlated with CMV DNAemia levels (P = <0.001 and P = 0.003, respectively). A threshold value of 1.3 cells/microl predicting CMV DNAemia clearance was established for IFNgamma CD8(+) T cells (PPV, 100%; NPV, 93%) and for IFNgamma CD4(+) T cells (PPV, 100%; NPV, 75%). Undetectable T-cell responses were usually observed at the time of initiation of pre-emptive therapy. Either a rapid (within 7 days) or a delayed (median 31 days) expansion of both T-cell populations concomitant with CMV DNAemia clearance was observed in 5 and 8 episodes, respectively. An inconsistent or a lack of expansion of both T-cell subsets was related to a persistent CMV DNAemia. Robust and maintained CMV-specific T-cell responses after CMV DNAemia clearance and cessation of antiviral therapy were associated with a null incidence of relapsing infections at least during the following month. Data obtained in the present study may be helpful in the design of therapeutic strategies for the management of active CMV infections in the allo-SCT recipient.

Dissociation of cytomegalovirus (CMV) DNA loads between the lower respiratory tract and blood, with high levels in the former compartment and low or undetectable levels in the latter, commonly occurs during active CMV infection in critically ill patients despite the presence of high frequencies of CMV-specific IFN-γ-producing CD8(+) and CD4(+) T cells in blood. Data presented in this case report suggest that inter-compartmental differences in interleukin-10 (IL-10) levels may, in part, explain the pathobiology of this phenomenon. In the absence of ganciclovir treatment, a significant correlation was observed between IL-10 levels and CMV DNA loads in lower respiratory tract specimens (P = 0.016), but not in plasma samples (P = 0.46). Comparable data were obtained during the course of active CMV infection episodes that developed in six CMV-seropositive critically ill patients with no canonical immunosuppression. The presence of higher levels of IL-10 in the lower respiratory tract than in plasma may result in increased impairment of CMV-specific T-cell effector responses in the lung compared to the systemic compartment, facilitating local CMV replication.

ᰔPositive galactomannan antigen (GM) test results with serum by the Platelia Aspergillus assay (Bio-Rad, Marnes-LaCoquette, France) have been reported to occur during invasive fungal infections caused by Penicillium marneffei (8), Cryptococcus neoformans (2), Geotrichum capitatum (3), or Histoplasma capsulatum (1,6, 11). We report on a case of a positive GM result in bronchoalveolar lavage fluid (BAL fluid) in the clinical setting of a possibly invasive infection caused by Lichtheimia ramosa. The patient was a 10-year-old girl with acute myeloblastic leukemia in second relapse who presented with fever (101°F), cough, and dyspnea. A chest X ray showed diffuse reticular changes, and a blood count revealed severe neutropenia (200 leukocytes/l). The patient began empirical treatment with ceftazidime and amikacin. Vancomycin was later added on the basis of Gram stain results from a positive blood culture. A computed tomography (CT) scan was performed 48 h after admission. A nodular lesion in the right upper lobe compatible with invasive aspergillosis was observed. Voriconazole therapy was then initiated. Worsening of the patient's clinical condition prompted the addition of meropenem and caspofungin to the antibiotic regimen. Fiberoptic bronchoscopy was performed (14 days after admission), and BAL fluid in saline solution was submitted to the Microbiology Service for microscopic examination, culture, and GM testing. Nonseptate hyphae with irregular branching were seen by calcofluor white staining of a direct smear. Lichtheimia ramosa (deposited in the Spanish Type Culture Collection) was isolated on Sabouraud glucose medium within 48 h of plating. Microbial identification was confirmed by direct sequencing of the internal transcribed spacer 2 (ITS2) region of the ribosomal DNA gene (9). The antifungal susceptibility profile as determined by a conventional microdilution method was as follows: the isolate was susceptible to amphotericin B (0.25 g/ml) and posaconazole (0.5 g/ml) and resistant to the echinocandins (Ͼ8 g/ml). The BAL fluid (two different aliquots) tested positive by the GM assay (index value, 2.9). The positive results were reproduced in a second analysis of samples. Aspergillus species DNA was not detected in BAL fluid by realtime PCR (FXG:RESP Asp ϩ test kit and Cepheid SmartCycler; Myconostica Ltd., Manchester, United Kingdom). The patient was admitted to the intensive care unit and died shortly thereafter. Serial serum samples obtained at hospital admission until 16 h prior to death (n ϭ 3) tested negative by the GM assay (index values of 0.103, 0.104, and 0.107).A mycelial extract antigen from the isolated organism was prepared (4) and tested at a 1:100 dilution in phosphate-buffered saline by the GM assay, yielding a positive result (index value, 1.23). Extracellular polysaccharide antigens produced by Zygomycetes, such as Rhizopus oryzae, Lichtheimia corymbifera, and Cunninghamella bertholletiae (but not by Lichtheimia ramosa), have been shown previously to test negative (index values Յ 0.5) in the...

Cytomegalovirus (CMV) may be a relevant cause of morbidity in patients displaying various inflammatory diseases. In this study, it was investigated whether CMV DNA is detected in the lower respiratory tract and the systemic compartment in pediatric patients with chronic or recurrent bronchopulmonary diseases. A total of 42 lower respiratory tract specimens and 11 paired plasma samples from 42 patients were analyzed for the presence of CMV DNA by real-time PCR. The respiratory specimens were also screened for the presence of respiratory viruses and human herpesvirus 6 (HHV-6) and 7 (HHV-7) by PCR methods. Quantitative bacterial and fungal cultures were performed. IL-6 levels in the respiratory specimens were quantified using ELISA. CMV DNA was detected either in the lower respiratory airways, in plasma, or both in 54.5% of CMV-seropositive patients. The levels of IL-6 were significantly higher in these patients than in those with no detectable levels of CMV DNA. HHV-6 and HHV-7 DNA were detected in three and one patients, respectively. Respiratory viruses were detected in 13 of the 42 patients. Significant growth of one or more bacterial species was observed in 17 patients. No significant association was found between the presence of CMV DNA and the detection of other microorganisms. The data indicated that the presence of CMV DNA in the lower respiratory tract is a frequent finding in children with chronic or recurrent bronchopulmonary diseases. Further, prospective observational studies are needed to assess the impact of this phenomenon, if any, on the clinical course of these patients.