Walter Hampl

Active Cytomegalovirus Infection in Patients with Septic Shock

Cytomegalovirus reactivation occurred in one third of patients and was associated with prolonged ventilation and stay in an intensive care unit.

Thrombocytopenia and Acute Renal Failure in Puumala Hantavirus Infections

Low platelet counts are a novel predictive marker suitable for risk-adapted patient management.

Cellular Immunity and Active Human Cytomegalovirus Infection in Patients with Septic Shock

BACKGROUND Human cytomegalovirus (CMV) is an important opportunistic pathogen after transplantations. In the present study, monitoring of CMV in patients with septic shock was used to discover whether T helper cell type 1 (Th1) cell and natural killer (NK) cell functions interact with CMV reactivation in patients not undergoing immunosuppressive therapy. METHODS Thirty-eight patients with septic shock were monitored, and the 23 CMV-seropositive patients were included in this prospective study. RESULTS Seven patients (30.4%) developed an active CMV infection despite the detection of CMV-reactive Th1 cells. After active CMV infection, the frequency of CMV-reactive Th1 cells increased from a median of 0.52% to 5.04% (P=.009). Active CMV infections were terminated without antiviral therapy within 2 weeks. In parallel, the frequency of staphylococcal enterotoxin B (SEB; superantigen)-reactive Th1 cells increased from a median of 1.11% to 8.48% (P=.027). In patients without active CMV infection, the frequency of CMV-reactive (median, 0.39%) and SEB-reactive (median, 1.11%) Th1 cells did not increase. Cytotoxic NK cell activity was persistently suppressed despite the presence of CD56(+)CD16(+) NK cells. Moreover, interleukin-2 application in vitro did not restore NK cell activity. CONCLUSIONS A proinflammatory immune response may contribute to CMV reactivation in patients with septic shock. Adaptive T cell immunity, more likely than NK cell immunity, may contribute to termination of active CMV infection without antiviral therapy in these patients.

Phosphorylation of aciclovir, ganciclovir, penciclovir and S2242 by the cytomegalovirus UL97 protein : a quantitative analysis using recombinant vaccinia viruses

We used recombinant vaccinia viruses (rVV) containing the UL97 open reading frame (ORF) of the human cytomegalovirus (HCMV) to investigate the UL97-dependent phosphorylation of different nucleoside analogs. The rVV T1 expressed the wild-type UL97 protein whereas rVV A5 contained a 12 bp deletion in the UL97 which had been known to be responsible for resistance of HCMV to ganciclovir (GCV). The rVV T1opal was generated which contained a stop codon at position 1089 of the UL97 ORF and which expressed a truncated UL97 protein. We quantitatively analyzed the capability of these rVVs to phosphorylate GCV, penciclovir (PCV), aciclovir (ACV) and 2-amino-7-[(1,3-dihydroxy-2-propoxy)methyl] purine (S2242) as well as the natural nucleosides deoxycytidine and deoxythymidine. Moreover, we compared their phosphorylating capability with that of herpes simplex virus type 1 strains. In thymidine kinase (TK)-deficient 143B cells infected with rVV T1, the three compounds GCV, ACV and PCV were phosphorylated with different efficiency whereas in cells infected with the rVV A5 a markedly reduced but not completely abolished phosphorylation of these compounds was observed. In rVV T1opal-infected cells no specific phosphorylation of the compounds was detectable at all. Neither S2242 nor the natural substrates of TKs were phosphorylated by any of the vaccinia recombinants. The rVVs proved to be a suitable tool for analysis of UL97-dependent phosphorylation of nucleoside analogs and also allowed to quantitatively study the influence of UL97 mutations on drug phosphorylation.

High Variability between Results of Different In-House Tests for Cytomegalovirus (CMV) Monitoring and a Standardized Quantitative Plasma CMV PCR Assay

ABSTRACT A total of 2,718 blood samples were analyzed in five virological laboratories for the presence of cytomegalovirus (CMV) by in-house tests and one standardized plasma PCR assay. Results from in-house tests showed remarkable variability. Detection of CMV pp65 antigen or DNA from cells was more sensitive than that by plasma CMV PCR assay.

Reactivated fulminant hepatitis B virus replication after bone marrow transplantation: clinical course and possible treatment with ganciclovir

A female chronic hepatitis B virus carrier (HBV-DNA negative) suffered from simultaneous hepatitis B virus and cytomegalovirus reactivation after in vivo T cell depletion preceding transplantation of an in vitro T cell depleted marrow graft for treatment of acute leukaemia. Interstitial pneumonia developing after bone marrow transplantation was successfully treated with ganciclovir (day 13 until day 46). The initially unnoticed extensive hepatitis B virus replication finally led to clinical hepatitis (day 85) and liver failure (day 96). Liver transplantation was performed, but the patient died from septicaemia. Retrospective analysis of hepatitis B virus DNA revealed that the HBV replication started immediately after T cell depletion and was completely suppressed during ganciclovir administration. Screening for HBV-DNA seems to be mandatory in comparable cases, and antiviral chemotherapy should be seriously considered.

Post-Pandemic Seroprevalence of Pandemic Influenza A (H1N1) 2009 Infection (Swine Flu) among Children <18 Years in Germany

Background We determined antibodies to the pandemic influenza A (H1N1) 2009 virus in children to assess: the incidence of (H1N1) 2009 infections in the 2009/2010 season in Germany, the proportion of subclinical infections and to compare titers in vaccinated and infected children. Methodology/Principal Findings Eight pediatric hospitals distributed over Germany prospectively provided sera from in- or outpatients aged 1 to 17 years from April 1st to July 31st 2010. Vaccination history, recall of infections and sociodemographic factors were ascertained. Antibody titers were measured with a sensitive and specific in-house hemagglutination inhibition test (HIT) and compared to age-matched sera collected during 6 months before the onset of the pandemic in Germany. We analyzed 1420 post-pandemic and 300 pre-pandemic sera. Among unvaccinated children aged 1–4 and 5–17 years the prevalence of HI titers (≥1∶10) was 27.1% (95% CI: 23.5–31.3) and 53.5% (95% CI: 50.9–56.2) compared to 1.7% and 5.5%, respectively, for pre-pandemic sera, accounting for a serologically determined incidence of influenza A (H1N1) 2009 during the season 2009/2010 of 25,4% (95% CI : 19.3–30.5) in children aged 1–4 years and 48.0% (95% CI: 42.6–52.0) in 5–17 year old children. Of children with HI titers ≥1∶10, 25.5% (95% CI: 22.5–28.8) reported no history of any infectious disease since June 2009. Among vaccinated children, 92% (95%-CI: 87.0–96.6) of the 5–17 year old but only 47.8% (95%-CI: 33.5–66.5) of the 1–4 year old children exhibited HI titers against influenza A virus (H1N1) 2009. Conclusion Serologically determined incidence of influenza A (H1N1) 2009 infections in children indicates high infection rates with older children (5–17 years) infected twice as often as younger children. In about a quarter of the children with HI titers after the season 2009/2010 subclinical infections must be assumed. Low HI titers in young children after vaccination with the AS03B-adjuvanted split virion vaccine need further scrutiny.

Post-Pandemic Seroprevalence of Pandemic Influenza A (H1N1) 2009 Infection (Swine Flu) among Children

Background We determined antibodies to the pandemic influenza A (H1N1) 2009 virus in children to assess: the incidence of (H1N1) 2009 infections in the 2009/2010 season in Germany, the proportion of subclinical infections and to compare titers in vaccinated and infected children. Methodology/Principal Findings Eight pediatric hospitals distributed over Germany prospectively provided sera from in- or outpatients aged 1 to 17 years from April 1st to July 31st 2010. Vaccination history, recall of infections and sociodemographic factors were ascertained. Antibody titers were measured with a sensitive and specific in-house hemagglutination inhibition test (HIT) and compared to age-matched sera collected during 6 months before the onset of the pandemic in Germany. We analyzed 1420 post-pandemic and 300 pre-pandemic sera. Among unvaccinated children aged 1–4 and 5–17 years the prevalence of HI titers (≥1∶10) was 27.1% (95% CI: 23.5–31.3) and 53.5% (95% CI: 50.9–56.2) compared to 1.7% and 5.5%, respectively, for pre-pandemic sera, accounting for a serologically determined incidence of influenza A (H1N1) 2009 during the season 2009/2010 of 25,4% (95% CI : 19.3–30.5) in children aged 1–4 years and 48.0% (95% CI: 42.6–52.0) in 5–17 year old children. Of children with HI titers ≥1∶10, 25.5% (95% CI: 22.5–28.8) reported no history of any infectious disease since June 2009. Among vaccinated children, 92% (95%-CI: 87.0–96.6) of the 5–17 year old but only 47.8% (95%-CI: 33.5–66.5) of the 1–4 year old children exhibited HI titers against influenza A virus (H1N1) 2009. Conclusion Serologically determined incidence of influenza A (H1N1) 2009 infections in children indicates high infection rates with older children (5–17 years) infected twice as often as younger children. In about a quarter of the children with HI titers after the season 2009/2010 subclinical infections must be assumed. Low HI titers in young children after vaccination with the AS03B-adjuvanted split virion vaccine need further scrutiny.

CMV monitoring using blood cells and plasma: a comparison of apples with oranges?

Quantitative cytomegalovirus (CMV) monitoring is still far from being standardized between transplant centers. In the present study, we compared assays for quantitative CMV monitoring using blood cells and plasma. Four hundred and thirty-five consecutive samples from 29 patients with active CMV infection after allogeneic T-cell-depleted hemopoietic stem cell transplantation were tested in parallel using pp65 antigenemia and quantitative CMV polymerase chain reaction (PCR) in blood cells and plasma (COBAS AMPLICOR CMV MONITOR). Although only 142 (53.1%) of 253 positive samples were concordantly identified by all three assays, the number of positive samples detected by each assay was not different and the quantitative values were correlated, provided that nucleic acid (NA) in plasma was isolated by COBAS AmpliPrep and not by the manual protocol. Six (18%) of 34 episodes with active CMV infection were not detected using CMV PCR in plasma; whereas in times of white blood cell aplasia or blast crisis of leukemia, samples with active CMV infection in plasma could not be detected using blood cells. We conclude that CMV monitoring in whole blood could be favorable compared with assays using plasma or blood cells alone. Automated NA isolation could become an attractive tool for a more sensitive and better standardized molecular diagnostics.

Viral pathogens and epidemiology, detection, therapy and resistance

Worldwide community-acquired pneumonia (CAP) is one of the most frequent infectious diseases and a leading cause of death. Several studies have shown that a pathogen could be identified only in 50 to 60% of all patients, although in children < 6 month infectious agents can be detected in about 90%. Viral infections are most frequent in children < 2 years (80%), whereas bacterial infections increase with age. RSV, influenzaviruses, rhinoviruses, parainfluenzaviruses and adenoviruses are the most common viruses associated with CAP in children. Among adenoviruses a predominance of adenovirus 7 has been reported in several countries with emergence of highly pathogenic variants with significant lethality in young children. Many childhood respiratory infections are caused by more than one pathogen and up to 30% mixed viral / bacterial infections can be observed. CAP in immunocompetent adults is rare, whereas persons with underlaying diseases have an increased incidence of CAP. In the elderly, RSV, influenzaviruses, parainfluenzaviruses and less frequent adenoviruses are predominant viruses causing pneumonia. Less frequently associated with CAP are the newly discovered human metapneumovirus and the coronaviruses NL63 and HKU1. Hantaviruses, involved in the hantavirus pulmonary syndrome, belong to the emerging pathogens to date in North, Middle and South America. For optimum diagnosis the whole spectrum of potential respiratory viral agents should be included and multiple diagnostic techniques have to be used. In view of the high relevance of influenzavirus for CAP influenza vaccination is highly advisable for prevention of CAP, especially in high-risk groups.