Analysis of a newly discovered antigen of Bacillus cereus biovar anthracis for its suitability in specific serological antibody testing.

AIMS: The aim of this work was to identify a protein which can be used for specific detection of antibodies against Bacillus cereus biovar anthracis (Bcbva), an anthrax-causing pathogen that so far has been described in African rainforest areas. METHODS AND RESULTS: Culture supernatants of Bcbva and classic Bacillus anthracis (Ba) were analysed by gel electrophoresis, and a 35-kDa protein secreted only by Bcbva and not Ba was detected. The protein was identified as pXO2-60 by mass spectrometry. Sequence analysis showed that Ba is unable to secrete this protein due to a premature stop codon in the sequence for the signal peptide. Immunization of five outbred mice with sterile bacterial culture supernatants of Bcbva revealed an immune response in ELISA against pXO2-60 (three mice positive, one borderline) and the protective antigen (PA; four mice). When supernatants of classic Ba were injected into mice or human sera from anthrax patients were analysed, only antibodies against PA were detected. CONCLUSIONS: In combination with PA, the pXO2-60 protein can be used for the detection of antibodies specific against Bcbva and discriminating from Ba. SIGNIFICANCE AND IMPACT OF THE STUDY: After further validation, serological assays based on pXO2-60 can be used to perform seroprevalence studies to determine the epidemiology of B. cereus bv anthracis in affected countries and assess its impact on the human population.

HIV-positive men who have sex with men are at high risk of development of significant liver fibrosis after an episode of acute hepatitis C.

Acute hepatitis C virus infection remains a major health concern in human immunodeficiency virus(HIV)-infected men who have sex with men (MSM). New direct-acting antiviral agent (DAA) combination therapy has not yet been approved for the treatment for acute hepatitis C virus(HCV), thereby potentially causing deferral of HCV treatment. Therefore, we aimed to study the course of liver disease after an episode of acute HCV. This study is a retrospective single-centre cohort of HIV-positive MSM with acute HCV infection. Liver fibrosis was estimated by Fibroscan® and Fibrotest® . Liver-related and non-liver-related outcomes were documented. Overall 213 episodes of acute HCV infection in 178 men were documented. Median follow-up for all included patients was 38.7 months. Spontaneous HCV clearance was found in 10.8% of patients, which was significantly associated with older age, lower HCV RNA levels, and higher ALT levels upon initial acute HCV diagnosis. Treatment with interferon-based therapy was initiated in 86.3% of cases, resulting in a sustained virological response(SVR) rate of 70.7%. After 3 years' follow-up, significant liver fibrosis of METAVIR F2 stage or higher was found in 39.4% of patients after first acute HCV diagnosis. Higher age, physician-declared alcoholism, and nonresponse to acute HCV therapy were independently associated with higher fibrosis stages. Ten patients died during the observation period (IR 1.4/100 patient-years) and four during interferon treatment. Significant liver fibrosis is a common finding in HIV-positive MSM following acute HCV infection despite high treatment uptake and cure rates, suggesting the need for close liver disease monitoring particularly if HCV treatment is deferred.

Multiple hepatitis C virus (HCV) reinfections in HIV-positive men who have sex with men: no influence of HCV genotype switch or interleukin-28B genotype on spontaneous clearance.

OBJECTIVES: The incidence of sexually transmitted hepatitis C virus (HCV) reinfection is on the rise in HIV-infected men who have sex with men (MSM). Data on natural history of acute hepatitis C and possible factors associated with spontaneous clearance are limited. The aim of this study was to analyse the outcome of HCV reinfections in HIV-positive MSM. METHODS: A retrospective analysis was carried out on patients with more than one sexually acquired HCV infection who were diagnosed at four major German HIV and hepatitis care centres. Reinfection was defined by genotype or phylogenetic clade switch, detectable HCV RNA after a sustained virological response (SVR) or after spontaneous clearance (SC). RESULTS: In total, 48 HIV-positive MSM were identified with HCV reinfection, among them 11 with a third episode and one patient with four episodes. At the first episode, 43 and five patients had an SVR and SC, respectively. The second episode was accompanied by a genotype switch in 29 patients (60%). Whereas 30 and nine patients showed an SVR and SC, respectively, eight patients developed chronic hepatitis. Neither HCV genotype switch nor interleukin-28B genotype was associated with SC. However, SC rates at the second episode were higher for patients with SC at the first episode compared with patients without SC (60 vs. 14%, respectively; P = 0.03). Two patients with SC at the first episode were reinfected with the same genotype. CONCLUSIONS: Multiple reinfections in HIV-infected MSM do occur, with or without genotype switch, and with prior SC of previous episodes. In this large case series, except for SC at the first episode, no factor was of value in clinical decision-making for early therapeutic intervention in acute HCV reinfection.

High rates of quinolone-resistant strains of Shigella sonnei in HIV-infected MSM.

PURPOSE: There is increasing evidence that shigellosis is a predominantly sexually transmitted disease among men who have sex with men (MSM) and that infection with the human immunodeficiency virus (HIV) is a risk factor for shigellosis. METHODS: Retrospective analysis of antibiotic resistance profiles of Shigella species isolated from stool specimens of patients presenting with diarrhea from January 2010 to July 2012 in three German outpatient clinics specialized in HIV care. RESULTS: Among 79 cases of Shigella sonnei, 56 occurred in HIV-infected MSM, while 23 were observed in HIV-negative MSM. High resistance rates (>90%) were found for doxycycline, tetracycline, aminoglycosides, all cephalosporins of first and second generations tested, and trimethoprim/sulfamethoxazole. In total, 54% of cases were resistant to ciprofloxacin. Compared to negative subjects, HIV-infected MSM had a significantly higher rate of quinolone resistance. For ciprofloxacin, the resistance rates were 66 versus 24%, respectively (p = 0.0016). Individual resistance patterns did not indicate that this was due to a limited outbreak. Rates of resistance to other antibiotics than quinolones showed no differences between HIV-infected and HIV-negative cases. No resistance was found for carbapenems or newer cephalosporins such as ceftriaxone. CONCLUSIONS: The high rates of S. sonnei isolates resistant to quinolones and other traditional antibiotics are of concern. Innovative prevention efforts are urgently needed. The empirical use of quinolones in HIV-infected patients presenting with S. sonnei infection is no longer recommended.

Impact of earlier HAART initiation on the immune status and clinical course of treated patients on the basis of cohort data of the German Competence Network for HIV/AIDS.

PURPOSE: Hitherto, studies on highly active antiretroviral therapy (HAART) initiation have shown partly inconsistent results. Our study investigated the clinical course and course of immune status after HAART initiation at CD4-cell-count/µl of treated patients between 250 and 349 (group 1), compared to 350-449 (group 2), on the basis of the cohort of the Competence Network for HIV/AIDS (KompNet cohort). METHODS: Patients had to be HAART-naïve. Medication had to start at the earliest in 1996, being at least triple combination therapy. The primary endpoints of death, first AIDS-defining illness and first drop of CD4-cell-count/µl below 200 were evaluated as censored event times between the initiation of HAART (t (0)) and the date of the first event/date of last observation. Probabilities of event-free intervals since t (0) were calculated by Kaplan-Meier estimation, compared by logrank tests. The results were adjusted for confounders using Cox regression. Additionally, incidences were estimated. RESULTS: A total of 822 patients met the inclusion criteria (group 1: 526, group 2: 296), covering 4,133 patient years (py) overall. In group 1, 0.64 death cases/100 py were found, with the corresponding vale being 0.17 in group 2. In group 1, 1.38 AIDS-defining events/100 py occurred, whereas it was 0.78 in group 2. In group 1, 2.64 events of first drop of CD4-cell-count/µl below 200 occurred per 100 py, compared to 0.77 in group 2. Kaplan-Meier estimations showed borderline significant differences regarding death (p = 0.063), no differences regarding first AIDS-defining illness (p = 0.148) and distinct differences regarding the first drop of CD4-cell-count/µl below 200 (p = 0.0004). CONCLUSIONS: The results gave a strong hint for a therapy initiation at higher CD4-cell-count/µl regarding the outcome of death in treated patients. A distinct benefit was shown regarding the first decline of CD4-cell-count/µl below 200.

The Patient Cohort of the German Competence Network for HIV/AIDS (KompNet): a profile.

OBJECTIVE: In this paper, we describe the main objectives, the study design and the onset of the patient cohort of the German Competence Network for HIV/AIDS (KompNet) (www.kompetenznetz-hiv.de). Furthermore, we depict sociodemographic and clinical baseline characteristics and an estimation of the coverage and representativity as to the composition of persons living with HIV/AIDS (PLWHA) in Germany. METHODS: The KompNet cohort is an open, retrospective and prospective, multicenter, disease-specific and nationwide cohort study that started gathering data in June 2004. Semi-annually, follow up visits of the patients are documented, covering clinical and sociodemographic data. At enrolment and three years afterwards, an EDTA-sample is taken; a serum-sample is taken at every follow up visit. RESULTS: As of 14.9.2008, a total of 15,541 patients were enrolled by 44 documenting sites. In September 2007, the cohort size was reduced to 10 outpatient clinics and fifteen private practitioners, covering a total of 9,410 patients. The documentation of these patients comprises 24,117 years of follow up-time since enrolment (mean: 2.6 years), 62,862 person years inclusive data documented retrospectively on course of HIV-infection and combined antiretroviral therapy (cART, mean: 6.7 years). 1,008 patients (10.7%) were lost to follow up and 175 (1.9%) died since enrolment. 84.9% of patients were men. Main risks of transmission were sex between men (MSM: 62.9%), heterosexual contacts (18.4%), intravenous drug use (IVDU: 7.0%) and origin from a high prevalence country (HPL: 5.2%). Mean age was 45 years. CONCLUSION: The KompNet cohort covers about a quarter of all patients being under treatment in Germany. The composition of the cohort represents well the most important risks of transmission in Germany. The cohort contains a high proportion of patients being older than 49 years (28.1%). On basis of its comprehensive database and its biomaterials banks, the KompNet cohort serves as an important instrument to monitor and analyse the effects of combined antiretroviral therapy (cART) in Germany, interdigidating basis, clinical and psychosocial research in view to translational research.

Treatment during primary HIV infection does not lower viral set point but improves CD4 lymphocytes in an observational cohort.

OBJECTIVE: To investigate if early treatment of primary HIV-1 infection (PHI) reduces viral set point and/or increases CD4 lymphocytes. METHODS: Analysis of two prospective multi-centre PHI cohorts. HIV-1 RNA and CD4 lymphocytes in patients with transient treatment were compared to those in untreated patients. Time to CD4 lymphocyte decrease below 350/ microl after treatment stop or seroconversion was calculated using Kaplan-Meier and Cox-PH-regression analyses. RESULTS: 156 cases of PHI were included, of which 100 had received transient HAART (median treatment time 9.5 months) and 56 remained untreated. Median viral load (563000 cop/ml vs 240000 cop/ml; p<0.001) and median CD4 lymphocyte (449/ microl vs. 613/ microl; p<0.01) differed significantly between treated and untreated patients. Median viral load was 38056 copies/ml in treated patients (12 months after treatment stop) and 52880 copies/ml in untreated patients (12 months after seroconversion; ns). Median CD4 lymphocyte change was +60/ microl vs. -86/ microl (p = 0.01). Median time until CD4 lymphocytes decreased to <350/ microl (including all patients with CD4 lymphocytes <500/ microl during seroconversion) was 20.7 months in treated patients after treatment stop and 8.3 months in untreated patents after seroconversion (p<0.01). Cox-PH analyses adjusting for baseline VL, CD4 lymphocytes, stage of early infection and symptoms confirmed these differences. CONCLUSIONS: Treatment during PHI did not lower viral set point. However, patients treated during seroconversion had an increase in CD4 lymphocytes, whereas untreated patients experienced a decrease in CD4 lymphocytes. Time until reaching CD4 lymphocytes <350/ microl was significantly shorter in untreated than in treated patients including patients with CD4 lymphocytes <500/ microl during seroconversion.

[Investigation of a family cluster of influenza A/H1N1 infections in Germany, 2009]. / Untersuchungen zu einem familiären Cluster von Infektionen durch Influenza A/H1N1 in Deutschland, 2009.

INTRODUCTION: On May 3, 2009, a first case of influenza A/H1N1 infection occurred in the federal state of Saxony-Anhalt, Germany. In order to stop the possible spread of the virus and to study the epidemiological and clinical characteristics of the infection, an investigation was launched by the local health authorities and the RKI. METHODS: Standardised questionnaires were used to assess demographic and clinical data. Specimens were collected from case patients and close contacts and were analysed for influenza A/H1N1 using real-time PCR. RESULTS: The index patient showed fever and coughing 3.5 days after returning from a holiday in Mexico. The local health authorities were informed on May 3, and measures were rapidly implemented. These measures included a trace-back of possible contact persons, isolation of the case and close contacts, prophylactic treatment with Oseltamivir. Virological investigations showed that the case shedded viral genome up until the last day of antiviral therapy. Viral genome was also detected in the spouse and the son of the patient. Both showed no symptoms under a prophylactic treatment with antiviral medication. No viral genome was detected in three other family members, and in six other contact persons outside of the family. DISCUSSION: The spread of the virus was contained due to the fast response of the local health authorities. Two secondary cases occurred in the family. These cases remained asymptomatic, possibly due to antiviral prophylaxis. Epidemiological and virological results suggest that the influenza A/H1N1 virus has a longer incubation period and that viral shedding may probably be prolonged when compared with seasonal influenza.

N-terminal pro-B-type natriuretic peptide (NT-proBNP) in HIV-1 infected individuals on HAART.

BACKGROUND: Studies suggest that highly active anti-retroviral therapy (HAART) prolongs life in HIV infected individuals and that HIV infected individuals increasingly suffer from cardiovascular complications. NT-proBNP has been shown to represent an indicator of cardiac function. METHODS: 495 HIV infected individuals under HAART and 1980 blood donors (BD) were tested for N-terminal pro-B-type natriuretic peptide (NT-proBNP). NT-proBNP was performed by an automated electrochemiluminescence immunoassay (ECLIA) method. RESULTS: HIV infected individuals had significantly higher NT-proBNP levels than age matched blood donors (18-29 y: median: 33 pg/ml HIV vs. 5 pg/ml BD; p = 0.0247; 30-39 y: median: 25 pg/ml HIV vs. 5 pg/ml BD; p = 0.0351; 40-49 y: median: 35.5 pg/ml HIV vs. 5 pg/ml BD; p < 0.0001; 50-59 y: median: 42 pg/ml HIV vs. 36 pg/ml BD; p = 0.3665; 60-69 y: median: 82.5 pg/ml HIV vs. 46 pg/ml BD; p = 0.0055) the effect was consistently found in all age and both gender groups. HIV infected individuals differed from the blood donor control group with respect to cardiovascular risk factors (hypertension, cardiovascular (CV) medication, diabetes mellitus, smoking status). In HIV infected individuals NT-proBNP levels did not correlate to cardiovascular risk factors including GFR except for C-reactive protein (CRP) levels using multivariate analysis. There was also no evidence for cardiotoxic effects due to HAART or specific antiretroviral drugs. High NT-proBNP levels were found in Hepatitis C virus (HCV) infected individuals who had received alpha-interferon therapy. CONCLUSIONS: HIV infected individuals had higher NT-proBNP levels than age matched blood donors possibly as a result of a higher prevalence of general cardiovascular risk factors and HIV associated risk factors, the finding is consistent with an increased incidence of cardiovascular events described in HIV infected individuals. Further studies on the relationship to cardiovascular outcome are warranted.

Impact of transmission of drug-resistant HIV on the course of infection and the treatment success. Data from the German HIV-1 Seroconverter Study.

BACKGROUND: Data on the clinical course of infection in patients with transmitted drug-resistant HIV before and after initiation of treatment are scarce. PATIENTS AND METHODS: Genotypic resistance was analysed in 504 therapy-naïve individuals with a known date of infection. Resistance was predicted using the Stanford algorithm. Clinical parameters for 80 individuals with transmitted drug-resistant HIV and for 424 patients with susceptible virus were analysed. RESULTS: In 16% of the individuals transmitted drug-resistant HIV was found. Detection of drug-resistant HIV was more likely in individuals with acute primary HIV infection [odds ratio (OR)=1.529; 95% confidence interval (95% CI) 1.001; 2.236]. At the time of infection patients with an acute infection with resistant HIV had lower viral loads. CD4 cell counts tended to be higher and the CD4 cell loss more pronounced in the group with resistant HIV. Suppression of the viral load below the detection limit was achieved in 64% of the group with resistant HIV and in 85% of the group with susceptible HIV 6 months after initiation of therapy (P=0.199). The majority of the group with resistant HIV (74%) received at least one compromised drug. CONCLUSION: First-line treatment including drugs with predicted resistance can impair virological success in some patients. Factors influencing the decision to include compromised drugs need to be investigated.