Soluble urokinase plasminogen activator receptor (suPAR) is a novel, independent predictive marker of myocardial infarction in HIV-1-infected patients: a nested case-control study.

OBJECTIVES: Patients infected with HIV are at increased risk of myocardial infarction (MI). Increased plasma levels of the inflammatory biomarker soluble urokinase plasminogen activator receptor (suPAR) have been associated with increased risk of cardiovascular diseases (CVD), including MI in the general population. We tested suPAR as a predictive biomarker of MI in HIV-1-infected individuals. METHODS: suPAR levels were investigated in a nested case-control study of 55 HIV-1-infected cases with verified first-time MI and 182 HIV-1-infected controls with no known CVD. Controls were matched for age, gender, duration of antiretroviral therapy (ART), smoking and no known CVD. suPAR was measured in the four plasma samples available for each patient at different time-points; 1, Before initiation of ART; 2, 3 months after initiation of ART; 3, 1 year before the case's MI; and 4, The last sample available before the case's MI. RESULTS: In unadjusted conditional regression analysis, higher levels of suPAR were associated with a significant increase in risk of MI at all time-points. Patients in the third and fourth suPAR quartiles had a three- to 10-fold higher risk of MI compared to patients in the lowest suPAR quartile at all time-points. suPAR remained a strong significant predictor of MI, when adjusting for HIV-1 RNA, total cholesterol, triglycerides and high-density lipoprotein. CONCLUSION: Elevated suPAR levels were associated with increased risk of MI in HIV-infected patients, suggesting that suPAR could be a useful biomarker for prediction of first-time MI in this patient group, even years before the event.

Utilization of psychotropic drugs prescribed to persons with and without HIV infection: a Danish nationwide population-based cohort study.

OBJECTIVES: The objective was to estimate the utilization of psychotropic drugs in HIV-infected individuals compared with that in the background population. METHODS: Using data obtained from the Danish HIV Cohort Study and the Danish National Prescription Registry, we analysed aggregated data on redeemed prescription of psychotropic drugs during 1995-2009. We primarily focused our analyses on HIV-infected individuals with no history of injecting drug use (IDU) or hepatitis C virus (HCV) infection. Drug utilization was expressed as defined daily doses per 1000 person-days (DDD/1000PD). The utilization rate ratio (URR) was calculated as utilization in the HIV-infected cohort compared with that in the comparison cohort. We estimated longitudinal trends in utilization and potential associations with HIV and exposure to highly active antiretroviral therapy (HAART), especially efavirenz. RESULTS: During 1995-2009, 54.5% of the HIV-infected cohort (3615 non-IDU/non-HCV-infected HIV-infected individuals) and 29.2% of the comparison cohort (32 535 individuals) had at least one prescription of a psychotropic drug. HIV infection was associated with a URR of 1.13 for antipsychotics, 1.76 for anxiolytics, 4.42 for hypnotics and sedatives, and 2.28 for antidepressants. Antidepressants were confined primarily to men who have sex with men (MSM). Older age, more recent calendar time, and increased time after HIV diagnosis were associated with increased drug utilization. However, no association with exposure to HAART or efavirenz was found. CONCLUSIONS: HIV-infected individuals had a higher utilization of psychotropic drugs than the background population, which was not confined to individuals with a history of IDU or HCV infection. This emphasizes the need to focus on diagnosis of, and appropriate psychopharmacological interventions for, mental disorders in this population.

No change in viral set point or CD4 cell decline among antiretroviral treatment-naïve, HIV-1-infected individuals enrolled in the Danish HIV Cohort Study in 1995-2010.

OBJECTIVES: Recent studies have reported faster progression of HIV infection than anticipated based on results from earlier studies. The aim of the present study was to examine if the virulence of HIV-1 infection changed in the period 1995-2010 among chronically HIV-infected individuals in Denmark. METHODS: We included all patients registered in the Danish HIV Cohort Study, who were diagnosed in 1995-2009, had a CD4 count > 100 cells/µL at diagnosis and had at least two CD4 measurements prior to initiation of antiretroviral therapy (ART). Changes in viral set point and rate of CD4 cell decline from enrolment until the initiation of ART by calendar year of HIV diagnosis were analysed. Time to first CD4 count < 350 cells/µL was compared among patients diagnosed in 1995-2000, 2001-2005 and 2006-2010. RESULTS: We followed 1469 HIV-infected patients for a total of 5783 person-years. The median viral set point was 4.27 log10 HIV-1 RNA copies/mL [interquartile range (IQR) 3.58-4.73 log10 copies/mL]. The median CD4 cell decline per year was 57 cells/µL (IQR 10-139 cells/µL). In analyses adjusted for age, gender, origin, route of transmission and CD4 count at diagnosis, there were no associations between year of diagnosis and viral set point or CD4 cell decline. Time to first CD4 count < 350 cells/µL did not change in the study period [incidence rate ratio (IRR) 0.90 (95% confidence interval (CI) 0.76-1.06) for 2001-2005 and 1.09 (95% CI 0.79-1.34) for 2006-2010 compared with 1995-2000]. CONCLUSIONS: We found no evidence of changing trends in viral set point, CD4 cell decline or time to CD4 count < 350 cells/µL during the period 1995-2010 in a cohort of chronically HIV-infected individuals.

The rate of accumulation of nonnucleoside reverse transcriptase inhibitor (NNRTI) resistance in patients kept on a virologically failing regimen containing an NNRTI*.

BACKGROUND: Virological failure of first-generation nonnucleoside reverse transcriptase inhibitors (NNRTIs) can compromise the efficacy of etravirine as a result of the accumulation of NNRTI resistance mutations. How quickly NNRTI resistance accumulates in patients with a delayed switch from nevirapine or efavirenz despite virological failure, when these drugs are used as a component of combination antiretroviral therapy (cART), remains unclear. METHODS: The rate of NNRTI resistance accumulation was estimated in patients in EuroSIDA with at least two available genotypic resistance tests (GRTs), provided that (1) the date of the first GRT (t0) was after the date of the first virological failure (VF) of an NNRTI, and (2) patients were receiving an NNRTI and HIV RNA was >500 HIV-1 RNA copies/mL in all measurements between GRTs. RESULTS: A total of 227 patients were included in the study, contributing 467 GRT pairs. At baseline-t0, a median of 3 months after VF, 66% of patients had at least one NNRTI mutation: 103N (34%), 181C (22%) and 190A (20%) were the most common mutations. Overall, 180 additional NNRTI mutations were found to have accumulated over 295 years [1 new/1.6 years; 95% confidence interval (CI) 1.5-1.8]. The rate of accumulation was faster in the first 6 months from VF (1 new/1.1 years), and slower in patients exposed to nevirapine vs. those receiving efavirenz [relative risk (RR) 0.66; 95% CI 0.46-0.95; P=0.03]. CONCLUSIONS: There is an initial phase of rapid accumulation of NNRTI mutations close to the time of VF followed by a phase of slower accumulation. We predict that it should take approximately one year of exposure to a virologically failing first-generation NNRTI-based cART regimen to reduce etravirine activity from fully susceptible to intermediate resistant, and possibly longer in patients kept on a failing nevirapine-containing regimen.

Major but differential decline in the incidence of Staphylococcus aureus bacteraemia in HIV-infected individuals from 1995 to 2007: a nationwide cohort study*.

OBJECTIVES: Incidence rates (IRs) of Staphylococcus aureus bacteraemia (SAB) are known to be higher in HIV-infected individuals than in the general population, but have not been assessed in the era of highly active antiretroviral therapy. METHODS: From 1 January 1995 to 31 December 2007, all Danish HIV-infected individuals (n=4871) and population controls (n=92 116) matched on age and sex were enrolled in a cohort and all cases of SAB were registered. IRs and risk factors were estimated using time-updated Poisson regression analysis. RESULTS: We identified 329 cases of SAB in 284 individuals, of whom 132 individuals were infected with HIV and 152 were not [crude IR ratio (IRR) 24.2; 95% confidence interval (CI) 19.5-30.0, for HIV-infected vs. non-HIV-infected individuals]. Over time, IR declined for HIV-infected individuals (IRR 0.40). Injecting drug users (IDUs) had the highest incidence and the smallest decline in IR, while men who have sex with men (MSM) had the largest decline over time. Among HIV-infected individuals, a latest CD4 count <100 cells/µL was the strongest independent predictor of SAB (IRR 10.2). Additionally, HIV transmission group was associated with risk of SAB. MSM were more likely to have hospital-acquired SAB, a low CD4 cell count and AIDS at the time of HIV acquisition compared with IDUs. CONCLUSIONS: We found that the incidence of SAB among HIV-infected individuals declined during the study period, but remained higher than that among HIV-uninfected individuals. There was an unevenly distributed burden of SAB among HIV transmission groups (IDU>MSM). Low CD4 cell count and IDU were strong predictors of SAB among HIV-infected individuals.

Causes of death among Danish HIV patients compared with population controls in the period 1995-2008.

PURPOSE: To compare the mortality and causes of death in human immunodeficiency syndrome (HIV) patients with the background population. METHODS: All adult HIV patients treated in Danish HIV centers from 1995 to 2008 and 14 controls for each HIV patient were included. Age-adjusted mortality rates (MR) and mortality rate ratios (MRR) were estimated using direct standardization and Poisson regression analyses. Up to four contributory causes of death for each person were included in analyses of cause-specific MR. RESULTS: A total of 5,137 HIV patients and 71,918 controls were followed for 37,838 and 671,339 person-years (PY), respectively. Among non-injection drug use (IDU) HIV patients, the acquired immune deficiency syndrome (AIDS)-related MR/1,000 PY declined dramatically from 122.9 [95 % confidence interval (CI) 106.8-141.4] in 1995 to 5.0 (95 % CI 3.1-8.1) in 2008. The non-AIDS-related MR did not change substantially from 6.9 (95 % CI 3.8-12.5) to 5.6 (95 % CI 3.6-8.8). The MR of unnatural causes declined from 6.9 (95 % CI 3.8-12.5) to 2.7 (95 % CI 1.4-5.1). The MRR of infections declined from 46.6 (95 % CI 19.6-110.9) to 3.3 (95 % CI 1.6-6.6). The MRR of other natural causes of death remained constant. CONCLUSIONS: After the introduction of highly active antiretroviral therapy (HAART), the AIDS-related mortality has decreased substantially, but the long-term exposure to HIV and HAART has not translated into increasing mortality from malignancy, cardiovascular, and hepatic diseases.

HIV and risk of venous thromboembolism: a Danish nationwide population-based cohort study.

OBJECTIVE: The association between HIV infection and the risk of venous thromboembolism (VTE) is controversial. We examined the risk of VTE in HIV-infected individuals compared with the general population and estimated the impact of low CD4 cell count, highly active antiretroviral therapy (HAART) and injecting drug use (IDU). METHODS: We identified 4333 Danish HIV-infected patients from the Danish HIV Cohort Study and a population-based age- and gender-matched comparison cohort of 43,330 individuals. VTE diagnoses were extracted from the Danish National Hospital Registry. Cumulative incidence curves were constructed for time to first VTE. Incidence rate ratios (IRRs) and impact of low CD4 cell count and HAART were estimated by Cox regression analyses. Analyses were stratified by IDU, adjusted for comorbidity and disaggregated by overall, provoked and unprovoked VTE. RESULTS: The 5-year risk of VTE was 8.0% [95% confidence interval (CI) 5.78-10.74%] in IDU HIV-infected patients, 1.5% (95% CI 1.14-1.95%) in non-IDU HIV-infected patients and 0.3% (95% CI 0.29-0.41%) in the population comparison cohort. In non-IDU HIV-infected patients, adjusted IRRs for unprovoked and provoked VTE were 3.42 (95% CI 2.58-4.54) and 5.51 (95% CI 3.29-9.23), respectively, compared with the population comparison cohort. In IDU HIV-infected patients, the adjusted IRRs were 12.66 (95% CI 6.03-26.59) for unprovoked VTE and 9.38 (95% CI 1.61-54.50) for provoked VTE. Low CD4 cell count had a minor impact on these risk estimates, while HAART increased the overall risk (IRR 1.93; 95% CI 1.00-3.72). CONCLUSION: HIV-infected patients are at increased risk of VTE, especially in the IDU population. HAART and possibly low CD4 cell count further increase the risk.

Abacavir and risk of myocardial infarction in HIV-infected patients on highly active antiretroviral therapy: a population-based nationwide cohort study.

OBJECTIVE: The aim of the study was to examine whether exposure to abacavir increases the risk for myocardial infarction (MI). DESIGN, SETTING AND SUBJECTS: This was a prospective nationwide cohort study which included all Danish HIV-infected patients on highly active antiretroviral therapy (HAART) from 1995 to 2005 (N = 2952). Data on hospitalization for MI and comorbidity were obtained from Danish medical databases. Hospitalization rates for MI after HAART initiation were calculated for patients who used abacavir and those who did not. We used Cox's regression to compute incidence rate ratios (IRR) as a measure of relative risk for MI, while controlling for potential confounders (as separate variables and via propensity score) including comorbidity. MAIN OUTCOME: Relative risk of hospitalization with MI in abacavir users compared with abacavir nonusers. RESULTS: Hospitalization rates for MI were 2.4/1000 person-years (PYR) [95% confidence interval (CI) 1.7-3.4] for abacavir nonusers and 5.7/1000 PYR (95% CI 4.1-7.9) for abacavir users. The risk of MI increased after initiation of abacavir [unadjusted IRR = 2.22 (95% CI 1.31-3.76); IRR adjusted for confounders = 2.00 (95% CI 1.10-3.64); IRR adjusted for propensity score = 2.00 (95% CI 1.07-3.76)]. This effect was also observed among patients initiating abacavir within 2 years after the start of HAART and among patients who started abacavir as part of a triple nucleoside reverse transcriptase inhibitor (NRTI) regimen. CONCLUSIONS: We confirmed the association between abacavir use and increased risk of MI. Further studies are needed to control for potential confounding not measured in research to date.

Changes in biomarkers of cardiovascular risk after a switch to abacavir in HIV-1-infected individuals receiving combination antiretroviral therapy.

OBJECTIVES: To investigate, using a longitudinal design, whether biomarkers of cardiovascular risk change after a switch to an abacavir (ABC)-containing regimen in HIV-1-infected individuals already receiving combination antiretroviral therapy (ART). METHODS: Thirty-five HIV-1-infected individuals who switched ART to an ABC-containing regimen were identified. Twenty-two HIV-1-infected individuals who switched ART from and to a non-ABC-containing regimen served as controls. Plasma concentrations of soluble vascular cell adhesion molecule 1 (sVCAM-1), soluble intercellular adhesion molecule 1 (sICAM-1), matrix metallopeptidase 9 (MMP9), myeloperoxidase (MPO) and high sensitivity C-reactive protein (hs-CRP) were measured in blood samples before the switch in ART, and 3 months and 12 months afterwards. Log10-transformed data were compared with paired t-tests. RESULTS: Median MMP9 increased from 45.5 to 64.4 microg/mL after 3 months of ABC exposure (P = 0.011) and remained increased after 12 months (64.2 microg/mL; P = 0.013). MPO increased from median 8.8 to 10.4 microg/mL (P = 0.036) after 3 months of ABC exposure but was not increased after 12 months of exposure (9.1 microg/mL). hs-CRP increased from 3.3 to 4.2 microg/mL after 3 months (P = 0.031) but was not increased after 12 months of exposure (2.8 microg/mL). Neither sVCAM-1 nor sICAM-1 changed after the initiation of ABC. No changes were observed in the control group. CONCLUSIONS: MMP9, MPO and hs-CRP all increased after a switch in ART to an ABC-containing regimen. This indicates increased cardiovascular risk in viral load-suppressed HIV-1-infected individuals switching to ABC and proposes a proinflammatory potential as the underlying pathogenetic mechanism.

Reduction in circulating markers of endothelial dysfunction in HIV-infected patients during antiretroviral therapy.

OBJECTIVES: Antiretroviral therapy (ART) in HIV-infected patients is associated with increased cardiovascular risk. Circulating markers of endothelial dysfunction may be used to study early atherogenesis. The aim of our study was to investigate changes in such markers during initiation of ART. METHODS: In 115 HIV-positive treatment-naïve patients, plasma lipids, E-selectin, soluble intercellular adhesion molecule 1 (sICAM-1), soluble vascular cell adhesion molecule 1 (sVCAM-1), tissue-type plasminogen activator inhibitor 1 (tPAI-1) and high-sensitivity C-reactive protein (hsCRP) were measured before and after 2 and 14 months of ART. A control group of 30 healthy subjects was included. Values are mean+/-standard error of the mean. RESULTS: Prior to treatment, HIV-infected patients had elevated levels of sICAM-1 (296+/-24 vs. 144+/-12 ng/mL), tPAI-1 (18 473+/-1399 vs. 5490+/-576 pg/mL) and hsCRP (28 060+/-5530 vs. 6665+/-2063 ng/mL) compared with controls (P<0.001). In contrast, sVCAM-1 and E-selectin did not differ between the groups. Initiation of ART resulted in significantly lower levels of E-selectin (15.1+/-0.8; P<0.01), sICAM-1 (248+/-12 ng/mL; P<0.05), sVCAM-1 (766+/-33 ng/mL; P<0.001) and hsCRP (14 708+/-2358 ng/mL; P<0.001) after 2 months, which remained reduced at 14 months. tPAI-1 was not influenced by initiation of ART. CONCLUSIONS: Markers of endothelial dysfunction were elevated in treatment-naïve HIV-infected patients and were related to HIV RNA viral load. Initiation of ART reduced the levels of the majority of these markers. The positive effect of ART initiation was dependent on the duration of HIV infection prior to treatment.

Predictive value of soluble haemoglobin scavenger receptor CD163 serum levels for survival in verified tuberculosis patients.

Pre-treatment serum levels of sCD163 were measured in a cohort of 236 suspected tuberculosis (TB) cases from Guinea-Bissau, with a median follow-up period of 3.3 years (range 0-6.4 years). In 113 cases, the diagnosis of TB was verified by positive sputum microscopy and/or culture. Among the verified TB cases, a decreased survival rate was found in 27 patients with sCD163 levels above the upper reference limit (3.95 microg/mL). The difference in survival was significant during TB treatment (log rank, p<0.02) and after long-term follow-up (log rank, p<0.001). The decrease in survival rate during TB treatment remained significant in a multivariate Cox model controlling for human immunodeficiency virus (HIV) status, age and gender, with a mortality increase of 1.19 (95% CI, 1.04-1.36) per microg of sCD163, and a hazard ratio (HR) for sCD163 levels above the upper reference limit of 4.18 (95% CI, 1.06-16.4). The difference was not significant after excluding patients with concomitant HIV-1 and HIV-2 infection in Kaplan-Meier analyses (log rank, p 0.11). In contrast, the difference in survival remained significant in Kaplan-Meier analyses after long-term follow-up, even after excluding patients with concomitant HIV-1 and HIV-2 infection (log rank, p 0.002). In the Cox model, the mortality increase per microg of sCD163 was 1.27 (95% CI, 1.14-1.40), with an HR for elevated sCD163 levels of 2.85 (95% CI, 1.44-5.63). The HRs for concomitant HIV-1 and HIV-2 infection were 6.92 (95% CI, 3.28-14.58) and 2.48 (95% CI, 1.09-5.67), respectively. Thus, sCD163 levels appeared to be an independent predictor of survival in verified TB patients.

Buspirone, a serotonin receptor agonist, increases CD4 T-cell counts and modulates the immune system in HIV-seropositive subjects.

OBJECTIVE: We have previously shown that drugs that decrease intracellular cAMP levels increase/restore the proliferative and cytotoxic capacity of T cells from HIV-seropositive subjects in vitro. Buspirone, a serotonin receptor agonist, indirectly decreases intracellular cAMP levels in T cells and has the same increasing/restoring effect on T-cell proliferation in lymphocytes from HIV-seropositive subjects in vitro. DESIGN: Buspirone was given as a single high dose to six HIV-seropositive subjects, or as continuous medication with increasing dosage over 6 weeks to nine HIV-seropositive subjects, with CD4 T-cell counts of 150-300 x 10(6)/l. RESULTS: Significant increases in CD4 T cells, CD4 percentage and CD4/CD8 ratio were found 1 week after a single high dose of buspirone was administered. With continuous administration, a significant increase in CD4 T cells was observed after 1 and 4 weeks. Serum HIV RNA showed a significant decrease 1 h after a single dose of buspirone was administered. With continuous administration of buspirone, plasma HIV RNA first increased within the first 2 weeks of treatment and then decreased towards and below baseline concurrently with a significant decrease in CD8T cells. The proliferative T-cell response to poke weed mitogen and membrane expression of IL-2R increased significantly during continuous treatment with a significant decrease in expression of HLA-DR on CD8+ T cells. Development of "flu-like' symptoms, so severe that two patients withdrew from the study and two patients ceased medication before time, was a clinical indication of modulation of the immune system by buspirone. CONCLUSION: The study shows that buspirone modulates the immune system and leads to changes in the CD4 and CD8 T-cell numbers, functional capacity, cell maturation and viral load.

Determination of the components of immune complexes made in vitro with antigens derived from Pseudomonas aeruginosa.

A method for identification of the components of immune complexes would increase our understanding of the pathogenesis of chronic diseases such as Pseudomonas aeruginosa lung infection in cystic fibrosis. Capillary tube, gel diffusion and turbidimetric methods of determining immune complex formation were investigated with antigens from P. aeruginosa and the homologous rabbit antisera. Visible complexes were formed in the first two methods with flagella antigens. Purified lipopolysaccharide from P. aeruginosa would not form visible precipitates and a rapid and economical turbidimetric method was developed with 96-well microtiter plates. Larger quantities of immune complexes were formed in vitro with antigen/antibody ratios determined by the above methods. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting (Western blotting) were evaluated and found to be useful in determining the antigen and antibody components of these immune complexes.

Induction of oxidative burst response in human neutrophils by immune complexes made in vitro of lipopolysaccharide and hyperimmune serum from chronically infected patients.

Purified lipopolysaccharide (LPS) from Pseudomonas aeruginosa was used as an antigen for immune complex (IC) formation in vitro together with hyperimmune sera from chronically P. aeruginosa-infected patients with cystic fibrosis (CF). P. aeruginosa LPS by itself did not induce an oxidative burst in human neutrophil granulocytes (PMN)s measured by chemiluminescence (CL). This was also the case using hyperimmune CF serum alone. In contrast, P. aeruginosa LPS together with CF serum did induce a CL response. The CL responses varied depending on the sera used for IC formation, and were reduced when protein A preabsorbed sera were used. PEG precipitation of the ICs from the mixture increased the CL response. These findings indicate that the CL responses induced by the mixture of P. aeruginosa LPS and CF serum were due to IC formation and an Fc-mediated stimulation of the PMNs. It is concluded that ICs made from sera of chronically infected CF patients and purified P. aeruginosa LPS are biologically active in terms of activating PMNs, and may contribute to the lung tissue damage seen in this group of patients.

Lipopolysaccharide is present in immune complexes isolated from sputum in patients with cystic fibrosis and chronic Pseudomonas aeruginosa lung infection.

Sputum samples from seven patients with cystic fibrosis and chronic P. aeruginosa lung infection were investigated for immune complexes by PEG precipitation and in two different complement binding assays. All seven patients were immune complex positive. The components involved in immune complex formation were identified by SDS-PAGE and immunoblotting. We found P. aeruginosa lipopolysaccharide as a major antigen. Both core and O-specific saccharide antigens could be demonstrated. IgG and IgA were the immunoglobulins involved, with IgG2 as the dominating IgG subclass. Lipopolysaccharide has a number of biological activities and its presence in sputum may have consequences for the pathogenesis of lung disease in cystic fibrosis.

Antibodies from chronically infected cystic fibrosis patients react with lipopolysaccharides extracted by new micromethods from all serotypes of Pseudomonas aeruginosa.

Micromethods were developed to extract lipopolysaccharide (LPS, endotoxin) from single bacterial colonies of the 20 recognized Pseudomonas aeruginosa type strains. The appearance of these LPSs in polyacrylamide gel electrophoresis (PAGE) and their reactivity with serum of cystic fibrosis (CF) patients chronically infected with P. aeruginosa was studied. Silver staining of LPS after PAGE showed that 13 of the P. aeruginosa LPSs had high numbers of O-repeating units arranged in 1-4 clusters of banding. Low-molecular-weight LPS fractions were more prominent in six of the serotype strains, of which O:7 and O:14 appeared semi-rough. Corresponding immunoblots using the CF sera showed LPS patterns very similar to the silver-stained appearance, indicating an immune reaction to all P. aeruginosa LPS including that from the newly discovered O:18, O:19 and O:20. This was unexpected since only a few serotype strains (mostly O:3, O:6 and O:9) had been isolated from the patients. Absorption experiments using purified and chemically defined P. aeruginosa rough LPS and smooth LPS suggested these immune reactions were due to antibodies cross-reactive to core/lipid A as well as to lower molecular weight O-polysaccharides or "A-bands". However, in some cases O:3, O:6, and O:9 LPSs were also found to contain additional distinct O-epitopes. Immune recognition of various polyagglutinable P. aeruginosa LPSs seemed also to be caused by cross-reactive antibodies. The described microextraction methods, followed by PAGE and silver staining or immunoblotting, are easy and convenient techniques with which to study antibodies against LPS epitopes and to screen for LPS phenotypic appearance using only a few bacterial colonies from larger numbers of Gram-negative bacterial strains.

The plasma level of soluble urokinase receptor is elevated in patients with Streptococcus pneumoniae bacteraemia and predicts mortality.

This multicentre prospective study was conducted to investigate whether the level of the soluble form of urokinase-type plasminogen activator receptor (suPAR) is elevated during pneumococcal bacteraemia and is of predictive value in the early stage of the disease. Plasma levels of suPAR were increased significantly (median 5.5; range 2.4-21.0 ng/mL) in 141 patients with pneumococcal bacteraemia, compared to 31 healthy controls (median 2.6, range 1.5-4.0 ng/mL, p 0.001). Furthermore, suPAR levels were elevated significantly in patients who died from the infection (n = 24) compared to survivors (n = 117; p < 0.001). No correlation was found between suPAR levels and C-reactive protein. In univariate logistic regression analysis, hypotension, renal failure, cerebral symptoms and high serum concentrations of protein YKL-40 and suPAR were associated significantly with mortality (p < 0.05). In multivariate analysis, only suPAR remained a significant predictor of death (mortality rate of 13 for suPAR levels of > 10 ng/mL; 95% CI: 1.1-158). The increase in suPAR levels may reflect increased expression by vascular or inflammatory cells in the setting of pneumococcal sepsis. This plasma protein may be used to identify patients who are severely ill with pneumococcal bacteraemia.

Cytokines in sputum and serum from patients with cystic fibrosis and chronic Pseudomonas aeruginosa infection as markers of destructive inflammation in the lungs.

The presence of interleukin (IL)-1 receptor antagonist (IRAP) in plasma and sputum from patients with cystic fibrosis (CF) and chronic Pseudomonas aeruginosa lung infection was investigated together with IL-1 alpha, IL-1 beta, IL-6, and tumor necrosis factor-alpha (TNF) in a cross-sectional study. All cytokines were assayed by ELISAs. High concentrations of IRAP, IL-1 alpha, IL-1 beta, IL-6, and TNF in sputum samples and low or nondetectable levels of circulating cytokines were frequently found. Increased concentrations of plasma IRAP are positively correlated with decreasing pulmonary function. In a longitudinal study of serum IRAP, a higher level of IRAP was detected in a group of patients with poor pulmonary function compared to a group with good pulmonary function.

[Is polysaccharide pneumococcal vaccine effective in adults?]. / Er der klinisk effekt af polysakkaridbaseret pneumokokvaccine hos voksne?

Pneumococcal (PC) infections are common and dangerous. Polysaccharide PC vaccine is recommended in some countries for use in adults who have an increased risk of PC infection. Randomised studies of the clinical effect of polysaccharide PC vaccine in healthy adults reported a protective effect, which, in general, was not reproduced in subsequent studies of risk groups. Case-control studies showed a protective effect, but were potentially biased. Two meta-analyses found that the vaccine had an effect on the incidence of PC bacteraemia and pneumonia in healthy adults, but had no effect in risk groups; one meta-analysis found no evidence of less effect in risk groups. There is insufficient evidence to support mass vaccination of risk groups, including elderly people, with polysaccharide PC vaccine.

[Sample size and number needed to treat--a statistical case study]. / Sample size og number needed to treat--en statistisk kasuistik.

The sample size necessary in each group to detect a significant effect of a vaccine on a given disease in a randomised clinical trial (RCT) can be calculated from the observed disease incidence without vaccine, the expected incidence with vaccine, and the desired level of significance and statistical power of the study. In this example, sample size is calculated for an RCT of the effect of pneumococcal vaccine on the incidence of pneumococcal sepsis. The number of persons needed to be vaccinated to prevent one episode of pneumococcal sepsis can be similarly calculated from the observed incidences with and without vaccine.