Lars-Magnus Andersson

Increased blood-brain barrier permeability in neuro-asymptomatic HIV-1-infected individuals—correlation with cerebrospinal fluid HIV-1 RNA and neopterin levels

The objective of this study was to assess the frequency of blood-brain barrier (BBB) impairment, as measured by the albumin ratio, in neuro-asymptomatic HIV-1-infected individuals without antiretroviral treatment and the correlation between BBB disruption and intrathecal immune activation and HIV-1 RNA levels. Serum and cerebrospinal fluid (CSF) albumin, neopterin, and HIV-1 RNA levels were analysed in 110 neuro-asymptomatic HIV-1-infected individuals at different stages of disease; 63 classified as CDC A, 25 as CDC B, and 22 as CDC C. Increased BBB permeability was found in 17 of 110 (15%) of HIV-1-infected individuals. This proportion was sustained throughout the CDC stages. The albumin ratio was correlated with the CSF neopterin levels (rs = 0.36, P < 0.001), the serum neopterin levels (rs = 0.37, P < 0.001), and the CSF HIV-1 RNA levels (rs = 0.26, P < 0.01), but not with the plasma HIV-1 RNA levels. The correlations between the albumin ratio and the CSF and serum neopterin concentrations and the CSF HIV-1 RNA levels indicate that immune activation and, possibly, intrathecal HIV-1 virus replication are important factors associated with increased BBB permeability in HIV-1 infection.

Seasonal variations of 15 respiratory agents illustrated by the application of a multiplex polymerase chain reaction assay

Abstract Background: Nucleic acid amplification tests are increasingly being used to diagnose viral and bacterial respiratory tract infections. The high sensitivity of these tests affects our understanding of the epidemiology of respiratory tract infections. We have assessed the detection rate of a multiplex real-time polymerase chain reaction (PCR) test, with emphasis on epidemiology and seasonal distribution of the most common respiratory tract infections. Methods: Seven thousand eight hundred and fifty-three nasopharyngeal samples from 7220 patients (age range 0–98 y, median 22 y) obtained during 36 consecutive months (November 2006–October 2009), were analyzed with a multiplex PCR panel including influenza A (IfA) and B (IfB) virus, parainfluenza virus (PIV) 1–3, respiratory syncytial virus (RSV), human rhinovirus (HRV), human coronavirus (CoV) OC43, NL63, and 229E, human metapneumovirus (HMPV), adenovirus (AdV), enterovirus (EV), and 2 bacteria – Mycoplasma pneumoniae and Chlamydophila pneumoniae. Results: Of the total samples, 44.5% (n = 3496) were positive for at least 1 agent, with HRV being the most common (n = 1482, 38.0%), followed by RSV (n = 526, 13.5%) and IfA (n = 403, 10.3%). The diagnostic yield was significantly higher during the winter and early spring compared to the summer (n = 2439 of 4458 samples, 54.7% and n = 1057 of 3395 samples, 31.1%, respectively; p < 0.001). Conclusions: The diagnostic yield was highly dependent on the month of sampling and the age of the patient. However, the overall detection rate per month was above 30%, apart for August and September. Our findings support the use of similar tests in routine clinical care all year round. HRV was the most common finding in the respiratory tract, independent of season.

Increased cerebrospinal fluid protein tau concentration in neuro-AIDS.

OBJECTIVES Assessment of cerebrospinal fluid (CSF) levels of protein tau in human immunodeficiency virus type 1 (HIV-1) infection. MATERIAL AND METHODS CSF tau levels were analyzed in 52 HIV-1-infected patients, 37 of whom had no neurological symptoms, eight had aquired immunodeficiency syndrome (AIDS) dementia complex (ADC), and seven had AIDS with other neurological complications. RESULTS A significantly higher mean CSF tau concentration was found in patients with ADC (380 pg/ml) compared with patients with neuroasymptomatic HIV-1 infection (120 pg/ml, P<0.01) and HIV-negative controls (150 pg/ml, P<0.05). No difference in CSF tau levels was found between patients with ADC and patients with AIDS with other neurological complications. CONCLUSION CSF tau might be used as a biochemical marker for axonal degeneration and might be of use to identify HIV-1-infected patients with ADC and other neurological complications, but it cannot discriminate between ADC and other neurological complications in HIV-1-infection.

Access to a polymerase chain reaction assay method targeting 13 respiratory viruses can reduce antibiotics: a randomised, controlled trial

BackgroundViral respiratory infections are common worldwide and range from completely benign disease to life-threatening illness. Symptoms can be unspecific, and an etiologic diagnosis is rarely established because of a lack of suitable diagnostic tools. Improper use of antibiotics is common in this setting, which is detrimental in light of the development of bacterial resistance. It has been suggested that the use of diagnostic tests could reduce antibiotic prescription rates. The objective of this study was to evaluate whether access to a multiplex polymerase chain reaction (PCR) assay panel for etiologic diagnosis of acute respiratory tract infections (ARTIs) would have an impact on antibiotic prescription rate in primary care clinical settings.MethodsAdult patients with symptoms of ARTI were prospectively included. Nasopharyngeal and throat swabs were analysed by using a multiplex real-time PCR method targeting thirteen viruses and two bacteria. Patients were recruited at 12 outpatient units from October 2006 through April 2009, and samples were collected on the day of inclusion (initial visit) and after 10 days (follow-up visit). Patients were randomised in an open-label treatment protocol to receive a rapid or delayed result (on the following day or after eight to twelve days). The primary outcome measure was the antibiotic prescription rate at the initial visit, and the secondary outcome was the total antibiotic prescription rate during the study period.ResultsA total sample of 447 patients was randomised. Forty-one were excluded, leaving 406 patients for analysis. In the group of patients randomised for a rapid result, 4.5% (9 of 202) of patients received antibiotics at the initial visit, compared to 12.3% (25 of 204) (P = 0.005) of patients in the delayed result group. At follow-up, there was no significant difference between the groups: 13.9% (28 of 202) in the rapid result group and 17.2% (35 of 204) in the delayed result group (P = 0.359), respectively.ConclusionsAccess to a rapid method for etiologic diagnosis of ARTIs may reduce antibiotic prescription rates at the initial visit in an outpatient setting. To sustain this effect, however, it seems necessary to better define how to follow and manage the patient according to the result of the test, which warrants further investigation.Trial registrationClinicalTrials.gov identifier: NCT01133782.

Rectal swabs can be used for diagnosis of viral gastroenteritis with a multiple real-time PCR assay

BACKGROUND Viral agents, especially norovirus, are the most common cause of nosocomial spread of epidemic gastroenteritis (GE). Rapid and reliable detection of these agents could reduce the risk of outbreaks. OBJECTIVE To evaluate the diagnostic performance of rectal swab samples compared to standard stool samples for detection of agents causing viral GE by PCR. STUDY DESIGN Complete pairs of rectal swab and stool samples, obtained simultaneously from patients with symptoms of acute onset GE, were analysed with a multiple real-time PCR targeting six different gastroenteritis agents (astro-, adeno-, rota-, sapo- and norovirus GI and II). Cycle threshold (Ct) values were registered for positive samples. A positive PCR result in either sample for any virus was considered gold standard. RESULTS 69 sample pairs were included of which 29 were negative in both sample types and 38 were positive in both sample types. One pair was positive in the stool sample only and another pair was positive in the rectal swab sample only. Sensitivity for both sample types was 97.5% (39/40). CONCLUSION Rectal swab samples are as reliable as stool samples for PCR-based diagnosis of viral gastroenteritis in patients with a short duration of symptoms and may be used as a complement to stool samples, especially when immediate sampling is desirable.

Norovirus GII.4 Detection in Environmental Samples from Patient Rooms during Nosocomial Outbreaks

ABSTRACT Norovirus (NoV) is an important cause of nosocomial gastroenteric outbreaks. This 5-month study was designed to characterize NoV contamination and airborne dispersal in patient rooms during hospital outbreaks. Air vents, overbed tables, washbasins, dust, and virus traps designed to collect charged particles from the air were swabbed to investigate the possibility of NoV contamination in patient rooms during outbreaks in seven wards and in an outbreak-free ward. Symptomatic inpatients were also sampled. Nucleic acid extracts of the samples were examined for NoV RNA using genogroup I (GI) and GII real-time reverse transcription-PCR (RT-PCR). The NoV strains were characterized by RT-PCR, sequencing, and phylogenetic analysis of the RNA-dependent RNA-polymerase-N/S capsid-coding region (1,040 nucleotides [nt]). Patient strains from two outbreaks in one ward were sequenced across the RNA-dependent-RNA-polymerase major capsid-coding region (2.5 kb), including the hypervariable P2 domain. In the outbreak wards, NoV GII was detected in 48 of 101 (47%) environmental swabs and 63 of 108 patients (58%); NoV genotype II.4 was sequenced from 18 environmental samples, dust (n = 8), virus traps (n = 4), surfaces (n = 6), and 56 patients. In contrast, NoV GII was detected in 2 (GII.4) of 28 (7%) environmental samples and in 2 (GII.6 and GII.4) of 17 patients in the outbreak-free ward. Sequence analyses revealed a high degree of similarity (>99.5%, 1,040 nt) between NoV GII.4 environmental and patient strains from a given ward at a given time. The strains clustered on 11 subbranches of the phylogenetic tree, with strong correlations to time and place. The high nucleotide similarity between the NoV GII.4 strains from patients and their hospital room environment provided molecular evidence of GII.4 dispersal in the air and dust; therefore, interventional cleaning studies are justified.

Excess mortality following community-onset norovirus enteritis in the elderly

Norovirus has been associated with excess deaths. A retrospective study of mortality following norovirus enteritis (NVE) was undertaken. All hospitalized adult patients with a stool sample positive for norovirus genogroup II on polymerase chain reaction, treated at Sahlgrenska University Hospital, Gothenburg, Sweden between August 2008 and June 2009, were included as cases (N = 598, aged 18-101 years). Matched controls without enteritis (N = 1196) were selected for comparison. Medical records were reviewed and deaths up to 90 days following positive sampling were noted, as well as comorbidities and length of hospital stay. Thirty- and 90-day survival rates were calculated. Total 30-day mortality was 7.6% and no deaths were recorded in cases aged 18-59 years. Thirty-day mortality was higher in cases with underlying medical conditions compared with those without these comorbidities (age 60-101 years: 89.5% vs 94.7% alive at Day 30, respectively; P < 0.05). In cases aged > 80 years, mortality was higher in those with community-onset NVE (N = 64) compared with hospital-onset NVE (N = 305) (81.2% vs 90.2% alive at Day 30, respectively; P < 0.05), and compared with controls (N = 128) (81.2% vs 91.4% alive at Day 30, respectively; P < 0.05). Median length of hospital stay was 20 [interquartile range (IQR) 12-29] days for cases with hospital-onset NVE, and seven (IQR 2-13) days for controls (P < 0.001). In conclusion, community-onset NVE requiring hospitalization was associated with higher mortality compared with hospital-onset NVE and matched controls in hospitalized elderly patients.

Kinetics of microbial translocation markers in patients on efavirenz or lopinavir/r based antiretroviral therapy.

Objectives We investigated whether there are differences in the effects on microbial translocation (MT) and enterocyte damage by different antiretroviral therapy (ART) regimens after 1.5 years and whether antibiotic use has impact on MT. In a randomized clinical trial (NCT01445223) on first line ART, patients started either lopinavir/r (LPV/r) (n = 34) or efavirenz (EFV) containing ART (n = 37). Lipopolysaccharide (LPS), sCD14, anti-flagellin antibodies and intestinal fatty acid binding protein (I-FABP) levels were determined in plasma at baseline (BL) and week 72 (w72). Results The levels of LPS and sCD14 were reduced from BL to w72 (157.5 pg/ml vs. 140.0 pg/ml, p = 0.0003; 3.13 ug/ml vs. 2.85 ug/ml, p = 0.005, respectively). The levels of anti-flagellin antibodies had decreased at w72 (0.35 vs 0.31 [OD]; p<0.0004), although significantly only in the LPV/r arm. I-FABP levels increased at w72 (2.26 ng/ml vs 3.13 ng/ml; p<0.0001), although significantly in EFV treated patients only. Patients given antibiotics at BL had lower sCD14 levels at w72 as revealed by ANCOVA compared to those who did not receive (Δ = −0.47 µg/ml; p = 0.015). Conclusions Markers of MT and enterocyte damage are elevated in untreated HIV-1 infected patients. Long-term ART reduces the levels, except for I-FABP which role as a marker of MT is questionable in ART-experienced patients. Why the enterocyte damage seems to persist remains to be established. Also antibiotic usage may influence the kinetics of the markers of MT. Trial Registration ClinicalTrials.gov NCT01445223

Clinical Application of Cerebrospinal Fluid Neopterin Concentrations in HIV Infection

Abstract HIV-1 infects the central nervous system (CNS) and may cause AIDS dementia complex (ADC) and other neurologic complications. The cerebrospinal fluid (CSF) virus load is usually 0,5 -1 log lower than in blood, but in some patients the CSF quantitative HIV-1 RNA values exceed the paired blood samples. CSF neopterin concentrations are increased in all stages of HIV-1 infection, with the highest concentrations in AIDS patients and patients with CNS opportunistic infections. CD4 cell count and quantitative HIV RNA PCR tests in peripheral blood are used in clinical practice to monitor the HIV-1 infection and the anti-retroviral treatment effect. In most patients the anti-retroviral treatment response is similar in the cerebrospinal fluid (CSF) compare to the peripheral blood and the CSF viral load and neopterin concentrations are markedly reduced following treatment. ADC has become a rare complication. In spite of virological effective treatment many patients have a low grade intrathecal immunoactivation, measured as CSF neopterin concentrations above the 95% confidence interval found in IIIV-1 negative controls, after such a long time as after 2 years of anti-retroviral treatment. The risk of long term intrathecal immunoactivation and which anti-retroviral combination treatment has the best effect on CSF parameters is not known. CSF neopterin concentrations are at present not used in clinical practice but may add valuable information.

Differential Effects of Efavirenz, Lopinavir/r, and Atazanavir/r on the Initial Viral Decay Rate in Treatment Naïve HIV-1–Infected Patients

Initial viral decay rate may be useful when comparing the relative potency of antiretroviral regimens. Two hundred twenty-seven ART-naïve patients were randomized to receive efavirenz (EFV) (n = 74), lopinavir/ritonavir (LPV/r) (n = 77), or atazanavir/ritonavir (ATV/r) (n = 79) in combination with two NRTIs. The most frequently used NRTI combinations in the EFV and ATV/r groups were the nonthymidine analogues tenofovir and emtricitabine or lamivudine (70% and 68%, respectively) and, in the LPV/r group, lamivudine and the thymidine analogue zidovudine (89%). HIV-1 RNA was monitored during the first 28 days after treatment initiation. Phase 1 and 2 decay rate was estimated in a subset of 157 patients by RNA decrease from days 0 to 7, and days 14 to 28. One-way ANOVA and subsequent Tukeys post hoc tests were used for groupwise comparisons. Mean (95% CI) HIV-1 RNA reductions from days 0 to 28 were 2.59 (2.45-2.73), 2.42 (2.27-2.57), and 2.13 (2.01-2.25) log(10) copies/ml for the EFV-, LPV/r-, and ATV/r-based treatment groups, respectively, with a significantly larger decrease in the EFV-based group at all time points compared with ATV/r (p < 0.0001), and with LPV/r at days 7-21 (p < 0.0001-0.03). LPV/r gave a greater RNA decrease compared with ATV/r from day 14 (p = 0.02). Phase 1 decay rate was significantly higher in the EFV group compared with LPV/r (p = 0.003) or ATV/r (p < 0.0001). No difference was found in phase 2 decrease. EFV-based treatment gave a more rapid decline in HIV-1 RNA than did either of the boosted protease inhibitor-based regimens. The observed differences may reflect different inherent regimen potencies.