Evaluation of anamnestic criteria for the identification of patients with acute community onset viral gastroenteritis in the emergency department--A prospective observational study

BACKGROUND

To our knowledge no clinical criteria for the identification of community onset viral gastroenteritis in individual patients have been evaluated systematically with modern PCR-based diagnostic assays as gold standard.

OBJECTIVE

The aim of this study was to identify factors independently associated with the detection of virus by PCR in rectal swab samples from patients with acute community onset gastroenteritis.

METHODS

A prospective observational study was conducted from December 2010 through March 2011 at the emergency department (ED) of a large teaching hospital. All patients who reported vomiting and/or diarrhoea up to 48 h prior to their visit to the ED were asked to participate. A rectal swab sample was obtained from each patient. Symptoms, date of onset, and epidemiological data were recorded. Samples were analysed with a multiple real-time PCR targeting 6 viral agents (astrovirus, adenovirus, rotavirus, sapovirus, and norovirus GI and GII).

RESULTS

Two hundred and five patients fulfilled the inclusion criteria, of whom 66 agreed to participate; their median (IQR) age was 65 (38-84) y and 43 (65%) were females. Thirty-one (47%) were positive by PCR for at least 1 of the agents examined (26 norovirus, 2 sapovirus, 2 rotavirus, and 1 adenovirus). Diarrhoea and a short duration of symptoms (≤ 2 days) were independently associated with a positive rectal swab sample, with odds ratios of 7.5 (95% confidence interval (CI) 2.0-28) and 10.4 (95% CI 1.9-56), respectively (p < 0.01 for both). A multivariate model including these 2 variables had a sensitivity of 81% (25/31) and a specificity of 69% (24/35).

CONCLUSIONS

Diarrhoea and a short duration of symptoms were the only anamnestic criteria independently associated with acute community onset viral gastroenteritis confirmed by PCR.

A novel fibrosis index comprising a non-cholesterol sterol accurately predicts HCV-related liver cirrhosis

Diagnosis of liver cirrhosis is essential in the management of chronic hepatitis C virus (HCV) infection. Liver biopsy is invasive and thus entails a risk of complications as well as a potential risk of sampling error. Therefore, non-invasive diagnostic tools are preferential. The aim of the present study was to create a model for accurate prediction of liver cirrhosis based on patient characteristics and biomarkers of liver fibrosis, including a panel of non-cholesterol sterols reflecting cholesterol synthesis and absorption and secretion. We evaluated variables with potential predictive significance for liver fibrosis in 278 patients originally included in a multicenter phase III treatment trial for chronic HCV infection. A stepwise multivariate logistic model selection was performed with liver cirrhosis, defined as Ishak fibrosis stage 5–6, as the outcome variable. A new index, referred to as Nordic Liver Index (NoLI) in the paper, was based on the model: Log-odds (predicting cirrhosis) = −12.17+ (age×0.11) + (BMI (kg/m²)×0.23) + (D₇-lathosterol (μg/100 mg cholesterol)×(−0.013)) + (Platelet count (x10⁹/L)×(−0.018)) + (Prothrombin-INR×3.69). The area under the ROC curve (AUROC) for prediction of cirrhosis was 0.91 (95% CI 0.86–0.96). The index was validated in a separate cohort of 83 patients and the AUROC for this cohort was similar (0.90; 95% CI: 0.82–0.98). In conclusion, the new index may complement other methods in diagnosing cirrhosis in patients with chronic HCV infection.

The risk of HCV RNA contamination in serology screening instruments with a fixed needle for sample transfer

BACKGROUND

Hepatitis C diagnostics involve antibody screening and confirmation of current infection by detection of HCV RNA positivity. In screening instruments with fixed pipetting needle, there is a risk of sample carry-over contamination.

OBJECTIVES

The aim of this study was to evaluate the risk of such contamination in a proposed clinical setting.

STUDY DESIGN

In the present study, known HCV RNA positive (n=149) and negative (n=149) samples were analysed by anti-HCV Abbott in an Architect instrument in an alternating fashion in order to test for contamination.

RESULTS

In subsequent retesting of the previously HCV RNA-negative samples, six samples (4%) were positive by the Cobas Taqman assay with a maximum level of 33 IU/mL. The results show that there is a risk for transfer of HCV in the Architect instrument but they also show that the levels of HCV RNA observed are low.

CONCLUSIONS

We conclude that complementary HCV RNA testing on samples identified as anti-HCV positive by screening can be recommended because the complementary results are reliable in the majority of cases when either HCV RNA is negative or HCV RNA is positive with a level >1000 IU/mL. In a minority of cases, with low HCV RNA after anti-HCV antibody screening, cross-contamination should be suspected and a new sample requested for HCV RNA testing. This strategy would reduce the need for obtaining a new sample from the vast majority of patients with a newly discovered HCV antibody positivity.

Impact of Il28b-related single nucleotide polymorphisms on liver transient elastography in chronic hepatitis C infection

BACKGROUND AND AIMS

Recently, several genome-wide association studies have revealed that single nucleotide polymorphisms (SNPs) in proximity to IL28B predict spontaneous clearance of hepatitis C virus (HCV) infection as well as outcome following pegylated interferon and ribavirin therapy among genotype 1 infected patients. Additionally the presence of the otherwise favorable IL28B genetic variants in the context of HCV genotype 3 infection reportedly entail more pronounced liver fibrosis and steatosis. The present study aimed to evaluate the impact of IL28B SNP variability on liver stiffness as accessed by transient elastography.

METHODS

Seven hundred and seventy-one Swedish HCV infected patients sequentially undergoing liver stiffness measurement by means of Fibroscan® in the context of a real-life trial had samples available for IL28B genotyping (rs12979860) and HCV genotyping.

RESULTS

CC(rs12979860) was more common among HCV genotype 2 or 3 infected treatment-naïve patients than among those infected with genotype 1 (P<0.0001). Additionally CC(rs12979860) among HCV genotype 3 infected patients was associated with higher liver stiffness values (P = 0.004), and higher AST to platelet ratio index (APRI; p = 0.02) as compared to carriers of the T allele. Among HCV genotype 1 infected patients, CC(rs12979860) was significantly associated with higher viral load (P = 0.001), with a similar non-significant trend noted among HCV genotype 3 infected patients.

CONCLUSION

This study confirms previous reports that the CC(rs12979860) SNP is associated with more pronounced liver pathology in patients chronically infected with HCV genotype 3 as compared to genotype 1, suggesting that IL28B genetic variants differently regulates the course of HCV infection across HCV genotypes.

Comparison of rectal swabs and faeces for real-time PCR detection of enteric agents in Rwandan children with gastroenteritis

Background

Molecular diagnostics have emerged as an efficient and feasible alternative for broad detection of pathogens in faeces. However, collection of stool samples is often impractical in both clinical work and in epidemiology studies. The aim of this study was to investigate the diagnostic performance of rectal swabs as compared with traditional faeces samples for detection of enteric agents by PCR.

Method

Three hundred twenty-six pairs of rectal swab and stool samples, obtained from Rwandan children aged 0.5-4.99 years, with or without diarrhoea, were analysed by multiple real-time PCR amplifying 3 viral, 6 bacterial and one protozoan target.

Results

For all agents there was a significant correlation (R² 0.31-0.85) between Ct values in faeces and rectal swabs. For most agents the Ct values, a marker for target concentration, were significantly lower (by 1–3 cycles) in faeces, indicating pathogen content up to ten times higher than in rectal swabs. Despite this, there was no significant difference in detection rate between faeces and rectal swabs for any agent, reflecting that pathogen concentration was far above the limit of detection in the majority of cases.

Conclusion

The similar detection rates and the Ct value correlations as compared with traditional faeces samples indicate that rectal swabs are accurate for real-time PCR-based identification of enteric agents and may be used also for quantitative estimation of pathogen load.

Retreatment with peg-interferon and ribavirin in patients with chronic hepatitis C virus genotype 2 or 3 infection with prior relapse

OBJECTIVES

Uncertainty remains regarding the efficacy of retreatment with current standard-of-care peg-interferon (peg-IFN) and ribavirin among patients infected with hepatitis C virus (HCV) genotypes 2 or 3 with relapse after prior therapy.

MATERIALS AND METHODS

Seventy-one patients with chronic HCV genotype 2/3 with prior relapse were enrolled in a phase III multicenter study. Patients were retreated with peg-IFNα-2a 180 μg per week and ribavirin 1000/1200 mg daily. Patients having received previous therapy for 24 weeks were retreated for 48 weeks (Group A), whereas patients having received at least 12 weeks but less than 24 weeks of treatment were allocated to either 48 (Group B) or 24 weeks (Group C) on the basis of whether they had achieved rapid virological response (RVR).

RESULTS

Sustained virological response (SVR) rates of 53%, 81% and 75% were achieved in groups A, B and C, respectively. Patients with favorable baseline characteristics, e.g., less advanced liver fibrosis, age <40 years, duration of infection <20 years, or BMI < 25 kg/m(2), tended to have more favorable outcomes. All patients achieving HCV RNA below 1000 IU/mL day 6 achieved SVR in contrast to none of the patients with detectable HCV RNA at week 12.

CONCLUSIONS

Retreatment with peg-IFN and ribavirin for 24-48 weeks entails SVR among the majority of HCV genotype 2/3 infected patients with prior relapse. However, in light of the prolonged treatment duration, moderate effect and considerable side effects, deterring therapy until new options are available may be preferential, particularly in patients previously treated for 24 weeks.

Genetic diversity of genotype D3 in acute hepatitis B

Acute hepatitis B related to injection drug use is often caused by HBV-D3, a subgenotype that probably was introduced in Western Europe in the 1960s. The aim of this study was to describe genetic change over time in injection drug use-related HBV-D3 in one geographic area. Fourteen complete genomes and partial genomic regions of 17 HBV strains of subgenotype D3 causing acute (n = 30) or chronic (n = 1) hepatitis B at different time points between 1975 and 2009 were investigated. The 14 complete genomes clustered in phylogenetic trees on a sub-branch of HBV-D3 along with a few published sequences with high bootstrap values. In contrast, the phylogenetic tree topology based on nucleotides coding for surface antigen or core was uncertain with bootstrap values below 70% or lower. Variation of nucleotides coding for amino acids 125, 136, and 143 in the a determinant of HBsAg was however linked to complete genome phylogeny, indicating that these codons might be useful as markers for clades. The results show that knowledge about circulating strains is critical for the interpretation of molecular epidemiology investigations. The low degree of genetic change over time of HBV-D3 in the studied groups suggests that outbreaks of acute hepatitis B in injection drug users might originate from a limited number of individuals with chronic infection. Classification based on core or S region phylogeny obtained poor support from bootstrap values, but the presence of clade-specific amino acid substitutions suggests that the S region may be useful for subgenomic molecular epidemiology of HBV.

Dynamic tailoring of treatment durations improves efficiency of hepatitis C treatment with pegylated interferon and ribavirin

The treatment durations for hepatitis C are guided by the analysis of hepatitis C virus (HCV) RNA in blood at certain time points. This multicentre, randomized open label trial evaluated the utility and performance of individualized treatment durations guided by viral decline rates in 103 patients with HCV genotype 1 infection. Pegylated interferon 2a and ribavirin were given as standard of care (SOC) for 24, 48 or 72 weeks or as dynamic treatment (DT) for 24-72 weeks. The DT duration was based on the time point when log HCV RNA would reach 0 log copies/mL, as estimated by the second-phase decline. The rate of sustained virologic response was 63% for SOC and 54% for DT, but this difference was not significant in multiple regression analysis taking predictive factors such as interleukin-28B genotypes, age and baseline viremia into account (P = 0.45). The mean required treatment time per cured patient was 51 weeks for DT as compared with 58 weeks for SOC (P = 0.22) when given per protocol (n = 95) and was significantly shorter (42 vs 51 weeks) among patients who achieved undetectable HCV RNA (P = 0.01). We conclude that DT was feasible and increased efficiency. The estimated time point for 0 log viral copies/mL is a new and quantitative response variable, which may be used as a complement to the qualitative variable rapid virologic response. The outcome parameter treatment weeks per cured patient could become a useful tool for comparing treatment efficiency also in the era of directly acting antivirals.

Rhinovirus infections in western Sweden: a four-year molecular epidemiology study comparing local and globally appearing types

Human rhinovirus (HRV) is a highly prevalent pathogen and a major cause of acute respiratory tract infection (ARTI). HRV express less seasonality than other viral ARTIs, which typically appear as seasonal epidemics lasting for 1–2 months. The aim of this study was to investigate the seasonal patterns of HRV types over four consecutive years in one geographic region. HRV identified in respiratory samples from 114 patients over a four-year period were analysed by VP4/VP2 sequencing. HRV-A was found in 64, HRV-B in 11 and HRV-C in 37 cases. Overall, 33 different HRV-A types, nine B types and 21 C types were found. As many as 21 of the HRV types appeared during several seasons, with a maximum time-span of four years. Some types appeared during successive seasons and, in some cases, phylogenetic analysis indicated extended periods of circulation locally. Most of the strains were closely related to HRV identified in other parts of the world during the same time period. HRV strains that circulate locally represent many types and seem to reflect that HRV infections are highly globalised. The existence of simultaneous or successive epidemics with different HRV types in combination with the ability of each type to remain in the local population over extended periods of time may contribute to explaining the high rate of HRV infections.

Impact of soluble CD26 on treatment outcome and hepatitis C virus-specific T cells in chronic hepatitis C virus genotype 1 infection

Background

Interferon and ribavirin therapy for chronic hepatitis C virus (HCV) infection yields sustained virological response (SVR) rates of 50–80%. Several factors such as non-1 genotype, beneficial IL28B genetic variants, low baseline IP-10, and the functionality of HCV-specific T cells predict SVR. With the pending introduction of new therapies for HCV entailing very rapid clearance of plasma HCV RNA, the importance of baseline biomarkers likely will increase in order to tailor therapy. CD26 (DPPIV) truncates the chemokine IP-10 into a shorter antagonistic form, and this truncation of IP-10 has been suggested to influence treatment outcome in patients with chronic HCV infection patients. In addition, previous reports have shown CD26 to be a co-stimulator for T cells. The aim of the present study was to assess the utility of CD26 as a biomarker for treatment outcome in chronic hepatitis C and to define its association with HCV-specific T cells.

Methods

Baseline plasma from 153 genotype 1 and 58 genotype 2/3 infected patients enrolled in an international multicenter phase III trial (DITTO-HCV) and 36 genotype 1 infected patients participating in a Swedish trial (TTG1) were evaluated regarding baseline soluble CD26 (sCD26) and the functionality of HCV-specific CD8⁺ T cells.

Results

Genotype 1 infected patients achieving SVR in the DITTO (P = 0.002) and the TTG1 (P = 0.02) studies had lower pretreatment sCD26 concentrations compared with non-SVR patients. Sixty-five percent of patients with sCD26 concentrations below 600 ng/mL achieved SVR compared with 39% of the patients with sCD26 exceeding 600 ng/mL (P = 0.01). Patients with sCD26 concentrations below 600 ng/mL had significantly higher frequencies of HCV-specific CD8⁺ T cells (P = 0.02).

Conclusions

Low baseline systemic concentrations of sCD26 predict favorable treatment outcome in chronic HCV infection and may be associated with higher blood counts of HCV-specific CD8⁺ T cells.

PNPLA 3 I148M genetic variant associates with insulin resistance and baseline viral load in HCV genotype 2 but not in genotype 3 infection

Background

Hepatic steatosis in HCV patients has been postulated as a risk factor associated with a higher frequency of fibrosis and cirrhosis. A single genetic variant, PNPLA3 I148M, has been widely associated with increased hepatic steatosis. Previous studies of the PNPLA3 I148M sequence variant in HCV infected individuals have reported an association between this variant and prevalence of steatosis, fibrosis, and cirrhosis. To evaluate the impact of PNPLA3 I148M variant on metabolic traits and treatment response in HCV genotype 2 and 3 infected patients.

Methods

Three hundred and eighty-two treatment naïve HCV genotype 2 or 3 infected patients were included in a phase III, open label, randomized, multicenter, investigator-initiated trial (the NORDynamIC study), in which pretreatment liver biopsies were mandatory. PNPLA3I148M genotyping was performed in a total of 359 Caucasian patients.

Results

In HCV genotype 2 infected patients carrying the PNPLA3 148M allele, there was significantly increased insulin resistance (P = 0.023) and lower viral load (P = 0.005) at baseline as well as the first seven days of antiviral treatment. These results were not observed in HCV genotype 3 infected patients.

Conclusions

Our results suggest a possible association between the PNPLA3 148M allele and insulin resistance as well as baseline viral load in HCV genotype 2, but not in genotype 3.

Venous lactate levels can be used to identify patients with poor outcome following community-onset norovirus enteritis

BACKGROUND

Norovirus enteritis (NVE) can be fatal in frail patients. High blood lactate levels indicate hypoperfusion and predict mortality in many infectious diseases. The objective was to determine the frequency and association with mortality of elevated lactate levels in patients with community-onset NVE.

METHODS

A retrospective cohort study was performed. All hospitalized adult patients with community-onset NVE verified by polymerase chain reaction during the period August 2008 to June 2009 were included. Vital signs and venous lactate on arrival, co-morbid conditions, and time of death were registered. The outcome measure was 30-day all-cause mortality.

RESULTS

Eighty-two patients with a median age of 77 y (interquartile range (IQR) 53-86 y) were included, of whom 47 (57%) were female and 49 (60%) had at least 1 major co-morbid condition. Lactate levels were above the upper limit of normal (ULN; 1.6 mmol/l) in 45 patients (55%). The overall 30-day mortality rate was 7% (6/82). Mortality was 18% (5/28) with lactate ≥ 2.4 mmol/l (> 50% above the ULN) on admission compared to 2% (1/54) with lactate < 2.4 mmol/l (p < 0.05). Patients who died had a higher median lactate level compared to survivors: 4.5 (IQR 2.7-7.9) mmol/l vs 1.7 (IQR 1.3-2.5) mmol/l, respectively (p < 0.01). The adjusted odds ratio for death within 30 days for a 1 mmol/l increase in lactate was 2.5 (95% confidence interval 1.003-6.3, p = 0.049).

CONCLUSIONS

We observed a high proportion of patients with elevated lactate levels in community-onset NVE. Lactate elevation could predict mortality. Measurement of blood lactate may be a valuable tool in the clinical management of patients with a suspected norovirus infection.

Hepatitis B viral DNA decline at loss of HBeAg is mainly explained by reduced cccDNA load--down-regulated transcription of PgRNA has limited impact

Background

Quantification of hepatitis B virus (HBV) DNA and surface antigen (HBsAg) serum levels have become increasingly important for the assessment of clinical stage and response to treatment for chronic hepatitis B. Effective immune clearance results in reduction of viremia by 4–5 log units and HBsAg levels by 2 log, but these processes are not well understood. Thus, it is uncertain to what extent mechanisms that inhibit transcription of the pregenomic RNA (pgRNA), an RNA intermediate, contribute to suppression of viremia. Likewise, it is unclear if transcriptional regulation is important for the excessive production of surface antigen (HBsAg) that is a hallmark of HBV infection.

Methods

HBV RNA and cccDNA were quantified in 19 liver biopsies from patients with chronic HBV infection, as well as in transfected Huh7.5 cells and in PLC/PRF/5 cells carrying integrated HBV genome.

Results

Patients negative for HBeAg had 2.15 log lower levels of cccDNA in liver tissue, 4.84 log lower serum levels of HBV DNA and 1.45 log lower serum levels of HBsAg, than HBeAg-positive patients. The pgRNA in liver tissue correlated strongly with cccDNA (R² = 0.87, p<0.0001) and HBV DNA levels in serum (R² = 0.81, p<0.0001), whereas S-RNA correlated strongly with cccDNA (R² = 0.65, p<0.0001) and HBsAg levels (R² = 0.57, p = 0.0003). The S-RNA/pgRNA ratio was higher in HBeAg-negative patients (ratio 40 vs. 3, p = 0.01) and in PLC/PRF/5 cells, and was in transfected Huh7.5 cells not influenced by mutations in the HBV core promoter.

Conclusion

The reduction of viremia that is observed after loss of HBeAg was mainly explained by reduced cccDNA load in the liver, whereas the contribution of down-regulation of pgRNA transcription was relatively small. Enhanced transcription of S-RNA does not explain excessive production of HBsAg.

Treatment of hepatitis C virus infection in adults and children: updated Swedish consensus recommendations

Swedish recommendations for the treatment of hepatitis C virus (HCV) infection were updated at a recent expert meeting. Therapy for acute HCV infection should be initiated if spontaneous resolution does not occur within 12 weeks. The recommended standard-of-care therapy for chronic HCV genotype 1 infection is an HCV protease inhibitor in combination with peginterferon (peg-IFN) and ribavirin. Treatment is strongly recommended in patients with bridging fibrosis and cirrhosis, whereas in patients with less advanced fibrosis, deferring therapy may be preferential in light of likely therapeutic improvements in the near future. Patients with chronic genotype 2/3 infection should generally be treated with peg-IFN and ribavirin for 24 weeks. In patients with a very rapid viral response (i.e. HCV RNA below 1000 IU/ml on day 7), or favourable baseline characteristics and undetectable HCV RNA week 4, treatment can be shortened to 12-16 weeks, provided that no dose reductions are needed.

Type-dependent E6/E7 mRNA expression of single and multiple high-risk human papillomavirus infections in cervical neoplasia

BACKGROUND

Coinfection with multiple HPV types is common in cervical lesions, but the biological significance of the individual infections is difficult to establish. Expression of oncogenic E6/E7 HPV mRNA is correlated to risk of malignant progression, commercial assays for genotyping E6/E7 mRNA of all HR-HPV are lacking.

OBJECTIVES

To characterize the tendency of 12 HR-HPV to express mRNA, correlated to the severity of the cervical lesion. Furthermore, we wanted to analyse mRNA expression in multiple infections, in order to establish which genotype may be responsible for cellular transformation.

STUDY DESIGN

245 samples from women with normal histology, various grades of dysplasia (cervical intraepithelial neoplasia grade 1-3), and cancer, were analysed for presence and genotyping of HPV DNA and mRNA using an in house real-time PCR test.

RESULTS

Presence of mRNA was detected for 64% of the in total 422 HPV infections present in the samples, and more commonly in high-grade lesions. In 88% of DNA-positive samples from CIN2+ lesions, mRNA could be detected, compared to 33% of DNA-positive samples from women in screening with normal cytology. The genotype most prone to express mRNA in high-grade lesions was HPV45, followed by HPV16 and HPV31, less prone was HPV59. Expression of mRNA was significantly enhanced in CIN2+ lesions, an association also found for HPV16. In 52% of multiple infections (in which mRNA expression was generally more common), more than one genotype expressed mRNA, a phenomenon increasing with severity of lesion. Presence of mRNA could more often be detected in samples with multiple infections than in samples with single infections.

CONCLUSIONS

The frequent expression of E6/E7 by HPV45 may promote oncogenicity and could be of clinical importance. Since presence of E6/E7 mRNA was common in multiple infections regardless of histology, multiple infection could be a clinically important finding. In multiple HPV infections, mRNA testing may identify the genotype that causes transformation. However, since mRNA expression of several genotypes in one sample is common, further and larger studies using complementary techniques are required.

Enteric viruses in healthy children in Cameroon: viral load and genotyping of norovirus strains

Data regarding prevalence of noroviruses (NoVs) among asymptomatic persons are scarce. The current study carried out on samples from Cameroon describes the asymptomatic shedding of NoVs and other enteric viruses in healthy children and in adults infected with HIV but lacking symptoms of gastroenteritis. Enteric viruses were common with a prevalence of 53.7% in the children, and 35.5% in the adult participants. Multiple enteric viruses (2-5 agents) were detected in fecal samples from 65% of the children, and co-infection with NoV was demonstrated in almost all cases of multiple infections. NoV viral loads in the healthy children were within disease causing range and significantly higher than those observed in the adults (P < 0.01). Sequencing and genotyping of NoV strains by phylogeny showed a marked diversity within two distinct genogroups, GI and GII, and strains clustered with genotypes GI.3, GII.17, GII.8, and GII.4. Genetic similarities to recent outbreak strains from other continents suggest a rapid circulation of NoVs that includes healthy children, who may constitute a reservoir for pathogenic NoVs.

Impact of IL28B-related single nucleotide polymorphisms on liver histopathology in chronic hepatitis C genotype 2 and 3

BACKGROUND AND AIMS

Recently, several genome-wide association studies have revealed that single nucleotide polymorphisms (SNPs) in proximity to IL28B predict spontaneous clearance of HCV infection as well as outcome following peginterferon and ribavirin therapy among HCV genotype 1 infected patients. The present study aimed to evaluate the impact of IL28B SNP variability on liver histology in the context of a phase III treatment trial (NORDynamIC) for treatment-naïve patients with chronic HCV genotype 2 or 3 infection, where pretreatment liver biopsies were mandatory.

METHODS

Three hundred and thirty-nine Caucasian patients had samples available for IL28B genotyping (rs12979860) of whom 314 had pretreatment liver biopsies that were evaluated using the Ishak protocol, allowing for detailed grading and staging of liver histopathology.

RESULTS

IL28B CC(rs12979860) genotype in HCV genotype 3 infected patients was associated with higher ALT levels (p<0.0001), higher AST to platelet ratio index (APRI; p = 0.001), and higher baseline viral load (p<0.0001) as compared to patients with the CT or TT genotypes. Additionally the CC(rs12979860) genotype entailed more pronounced portal inflammation (p = 0.02) and steatosis (p = 0.03). None of these associations were noted among HCV genotype 2 infected patients.

CONCLUSION

This study shows that the CC(rs12979860) SNP is associated with more pronounced liver histopathology in patients chronically infected with HCV genotype 3, which may be secondary to higher viral load. The finding that IL28B variability did not impact on liver pathology or viral load among genotype 2 infected patients implies that IL28B may differentially regulate the course of genotype 2 and 3 infection.

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

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.