Clinical evaluation of droplet digital pcr for suspected ascites infection in patients with liver cirrhosis.

BACKGROUND: Droplet digital PCR (ddPCR) is increasingly used in diagnosing clinical pathogens, but its effectiveness in cirrhosis patients with suspected ascites infection remains uncertain. METHODS: The diagnostic performance of ddPCR was assessed in 305 ascites samples, utilizing culture and clinical composite standards. The quantitative value and potential clinical impact of ddPCR were further analyzed in patients with spontaneous bacterial peritonitis. RESULTS: With culture standards, ddPCR demonstrated a sensitivity of 86.5% and specificity of 83.2% for bacterial or fungal detection. After adjustment of clinical composite criteria, specificity increased to 96.4%. Better diagnostic performance for all types of targeted pathogens, particularly fungi, was observed with ddPCR compared to culture, and more polymicrobial infections were detected (30.4% versus 5.7%, p < 0.001). Pathogen loads detected by ddPCR correlated with white blood cell count in ascites and blood, as well as polymorphonuclear cell (PMN) count in ascites, reflecting infection status rapidly. A positive clinical impact of 55.8% (43/77) was observed for ddPCR, which was more significant among patients with PMN count ≤ 250/mm3 in terms of medication adjustment and new diagnosis. ddPCR results for fungal detection were confirmed by clinical symptoms and other microbiological tests, which could guide antifungal therapy and reduce the risk of short-term mortality. CONCLUSIONS: ddPCR, with appropriate panel design, has advantages in pathogen detection and clinical management of ascites infection, especially for patients with fungal and polymicrobial infections. Patients with atypical spontaneous bacterial peritonitis benefited more from ddPCR.

Clinical Evaluation of Metagenomic Next-Generation Sequencing Method for the Diagnosis of Suspected Ascitic Infection in Patients with Liver Cirrhosis in a Clinical Laboratory.

Metagenomic next-generation sequencing (mNGS), mostly carried out in independent clinical laboratories, has been increasingly applied in clinical pathogen diagnosis. We aimed to explore the feasibility of mNGS in clinical laboratories and analyze its potential in the diagnosis of infectious ascites. Two reference panels composed of 12 strains commonly appearing in peritonitis were constructed to evaluate the performance metrics based on in-house mNGS protocols. The mNGS clinical detection value was analyzed in 211 ascitic samples and compared with culture and composite standards. Finally, eight patients with cirrhosis were prospectively enrolled to verify the clinical value of mNGS in peritoneal infection diagnosis. The mNGS analytical performance showed that the assay had great linearity, specificity, stability, interference, and limits of detection of 33 to 828 CFU/mL. The sensitivity and specificity of mNGS for bacterial or fungal detection using culture standards were 84.2% and 82.0%, respectively. After adjustment using digital PCR and clinical judgment, the sensitivity and specificity increased to 87.2% and 90.1%, respectively. Compared with culture, mNGS detected a broad range of pathogens and more polymicrobial infections (49% versus 9%, P < 0.05). The pathogen results were obtained within 24 h using mNGS in eight prospective cases, which effectively guided antibiotics therapy. mNGS testing in clinical laboratories affiliated with a hospital has certain advantages. It has unique superiority in pathogens detection, particularly in patients with polymicrobial infections. However, considering spectrum characteristics and test cost, pertinent pathogen panels should be developed in clinical practice. IMPORTANCE This study established and evaluated a complete metagenomics next-generation sequencing assay to improve the diagnosis of suspected ascitic infection in a clinical laboratory affiliated with a hospital. The assay is superior to traditional culture testing and will aid in the early and accurate identification of pathogens, particularly in patients with polymicrobial infections. This assay is also essential for precision therapy and can reduce the incidence of drug resistance stemming from irrational use of antibiotics.

[Comparison of fluorescence quantitative PCR and direct PCR sequencing in the detection of HBV polymerase RT region].

OBJECTIVE: To explore the feasibility of Direct PCR sequencing in clinic and the significance of Direct PCR sequencing for retrieval treatment plan. METHODS: To address this issue, a cross-sectional study on the drug resistance in the HBV polymerase RT region was performed using Fluorescence quantitative PCR and Direct PCR sequencing in 60 chronic hepatitis B patients, who responded failure to long-term LAM and/or ADV therapy. RESULT: Compared with Fluorescence quantitative PCR, Direct PCR sequencing expressed a higher positive rate (43.2% vs 38.6%; 66.7% vs 54.2%, respectively) and a lower missing rate (9.5% vs 19.0%; 5.9% vs 23.5%, respectively) in the detection of drug resistance in the patients treated with LAM or combination therapy of LAM with ADV. The sensitivity of experiment using Direct PCR sequencing seemed better than Fluorescence quantitative PCR, although the difference was not significant. Further analysis on sensitivity and specificity of detection between high and low viral loads groups indicated that the consensus of two experiments in high viral load group is better than that in low viral load group (Chi-square test = 5.18, probability value = 0.023). In low viral load group, Direct PCR sequencing expressed higher sensitivity and higher specificity than Fluorescence quantitative PCR, although the difference did not approach significant. CONCLUSION: Direct PCR sequencing is better than Fluorescence quantitative PCR in the detection of drug resistance in clinic, not only with higher sensitivity and specificity, but also with comprehensive information of HBV polymerase RT region.

Efficacy and Safety of Tenofovir and Lamivudine in Combination with Efavirenz in Patients Co-infected with Human Immunodeficiency Virus and Hepatitis B Virus in China.

BACKGROUND: The prevalence of hepatitis B virus (HBV) infection is high among individuals infected with human immunodeficiency virus (HIV) in China. Both HIV and HBV can be treated with tenofovir disoproxil fumarate (TDF) and lamivudine (3TC), so we evaluated the safety and efficacy of combination antiretroviral therapy (ART) that included TDF, 3TC, and efavirenz (EFV) among ART-naive individuals who were co-infected with HIV and HBV. METHODS: One hundred HIV/HBV co-infected ARV-naive individuals were started on the regimen of TDF, 3TC, and EFV, and the levels of plasma HBV DNA, HIV RNA, and biochemical evaluation related to the function of liver and kidney were analyzed. RESULTS: Concerning efficacy, this study found that by week 48, the vast majority co-infected participants receiving this ART regimen had undetectable HBV DNA levels (71%) and/or HIV RNA levels (90%). Concerning safety, this study found that the median estimated glomerular filtration rate of participants decreased from baseline (109 ml·min-1·1.73 m-2) to week 12 (104 ml·min-1·1.73 m-2) but was almost back to baseline at week 48 (111 ml·min-1·1.73 m-2). CONCLUSION: This combination ART regimen is safe and effective for patients with HIV/HBV co-infection. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01751555; https://clinicaltrials.gov/ct2/show/NCT01751555.

Virological and immunological outcomes in HIV-1-infected Chinese patients treated with a combination of Efavirenz and Indinavir for 48 weeks.

BACKGROUND: The incidence of HIV-1-related infection diseases and the mortality of AIDS have dramatically decreased since highly active antiretroviral therapy began to be used clinically in China in 1999. And we initiated a second clinical trial using a combination of Efavirenz and Indinavir to observe the effects of the immunoreaction. METHODS: Twenty patients with laboratory-confirmed chronic HIV-1 infection were recruited. Blood samples were collected initially and during the weeks after initiation of treatment. Within 48 hours of blood sampling, peripheral blood plasma and mononuclear cells were separated using routine methods. HIV-1 viral load was measured in thawed plasma samples. Within 48 hours of peripheral blood sampling, CD4(+) and CD8(+) T cell subsets were enumerated. RESULTS: The drug regimen was efficient in reducing HIV-1 plasma viral load and increasing total CD4(+) T cell counts. The percentage of CD4(+) and CD8(+) T cell subsets expressing CD38 and HLA-DR activation markers was positively correlated with plasma viral load and tended to normalize. CONCLUSIONS: The combination of Efavirenz and Indinavir was generally well tolerated and efficient at reducing HIV-1 RNA. Furthermore, the treatment improved the immunological function.

Antiviral drug resistance increases hepatocellular carcinoma: a prospective decompensated cirrhosis cohort study.

AIM: To study the clinical outcome of antiviral therapy in hepatitis B-related decompensated cirrhotic patients. METHODS: Three hundred and twelve patients with decompensated hepatitis B cirrhosis were evaluated in a prospective cohort. With two years of follow-up, 198 patients in the group receiving antiviral therapy with nucleos(t)ide analogues and 39 patients in the control group without antiviral treatment were analysed. RESULTS: Among the antiviral treatment patients, 162 had a complete virological response (CVR), and 36 were drug-resistant (DR). The two-year cumulative incidence of hepatocellular carcinoma (HCC) in the DR patients (30.6%) was significantly higher than that in both the CVR patients (4.3%) and the control group (10.3%) (P < 0.001). Among the DR patients in particular, the incidence of HCC was 55.6% (5/9) in those who failed rescue therapy, which was extremely high. The rtA181T mutation was closely associated with rescue therapy failure (P = 0.006). The Child-Pugh scores of the CVR group were significantly decreased compared with the baseline (8.9 ± 2.3 vs 6.0 ± 1.3, P = 0.043). CONCLUSION: This study showed that antiviral drug resistance increased the risk of HCC in decompensated hepatitis B-related cirrhotic patients, especially in those who failed rescue therapy.

[Expression and purification of TAT-HBX-EGFP fusion protein and its transmembrane distribution in mouse].

OBJECTIVE: To highly express TAT-HBX-EGFP fusion protein and study its distribution in mouse liver. METHODS: TAT-HBX-EGFP recombinant vector was constructed and fusion protein was induced by IPTG and expression in BL21; fusion protein was purified by Ni-NTA argarose, then injected into the peritoneal cavity of the mice. Distribution of fusion protein was observed by immunofluorescence. RESULTS: TAT-HBX-EGFP was highly expression in E. coli; HBX could be induced into mouse liver by TAT. CONCLUSION: HBX protein could be induced into mouse liver by TAT induced peptide.

[Study on the epidemiology and distribution of human immunodeficiency virus-1 and hepatitis C virus infection among intravenous drug users and illegal blood donors in China].

OBJECTIVE: To determine the epidemiologic features and distribution of human immunodeficiency virus-1 (HIV-1) and hepatitis C virus (HCV) infection among intravenous drug users and illegal blood donors in China. METHODS: Polymerase chain reaction (PCR) amplification and DNA sequencing were used to evaluate the HIV-1 gag p17 and env C2-V3 regions, as well as the HCV 5'NCR and E1/E2 regions. RESULTS: Among 239 subjects with reported HIV-1 infection, 56.9% (136/239) were seropositive for anti-HCV. Of those, 96.3% (131/136) were co-infected with HCV through intravenous drug use and illegal blood donation. Intravenous drug users in Yunnan, Guangxi and Xinjiang provinces were infected with HIV-1 subtype C and HCV genotypes 1b, 3a, 3b and 4, whereas illegal blood donors in Henan province harbored HIV-1 subtype B' and HCV genotypes 1b and 2a. Five different HIV-1 subtypes were identified among 17 HIV-1-infected individuals from Beijing. CONCLUSIONS: Multiple HIV-1 subtypes and HCV genotypes were identified in China which were associated with several different modes of transmission. Homogeneity within the sequences of the two viruses suggested the recent, but separate, outbreaks of HIV-1 and HCV infection. The distinct distribution patterns of HIV-1 and HCV genotypes in two high-risk groups seemed to be more closely linked to the mode of transmission than to geographic proximity.

[Study on the distribution of human immunodeficiency virus-1 subtypes in different regions of China and mother-to-child transmission].

OBJECTIVE: To study the distribution of human immunodeficiency virus (HIV)-1 genotypes in major prevalent regions of China and to illustrate the relationship between HIV-1 subtypes and mother-to-child transmission in a retrospective cohort. METHODS: HIV-1 gag p17 and env C2-V4 region were amplified by nested-polymerase chain reaction (nPCR) and the sequences were obtained by sequencing gag nPCR products or clones of env gene. RESULTS: 60 HIV-1 positive individuals were subject to typing for gag p17 and 69 for env C2-V4 region. Single clade was only found in Henan (subtype B') and Xinjiang (subtype C), and subtypes C and E were demonstrated in Yunnan. These regions represented most of the HIV-1 infections in China. Multiple subtypes (A, B, C, E, etc.) were found in Beijing and Shanghai, where HIV infections were still in low level. The sequences of subtype C were less diversive in Xinjiang (p17: 0.0192 +/- 0.0078, C2-V4: 0.0455 +/- 0.0145) than in Yunnan (p17: 0.0279 +/- 0.0102, C2-V4: 0.0482 +/- 0.0171), but all of them clustered in "C" branch in phylogenetic trees. Trafficking of subtype C from Yunnan to Xinjiang was found but had already been reported by others. Compared to subtype C, subtype E was quite divergent (p17: 0.0473 +/- 0.0105, C2-V4: 0.1114 +/- 0.0112) in Yunnan, but no recombination was found in the C2-V4 region of env gene. Highe divergence of subtype B' was found in Henan and the peripheral provinces (p17: 0.0381 +/- 0.0101, C2-V4: 0.0691 +/- 0.0166), which might be attributed to the early epidemics of HIV-1 in these areas (early 1990's). In maternal-child cohort, subtypes B (7/21), C (11/21), E (1/21) and undefined types (2/21) were identified in non-transmitting HIV-1 positive mothers, while only subtype B (7/11) and C (4/11) appeared in transmitting HIV-1 positive mothers. The rate of transmission was 53.8% (7/13) in mothers infected with subtype B and 30.8% (4/13) in those infected with subtype C, but with no significant difference (P = 0.196). The imbalancing distribution of subtypes might be explained by the fact that transfusion or illegal blood would increased mother-to-child transmission on HIV-1 and most of mothers with clade B were infected by illegal blood transfusion in this cohort. In addition, most of the maternal-child pair's sequences clustered in gag or env phylogenetic trees but only a few did disperse among the unrelated patients because children were older (>/= 4 years). CONCLUSION: The characteristics of HIV-1 clade's distribution differed over most parts of China but no difference was demonstrated between subtype B and C in mother-to-child transmission on HIV-1.