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    Management of Chronic Hepatitis B in Pregnancy: A Consensus Report of the Study Group for Viral Hepatitis of the Turkish Society of Clinical Microbiology and Infectious Diseases
    (Doc Design Informatics Co Ltd, 2013) Aktug-Demir, Nazlim; Asan, Ali; Ayaz, Celal; Celen, Mustafa Kemal; Kose, Skran; Kuruuzum, Ziya; Ormen, Bahar
    Study Group for Viral Hepatitis of the Turkish Society of Clinical Microbiology and Infectious Diseases set up a task force to develop a consensus report focused on chronic hepatitis B in pregnancy, a complex issue for both the mother with an advanced liver disease and the unborn child who is under the risk of hepatitis B virus (HBV) transmission. Relevant literature and international guidelines were reviewed, and recommendations agreed are presented in the report. An algorithm adapted from actual publications is also proposed for management of chronic hepatitis B in the pregnant patient. Since many women of childbearing age are in the immune tolerant phase of infection, there is generally no need for therapy and no indication to start therapy during the early stages of pregnancy. Initiation of antiviral therapy in the beginning of the third trimester in highly viremic (HBV DNA > 200 000 IU/mL) pregnant women can prevent mother-to-child-transmission of HBV despite postnatal passive and active immunoprophylaxis provided. Given its potency and its high genetic barrier to resistance, tenofovir might be an appropriate option for mothers who might need to continue their treatment for active hepatitis B after delivery.
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    Molecular characterization of drug resistance in hepatitis b viruses isolated from patients with chronical infection in Turkey
    (Kowsar Publ, 2018) Asan, Ali; Sayan, Murat; Akhan, Sıla; Koruk, Süda Tekin; Aygen, Bilgehan; Sırmatel, Fatma; Eraksoy, Haluk
    Background: Hepatitis B virus (HBV) has a high mutation rate due to its unusual replication strategy leading to the production of a large number of virions with single and double mutations. The mutations, in turn, are associated with the development of drug resistance to nucleos(t)ide analogs (NUCs) in patients before and during NUCs therapy. Objectives: The current study aimed at investigating the molecular characterization of HBV in Turkish patients with chronic hepatitis B (CHB) infection. Methods: Polymerase chain reaction (PCR) amplification and direct sequencing procedures were used to analyze mutations. The detected drug resistance mutations were divided into the nucleos(t) ide analogs primary, partial, and compensatory resistance groups. The amino acid substitutions of hepatitis B surface antigen (HBsAg) were categorized into antiviral drug - associated potential vaccine-escape mutations (ADAPVEMs) and typical HBsAg amino acid substitutions, which included hepatitis B hyperimmunoglobulin (HBIg) - selected escape mutation, vaccine escape mutation, hepatitis B misdiagnosis, and immune - selected amino acid substitutions. Results: The number of patients included in the study was 528 out of which 271 (51.3%) were treatment - naive and 351 (66.3%) were hepatitis B e antigen (HBeAg) - negative. Moreover, 325 (61.6%) were males with a mean age of 38 years (range: 18 - 69). Primary, partial, and compensatory resistance to NUCs was reported in 174 (32.9%) patients. Six different ADAPVEM motifs were determined in both treatment - naive and treatment - experienced patients, namely, sF161L/rtI169X, sE164D/rtV173L, sL172L/rtA181T, sL173F/rtA181V, sS195M/rtM204V, and sS196L/rtM204I. The prevalence of ADAPVEMs and typical HBsAg escape mutations was 5.3% (n = 28) and 34.8% (n = 184), respectively. Conclusions: The analysis of drug resistance should constitute a fundamental part of the follow - up period of patients with CHB undergone treatment with NUCs. The surveillance of development of drug resistance mutations, while receiving treatment for hepatitis B is of paramount importance to monitor and control the emerging resistance.