ANTİ-HCV POZİTİF SERUM ÖRNEKLERİNDE VİREMİ ORANLARININ VE ANTİ-HCV DÜZEYLERİ İLE İLİŞKİSİNİN ARAŞTIRILMASI

Dünya nüfusunun yaklaşık %3'ünün Hepatit C virüsü (HCV) ile infekte olduğu tahmin edilmektedir. HCV infeksiyonunun tanı ve takibi, serolojik yöntemlerle anti-HCV antikorlarının taranması ve moleküler yöntemlerle HCV-RNA'nın tespitini içerir. HCV antikor testleri, kronik HCV infeksiyonlu hastalarda çok duyarlı ve özgül iken, aktif HCV infeksiyonu ve geçirilmiş infeksiyonu ayırmada yetersiz kalmaktadır. Moleküler yöntemler, aktif HCV replikasyonunu göstermede kullanılan altın standart yöntemler olarak düşünülmektedir. Çalışmamızda, anti-HCV'si pozitif serum örneklerinde HCV-RNA pozitiflik oranlarının ve HCV-RNA pozitifliğinin Anti-HCV düzeyleri (signal sample/cut-off =S/Co) ile ilişkisinin belirlenmesi amaçlanmıştır. Serum örneklerinde anti-HCV, ELISA (Elecsys Anti-HCV II assay, Roche) yöntemi ile incelenmiştir. Anti-HCV pozitif 297 örnekte HCV-RNA araştırılmıştır. HCV-RNA düzeyleri kantitatif gerçek zamanlı PCR (COBAS Ampliprep/ COBAS TaqMan HCV, Roche) yöntemi ile araştırılmıştır. Çalışmamızda, 297 Anti-HCV pozitif serum örneğinin 110'unda (% 37) viremi varlığını doğrulayan HCV-RNA pozitifliği belirlenmiştir. Viremik ve non-viremik serum örnekleri arasında anti-HCV düzeylerinde (S/Co) anlamlı farklılıklar bulunmuştur. Sonuç olarak, Anti-HCV'nin yüksek S/Co değerlerinin HCV-RNA varlığı ile ilişkili olduğu belirlenmiştir. Böylece, HCV-RNA testi yapılmadan önce anti-HCV S/Co değerlerinin bilinmesi, hekimin viremi varlığını önceden tahmin etmesini sağlayacak ve HCV-RNA testlerinin yüksek maliyeti azalabilecektir

Investigation of Viremia Rates and Its Correlation With Anti-HCV Levels in Anti-HCV Positive Serum Samples

It is estimated that about 3 % of the world’s population are infected with Hepatitis C virus (HCV). The diagnosis and follow-up of HCV infection involve screening for anti-HCV antibodies by serological methods and the detection of HCV-RNA by molecular techniques. HCV antibody assays are highly sensitive and specific in patients with chronic HCV infection, where as they failed to distinguish active HCV infection and past infection. Molecular methods are considered the ‘gold standard’ for detecting active HCV replication. In our study, it is aimed to determine HCV-RNA positivity in Anti-HCV positive serum samples and its correlation with anti-HCV levels (signal sample/cut-off =S/Co). Serum samples were assayed for anti-HCV by ELISA method (Elecsys Anti-HCV II assay, Roche). A total of 297 anti-HCV positive samples were tested for HCV-RNA. The level of HCV-RNA was measured by quantitative real-time PCR (COBAS Ampliprep / COBAS TaqMan HCV, Roche). In our study, we found HCV-RNA positivity, which confirms the presence of HCV viremia, in 110 (37 %) of 297 anti-HCV positive serum samples. There were significant differences in anti-HCV levels (S/Co) between viremic and non-viremic serum samples. As a result, it is determined that high S/Co values of anti-HCV related to the presence of HCV-RNA. So, knowing about the S/Co values of anti-HCV before performing HCV-RNA testing might allow the clinician to predict presence of viremia and decrease the highcost of HCV-RNA testing

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