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Hepatitis C virus (HCV) in blood donors: diagnosis by the reverse transcriptase-polymerase chain reaction method (RT-PCR)
18.5
Viral hepatitis: basic aspects
HEPATITIS C VIRUS (HCV) IN BLOOD DONORS: DIAGNOSIS BY THE REVERSE TRANSCRIPTASE-POLYMERASE CHAlN REACTION METHOD (RT-FR) N.S.L. Goncales*:C.A. Escanhola:: F.L. G-Jr F.F.Coa$ Faculdade de CYncias MBdicas - UNICAMP ‘Hemocentro I Unicamp. LaboraMrio de Sorolcgia - 13081-970 - Campinas - SP - C. Postal 6199 Worldwide, 90% of pesttransfusion NANBH is attributed to HCV. Fii percent of these patients develop chronic hepatitis, and of these. 20% progress to cirrhosis. Association of HCV with hepatccellular carcinoma has also been reported. The serologic diagnosis using Enzymatic Immunoassay (EIA) presents some difficulties during acute phase of the disease. This recurs because HCV infection is followed by a prolonged incubation period characterized by delayed seroconversion. In addition, during the chronic phase, it is necessary to usa complementary and confirmatory tests (RIBA and PCR, respectively) to evaluate the infectivity. RT-PCR method allows the detection of viral particles during acute and chronic stages of the disease. It also permilrto evaluate efficiency of the anti-viral therapy. The scope of the present study is to evaluate the efficacy of laboratorial diagnosis of HCV in blood donors screened by EIA test, using RT-PCR. 89 blood donor samples with repeatedly reactive results by EIA test For anti-HCV (2nd generation-ABBOTT Laboratories) were hystolcgicaly diagnosed as chronic hepatitis. 32 blood donor samples with positive results were also analysed - 28 presented hystological exams showing non-specific hepatic alterations and 4 presented diagnosis of normal liver. All serum samples were analysed by complementary test using lmmunoblot (RIBA II-ORTHO Laboratories) and also by RT-PCR, according to modified RAVAGGI method. This consists of a brief reverse transcription and amplification technique without previous extraction of RNA viral from the blood samples. Our findings are shown in the table below: RlSA+ SlbPSlES PCR+ with chronic hepatitis sO(69.9) without chronic hap. lS(59.4) TOTAL 99(62.0)
RISA+ PCR6(6.7) 7(21.9) 13(10.6)
RIBAI’ RIBAI’ RISAPCR+ 3(3.4) X9.4) 6(4.6)
FCR2(6.2) 2U.6)
F-CR+ -
RISAPCR_ l(3.1) l(0.6)
TOTAL 69(iw) 32(100) 121(100)
In patients with chronic hepatitis there was a co-positivity of RIBA and PCR in about 90% of the cases,and at least one negative test in the remaining 10%. In donors without chronic hepatitis there were 59.4% co-pesitiie tests. of which 31.3% presented-one negative test and 9.3% presented both ne9ative tests. RIBA and RT-PCR were in agreement and showed a very high positivity correlation in the HCV chronic hepatitis population studied.
Viral hepatitis: basic aspects
HEPATITIS C VIRUS (HCV) IN BLOOD DONORS: DIAGNOSIS BY THE REVERSE TRANSCRIPTASE-POLYMERASE CHAlN REACTION METHOD (RT-FR) N.S.L. Goncales*:C.A. Escanhola:: F.L. G-Jr F.F.Coa$ Faculdade de CYncias MBdicas - UNICAMP ‘Hemocentro I Unicamp. LaboraMrio de Sorolcgia - 13081-970 - Campinas - SP - C. Postal 6199 Worldwide, 90% of pesttransfusion NANBH is attributed to HCV. Fii percent of these patients develop chronic hepatitis, and of these. 20% progress to cirrhosis. Association of HCV with hepatccellular carcinoma has also been reported. The serologic diagnosis using Enzymatic Immunoassay (EIA) presents some difficulties during acute phase of the disease. This recurs because HCV infection is followed by a prolonged incubation period characterized by delayed seroconversion. In addition, during the chronic phase, it is necessary to usa complementary and confirmatory tests (RIBA and PCR, respectively) to evaluate the infectivity. RT-PCR method allows the detection of viral particles during acute and chronic stages of the disease. It also permilrto evaluate efficiency of the anti-viral therapy. The scope of the present study is to evaluate the efficacy of laboratorial diagnosis of HCV in blood donors screened by EIA test, using RT-PCR. 89 blood donor samples with repeatedly reactive results by EIA test For anti-HCV (2nd generation-ABBOTT Laboratories) were hystolcgicaly diagnosed as chronic hepatitis. 32 blood donor samples with positive results were also analysed - 28 presented hystological exams showing non-specific hepatic alterations and 4 presented diagnosis of normal liver. All serum samples were analysed by complementary test using lmmunoblot (RIBA II-ORTHO Laboratories) and also by RT-PCR, according to modified RAVAGGI method. This consists of a brief reverse transcription and amplification technique without previous extraction of RNA viral from the blood samples. Our findings are shown in the table below: RlSA+ SlbPSlES PCR+ with chronic hepatitis sO(69.9) without chronic hap. lS(59.4) TOTAL 99(62.0)
RISA+ PCR6(6.7) 7(21.9) 13(10.6)
RIBAI’ RIBAI’ RISAPCR+ 3(3.4) X9.4) 6(4.6)
FCR2(6.2) 2U.6)
F-CR+ -
RISAPCR_ l(3.1) l(0.6)
TOTAL 69(iw) 32(100) 121(100)
In patients with chronic hepatitis there was a co-positivity of RIBA and PCR in about 90% of the cases,and at least one negative test in the remaining 10%. In donors without chronic hepatitis there were 59.4% co-pesitiie tests. of which 31.3% presented-one negative test and 9.3% presented both ne9ative tests. RIBA and RT-PCR were in agreement and showed a very high positivity correlation in the HCV chronic hepatitis population studied.