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Publications (3)6.49 Total impact

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    ABSTRACT: End-stage renal disease patients (ESRD) on maintenance hemodialysis (HD) are at increased risk of acquiring hepatitis C virus (HCV) infection. An early and accurate diagnosis of HCV infection is important for the prevention of viral transmission and the management of ESRD patients on HD but conventional ELISA and PCR have often failed to reveal active HCV infection. This study evaluated the prevalence of HCV infection in ESRD patients from all HD units in central Greece using a sensitive HCV-RNA transcription mediated amplification (TMA) assay and compared its sensitivity with that of anti-HCV ELISA. Anti-HCV antibody (third generation ELISA), HCV-RNA (TMA) and HCV genotypes (HCV TMA-LiPA) were determined in 366 ESRD Greek patients. In total, 132 (36%) ESRD patients were HCV positive by ELISA or TMA; 44 by TMA alone, 16 by ELISA alone and 72 positive by both assays. More than half of the viraemic patients had genotype 3a. HCV-RNA (TMA) assay appears to increase the accuracy in the diagnosis of HCV infection in HD patients compared to the anti-HCV ELISA and could serve as an additional screening tool in these patients.
    Journal of Clinical Virology 10/2005; 34(1):81-5. · 3.29 Impact Factor
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    ABSTRACT: Hepatitis E virus (HEV) is the causative agent for enteric non-A, non-B hepatitis. Transmission is mainly via the fecal-oral route but the possibility of an additional parenteric transmission has been raised. Patients undergoing chronic hemodialysis (HD) have an increased risk of exposure to blood transmitted agents. Previous studies concerning prevalence of antibodies to HEV (anti-HEV) among HD patients gave conflicting results. The aim of the study presented here was to determine the prevalence of anti-HEV among HD patients of a well-defined semi-rural region in central Greece (Thessalia region). All patients (n=351, 234 males, mean age 60+/-14 years) who were being treated in the HD units of central Greece (n=5) during 2001 were tested for anti-HEV antibody. Two commercially available specific solid-phase enzyme-linked immunoassays were applied for anti-HEV detection. Hepatitis B virus markers, antibodies to HCV, HIV and HTLV were also screened in all patients by commercially available assays. Serum aminotransferase (AST, ALT) levels were measured by spectrophotometry. 17 anti-HEV-positive patients were found and prevalence was 4.8%, varying from 1.8 - 9.8% in the various HD units. Prevalence of HBsAg and anti-HCV was 5.7% (2.9 - 15%) and 23.6% (11.5 - 36.2%) respectively. The anti-HEV prevalence was increased compared to healthy blood donors in Greece (0.26%, p < 0.01). The highest prevalence of anti-HEV was seen at the HD unit of the General Hospital of Karditsa (9.8%). Risk factors for anti-HEV antibody were not identified: no association was found between anti-HEV positivity and age or sex, duration of HD, hepatitis B or C virus infection markers, previously elevated aminotransferase levels or history of transfusion. Our investigation of HEV infection in the cohort of HD patients in central Greece showed that the prevalence of anti-HEV was greater than in healthy blood donors. There was no association to blood borne infections (HBV, HCV). The high prevalence of anti-HEV we found in one HD unit was probably related to a local infection in the past. However, long-term prospective studies are needed in an attempt to identify whether intra-unit factors are also responsible for the increased prevalence of serologic markers of HEV infection among HD patients.
    The International journal of artificial organs 10/2004; 27(10):842-7. · 1.76 Impact Factor
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    ABSTRACT: Objective: The aim of this study was to assess the prevalence of serological and molecular markers of hepatitis (A–E) and human T-lymphotropic viruses (HTLV) in hemodialysis (HD) patients of central Greece. Methods: 370 patients (246 males, 60 ± 14 years) attending the renal units (RUs) of central Greece (n = 5) were tested for anti-HAV IgG, hepatitis B virus markers, anti-HCV, anti-HEV, and anti-HTLV-I/II with ELISA. In 131 casual samples, regardless of anti-HCV status, a sensitive, qualitative HCV-RNA assay (Versant®, Bayer) based on transcription-mediated amplification (TMA) was applied. Results: Previous HBV infection (anti-HBc) was found in 48% and current HBV infection in 5.5% (HbsAg) of the patients. Anti-HAV was detected in 94% while anti-HDV and anti-HTLV were negative. Anti-HCV prevalence was 23% varying from 11 to 36% in the different RUs. Frequency of anti-HEV (4.1%) was also highly varying (1.4–9.8%). There was no association between the infection markers and age, sex, or history of transfusion. Anti-HCV correlated with duration of HD. HCV-RNA was detected in 44/131 samples. In 15 cases results of anti-HCV and TMA were contradicting. Two anti-HCV negative samples were HCV-RNA positive (2.3%). Conclusion: In RUs of central Greece, a high prevalence of HCV infection was found, associated with the duration of HD. The high prevalence of anti-HEV found in 1 RU must be investigated further. In some of anti-HCV-negative patients viremia was detected. This result indicates that a considerable number of HCV infections are serologically occult. HCV-RNA testing, regardless of the anti-HCV status, has to be considered seriously in HD patients.
    Hemodialysis International 01/2004; 8(1):101-101. · 1.44 Impact Factor