title: Prevalence of low positive anti-HCV antibodies in blood donors: Schistosoma mansoni co-infection and possible role of autoantibodies.
abstract: Patients infected with schistosoma frequently show a high seroprevalence of anti-hepatitis C virus (anti-HCV) antibodies. The aim of this study was to find the underlying reason for this phenomenon, and to examine a possible involvement of autoantibodies. Out of 2,400 Egyptian blood donors, 192 (8%) were anti-HCV positive by ELISA. They were 133 males and 59 females with age ranging from 27 to 48 years. According to optical density ratio (ODR) of anti-HCV antibodies, 96 cases were low positive (LP) with ODR (1-2) designated as group I, and 96 were high positive (HP) with ODR (> or =2) (group II). Both groups were examined for quantitative HCV core antigen (HCVcAg), liver function (Albumin, ALT, AST) and anti-Schistosoma mansoni(anti-Sm) IgG. Group I cases were HCVcAg negative with normal liver function tests, and 44 of them were anti-Sm positive. Ninety cases (93.75%) of group II were HCVcAg positive with markedly affected liver function tests and 72 cases were anti-Sm positive. All group I cases were examined for autoimmune markers (ANA, AMA, SMA and LKM). In group I, 33 (75%) of anti-Sm positive cases were positive for one or more of the autoimmune markers examined, while none of anti-Sm negative was positive for any marker with significant difference between the two groups (P < 0.0001). Our results primarily on blood donors indicate that LP anti-HCV frequently represents false-positive reactivity with a possible role of Sm-induced autoantibodies in this phenomenon.
authors.affiliation: Department of Clinical Pathology, Faculty of Medicine, Mansoura University, Egypt.
authors.forename: Salah
authors.initials: S
authors.lastname: Agha
authors.forename: Noha
authors.initials: N
authors.lastname: El-Mashad
authors.forename: Mohamed
authors.initials: M
authors.lastname: El-Malky
authors.forename: Huda
authors.initials: H
authors.lastname: El-Shony
authors.forename: Mohamed Zaki
authors.initials: MZ
authors.lastname: El-Sherif
authors.forename: Mohamed Abo
authors.initials: MA
authors.lastname: El-Hasan
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizokami
mesh_terms: D000328:Adult; D001323:Autoantibodies / Q000502:physiology*; D001782:Blood Donors; D005260:Female; D018937:Hepatitis C Antibodies / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012555:Schistosomiasis mansoni / Q000276:immunology*
chemical_list: D001323:Autoantibodies; D018937:Hepatitis C Antibodies