Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The development of new technologies leads to the discovery of new viruses. For each of these new infectious agents relevance to transfusion needs to be assessed. The questions to be answered are transmissibility by transfusion, pathogenicity, prevalence in blood donors, persistence and the availability of screening assays. Since 1995, three new viruses have been identified and extensively studied. GB virus-C/hepatitis G virus (GBV-C/HGV), a relatively rare virus with some homology with and epidemiological features of HCV, was thought to be related to post-transfusion hepatitis but was proven to be unrelated to hepatitis and is still in search of a disease. Human herpes virus-8 (HHV-8) is a major factor in the pathogenesis of Kaposi's sarcoma and other tumours related to immunodeficiency. HHV-8 transmission by organ transplantation, but not by transfusion, has been demonstrated. The TT virus (TTV) is a ubiquitous virus infecting a very high proportion of humans in infancy. No clinical symptoms or pathogenicity is attached to TTV. To date, none of the emerging viruses have been proven relevant to transfusion.
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PMID:Emerging viral infections relevant to transfusion medicine. 1112 5

GB Virus C and Hepatitis G Virus (GBV-C/HGV) are positive, single-stranded flaviviruses. GBV-C and HGV are independent isolates of the same virus. Transmission via the blood-borne route is the commonest mode, although vertical and sexual transmission is well documented. GBV-C/HGV is distributed globally; its prevalence in the general population is 10 fold higher in African countries than in non-African countries. High prevalences of GBV-C/HGV have been found in subjects with frequent parenteral exposure and in groups at high risk of exposure to blood and blood products. The clinical significance of human infection with GBV-C/HGV is currently unclear. The virus can establish both acute and chronic infection and appears to be sensitive to interferon. Only some 12-15% of chronic Non-A, B, C hepatitis cases are infected with GBV-C/HGV. A direct association with liver pathology is still lacking and it is not yet clear as to whether GBV-C/HGV is indeed a hepatotropic virus. Current evidence suggests that the spectrum of association of GBV-C/HGV infection with extrahepatic diseases ranges from haematalogical diseases, aplastic anaemia, human immunodeficiency virus (HIV)-positive idiopathic thrombocytopenia and thalassemia, through to common variable immune deficiency and cryoglobunemia.
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PMID:GB virus C/hepatitis G virus (GBV-C/HGV): still looking for a disease. 1116 78

This lecture includes three sections. Firstly, the concepts of genotype, subtype and quasi-specie are described. The appearance of virus is correlated with the evolution of the medical picture, and their resistance to antiviral agents. Secondly, the most modern genetical and molecular biology techniques, including DNA sequencing are studied. Thirdly, some examples of the investigation lines carried out at the Microbiology Department of the Granada Medicine School are explained, especially regarding to papillomavirus, hepatitis C virus, hepatitis G virus, virus associated to transfusions (TTV) and human immunodeficiency. The great transcendence that the genetical variability has to establish pathogeny and therapy control is emphasized.
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PMID:[Viral genotypes in different infective processes]. 1164 68

In multiply coinfected human immunodeficiency virus (HIV)-positive patients, we investigated the effects of high-activity antiretroviral therapy (HAART) using HIV protease inhibitors on three other viruses: hepatitis C virus (HCV), hepatitis G virus (HGV), and TT virus (TTV). Viral concentrations were measured serially by polymerase chain reaction methods in five patients with quadruple infection (HIV, HCV, HGV, and TTV) and in two patients with triple infection (HIV, HCV, and HGV) before and during HAART. In addition, CD4+ cell counts and serum alanine aminotransferase (ALT) levels were measured serially. Generally we observed no difference in serum HCV RNA, HGV RNA, or TTV DNA concentrations between samples obtained before and after initiation of HAART, whereas HIV RNA concentration decreased and CD4 counts increased in most patients. However, two patients had markedly decreased concentrations of HCV RNA and HGV RNA, respectively, more than 12 months after beginning HAART. Normalization of serum ALT levels was observed in a patient with decline of HCV RNA concentrations. No interactions were observed among these four viruses. HAART had no apparent direct effects on HCV, HGV, or TTV. Further studies will be required to elucidate whether the restoration of immune status through suppression of HIV replication by HAART may affect HCV or HGV RNA concentrations.
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PMID:Effects of HAART on hepatitis C, hepatitis G, and TT virus in multiply coinfected HIV-positive patients with haemophilia. 1185 56

Flaviviridae-hepatitis C virus (HCV) and GB virus C/hepatitis G virus (GBV-C/HGV)--and human immunodeficiency virus (HIV) frequently show similar modes of transmission. HCV and GBV-C/HGV infection was assessed in 134 consecutive patients with evidence of HIV infection, living in Campania, Italy. Data obtained from this cohort were compared with those obtained from 252 age- and sex-matched HCV infected patients without evidence of HIV infection (HCV control group). Following enzymatic immunoassays, samples were tested for the presence of HCV-RNA by RT-PCR. The HCV-RNA positive sera were genotyped by LiPA procedure. The prevalence of HCV infection in HIV patients was 19.40% and the largest group of HIV-HCV co-infected patients (84.62%) was represented by intravenous drug users (IVDU). The distribution of HCV genotypes in HIV-HCV patients was different, compared to that observed in HCV control group. HCV genotypes la (50%) and 3a (23.08%) were more frequently detected in HIV HCV patients, compared to HCV control group (5.16 and 5.56% for la and 3a, respectively). Conversely, HCV genotypes lb (55.70%) and 2a/2c (30.26%) were more represented in HCV control group, compared to HIV-HCV patients (15.38 and 0% for lb and 2a/2c, respectively). GBV-C/HGV seroprevalence was 41.04% in HIV patients and 6.54% in healthy control individuals. Differently from HCV, GBV-C/HGV infection did not correlate to a preferential risk behaviour in the HIV cohort. Comparative analysis of HCV and GBV-C/HGV infection indicates that the use of injecting drugs might play a key role in the epidemiology of HCV and, in particular, of la and 3a HCV genotypes, in HIV patients.
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PMID:HCV and GBV-c/HGV infection in HIV positive patients in southern Italy. 1208 Oct 97

The development of new technologies leads to the discovery of new viruses. For each of these new infectious agents, relevance to transfusion, including transmissibility by transfusion, pathogenicity, prevalence in blood donors, persistence and the availability of screening assays needs to be assessed. Since 1995, one virus and a new family of viruses have been identified. GB virus-C/hepatitis G virus (GBV-C/HGV), a flavi virus with some homology with and epidemiological features of HCV, is not related to post-transfusion hepatitis but seems to positively interfere with human immunodeficiency virus replication. Human circoviruses include TT virus (TTV) and SEN-V. Both are highly variable, constituting a large family of distantly related viruses. They appear ubiquitous, infecting humans very early in life and are largely persistent. No clinical symptoms or pathogenicity is associated with TTV, but SEN-V might be associated with some non-A-E post-transfusion hepatitis. Parvovirus B19 has been known for many years, but its transmission to recipients of plasma derivatives despite viral inactivation raised the issue of screening plasma pools by nucleic acid testing. Most fractionators quantify B19 DNA in plasma pools to ensure a viral load of <10(4) IU mL-1.
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PMID:Nucleic acid testing for emerging viral infections. 1222 Feb 57

Antibodies to hepatitis G virus(HGV) and human immunodeficiency virus(HIV) by EIA were investigated in 831 healthy youths from 6 provinces. The results showed that the anti-HGV IgG positive rate was 2.53% (21/831). In 21 anti-HGV IgG positive sera, HGV RNA was detected in 8 sera by reverse transcription polymerase chain reaction(RT-PCR). The anti-HIV was negative in 827 sera. The data suggest that HGV infection actually exist in healthy youths.
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PMID:[Investigation of hepatitis G virus and human immunodeficiency virus infections in 831 healthy youths]. 1252 51

City-dwelling children from Kenya who were infected with human immunodeficiency virus type 1 (HIV-1) were tested for coinfection with cytomegalovirus (CMV), human T cell lymphotropic viruses 1 and 2, Kaposi sarcoma-associated herpesvirus (KSHV), or hepatitis B, C, and G viruses. All children were found to be coinfected with CMV, whereas 5% had hepatitis G virus coinfection and 15% had KSHV coinfection. A protective role for hepatitis G virus cannot be excluded but likely affects only a minority of HIV-1-infected African children.
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PMID:Viral coinfections among African children infected with human immunodeficiency virus type 1. 1265 94

Hepatitis C virus (HCV) can be classified into six major genotypes, the prevalences of which differ around the world. In Japan, the main genotypes are HCV 1 and HCV 2; others are found only rarely. Little is known about the prevalence in Japan of HCV genotype 4 which, is found frequently in North and Central Africa and the Middle East. Thus, we conducted a study to clarify distribution of HCV genotype 4 and the clinical demographics of patients with HCV genotype 4 in Japan. We examined HCV genotypes in 899 Japanese individuals with HCV viremia living in Aichi Prefecture, including 63 hemophiliacs. Four patients (0.4%) were infected with HCV genotype 4. All four of these patients were male hemophiliacs who had received clotting factors from foreign countries. Three patients were co-infected with human immunodeficiency virus (HIV); none were co-infected with GB virus-C/hepatitis G virus. Phylogenetic analysis of the El region indicated that all four patients were infected with subtype 4a. This subtype is related genetically to a subtype previously reported in Japanese and Italian hemophiliacs. HCV genotype 4 is indeed rare in Japan and may be detected only among hemophiliacs who have received inactivated clotting factor concentrates from foreign countries.
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PMID:Prevalence and characterization of hepatitis C virus genotype 4 in Japanese hepatitis C carriers. 1269 51

The prevalence of human immunodeficiency virus (HIV) infection and hepatitis B, C, and G virus infections was determined in a selected group of 40 intravenous drug addicts on methadone maintenance treatment. No drug addict was infected with HIV. Seven drug addicts (17.5%) had serologic markers of hepatitis B infection but only one among them (2.5%) exhibited signs of active infection. 16 drug addicts (40%) had serologic markers of hepatitis C infection and 13 (32.5%) of them had an active infection with positive viral tests. 22 addicts (55%) had signs of hepatitis G infection, 9 (22.5%) of them had signs of active infection and 13 (32.5%) had signs of past infection. Addicts infected with the hepatitis B and C viruses were older and had also been taking drugs longer than those who were not infected with these two viruses. The proportion of those susceptible to infection with hepatitis B (70%) is high, reflecting a low prevalence of this disease and at the same time revealing the failure of preventive measures and the unacceptably low vaccination rate.
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PMID:Prevalence of HIV, hepatitis B, C and G virus infections among injecting drug users on methadone maintenance treatment in Maribor. 1550 2


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