Presence Of B19 DNA Research Articles

Parvovirus B19 DNA detection in treatment-naïve HIV anemic patients in Lagos, Nigeria: a case control study.

Parvovirus B19 (B19) has tropism for cells of the erythroid lineage, which may lead to transient inhibition of erythropoiesis. Several studies and case reports suggested that B19 infection may contribute significantly to severe chronic anemia in HIV infected persons. To detect parvovirus B19 DNA in treatment-naïve HIV patients. This was a case control retrospective study. One hundred nineteen anemic and 81 non-anemic treatment-naïve HIV infected patients participated in the study at the Lagos University Teaching Hospital, Lagos, Nigeria. Polymerase chain reaction was used to detect B19 DNA. Out of 200 patients analysed, 13(6.5%) had parvovirus B19 DNA. Eight HIV patients with anemia had B19 DNA while five non-anemic HIV patients had B19 DNA. This suggests that the presence of B19 DNA in the blood of HIV positive individuals may contribute to anemia because the majority (61.5%) who were positive for B19 DNA had anemia as compared to the non-anemic control group (38.5%). This study shows that the presence of B19 DNA in anemic HIV infected patients is not associated with chronic anaemia in HIV infection because no significant association exist.

The effects of Parvovirus B19 infection on pregnant women and fetus

Background: Human parvovirus B19 infection during pregnancy may cause fetal loss. The aim of this study was to detect the incidence of B19 infection in cases of nonimmune hydrops fetalis (NIHF), spontaneous abortion, intrauterine fetal death (IUFD) and in healthy pregnant women. Material and Methods: Serum samples of pregnant women with NIHF (9), spontaneous abortion (27), IUFD (5) and healthy pregnant women (47) were tested by nested PCR to detect B19 DNA and by ELISA test for B19 specific IgM and IgG antibodies. In other case series of the study, paraffin-embedded fetal and placental tissue samples from 33 NIHF cases and 19 spontaneous abortion cases and placental tissues from 40 normal pregnant women at term were analyzed for B19 DNA by nested PCR. Results: B19 infection was diagnosed by PCR and ELISA tests using serum samples in 4 (44%) of 9 NIHF cases and 9 (33%) of 27 spontaneous abortion cases and in 1 (20%) of 5 IUFD cases. In addition, B19 IgG prevalence was found to be 51% (24/47) in the control group. In other case series, the presence of B19 DNA in fetal and placental tissue samples was found in 14 (42.4%) of 33 NIHF cases and 6 (31.5%) of 19 spontaneous abortion cases, while in none of 40 placental tissues samples from the control group. Conclusion: Our findings show that the incidence of parvovirus B19 infection in NIHF and spontaneous abortion cases is relatively high. Nested PCR and ELISA tests should be used together for the early diagnosis of B19 infection in pregnant women.

Frequency and Genotype of Human Parvovirus B19 among Iranian Hemodialysis and Peritoneal Dialysis Patients

Objectives: The aim of this study was to evaluate the frequency and genotype of human parvovirus B19 and its relation with anemia among Iranian patients under dialysis. Methods: Fifty hemodialysis (HD) and 33 peritoneal dialysis (PD) patients were enrolled. B19 IgG and IgM antibodies were assessed by ELISA, and the presence of B19 DNA was evaluated by nested PCR. PCR products were sequenced directly and phylogenetic analysis was performed. Results: In the HD group, the prevalence of B19 antibodies was 54% for IgG and 4% for IgM. B19 DNA was detected in 10% of the cases, and 10% showed B19 IgG and viremia simultaneously. In the PD group, the prevalence of B19 IgG and IgM was 57.6 and 0% respectively, whereas B19 DNA was found in 12.1% of the group. A total of 9.1% showed B19 IgG and viremia concurrently. There was no significant difference regarding anemia and B19 infection in either group. All B19 isolates were clustered in genotype 1A. Conclusion: Our findings indicate that B19 infection plays no role in leading chronic anemia in dialysis patients. However, persistent B19 viremia and the circulation of the same strains in dialysis patients may indicate a potential risk for the contamination of dialysis equipment and nosocomial spread of B19 infection within dialysis units.

SAT0071 Dependence of rheumatoid arthritis disease aggressivity and activity on the presence of parvovirus B19 infection markers

BackgroundThe role of parvovirus B19 (B19) infection as an initiator of the classic erosive rheumatoid arthritis (RA) is being constantly debated. The main argument against etiological association of B19 with...

Prevalence of Human Parvovirus B19, Bocavirus, and PARV4 in Blood Samples from the General Population of China and Lack of a Correlation between Parvovirus and Hepatitis B Co-Infection

Few comprehensive studies have investigated viraemia caused by human parvoviruses (HPAVs) in China. A total of 1626 of blood samples were collected from non-HBV and HBV infected Chinese subjects (adults, N = 1279; children, N = 347) from south-western and south-eastern China. DNA from three HPAVs was detected in blood samples using PCR-based assays. The epidemiological profiles and association with HBV co-infection were also analysed. Of the 1626 blood samples tested, 138 (8.49%) were found to exhibit HPAV viraemia, including 3.51% with B19, 3.75% with HBoV and 2.52% with PARV4. The presence of B19 DNA in both child and adult, as well as that of PARV4 DNA in adult,from the south-western region was significantly higher than that from the south-eastern region (P = 0.006 for B19 in children; P = 0.026 for B19 in adults; and P = 0.014 for PARV4 in adult).However, the frequency of HBoV DNA in adults from the south-western region was significantly lower than that observed in adults from the south-eastern region (P = 0.001). Furthermore, HBoV was more prevalence in male (4.9%) than in female (1.4%) individuals. In addition, no significant correlation between HBV and HPAV co-infection was found using serum samples from Chinese adults. In conclusions,the molecular prevalence of three HPAVs in blood samples exhibited variation among different populations depending on area, age and gender; No association between HPAV and HBV infection in adults was found. Our data provide a basis for improving blood safety and preventing HPAV infection in China.

Quantitative Competitive-PCR Assay to Measure Human Parvovirus B19-DNA Load in Serum Samples

The B19 virus can persist in immunocompromised patients for several months and sometimes even years because of impaired immune response. Viremia in persistent and recurrent infection may range from very low to high titers and may be associated with chronic clinical manifestations, such as chronic anemia. Several recently developed techniques that quantify B19-DNA have improved laboratory diagnosis of the infection and can help guide the choice of treatment in persistent infections (i.e., intravenous immunoglobulin (IVIG) treatment vs immunosuppression reduction). Here we describe the development of a reliable internally controlled quantitative competitive (QC)- polymerase chain reaction (PCR) assay that measures B19-DNA load in serum samples by densitometric analysis of the amplification products for monitoring B19 infection in high-risk patients. A retrospective quantification of B19-DNA in the serum samples from 48 anemic transplanted patients by the QC-PCR assay we developed in our laboratory confirmed the presence of B19-DNA in 11 of 48 samples and showed a viral DNA load between 103 and 108 B19-DNA copies/mL depending on the patients' serostatus (the highest viral load was found in IgM-positive/IgG-negative patients, that is, in patients with active B19 infection at onset). The assay also confirmed B19-DNA negative patients. Our QC-PCR assay may be easily used in monitoring B19 prototype DNA load to follow persistent infections and to better understand the relation between active B19 infection and occurrence of anemia and to assess the efficacy of IVIG therapy or immunosuppression reduction in clearing the virus in high-risk patients.

Antibody response to B19 parvovirus VP1 and VP2 linear epitopes in patients with haemophilic arthritis.

Parvovirus B19 infection occurs very frequently in patients with haemophilia on account of its transmission with plasma derivatives. In order to achieve a more defined serological pattern for the study of the role of B19 infection in haemophilic arthritis, 53 serum samples from 37 patients with haemophilic arthritis were investigated for the presence of IgG immune response against B19 VP2 and VP1 linear epitopes and VP2 conformational antigen compared to the serological reactivity against B19 NS1 and to the presence of B19 DNA in the synovial membranes. An IgG immune response against VP1 and VP2 linear epitopes was detected by immunoblot assay using recombinant proteins expressed in Escherichia coli. Specific IgG against VP2 and VP1 linear epitopes were present in 84.90 and 92.45% of haemophilic arthritis patients and in 28.0 and 64.0% of the controls (P<0.001) respectively. All 53 sera of the haemophiliacs (100%) and 66.0% of the controls (P<0.001) were IgG positive and IgM negative against VP2 structural epitopes. Specific IgG against VP2 linear epitopes, which are a serological marker of active or very recent B19 infection, proved to be significantly associated with the presence of anti-NS1 antibodies and with the presence of B19 DNA in synovial tissue in patients with haemophilic arthritis. In conclusion, in these patients the presence of B19 IgG anti-VP2 linear epitopes, in absence of IgM anti-VP2 structural antigens, can be a useful serological marker to diagnose active, recent or persistent B19 infection.

Inactivation of parvovirus B19 during pasteurization of human serum albumin.

It has been shown that HSA may be contaminated with parvovirus B19 (B19) DNA. However, the presence of B19 DNA does not necessarily indicate infectious virus. HSA is pasteurized at 60 degrees C for 10 hours and it remains unclear whether this procedure inactivates B19. Studies with animal parvoviruses indicate considerable heat resistance at 60 degrees C. However, due to the lack of a suitable cell culture system, the pasteurization process has not been investigated in the past. The recently described cell clone KU812Ep6 was used to establish a system for investigation of B19 inactivation during pasteurization. Virus-infected cells were detected by immunofluorescent staining of viral capsid antigen and by RT-PCR assay of virus-specific capsid mRNA. B19 was inactivated after 10 minutes at 60 degrees C for > or = 4 log. In contrast, porcine parvovirus was widely resistant at 60 degrees C. Inactivation of B19 was independent of the analyzed albumin products (5, 20, and 25% albumin from three manufacturers) and from the specific virus source used for the inactivation experiments. Degradation of B19 DNA by deoxyribonuclease I treatment after pasteurization indicated that the virus capsid is destroyed during heat treatment. Heat resistance of B19 markedly differs from heat resistance of animal parvoviruses. While animal parvoviruses widely withstand pasteurization of albumin, B19 was rapidly inactivated. These results confirm the safety of pasteurized albumin and are in line with its good clinical safety record with respect to B19 infection. However, conclusions regarding the safety of other blood-derived medicinal products should not be derived from B19 inactivation in albumin, because different processes or different composition of product intermediates may significantly influence B19 stability during heat treatment.

Parvoviruses and blood products

Erythrovirus B19 (B19), a small isocahedral, non-enveloped virus (18–26 nm), is a ubiquitous infection agent in industrialised countries. Depending on the infected host, B19 has a wide range of disease manifestations from asymptomatic (the majority) to severe, including persistent infection. The risk of B19 transmission by blood products is enhanced by a high virus titre in the infected donor, by pooling of a large number of donations, and by the virus's resistance to effective inactivation methods such as heat and solvent-detergent treatments. B19-DNA has been detected in single donations, in manufacture plasma pools and in plasma derivatives (clotting factors, albumin, antithrombin III and immunoglobulins) produced by different processes. B19 transmission is mostly found in patients treated with clotting factors, as shown by a higher seroprevalence in treated haemophiliacs, by the presence of B19 DNA, and by active seroconversion. Chronic B19 infection can successfully be treated with polyvalent intravenous immunoglobulins. The key role of neutralising anti-B19 antibodies and of the virus titre has been demonstrated by B19 transmission after infusion of several B19-positive plasma batches treated with solvent-detergent. Two strategies can be followed to reduce the B19 risk: (1) reducing the viral load in the manufacture plasma pool by discarding B19-DNA-positive donations; (2) developing new strong virus inactivation methods. The physico-resistant properties of B19 make it a good model for new emergent viruses capable of infecting blood products.

Cytopenia and past human parvovirus P19 infectionin patients with primary Sjögren's syndrome

Objectives: To determine the clinical significance of human parvovirus B19 infection in patients with primary Sjögren's syndrome (SS) and to investigate the immunologic and hematologic features related to B19 infection. Methods: We included 80 consecutive patients with primary SS (74 women and 6 men), with a mean age of 62 years (range, 24 to 87 years) that were seen in our Unit. All patients fulfilled the European Community criteria for SS. As controls, we included 140 consecutive sera samples analyzed for B19 antibodies in our Microbiology Department and obtained from adult inpatients and outpatients of our Hospital. Serum from all patients and controls was tested for antibodies to B19 by enzyme-linked immunosorbent assay (ELISA). Additionally, the presence of B19 DNA in serum and in circulating leukocytes was investigated by nested polymerase chain reaction (PCR). Results: Serological evidence of past B19 infection (positive IgG antibodies without IgM antibodies) was present in 28 (35%) patients with primary SS. None of these patients showed evidence for B19 'viremia, and B19 virus DNA was not detected in the circulating leukocytes of IgG-B19(+) patients. Positivity for IgM antibodies to B19 was not detected in any patient. When compared with patients without evidence of past B19 infection, those with primary SS and past B19 infection showed a higher prevalence of cytopenia (57% v 15%; P < .001), and, specifically, of leukopenia (36% v 4%; P < .001), Additionally, when compared with controls positive for IgG-1319, SS patients with these antibodies had a higher prevalence of cytopenia (57% v 13%; P < .001), leukopenia (36% v 3%; P < .001) and thrombocytopenia (21% v 0%; P = .003). Conclusions: Serological evidence of past B19 infection is associated with the presence of cytopenia in our patients with primary SS. A possible relationship between B19 infection and the presence of cytopenia in primary SS may occur in some patients immunologically or genetically predisposed.

Prevalence of parvovirus B19 DNA in bone marrow of patients with haematological disorders.

Patients with haematological disorders (n = 100) were examined for prevalence of parvovirus B19 DNA in the bone marrow and serum, irrespective of B19-related symptoms. B19 DNA was studied using 2 nested PCRs and the serum samples were further analysed with B19-specific IgG, IgM and avidity as well as seroreactivity against linear and conformational epitopes of the B19 VP2 antigen. The latter assays specify whether the IgG antibody response represents acute or past B19 infection. B19 DNA was detected in 4 of the 100 bone marrow samples, whereas all the serum samples were B19 DNA negative. None of the 4 B19 DNA positive patients had symptoms typical of B19 infection and serology showed past infection. Furthermore, 2 were still B19 DNA positive in bone marrow more than 1 y after the first sample indicating virus persistence. The seroprevalence for B19 IgG was 59% and 2 patients were B19 IgM positive. Thus, presence of B19 DNA in bone marrow from patients with haematological disorders is not a general finding in seropositive patients. B19 DNA can persist in bone marrow, but in our material this finding showed no clear correlation with symptomatic B19 infection.

B19 parvovirus induced fetal hydrops: rapid and simple diagnosis by detection of B19 antigens in amniotic fluids

In our study we describe the direct detection of parvovirus B19 capsid antigens in amniotic fluid samples for the rapid and simple prenatal diagnosis of B19 induced fetal hydrops. The assay was performed on amniotic fluid specimens from fetal hydrops dotted on nylon membranes. The two capsid antigens, VP1 and VP2, which represent four per cent and 96 per cent of the capsid, respectively, were detected using a pool of monoclonal antibodies directed against these two proteins and the complex was visualized by immunoperoxidase staining. The assay could be performed in about four hours and positive results were revealed at the end of the reaction as dark blue spots on the nylon membrane. We analysed 26 amniotic fluid samples from 26 selected cases of non-immune hydrops for the presence of B19 antigens. Out of these 26 samples, 13 had previously proved positive for B19 DNA, detected by dot blot hybridization and/or in situ hybridization and/or nested PCR, and 13 had proved negative. The results obtained with our assay were compared with results obtained for the presence of B19 DNA and a close agreement was found. The method is simple and rapid to perform, does not require costly instruments, and all the reagents used in the assay are commercially available. The assay described can thus be useful for a prompt counselling and management of B19 fetal infection.

Parvovirus B19 and Chronic Fatigue Syndrome

AbstractObjective. To investigate the skeletal muscle of patients with chronic fatigue syndrome (CFS) for parvovirus B19.Methods.DNA was extracted from skeletal muscle biopsies from six patients with CFS diagnosed according to the criteria of the Centers for Disease Control and Prevention and six control cases.Extracted DNA was checked for purity by agarose gel electrophore-sis and examined for the presence of B19 DNA by a nested polymer-ase chain reaction (PCR) method.Results.One of the six biopsies from the CFS group and one of the six from the control group were positive for B19 DNA (Two-tailed P value = 1). Nucleotide sequencing of the PCR product from the CFS patient revealed one silent mutation from A -> G at nucleotide 1530 when compared with the published sequence. Nucleotide sequencing of the PCR product from the control patient with mild arthralgia revealed 10 mutations when compared with the published sequence, all silent except the one at nt 1466 (G -> C), which resulted in an amino acid chang...

Parvovirus B19 clearance from peripheral blood after acute infection.

The clearance of B19 parvovirus from peripheral blood was followed after acute infection to determine how long the virus is present in blood, even at low titer. The presence of B19 DNA in serum was investigated with dot blot hybridization during an epidemic. Fourteen patients positive for B19 DNA were followed for up to 1 year for its presence in samples taken monthly, using both dot blot hybridization and nested polymerase chain reaction (PCR). All patients examined showed medium to high viremic titers (detectable with hybridization assay) only at the beginning of observation; later the virus titer decreased and was detectable only by nested PCR. Of the 14 patients followed, 13 were positive for B19 DNA by nested PCR for 2-6 months; 1 patient showed a persistent infection associated with chronic arthritis and was positive for B19 DNA for 1 year without clearance of the virus.

Persistent B19 parvovirus infections in haemophilic HIV-1 infected patients.

B19 infection can be acquired by transmission with blood factors in patients with congenital bleeding disorders, requiring clotting factor concentrates. In immunodeficient patients, the failure of immunity to clear B19 virus may produce persistent infections. The presence of B19 DNA in blood samples from seven haemophilic patients with concomitant HIV-1 infection was studied over a period of three-to-four years. Dot blot hybridization assays with DNA and RNA probes were used to detect medium high viremias, and polymerase chain reaction (PCR) to detect very low viremic titres. Three patients were negative for B19 DNA in all the blood samples, while four patients were persistently positive for B19 DNA. Viral persistence, which in one patient was detected throughout the study period (40 months), occurred at low titre in all four positive patients with some recurrent increases in viral titre. In the four patients persistently positive for B19 DNA, acute or chronic clinical symptoms and signs that could be associated with B19 were not noted when virus was present at low titre (B19 DNA detectable only by PCR). When patients had a higher viral titre (B19 DNA detectable by dot blot hybridization) acute manifestations (aplastic crisis, Fifth disease, fevers, pneumonitis) were found.

Albumin batches and B19 parvovirus DNA

B19 parvovirus (B19) may be transmitted iatrogenically by blood, and its prevalence in blood donations is estimated at 1 in 3,300 to 1 in 50,000. As a large number of blood donations make up the plasma pools used to produce plasma derivatives, even a virus as rare as B19 in a population of blood donors may result in the frequent contamination of plasma batches. The percentage of albumin batches containing B19 DNA has never been determined. The presence of B19 DNA was investigated by a polymerase chain reaction assay (with a primer pair in the VP1 region) in a total of 12 and 17 batches of 4- and 20-percent albumin, respectively, from two different manufacturers. No B19 DNA was detected in the batches tested. The current fractionation process used to obtain these albumin preparations is seen to allow the efficient degradation and/or elimination of B19.

B19 parvovirus DNA in solvent/detergent-treated anti-haemophilia concentrates

A transfusional B19 parvovirus infection may have severe consequences in immunocompromised hosts. The presence of B19 DNA was investigated with a polymerase chain reaction (PCR) assay in 30 batches of solvent/detergent-treated clotting factor concentrates (12 batches of factor VIII, 16 batches of factor IX, 1 batch of factor VII, and 1 batch of PPSB). B19 DNA was detected in 6 (20%) batches, including 3 factor VIII and 3 factor IX concentrates. Because of the frequency of B19 DNA in batches of clotting factors, measures to prevent transfusional risk of B19 infection via these blood products are justified, especially in recipients immunocompromised by HIV infection.

Parvovirus B19 infection in human immunodeficiency virus type 1-infected persons failing or intolerant to zidovudine therapy.

To determine the incidence of B19 infection in patients with AIDS who were being treated with dideoxyinosine, serial sera (n = 28) taken over a 2-year period from 14 individuals were analyzed with respect to anti-B19 serology and the presence of B19 DNA. All 14 individuals were anti-B19 IgM negative. Nine of 14 had B19 viremia by Southern analysis of polymerase chain reaction product. Five of 9 with B19 viremia had > or = 1 anti-B19 IgG-positive sample; none of 5 without viremia had anti-B19 IgG. Four of 9 viremic individuals had serially positive samples. All 4 had severe anemia (hemoglobin < 8.5 g/dL) while taking zidovudine. A fifth individual whose severe anemia resolved after zidovudine was discontinued did not have B19 viremia. Therefore, a significant proportion of this group of patients with AIDS who developed severe anemia while receiving zidovudine had persistent B19 infection. These results suggest that B19 infection should be considered in anemic patients with AIDS.

Fetal pathology in human parvovirus B19 infection

In a current Netherlands study on the effects on mother and child of infection with the human parvovirus B19 during pregnancy, 10 pregnancies have been reported. Three of them ended before term: two in fetal death and one by elective abortion. In two of these fetuses B19 infection in cells other than those of the erythroid series was demonstrated, and in the one terminated, ocular malformation and extensive inflammatory reactions in all fetal and placental tissues were found. The presence of B19 DNA was demonstrated by dot hybridization in placental and fetal tissues. In the third no gross fetal abnormalities were found, although B19 DNA was detected in several fetal tissues by in-situ hybridization. Of the remaining seven pregnancies, six ended at term in the birth of apparently healthy babies. The other child was born near term with a low birthweight and multiple congenital malformations, but with no proof of intrauterine B19 infection. It is concluded that B19 infection in pregnancy can interfere with organ development and may lead to intrauterine fetal death.