Detection of Human Parvovirus B19 Nonstrutural Protein DNA by Nested-Polymerase Chain Reaction in Gravida Serum and Pregnant Tissues

A new nested-polymerase chain reaction （nested-PCR） assay was developed to detect human parvovirus B19 DNA corresponding to the nonstructural protein in clinical specimens in a routine diagnostic laboratory. The sensitivity of this highly specific assay was up to 0. 005 fg of B19 DNA. Parvovirus B19 was identified in sera of 20 pregnant women with abnormal pregnant outcome. Among these 20 cases, intrauterine parvovirus infection did exist in 7 pregnant women because parvovirus B19 DNA was detected in the pregnant tissues of them such as placenta tissues, chorionic villi, amniotic fluid, fetal spleen, liver and abdominal fluids.

RELATIONSHIP BETWEEN HUMAN PARVOVIRUS B19 INFECTION AND APLASTIC ANEMIA

Objective. To explore the relationship between human parvovirus B19 (HPV B19) infection and aplastic anemia (AA) and to investigate the role of HPV B19 in the occurrence of AA. Methods. The presence of HPV B19 DNA was detected in the peripheral blood samples of 60 patients with AA (children 38 and adults 22) by nested polymerase chain reaction (PCR) assay, and 30 healthy persons were selected as control. Results. Sixteen (26.7％ ) of 60 AA cases were HPV B19 DNA positive, while all the samples in the control group were negative for HPV B19 (P = 0.000914). Among the case group, the positive rates of HPV B19 DNA were 21.4％ (6 / 28), 30.0％ (3 / 10), 20.0％ (1 / 5) and 35.3％ (6 / 17) in children acute AA (AAA), children chronic AA (CAA), adults AAA and adults CAA patients respectively, which were significantly higher than that in the control group. Furthermore, there was no remarkable difference between children AA and adults AA in the 16 HPV B19 DNA positive patients; neither was there between AAA and CAA. Conclusions. HPV B19 infection is not only correlated with the occurrence of children AAA and CAA, but also with adults AAA and CAA, and might be an important viral cause for AA in humans.

Investigation on the Maternal-Infantile Infection with Human Parvovirus B19

To investigate the maternal-infantile infection with human parvovirus B19, the IgG and IgM antibodies against human parvovirus and the B19-DNA in serum and peripheral blood mononuclear cells (PBMC) of pregnant women as well as the serum IgM antibody against B19 and the B19-DNA in serum and cord blood nucleated cells (CBNC) of newborns were determined by ELISA and nested PCR respectively. It was found that the positive rate of the IgG antibody against human parvovirus B19 in sera of 92 pregnant women was 38.04% (35/92), and that of the IgM antibody in 720 pregnant women was 9.03% (65/720). However, the IgM antibody against human parvovirus B19 was negative in the cord blood sera of 95 newborns. As to the human parvovirus B19 DNA, none of 720 pregnant women and 95 newborns was proved to be positive in their sera. Nevertheless, the positive rate of the parvovirus B19 DNA in PBMC was 3.06% (3/98) in 98 pregnant women and 1.12% (1/89) in CBNC of 89 newborns. It is concluded that the history of infection with human parvovirus B19 exists in certain pregnant women with a small percentage of pregnant women infected with recent or acute infections of B19 virus. The detection rates of the B19 viral DNA in PBMC of pregnant women and CBNC of newborns were higher than those in sera, indicating that the risk for vertical transmission is very low.

The effects of co-infection with human parvovirus B19 and Plasmodium falciparum on type and degree of anaemia in Ghanaian children

Objective:To determin the extent to which parvovirus B19(B19V)and co-infection of B19V and malaria contribute to risk of anaemia in children.Methods:B19V DNA and malaria parasites were screened for 234 children at the PMI,Children's Hospital in Accra.The role of B19V and coinfection with B19V and malaria in anaemia was evaluated by analysing full blood cell counts,malaria and B19V DNA results from these children.Results:The prevalence of B19V,malaria and co-infection with B19V and malaria was 4.7%,41.9%and 2.6%,respectively.Malaria posed a greater risk in the development of mild anaemia compared to severe anaemia(OR=5.28 vrs3.15)whereas B19V posed a higher risk in the development of severe anaemia compared to mild anaemia(OR=4.07 vrs 1.00)from a non-anaemic child.Persons with co-infection with B19V and malaria had 2.23 times the risk(95%CI=0.40-12.54)of developing severe anaemia should they already have a mild anaemia.The degree of anaemia was about three times affected by coinfection(Pillai's trace=0.551,P=0.001)as was affected by malaria alone(Pillai's trace=0.185,P=0.001).B19V alone did not significantly affect the development of anaemia in a non-anaemic child.Microcytic anaemia was associated with B19V and co-infection with B19V and malaria more than normocytic normochromic anaemia.Conclusions:B19V was associated with malaria in cases of severe anaemia.The association posed a significant risk for exacerbation of anaemia in mild anaemic children.B19V and co-infection with B19V and malaria may be associated with microcytic anaemia rather than normocytic normochromic anaemia as seen in cases of B19V infection among persons with red cell abnormalities.

Molecular phenotypes of human parvovirus B19 in patients with myocarditis

AIM:To investigate molecular phenotypes of myocardial B19V-infection to determine the role of B19V in myocarditis and dilated cardiomyopathy(DCM).METHODS:Endomyocardial biopsies(EMBs) from 498 B19V-positive patients with myocarditis and DCMwere analyzed using molecular methods and functional experiments.EMBs were obtained from the University Hospitals of Greifswald and Tuebingen and additionally from 36 German cardiology centers.Control tissues were obtained at autopsy from 34 victims of accidents,crime or suicide.Identification of mononuclear cell infiltrates in EMBs was performed using immunohistological staining.Anti-B19V-IgM and anti-B19V-IgG were analyzed by enzyme-linked immunosorbent assay(ELISA).B19V viral loads were determined using in-house quantitative real-time polymerase chain reaction(PCR).For B19V-genotyping a new B19V-genotype-specific restriction fragment length polymorphism(RFLP)-PCR was established.B19V-genotyping was verified by direct DNAsequencing and sequences were aligned using BLAST and BioEdit software.B19V P6-promoter and HHV6-U94-transactivator constructs were generated for cell culture experiments.Transfection experiments were conducted using human endothelial cells 1.Luciferase reporter assays were performed to determine B19Vreplication activity.Statistical analysis and graphical representation were calculated using SPSS and Prism5 software.RESULTS:The prevalence of B19V was significantly more likely to be associated with inflammatory cardiomyopathy(iCMP) compared to uninflamed DCM(59.6% vs 35.3%)(P < 0.0001).The detection of B19V-mRNA replication intermediates proved that replication of B19V was present.RFLP-PCR assays showed that B19V-genotype 1(57.4%) and B19V-genotype 2(36.7%) were the most prevalent viral genotypes.B19V-genotype 2 was observed more frequently in EMBs with iCMP(65.0%) compared to DCM(35%)(P = 0.049).Although there was no significant difference in gender-specific B19V-loads,women were more frequently infected with B19V-genotype 2(44.6%) than men(36.0%)(P = 0.0448).Coinfection with B19V and other cardiotropic viruses was found in 19.2% of tissuesamples and was associated with higher B19V viral load compared to B19V-monoinfected tissue(P = 0.0012).The most frequent coinfecting virus was human herpes virus 6(HHV6,16.5%).B19V-coinfection with HHV6 showed higher B19V-loads compared to B19V-monoinfected EMBs(P = 0.0033),suggesting that HHV6 had transactivated B19V.In vitro experiments confirmed a 2.4-fold increased B19V P6-promoter activity by the HHV6 U94-transactivator.CONCLUSION:The finding of significantly increased B19V loads in patients with histologically proven cardiac inflammation suggests a crucial role of B19V-genotypes and reactivation of B19V-infection by HHV6-coinfection in B19V-associated iCMP.Our findings suggest that B19V-infection of the human heart can be a causative event for the development of an endothelial cell-mediated inflammatory disease and that this is related to both viral load and genotype.

Acute encephalitis and encephalopathy associated with human parvovirus B19 infection in children

Reports of neurologic manifestations of human parvovirus B19(B19) infection have been on the rise. Acute encephalitis and encephalopathy is the most common, accounting for 38.8% of total B19-associated neurological manifestations. To date, 34 children with B19encephalitis and encephalopathy have been reported, which includes 21 encephalitis and 13 encephalopathy cases. Ten(29%) were immunocompromised and 17(39%) had underlying diseases. Fever at the onset of disease and rash presented in 44.1% and 20.6% of patients, respectively. Neurological manifestations include alteration of consciousness occurred in all patients, seizures in 15(44.1%) patients, and focal neurologic signs in 12(35.3%) patients. Anemia and pleocytosis in cerebrospinal fluid(CSF) occurred in 56.3% and 48.1% of patients, respectively. Serum Anti-B19 Ig M(82.6%) and CSF B19 DNA(90%) were positive in the majority of cases. Some patients were treated with intravenous immunoglobulins and/or steroids, although an accurate evaluation of the efficacy of these treatment modalities cannot be determined. Nineteen(57.6%) patients recovered completely, 11(33.3%) patients had some neurological sequelae and 3(8.8%) patients died. Although the precise pathogenesis underlying the development of B19 encephalitis and encephalopathy is unclear, direct B19 infection or NS1 protein of B19 toxicity in the brain, and immune-mediated brain injuries have been proposed.

The Impact of Human Parvovirus B19 Co-Infection on Liver Function of HCV Infected Patients

Background: Human Parvovirus B19 is most known for causing disease in the pediatric population but can also affect adults. Human co-infection with Parvovirus B19 could deteriorate the prognosis of patient with chronic ill-ness. Objectives: This paper attempts to determine the prevalence of Parvovirus B19 in HCV infected patients and to evaluate the impact of Parvovirus B19 on liver enzymes activity of Hepatitis C patients. Study Design: The study population includes 74 chronic HCV (patient group) and 49 cases without viral hepatitis (control group). Nucleic acid of Parvovirus B19 was detected in Serum samples by nested polymerase chain reaction (nested-PCR) method. Results: Parvovirus B19-DNA infection was detected in 28.0% of chronic HCV patients. Parvovirus B19-HCV co-infection caused increasing in Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST) activity than in B19-negative HCV patients. Conclusion: We conclude that Parvovirus B19 acted synergistically with HCV by increasing the levels alanine ami-notransferase (ALT) and Aspartate aminotransferase (AST).

Human parvovirus B19-associated early postoperative acquired pure red cell aplasia in simultaneous pancreas-kidney transplantation:A case report

BACKGROUND Acquired pure red cell aplasia(aPRCA)related to human parvovirus B19(HPV B19)is rarely reported in simultaneous pancreas-kidney transplantation(SPKT)recipients;there has yet to be a case report of early postoperative infection.In this current study,we report the case of a Chinese patient who experienced the disease in the early postoperative period.CASE SUMMARY A 63-year-old man,with type 2 diabetes and end-stage renal disease,received a brain dead donor-derived SPKT.Immunosuppression treatment consisted of tacrolimus,prednisone,enteric-coated mycophenolate sodium(EC-MPS),and thymoglobulin combined with methylprednisolone as induction.The hemoglobin(Hb)level declined due to melena at postoperative day(POD)3,erythropoietinresistant anemia persisted,and reticulocytopenia was diagnosed at POD 20.The bone marrow aspirate showed decreased erythropoiesis and the presence of giant pronormoblasts at POD 43.Metagenomic next-generation sequencing(mNGS)of a blood sample identified HPV B19 infection at POD 66.EC-MPS was withdrawn;three cycles of intravenous immunoglobulin(IVIG)infusion therapy were administered;and tacrolimus was switched to cyclosporine.The HPV B19-associated aPRCA resolved completely and did not relapse within the 1-year follow-up period.The diminution in mNGS reads was correlated with Hb and reticulocyte count improvements.CONCLUSION HPV B19-associated aPRCA can occur at an early period after SPKT.An effective therapy regimen includes IVIG infusion and adjustment of the immunosuppressive regimen.Moreover,mNGS can be used for the diagnosis and to reflect disease progression.

Human parvovirus B19-associated hematopathy in HIV disease:need for clinicopathological revisit

Persons living with HIV infection occasionally suffer from anemia due to varying causes.These include the use of zidovudine,malnutrition especially vitamin B12and iron deficiency,opportunistic infections by Mycobacterium tuberculosis,Pneumocystis jiroveci,and direct hematological effects of HIV infection itself within the marrow microenvironment.Persistent Parvovirus B19（B19V）infection is a clinically important and treatable etiology of anemia in HIV-infected persons.

Pure Red Cell Aplasia Caused by Parvovirus B19 in Patients with Human Immunodeficiency Virus Infection: A Series of Four Cases

Parvovirus B19(B19V)infection can cause pure red cell aplasia(PRCA)in patients with human immunodeficiency virus(HIV)infection.Intravenous immunoglobulin(IVIG)is a preferred treatment option.From July 2019 to March 2022,four patients with HIV infection were admitted to Guangzhou Eighth People’s Hospital with dizziness and fatigue and were diagnosed with PRCA.Blood investigations revealed severe anemia and the B19V genome.Therefore,the four patients were diagnosed with B19V-induced PRCA.All four patients received red blood cell transfusion in the setting of antiretroviral therapy,and two of the four patients received intravenous immunoglobulin(IVIG).After 3-7 months of treatment,all four patients recovered,although two did not receive IVIG.This suggests that IVIG is not always necessary for the treatment of PRCA in patients with HIV infection and that effective antiretroviral therapy and immunological reconstitution play an important role in the eradication of parvovirus.

Pure red cell aplasia due to parvovirus B19 infection after liver transplantation:A case report and review of the literature

Pure red cell aplasia （PRCA） due to parvovirus B19 （PVB19） infectiori after solid organ transplantation has been rarely reported and most of the cases were renal transplant recipients, Few have been described after liver transplantation. Moreover, little information on the management of this easily recurring disease is available at present. We describe the first case of a Chinese liver transplant recipient with PVB19-induced PRCA during immunosuppressive therapy. The patient suffered from progressive anemia with the lowest hemoglobin level of 21 g/L. Bone marrow biopsy showed selectively inhibited erythropoiesis with giant pronormoblasts. Detection of PVB19-DNA in serum with quantitative polymerase chain reaction （PCR） revealed a high level of viral load. After 2 courses of intravenous immunoglobulin （IVIG） therapy, bone marrow erythropoiesis recovered with his hemoglobin level increased to 123 g/L. He had a lowlevel PVB19 load for a 5-too follow-up period without recurrence of PRCA, and finally the virus was cleared. Our case indicates that clearance of PVB19 by IVIG in transplant recipients might be delayed after recovery of anemia.

Parvovirus B19 induced hepatic failure in an adult requiring liver transplantation

Parvovirus B19 induced acute hepatitis and hepatic failure have been previously reported, mainly in children. Very few cases of parvovirus induced hepatic failure have been reported in adults and fewer still have required liver transplantation. We report the case of a 55-year-old immunocompetent woman who developed fulminant hepatic failure after acute infection with Parvovirus B19 who subsequently underwent orthotopic liver transplantation. This is believed to be the first reported case in the literature in which an adult patient with fulminant hepatic failure associated with acute parvovirus B19 infection and without hematologic abnormalities has been identified prior to undergoing liver transplantation. This case suggests that Parvovirus B19 induced liver disease can affect adults, can occur in the absence of hematologic abnormalities and can be severe enough to require liver transplantation.

Seroprevalence of parvovirus B19 antibodies and evidence of viremia among Nigerian patients with sickle cell anemia

Clinical, biochemical and molecular evidence for the sickle cell anemia （SCA） crisis in Nigerian patients arising from parvovirus b19 infection remains inadequate. This study determined the prevalence and correlates of antiparvovirus b19 antibodies in a population of SCA patients and non-SCA healthy controls in Lagos, Nigeria. In this prospective cross-sectional study, we enrolled 73 confirmed SCA patients from 5 district hospitals in Lagos and 81 sex and age-matched non-SCA healthy controls. Serum sample from each study participant was screened for anti-parvovirus b19 by ELISA and PCR techniques. Standard biomedical assays were also done. Anti-parvovirus b19 IgM and IgG antibodies were detected in 22 （14.3%） and 97 （62.9%） of the 154 sera screened, 13 （17.8%） and 45 （61.6%） in SCA patients; 9 （11.1%） and 52 （64.2%） in non-SCA controls. The overall seronegativity rate was 19.5%. Parvovirus B19 DNA was found in 2 （11.1%） of the 18 IgM seropositive SCA serum samples screened. On the whole, parvovirus b19 infection was more commonly asymptomatic in non-SCA controls but caused significant elevation in liver enzymes in infected SCA patients （P 〈 0.05）. The risk of acute parvovirus b19 infection increased 65 times during unsteady state among the SCA patients. Although no deaths of infected patients were recorded during the study, age below 12 years, hospitalization and overcrowded environment were risk factors for infection. We conclude that parvovirus b19 is common in SCA patients, incurring greater susceptibility to infections.

Parvovirus B19 status in liver,kidney and pancreas transplant candidates:A single center experience

BACKGROUND Parvovirus B19(B19V)is associated with a wide range of clinical manifestations.The major presentation is erythema infectiosum.However,a persistent infection may cause pure red cell aplasia and chronic anemia in immunocompromized patients.The B19V seroprevalence varies with age and geographical location.AIM To determine the B19V serological status and DNAemia in kidney,liver,and pancreas transplant candidates.METHODS Patients who underwent kidney,liver,or simultaneous kidney and pancreas/liver transplantation between January 2021 and May 2022 were included in the study.The serum samples were collected before transplantation.For detection of B19V DNA,a LightMix Kit B19V EC(TIB MOLBIOL,Berlin,Germany)was used.B19V IgM and IgG antibodies were detected using a commercial ELISA test(Euroimmun,Lübeck,Germany).RESULTS One hundred and thirty-one transplant candidates were included in the study,71.0%male,with an average age of 53.27 years±12.71 years.There were 68.7%liver,27.5%kidney,3.0%simultaneous pancreas/kidney transplant(SPKT),and 0.8%simultaneous liver/kidney transplant recipients.No patients had detectable B19V DNA.B19V IgG seroprevalence was 77.1%.No acute or recent infections were detected(IgM antibodies).There was no difference in the mean age of seronegative and seropositive patients(51.8 years±12.9 years vs 53.7 years±12.7 years,t=-0.603;P=0.548).Although seropositivity was lower in patients aged less than 30 years(66.6%)compared to the patients aged 30-59 years and>60 years(80.4%and 78.1%,respectively),this difference was not significant.In addition,there was no difference in seropositivity between male and female transplant candidates,76.3%and 78.9%(χ^(2)=0.104;P=0.748).The seroprevalence did not differ among organ recipients,with 77.8%,80.6%,and 50.0%for liver,kidney,and SPKT,respectively,(χ^(2)=5.297;P=0.151).No significant difference was found in the seroprevalence in kidney transplant patients according to dialysis modality.Seroprevalence was 71.1%in hemodialysis patients,and 100%in peritoneal dialysis patients(χ^(2)=0.799;P=0.372).CONCLUSION The B19V seroprevalence is expectedly high among kidney,liver,and pancreas transplant candidates,but there are still 22.9%of seronegative individuals who remain at risk for primary disease and severe manifestations.Further research should elucidate the necessity of B19V screening in peri-transplant management.

Parvovirus B19 and Pregnant Women: A Bibliographic Review

Primary infection with parvovirus B19 is an uncommon but serious and treatable cause of chronic anemia in immuno compromised hosts. Widely distributed, it is responsible for a wide range of clinical manifestations, the characteristics and outcome of which depend on the interaction between the viral properties and the physiological and immune status of the infected individuals. Infection during pregnancy can result in fetal anemia, abortion, and hydrops. Pregnancy does not appear to affect the course of the infection, but the infection may affect the pregnancy. The diagnosis of B19V can be made by serological and molecular investigation of the mother, fetus and newborn. In these conditions, it seemed necessary for us to answer in this article the various questions raised by the occurrence of a contagion and/or an infection with Parvovirus B19 during pregnancy. Our objective was to determine at first the nature and the main characteristics of Parvovirus B19 as well as its propagation during the pregnancy and to show its risk for the pregnant woman and her fetus. The importance of the subject is proven by the data on the spread and incidence of the virus. Worldwide, the focus on pregnancy is due to the additional potentially fatal effects on the fetus. This document covers the important aspects of a medical investigation: causes, symptoms, tests and diagnosis.

Focal seizure associated with human parvovirus B19 infection in a non-encephalopathic child

Background:The incidence of acute symptomatic(at the time of documented brain insult)seizures and single unprovoked seizures are 29-39 and 23-61 per 100000 per year,respectively.After stabilization of the patient,fi nding the etiology of the seizure is of paramount importance.A careful history and physical examination may allow a diagnosis without need for further evaluation.Methods:In the literature,severe central nervous system involvement has been reported from human parvovirus B19 infection.We reported a previously healthy 7-year-old girl who presented after an episode of focal seizure.She was afebrile and didn't have any focal neurological abnormalities.She had erythematous malar rash along with reticulating pattern of rash over her both upper extremities.Results:Parvovirus infection was suspected due to the characteristic erythematous malar rash.Serum human parvovirus B19 DNA polymerase chain reaction was positive which was consistent with acute parvovirus infection.Further confirmation of current infection was done with Sandwich enzyme immunoassays showing positive anti-B19 IgM Index(>1.1).IgG index was equivocal(0.9-1.1).Conclusions:We report an extremely rare presentation of non-febrile seizure from acute parvovirus infection in a child without encephalopathy who had an excellent recovery.Timely diagnosis can provide counselling regarding future seizure recurrence risk,curtail expenditure from expensive diagnostic work up and provide additional recommendations about potential risks to a pregnant caregiver.

Severe Anemia in a Patient With Mild T Cell Hypofunction Infected With Parvovirus B19

Background Parvovirus B19 is a single-stranded DNA virus with a 5.6 kilobase DNA genome and a diameter of 22–24nm.1 This virus does not possess an envelope and it is the most pathogenic virus belonging to the family of Parvoviridae that infects human beings.2 The main diseases caused by parvovirus B19 are as follows:(1)infectious erythema(also known as fifth disease,erythema infection),a cause of a common rash in pediatric patients;(2)joint disease;(3)aplastic anemia crisis in patients with chronic hemolytic disease;(4)chronic anemia in immunodeficient patients;(5)fetal hydrops in addition to stillbirth and abortion(fetal death).

17例人微小病毒B19肝炎患者临床特点分析

目的探讨人微小病毒B19肝炎患者的临床特征。方法对17例感染人微小病毒B19患者的病历资料进行回顾性分析,总结肝损害的特点和临床特征。结果 17例人微小病毒B19肝炎患者均有发热(100%),有全身乏力14例(82.4%)、关节、肌肉痛9例(52.9%)、咽痛6例(35.3%)、食欲减退11例(64.7%)、皮疹5例(29.4%)、脾肿大12例(70.6%),肝肿大7例(41.2%)、淋巴结肿大3例(17.6%)、黄疸5例(29.4%);除血ALT和AST升高外,伴有羟丁酸脱氢酶、乳酸脱氢酶、腺苷脱氨酶升高和淋巴细胞百分比升高;起病急,临床表现复杂,但多呈急性自限性过程,肝功能恢复较快,预后较好。结论对不明原因肝损害同时伴有上述特征者,除常规筛查常见的嗜肝病毒外,及时检测血清抗人微小病毒B19抗体Ig M,能帮助明确一部分患者的病因。