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.

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.

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。

人微小病毒B19感染与自然流产的关系

目的通过分析自然流产与正常妊娠晚期待产孕妇人微小病毒B19(HPV B19)DNA及IgM抗体检测情况,探讨HPV B19与自然流产的关系。方法采集自然流产孕妇(观察组,28例)与正常待产孕妇(对照组,33例)的静脉血,以聚合酶链反应(PCR)法检测HPV B19 DNA,酶联免疫吸附试验(ELISA)检测HPV B19 IgM抗体。结果观察组HPV B19 DNA阳性率为28.57%(8/28),对照组为9.09%(3/33),两组HPV B19DNA阳性率比较,差异有统计学意义(x2=3.98,P<0.05)。观察组检测出1例(3.57%,1/28)HPV B19 IgM抗体阳性,对照组未检测到阳性者(0.00%)。结论自然流产孕妇HPV B19感染率高于妊娠晚期待产孕妇,推测HPV B19感染可能是导致自然流产的原因之一。

人微小病毒B19感染所致肝损害19例临床分析

目的探讨B19病毒感染所致肝损害的临床表现、实验室检查特点及治疗与转归。方法对人微小病毒B19感染患者19例的临床资料进行回顾性分析。结果在人微小病毒B19感染的19例患者,主要症状有乏力(12例)、黄疸(10例)、脾肿大(10例),伴有发热(10例)、皮疹(6例)及肌肉关节疼痛(6例),有6例伴有如下疾病或并发症:如妊娠(1例)、急性肝功能衰竭(2例)、精神分裂症(1例)、急性骨髓停滞(1例)和肺炎(1例)。以血清天门冬氨酸氨基转移梅(AST)升高为主,黄疸大多数表现为轻到中度,容易出现凝血酶原活动度(PTA)下降,但胆碱脂酶(CHE)下降不明显。经积极对症支持治疗,肝功能等各项指标正常后治愈出院。人微小病毒B19可致肝功能受损,导致急性肝炎或急性重型肝炎。结论对临床上非甲～戊型肝炎病人,应注意检查血清抗B19病毒IgM。该病毒感染是一个急性或亚急性过程,呈良性经过,有自愈倾向。

儿童自身免疫性疾病人细小病毒B19感染及其临床特征

目的探讨儿童自身免疫性疾病(AD)人细小病毒B19(B19)的感染情况及其临床特征。方法采用巢式聚合酶链反应(nPCR)技术检测133例AD患儿血清(BS)或骨髓(BM)标本B19-DNA。另设35例健康儿童为对照组。结果AD患儿B19-DNA总阳性率为29.3%,与对照组比较差异有统计学意义(P<0.01)。62例过敏性紫癜(AP)患儿BS标本B19-DNA阳性率20.9%,与对照组比较差异无统计学意义(P>0.05)。30例幼年特发性关节炎(JRA)B19-DNA阳性率40.0%(12/30例),与对照组比较差异有统计学意义(P<0.01);全身型、多关节型和少关节型B19-DNA阳性率依次为44.4%、36.4%和40.4%,两两比较差异无统计学意义(P>0.05)。结论AD可能与B19感染有关,感染的临床表现多种多样;B19感染相关性AP临床表现多样,症状重,关节症状更突出;B19相关性JRA可表现为JRA各型。

人细小病毒B19感染与习惯性流产的关系探讨

目的:探讨人细小病毒B 19(Human parvovirus B 19,HPVB19)感染与习惯性流产(Recurrent pregnancy loss,RPL)的关系。方法:建立人细小病毒B 19巢式聚合酶链反应(Nested Polymerase chain reaction,NestedPCR)检测方法,采集习惯性流产孕妇流产组织和正常妊娠人工流产组织,用巢式PCR方法检测流产组织中HPV B 19 DNA。结果:56例RPL孕妇流产组织中HPVB 19 DNA有16例阳性,阳性率28.6%,50例正常妊娠人工流产组织中HPVB19 DNA有2例阳性,阳性率4.0%,2组HPV B19感染率有显著性差异(χ2=12.38,P<0.01)。流产次数与HPV DNA阳性率无显著性关系(χ2=0.03,P>0.05)。结论:RPL孕妇HPV B 19感染率显著高于正常孕妇,HPV B 19感染可能导致习惯性流产的发生。