Fetal parvovirus B19 infection and liver disease of antenatal onset in an infant with Ebstein's anomaly

Evaluation of Molecular Test for the Discrimination of "Naked" DNA from Infectious Parvovirus B19 Particles in Serum and Bone Marrow Samples

Low levels of parvovirus B19 (B19V) DNA can be detected in the circulation and in different tissue of immunocompetent individuals for months or years, which has been linked to inflammatory diseases such as cardiomyopathy, rheumatoid arthritis, hepatitis, and vasculitis. However, the detection of B19V DNA does not necessarily imply that infectious virions are present. This study aimed to evaluate the method based on the Benzonase^® treatment for differentiation between the infectious virions from “naked” DNA in serum and bone marrow (BM) samples to be useful for the B19V routine diagnosis. In addition, we estimated the period of viremia and DNAemia in the sera and bone marrow of nonhuman primates experimentally infected with B19V. Serum samples from ten patients and from four cynomolgus monkeys experimentally infected with B19V followed up for 60 days were used. Most of the human serum samples became negative after pretreatment; however, only decreased viral DNA loads were observed in four patients, indicating that these samples still contained the infectious virus. Reduced B19V DNA levels were observed in animals since 7th dpi. At approximately 45th dpi, B19V DNA levels were below 10⁵ IU/mL after Benzonase^® pretreatment, which was not a consequence of active B19V replication. The test based on Benzonase^® pretreatment enabled the discrimination of “naked DNA” from B19V DNA encapsidated in virions. Therefore, this test can be used to clarify the role of B19V as an etiological agent associated with atypical clinical manifestations.

Identification and management of congenital parvovirus B19 infection

Parvovirus B19 (B19V) infection is well known for its mild, self-limiting clinical presentations in children, such as erythema infectiosum. Approximately 40% of women of childbearing age are susceptible to B19V infection. While maternal B19V infection usually has a good prognosis, B19V can cause severe fetal anaemia and pregnancy loss due to its ability to suppress erythroid progenitor cells. Non-invasive ultrasound monitoring for fetal anaemia is usually performed if maternal seroconversion occurs in the first 20 weeks of gestation, with amniocentesis for fetal infection reserved for those who first present with fetal anaemia or hydrops of unknown cause. Intrauterine transfusion is the standard treatment for severe fetal anaemia and is associated with a significant improvement in survival. However, survivors of hydrops fetalis may have a higher rate of long-term neurodevelopmental complications compared with non-hydropic survivors. This review aims to synthesise published data on the diagnosis, surveillance and outcomes of congenital parvovirus infection to assist clinicians in diagnosing and managing this important condition.

Parvovirus B19 infection during pregnancy and risks to the fetus

Parvovirus B19 infects 1 to 5% of pregnant women, generally with normal pregnancy outcomes. During epidemics, the rate of infection is higher. Major congenital anomalies among offspring of infected mothers are rare, as the virus does not appear to be a significant teratogen. However, parvovirus B19 infection may cause significant fetal damage, and in rare cases, brain anomalies and neurodevelopmental insults, especially if infection occurs in the first 20 weeks of pregnancy. Parvovirus B19 is also an important cause of fetal loss, especially in the second half of pregnancy when spontaneous fetal loss from other causes is relatively rare. Parvovirus B19 infection may affect many fetal organs and can cause severe anemia, following fetal erythroid progenitor cells infection and apoptosis, especially in fetuses, that have shortened half-life of erythrocytes. Severe anemia may cause high output cardiac failure and nonimmune hydrops fetalis. In addition, parvovirus B19 may directly infect myocardial cells and produce myocarditis that further aggravates the cardiac failure. Intrauterine fetal transfusion is commonly used for the treatment of severe fetal anemia with survival rates of 75 to 90% and significant reduction of fetal morbidity. Only 66 cases were evaluated neurodevelopmentally, of which 10 (16%) had slight or severe neurodevelopmental problems. Because parvovirus B19 infection can cause severe fetal morbidity and mortality, it should be part of the routine work-up of pregnant women who have been exposed to the virus or of pregnancies with suspected fetal hydrops. Assessment for maternal infection during pregnancy is especially important during epidemics, when sero-conversion rates are high. Birth Defects Research 109:311-323, 2017. © 2017 Wiley Periodicals, Inc.

The magnitude and correlates of Parvovirus B19 infection among pregnant women attending antenatal clinics in Mwanza, Tanzania

Background

Human parvovirus B19 (B19) infection has been associated with congenital infection which may result into a number of the adverse pregnancy outcomes. The epidemiology and the magnitude of B19 infections among pregnant women have been poorly studied in developing countries. This study was done to establish preliminary information about the magnitude of B19 among pregnant women attending antenatal clinics in the city of Mwanza, Tanzania.

Methods

A cross-sectional study was conducted between December 2014 and June 2015 among 258 pregnant women attending two antenatal clinics representing rural and urban areas in the city of Mwanza. Socio-demographic data were collected using structured data collection tool. Specific B19 IgM and IgG antibodies were determined using indirect enzyme linked immunosorbent assay kits (DRG Instruments GmbH, Germany). Data were analyzed using STATA version 11 software.

Results

The median age of study participants was 21 IQR (19–25) years. Of 253 pregnant women; 116(44.96%), 109(42.25%) and 33(12.79%) were in the first, second and third trimester respectively. The majority 168(66.4%) of women were from urban areas. Of 253 pregnant women, the overall prevalence of IgM was 83(32.8%) while that of IgG was 142(55.0%) among 258 women tested. A total of 50(19.4%) women were positive for both IgG and IgM indicating true IgM positive. History of baby with low birth weight (OR: 10, 95% CI: 1.82–58.05, P = 0.01) was independent predictor of B19 IgG seropositivity and being at the third trimester was protective (OR: 0.38, 95% CI: 0.16–0.92, P = 0.03). The IgG titers were found to decrease significantly as gestational age increases (Spearman’s rho = −0.2939, p = 0.0004)

Conclusion

More than a half of pregnant women in Mwanza city are B19 IgG sero-positive with about one third of these being B19 IgM seropositive. Further studies to determine the impact of B19 infections among pregnant women and their newborns are recommended in developing countries.

Human Parvoviruses

Parvovirus B19 (B19V) and human bocavirus 1 (HBoV1), members of the large Parvoviridae family, are human pathogens responsible for a variety of diseases. For B19V in particular, host features determine disease manifestations. These viruses are prevalent worldwide and are culturable in vitro, and serological and molecular assays are available but require careful interpretation of results. Additional human parvoviruses, including HBoV2 to -4, human parvovirus 4 (PARV4), and human bufavirus (BuV) are also reviewed. The full spectrum of parvovirus disease in humans has yet to be established. Candidate recombinant B19V vaccines have been developed but may not be commercially feasible. We review relevant features of the molecular and cellular biology of these viruses, and the human immune response that they elicit, which have allowed a deep understanding of pathophysiology.

Viral diseases of the liver in children: diagnostic and differential diagnostic considerations

This review summarizes the general histologic features of acute and chronic hepatitides and highlights those morphologic findings that may suggest or be diagnostic of a specific agent or etiology. The main epidemiologic, clinical, and pathologic features of the hepatotropic viruses are discussed, with an emphasis on pediatric studies and the differential diagnosis of hepatitis in childhood.

Cytomegalovirus and human herpesvirus 6, but not human papillomavirus, are present in neonatal giant cell hepatitis and extrahepatic biliary atresia

The purpose of our study was to confirm reports of an association of human papillomavirus (HPV) with neonatal giant cell hepatitis (GCH) and biliary atresia (BA), and to expand these studies to include cytomegalovirus (CMV), Epstein-Barr virus (EBV), human herpesvirus 6 (HHV6), and parvovirus B19 (PVB19). Frozen hepatic tissue was available for polymerase chain reaction (PCR) analysis in 19 cases of GCH or BA and 8 controls. Nested PCR to detect HPV types 6, 16, 18, and 33 was followed by 32P hybridization with generic probes. PCR followed by hybridization with a digoxigenin-labeled probe was used for all other viruses. HPV, EBV, and PVB19 were not detected in cases or controls. Two cases of GCH and 1 case of BA were PCR positive for CMV; controls were negative. HHV6 was detected in 6 cases: 2 GCH, 2 BA, and 2 controls. We conclude that HPV is not associated with GCH or BA. Detection of CMV in BA and GCH confirms other reports of this association. HHV6 requires further study to determine the significance of a positive PCR test in the livers of infants.

Acute glomerulonephritis after human parvovirus B19 infection

We evaluated clinical and histological characteristics of four adult patients who presented with acute glomerulonephritic syndrome with serological confirmation of recent HPB19 infection. All patients had generalized edema with urinary abnormalities. Body weight gain ranged from 3 to 10 kg. Three of the patients had contact with erythema infectiosum simultaneously with or within 10 days before development of flu-like symptoms. Two patients had an erythematous rash, and one patient had lower-extremity purpura. Joint pain was present in three of the patients. All patients had proteinuria and hematuria. Renal functions were normal except in one patient who had a serum creatinine of 3.2 mg/dL. Three of the patients had hypocomplementemia. All renal biopsy specimens were characterized by glomerular leukocyte infiltration and endothelial cell swelling. Mesangiolysis was seen in three of the patients. C3 was deposited in a coarse granular pattern along the capillary walls in all cases. Electron microscopic examination showed marked expansion of the subendothelial space of glomerular capillaries in all patients. Subendothelial electron-dense deposits were present in all patients. Immunohistochemical analysis using monoclonal anti-HPB19 antibody showed that one of the four patients had positive staining in the glomeruli. DNA extracted from renal biopsy specimens contained HPB19 DNA, as shown by polymerase chain reaction (PCR) analysis in all patients. PCR amplification of the renal DNA generated a 104-bp product, which hybridized to an HPB19-specific probe. No control group subjects contained HPB19 DNA as determined by PCR. This circumstantial evidence indicates that HPB19 infection may be one of the causes of acute glomerulonephritis in normal individuals.

The incidence of, and factors leading to, parvovirus B19-related hydrops fetalis following maternal infection; report of 10 cases and meta-analysis

OBJECTIVES

to clarify the approximation of the frequency of B19-related nonimmune hydrops fetalis (NIHF), and to know the critical period during which maternal infection led to NIHF.

METHODS

we investigated the characteristics of 10 cases of antenatal B19 infection diagnosed over the past 10 years in Miyagi prefecture, Japan, and performed a meta-analysis of these cases and those previously reported in the literature.

RESULTS

NIHF caused by intrauterine B19 infection was diagnosed between 11 and 23 weeks of gestation in 10 women over the past 10 years in Miyagi prefecture, Japan. The source of infection was the mother's older child in six out of 10 cases, and children at a kindergarten where the mothers worked in two cases. The interval between the onset of infection and the diagnosis of NIHF ranged from 2 to 6 weeks. B19 infection was responsible for 10 (15.2%) in 66 cases of aetiology unknown NIHF in this study, and for 57 (19.1%) of 299 cases of non-malformed or aetiology-unknown NIHF by meta-analysis of the literature. Meta-analysis of the 165 reported cases of antenatal B19 infection, including the 10 cases described above, showed that there was a 10.2% excess risk of fetal death in women infected with B19 during pregnancy and a 12.40% excess risk in women infected during the first 20 weeks of pregnancy. Transplacental transmission was confirmed in 69 (24.1%) of 286 cases. The mean gestational age at diagnosis of NIHF was 22.8 +/- 5.1 weeks. The mean interval between the onset of maternal infection and diagnosis of NIHF was 6.2 +/- 3.7 weeks.

CONCLUSIONS

these approximations will be useful for counselling and management for pregnant women. The critical period during which maternal infection led to NIHF correlated with the hepatic period of hematopoietic activity. These findings suggest that parvovirus B19 may have an affinity for erythroid lineage cells at the hepatic stage of hematopoiesis, which may strongly influence the clinical features of feto-maternal B19 infection.

Feto-placentary pathology in human parvovirus B19 infection

In view of the scarce references concerning the histological data in congenital parvovirus human B19 infection, we intend to provide a description of the pathological features observed in six autopsies. The virus was detected by DNA hybridization (ISH-DBH), PCR and electronmicroscopy (EM) in paraffin-embedded feto-placentary tissues. These cases constitute a subset from 86 Non Immunologic Hydrops Fetalis (NIHF) cases, in which a systemic complex of inflammatory/degenerative lesions of unknown etiology was visualized by optical microscopy. In one case a syphilitic process was detected, typefying a double infection. All fetuses showed a similar pathology--hydrops, hepato-splenomegaly, lung hypoplasia and erythroblastemia, the specific histological feature being the presence of intranuclear inclusions in the erythroid progenitors, in the erythropoietic visceral tissue and in blood marrow. Complex cardiopathy allied to abnormal lung lobulation and polisplenia were observed once; in 2 cases endocardial fibroelastosis was diagnosed. The pulmonary lesions were represented by dysmaturity allied to interstitial mononuclear infiltration. The hepatic consisted of cholestasis, portal fibrosis, canalicular proliferation, hemossiderosis, focal necroses and giant cell transformation. The central nervous system lesions were predominantly anoxic although the autolysis impaired a correct diagnosis.

Association of parvovirus B19 genome in children with myocarditis and cardiac allograft rejection: diagnosis using the polymerase chain reaction

BACKGROUND

Inflammatory diseases of the heart, including myocarditis and cardiac transplant rejection, are important causes of morbidity and mortality in children. Although viral infection may be suspected in either of these clinical conditions, the definitive etiology is often difficult to ascertain. Furthermore, the histology is identical for both disorders. Coxsackievirus has long been considered the most common cause of viral myocarditis; however, we previously demonstrated by polymerase chain reaction (PCR) analysis that many different, and sometimes unexpected, viruses may be responsible for myocarditis and cardiac rejection. In this study, we describe the association of parvovirus genome identified through PCR analysis of cardiac tissue in the clinical setting of myocarditis and cardiac allograft rejection.

METHODS AND RESULTS

Myocardial tissue from endomyocardial biopsy, explant, or autopsy was analyzed for parvovirus B19 using primers designed to amplify a 699-base pair PCR product from the VP1 gene region. Samples tested included those obtained from patients with suspected myocarditis (n=360) or transplant rejection (n=200) or control subjects (n=250). Parvoviral genome was identified through PCR in 9 patients (3 myocarditis; 6 transplant) and no control patients. Of the 3 patients with myocarditis, 1 presented with cardiac arrest leading to death, 1 developed dilated cardiomyopathy, and the other gradually improved. Four of the 6 transplant patients had evidence of significant rejection on the basis of endomyocardial biopsy histology. All transplant patients survived the infection.

CONCLUSIONS

Parvovirus is associated with myocarditis in a small percentage of children and may be a potential contributor to cardiac transplant rejection. PCR may provide a rapid and sensitive method of diagnosis.

Identification of human parvovirus B19 infection in idiopathic nonimmune hydrops fetalis

OBJECTIVE

This retrospective study was designed to determine the incidence of B19 associated with idiopathic nonimmune hydrops fetalis by use of a sensitive molecular tool, the polymerase chain reaction assay.

STUDY DESIGN

Placental and fetal tissues from 57 cases of nonimmune hydrops fetalis were analyzed for B19 deoxyribonucleic acid. Thirty-four of these cases were classified as idiopathic. The remaining 23 cases had known, noninfectious-based causes.

RESULTS

Eighteen percent of all cases (6/34) of idiopathic nonimmune hydrops fetalis contained B19 deoxyribonucleic acid. In contrast, none of the 23 cases of known, noninfectious-based nonimmune hydrops fetalis examined contained any B19 deoxyribonucleic acid. Presence of the virus was confirmed in each of the six cases by either B19-specific deoxyribonucleic acid in situ hybridization or immunocytochemistry. However, histologic examination was unsuccessful at detecting characteristic viral-like inclusions in one third of the cases.

CONCLUSION

Eighteen percent of cases of idiopathic nonimmune hydrops fetalis contained B19 deoxyribonucleic acid. This significant finding demonstrates the usefulness of polymerase chain reaction to aid in the differential diagnosis of this disease.