Diagnosis and incidence of fetal parvovirus infection in an autopsy series: II. DNA amplification

Diagnosis of in utero Parvovirus B19 infection and maternal immune response - the relevance of linear epitopes and advanced serologic testing

IMPORTANCE OF THE FIELD

Parvovirus B19 (B19V) infection in utero causing fetal anemia and non-immune hydrops fetalis (NIHF) is a potentially life-threatening event for the fetus. Postexpositional non-invasive diagnosis is based on maternal IgG/IgM response and detection of viral genome in maternal blood. Serologic testing directs prenatal follow-up. Fetal infection is confirmed by polymerase chain reaction or in situ hybridization in fetal blood and/or amniotic fluid cells. The performance of serologic tests is significant in order to direct pre- and perinatal care at rational use of resources. Timing of diagnostic procedures and knowledge of the time course of infection in pregnant, asymptomatic women are critical. IgM negative testing in the presence of prolonged viremia may complicate individual risk analysis in pregnancy. Recently, advanced IgG avidity assays and epitope-type specific assays (IgG ETS EIA) have been re-evaluated.

AREAS COVERED IN THIS REVIEW

Epidemiology, clinical relevance and management of B19V infection in pregnancy. A review of the current literature (November 1984 - May 2009) and evaluation of current information on performance and predictive value of molecular and VP1/VP2 antigen-based IgG tests directed at the diagnosis of materno-fetal B19V infection and detection of past immunity. New aspects of B19V-associated fetal disease other than anemia/NIHF are also covered.

WHAT THE READER WILL GAIN

An overview of immunology and clinical relevance of B19V infection in pregnancy, of the potential value of advanced serologic testing and fields of future research.

TAKE HOME MESSAGE

In the absence of a commercially available vaccine, serologic tests remain important tools in individual risk analysis of pregnant women exposed to B19V. Sequential application of IgG avidity and IgG ETS EIAs may improve risk stratification and timing of invasive testing in B19V-exposed pregnancies, in particular with IgM-negativity and/or persistent DNAemia. Prospective evaluation of these test systems correlated to fetal outcome in order to reduce fetal morbidity and mortality as well as the overall burden of disease of B19V with regard to fetal malformation may be subject to future research.

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.

Detection of parvovirus B19 IgM by antibody capture enzyme immunoassay: receiver operating characteristic analysis

Parvovirus B19 infection can cause severe effects in high-risk groups including pregnant women and immunocompromised individuals. Although serological detection of B19 infection is commonplace, minimal information is available on the absolute performance characteristics of various tests for the detection of B19 IgM. The performance of the first parvovirus B19 IgM enzyme immunoassay to be cleared by the US Food and Drug Administration (FDA) is described. The immunoassay cut-off has been established using receiver operating characteristic (ROC) analysis giving a sensitivity and specificity of detection of 89.1 and 99.4%, respectively. No cross-reactivity is observed with rubella or other viral disease IgM which cause similar symptomologies to parvovirus B19. Multi-site reproducibility studies have shown high immunoassay reproducibility with detection rates (observed/expected result) of 100% for nonreactive specimens (N=324) and strongly reactive (N=403), respectively. Immunoassay reproducibility ranged from 11.76 to 17. 46% coefficient of variation for all reactive specimens tested (N=12) whereby each specimen was assayed a total of 81 times. Parvovirus B19 IgM seroprevalence of 1% was observed in a US blood donor population (N=399). In the absence of international performance criteria, this study will be of major benefit to the clinical virologist in assessing immunoassay reliability for the detection of recent infection with parvovirus B19.

Investigation of nonimmune hydrops fetalis: multidisciplinary studies are necessary for diagnosis--review of 94 cases

This review of 94 cases of nonimmune hydrops fetalis (NIHF) over a 10-year period was undertaken to evaluate the frequency of this pathology among fetal and infant deaths and to determine the most common likely etiologies in a northeastern region of France. NIHF represented 6% of the fetal deaths examined in our laboratory. The combination of findings from morphologic examination of the placenta and fetus with the results of microbiological and cytogenetic investigations (conventional cytogenetic study, fluorescent in situ hybridization [FISH], or DNA ploidy image analysis) led to an etiologic diagnosis for NIHF in two-thirds of the cases and suggested a diagnosis in an additional 23% of cases. The most common causes of NIHF were chromosome abnormalities (33%), infections (16%), and cardiac pathology (13.8%). The detection of a cause for NIHF is important for genetic counseling and management of subsequent pregnancies. Our experience suggests that a diagnosis is possible in a large majority of NIHF when obstetricians and pathologists carefully coordinate the management of prenatal and postnatal investigations and when new techniques, such as molecular biology and DNA quantification, are used.

Serologic study of human parvovirus B19 infection in pregnancy in Japan

OBJECTIVES

To clarify the relationship between hydrops fetalis and parvovirus outbreaks in the community, seroprevalence of B19 antibody among women of childbearing age, and adverse effects of intrauterine B19 infection.

METHODS

Sera were collected from 168 cases of hydrops fetalis which were diagnosed between 1987 and 1997 in Miyagi prefecture, Japan, from 232 healthy pregnant women in 1987 and 277 healthy pregnant women in 1997 in Miyagi, and from 48 women infected with B19 during pregnancy. The sera were examined for B19 IgG and IgM antibodies by enzyme-linked immunosorbent assay and for B19 DNA by polymerase chain reaction. The number of cases of erythema infectiosum in Miyagi had been monitored each month.

RESULTS

Thirteen of the 168 cases of hydrops fetalis were found to be caused by intrauterine B19 infection and 12 of the 13 cases clustered in two periods of outbreaks of erythema infectiosum in the community. The positive rates of B19 IgG antibody between 1987 and 1997 were significantly different: 33% in 1987 and 46% in 1997. Nine of the 48 women infected during pregnancy showed adverse effects of the fetus: eight hydrops fetalis and one early abortion with positive B19 DNA. The fetal death rate (>12 weeks of gestation) among them was 15% (7/48), far higher than the calculated 1% among the general population. The nine mothers with adverse fetal outcomes had contact with the infectious source at the 16 weeks of gestation or earlier.

CONCLUSIONS

These data clearly showed a relationship between hydrops fetalis and parvovirus outbreaks in the community, and it may be important to follow the seroprevalence for an extrapolated period time to predict occurrence of hydrops fetalis caused by B19. Also the data indicated that the gestational week infection occurred is the most important determinant of an adverse effect to the fetus as described previously.

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.

Fetal pathology in intrauterine death due to parvovirus B19 infection

OBJECTIVES

To study the pathological features of fetuses dying because of parvovirus B19 infection, with particular reference to the presence of hydrops; to assess the usefulness of immunochemistry as a screening method for the detection of parvovirus infection at post-mortem examination.

DESIGN

Review of clinical, sonographic, serological and pathological data; immunohistochemical staining of post-mortem tissue.

SAMPLE

Cases of intrauterine fetal death occurring during the 18-month period January 1993 to June 1994 inclusive, referred for post-mortem examination to the Pathology Department, Royal Victoria Infirmary, Newcastle upon Tyne.

RESULTS

Eleven cases of fetal death due to parvovirus infection were identified. Seven fetuses were less than 18-week size. Three fetuses showed conspicuous hydropic change. One of the 11 cases was detected for the first time by retrospective immunochemical screening. Of cases originating from the Newcastle district, parvovirus infection was responsible for about 10% of all non-malformed fetal deaths occurring between 10 and 24 weeks of gestation referred for pathological examination.

CONCLUSIONS

During the period of study, parvovirus infection was a relatively common cause of mid-trimester fetal death. Many fetuses dying because of this infection are not noticeably hydropic, and the possibility of parvovirus infection should be considered in any case of intrauterine fetal death. Immunochemistry can be used to confirm the histopathological diagnosis, and may be of particular help where there is advanced autolysis; immunohistochemical screening may detect occasional cases not initially identified by examination of routinely stained tissue sections.

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.

Retrospective diagnosis of sickle cell-hemoglobin C disease and parvovirus infection by molecular DNA analysis of postmortem tissue

A previously healthy 30-year-old African-American woman presented with a history of sickle cell trait and a nonspecific prodromal illness with severe bone pain. She experienced rapid clinical deterioration with seizures and cardiorespiratory arrest leading to death. Autopsy showed necrotic bone marrow with extensive bone marrow emboli. Parvovirus infection was documented by polymerase chain reaction (PCR) although diagnostic intranuclear inclusions or giant pronormoblasts were not present. The diagnosis of sickle cell-hemoglobin C disease (hemoglobin SC disease) was also established postmortem by DNA sequencing of PCR products. This case illustrates the use and versatility of PCR for analysis of formalin-fixed paraffin-embedded autopsy tissue.

Immunohistochemical distribution of surfactant apoproteins in hypoplastic lungs of nonimmunologic hydrops fetalis

Forty-three patients with nonimmunologic hydrops fetalis (NIHF), including 32 patients (74%) with hypoplastic lung, were immunohistochemically examined for the expression of surfactant apolipoproteins (SPs), using anti-gamma G immunoglobulins against human SP-A with a molecular weight (MW) of 35 K and SP-B with a MW of 5 K compared with that in 59 patients in a control group and 45 patients with hypoplastic lung induced by causes other than NIHF. In the control group, SP-A was expressed in the lungs from 23 gestational weeks and became more numerous and intense in alveolar type II cells after 31 gestational weeks, whereas SP-B began to be expressed from 20 gestational weeks, and almost all patients showed a diffuse positivity after 26 gestational weeks. In the NIHF group, SP-A expression was generally weak, even after 31 gestation weeks. Moreover, most of the patients showing a weak expression of SP-A were also associated with hypoplastic lung and had a clinical history of persistent intrauterine pleural effusion of more than 2 weeks. Conversely, the immunoreactivity of SP-B was well preserved in NIHF cases either with or without hypoplastic lung. These results suggest that in the NIHF lung, there is a possible delay in the functional maturation or development of SP-A synthesis by alveolar type II cells, and this retardation of the functional maturation in type II cells also participates in the postnatal respiratory insufficiency in NIHF.

Parvovirus: the expanding spectrum of disease

Treatment of parvovirus infections among immunocompromised hosts using immunoglobulin has provided the clinician with a useful therapeutic tool but has also highlighted the problems concerning chronic disease states. The discovery of the human parvovirus B19 in 1975 and subsequent studies of its effects in humans have identified this virus as the causative agent of a broad spectrum of diseases. Recent improvements regarding the development of sensitive PCR techniques and methods for cultivation have provided new insight into its pathogenic role, its virology and immunology, and the varied clinical manifestations. The current state of knowledge concerning parvovirus enabled us to divide the long list of diseases caused by this virus into three main categories: (1) disease found among normal hosts (asymptomatic disease, erythema infectiosum, arthropathy, hydrops fetalis), (2) hematologic diseases (aplastic crisis, chronic anemia, idiopathic thrombocytopenic purpura, transient erythroblastopenia of childhood, Diamond-Blackfan anemia) and, finally, (3) a heterogeneous group of diseases, in which the etiologic role of parvovirus is less clear and sometimes putative (neurologic disease, rheumatologic disease, vasculitic and myocarditic syndromes). In particular, arthropathy, hydrops fetalis and the hematologic disorders may be of pediatric concern. Consequently, it is of paramount importance that in all of these cases the clinician includes parvovirus as a differential diagnosis.

Pathology of chronic herpes infection associated with seizure disorder: a report of two cases with tissue detection of herpes simplex virus 1 by the polymerase chain reaction

Although uncommon, the association of chronic encephalitis with epilepsy is well recognized. While a viral etiology has been suspected based on the morphology, to date no virus has been successfully cultured from the brain in patients with Rasmussen's encephalitis. We describe the pathologic findings and report the detection of herpes simplex virus 1 (HSV1) in the brain in two patients who presented primarily with intractable seizures. In the first patient, an intrauterine infection was suspected as the underlying basis for the seizure disorder and the extensive cerebral calcification and gliosis. The second patient (with presumed HSV1 encephalitis at age 7 months) underwent a temporal lobectomy for medically refractory seizures at the age of 3 years and pathologic examination revealed a chronic encephalitis. While immunohistochemical, ultrastructural, and culture studies were negative for viral pathogens, molecular analysis by the polymerase chain reaction (PCR) revealed HSV1 DNA sequences in both cases. Thus our cases represent two examples of chronic encephalitis associated with a seizure disorder, where a definitive viral etiology was documented by PCR.