Comparison of 4 commercial enzyme immunoassays for serology testing of human parvovirus B19 infection.

BACKGROUND: Parvovirus B19 is a pathogenic virus often diagnosed by serology, yet little is known about analytical performance of commercial enzyme immunoassays (EIAs). OBJECTIVE: To investigate performance of 4 EIAs for parvovirus B19 IgM and IgG: Liaison, Euroimmun, Mikrogen and Virion/Serion. STUDY DESIGN: To compare 4 EIAs to Biotrin's ELISA on 168 samples and determine consensus score for discordant samples using Mikrogen's confirmatory line assay. RESULTS: Two thirds of results for IgM/IgG were identical for all 4 EIAs and Biotrin. Liaison shows the highest IgM sensitivity, but has low specificity. Euroimmun lacks IgM sensitivity. Mikrogen had a good overall performance, but had the lowest IgG specificity. Virion/Serion had variable performance with a low IgM specificity and the most borderline and cross-reactive results. CONCLUSIONS: Liaison and Mikrogen have similar performance to Biotrin's ELISA. Euroimmun lacks sensitivity and Virion/Serion produced many borderline and cross-reactive results.

Myocarditis and inflammatory cardiomyopathy: current evidence and future directions.

Inflammatory cardiomyopathy, characterized by inflammatory cell infiltration into the myocardium and a high risk of deteriorating cardiac function, has a heterogeneous aetiology. Inflammatory cardiomyopathy is predominantly mediated by viral infection, but can also be induced by bacterial, protozoal or fungal infections as well as a wide variety of toxic substances and drugs and systemic immune-mediated diseases. Despite extensive research, inflammatory cardiomyopathy complicated by left ventricular dysfunction, heart failure or arrhythmia is associated with a poor prognosis. At present, the reason why some patients recover without residual myocardial injury whereas others develop dilated cardiomyopathy is unclear. The relative roles of the pathogen, host genomics and environmental factors in disease progression and healing are still under discussion, including which viruses are active inducers and which are only bystanders. As a consequence, treatment strategies are not well established. In this Review, we summarize and evaluate the available evidence on the pathogenesis, diagnosis and treatment of myocarditis and inflammatory cardiomyopathy, with a special focus on virus-induced and virus-associated myocarditis. Furthermore, we identify knowledge gaps, appraise the available experimental models and propose future directions for the field. The current knowledge and open questions regarding the cardiovascular effects associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection are also discussed. This Review is the result of scientific cooperation of members of the Heart Failure Association of the ESC, the Heart Failure Society of America and the Japanese Heart Failure Society.

Parvovirus B19 infection and kidney injury: report of 4 cases and analysis of immunization and viremia in an adult cohort of 100 patients undergoing a kidney biopsy.

BACKGROUND: The seroprevalence of human Parvovirus B19 (PVB19) is 70-85% in adults worldwide. PVB19 is the etiologic agent of the fifth disease, is a cause of aplastic anemia, and can be associated with kidney injury. We aimed to describe the cases of 4 patients with kidney injury related to PVB19 primary infection, and to evaluate the seroprevalence of PVB19 and the incidence of PVB19 primary infection in patients undergoing a native kidney biopsy. METHODS: Cases of PVB19 infection with kidney injury were reviewed from the archives of the department of Nephrology. A systematic screening of anti-PVB19 IgG and IgM antibodies and viral DNA was performed in sera from 100 consecutive patients with a kidney biopsy in 2017-2018. RESULTS: The 4 patients with PVB19 infection-associated kidney disease displayed: one lupus-like glomerulonephritis (GN) without lupus auto-antibodies, one minimal change disease with tubular necrosis, one secondary hemolytic and uremic syndrome and one membrano-proliferative GN. In the 100 patients biopsied, 67 had elevated anti-PVB19 IgG, among whom 8 had elevated IgM, without circulating viral DNA, without any particular renal pathological pattern. One additional patient showed a seroconversion at the time of kidney biopsy, which revealed a class V lupus nephritis. CONCLUSION: PVB19 primary infection can be associated with different kidney diseases. The seroprevalence of PVB19 among patients with a kidney biopsy is similar to the overall population, and primary infection is rarely documented (1%) after systematic screening. Whether PV19 is nephrotoxic, or triggers renal endothelial injury and immune activation, remains to be elucidated.

Pure Red Cell Aplasia and Antibody-Mediated Rejection: Double Trouble in 1 Kidney Transplant Recipient Solved by Intravenous Immunoglobulin Infusion: A Case Report.

Acquired pure red cell aplasia (PRCA) is characterized by severe normocytic (rarely macrocytic) and normochromic anemia, a low reticulocytes count in peripheral blood, and near absence of erythroid precursors in the bone marrow, with a normal level of erythropoietin. We describe a case of the kidney transplant recipient, diagnosed with PRCA induced with parvovirus B19 infection. Our case demonstrates that although this complication is rare, it should be considered in a differential diagnosis of anemia diagnostics in immunocompromised patients. In our case reduced immune response resulted from post-transplant immunosuppressive therapy. In our patient, apart from infection by parvovirus B19, graft dysfunction due to polyomavirus BK virus infection was also detected together with histologic and serologic features of antibody-mediated renal graft rejection. Considering the entire clinical picture, intravenous immunoglobulin therapy (IVIg) was successfully introduced.

Successful re-transplantation in patient with recurrent parvovirus B19 pure red cell aplasia.

Impaired cell-mediated, as well as antibody-mediated immunity predisposes a renal transplant recipient to a wide variety of atypical infection. With an increasing number of re-transplant, the balance between immunosuppression and the risk of recurrent disease poses a clinical and therapeutic challenge. Here, we report a successful re-transplantation in a case of parvovirus B19 infection leading to anaemia and collapsing glomerulopathy in the allograft managed with intravenous immunoglobulin (IVIG) and reduction of immunosuppression. This case emphasizes re-consideration to renal transplant after clearance of the virus in a previous renal allograft lost to PVB19 infection.

Febrile neutropenia following parvovirus B19 infection and cross anti-kell reaction to E. coli in pregnancy / Infeção por parvovírus B19 causando neutropenia febril e reação cruzada anti-Kell com E. coli na gravidez

Abstract Parvovirus B19 has tropism for red line blood cells, causing immune hydrops during pregnancy. A positive anti-Kell Coombs reaction usually happens during pregnancy when there is production of antibodies that target Kell antigens, but cross reactions to other antigens may occur. A 24-year-old Gypsy primigravida, 0 Rhesus positive, presented with persistent isolated hyperthermia for 2 weeks and a positive indirect Coombs test result with anti-Kell antibodies at routine tests. She had a 19-week live fetus. The blood tests revealed bicytopenia with iron deficiency anemia, leucopoenia with neutropenia, and elevated C-reactive protein. She was medicated with imipenem, and had a slow clinical recovery. Blood, urine and sputum samples were taken to perform cultures and to exclude other systemic infections. Escherichia coli was isolated in the urine, which most probably caused a transient cross anti-Kell reaction. Haemophilus influenza in the sputum and seroconversion to parvovirus B19 was confirmed, causing unusual deficits in the white cells, culminating in febrile neutropenia. Despite the patient's lack of compliance to the medical care, both maternal and fetal/neonatal outcomes were good. This a rare case report of 2 rare phenomena, a cross anti-Kell reaction to E. coli and parvovirus B19 infection with tropism for white cells causing febrile neutropenia, both events occurring simultaneously during pregnancy.

Resumo O parvovírus B19 tem tropismo para as células sanguíneas da linha vermelha, causando hidropsia imune durante a gravidez. O teste Coombs anti-Kell positivo ocorre durante a gravidez quando há produção de anticorpos contra os antígenos de Kell, mas pode haver reações cruzadas para outros antígenos. Uma grávida primigesta de etnia cigana, de 24 anos, 0 Rhesus positivo, recorreu ao hospital às 19 semanas de gestação por hipertermia isolada persistente por 2 semanas e umteste Coombs indireto positivo por anticorpos anti-Kell em testes de rotina da gravidez. O estudo analítico revelou bicitopenia com anemia ferropênica, leucopenia com neutropenia, e elevação da proteína C-reativa. A paciente foi medicada com imipenem, e teve uma recuperação clínica lenta. Foram colhidas amostras de sangue, urina e expectoração para culturas bacterianas. Na urina, foi isolada Escherichia coli, o que provavelmente causou a reação anti-Kell cruzada transitória. Na expectoração, foi isolada Haemophilus influenza, e foi confirmada seroconversão para o parvovírus B19, que causou um déficit incomum na linhagem sanguínea branca, culminando com neutropenia febril. Apesar da má adesão aos cuidados médicos, os desfechos materno e fetal/neonatal foram bons. Este é um caso de 2 fenômenos raros, uma reação cruzada anti-Kell à infecção por E. coli, e parvovírus B19 comtropismo para células brancas causando neutropenia febril, ambos ocorrendo simultaneamente durante a gravidez.

Pure red cell aplasia.

Pure red cell aplasia (PRCA) is a syndrome defined by a normocytic normochromic anemia with severe reticulocytopenia and marked reduction or absence of erythroid precursors from the bone marrow. Diamond-Blackfan anemia is a congenital form of PRCA. Acquired PRCA may be either a primary disorder or secondary to some other disorder or agent. Primary acquired PRCA is an autoimmune disorder that is frequently antibody-mediated. Myelodysplastic syndromes may also present with the morphologic appearance of PRCA. Secondary acquired PRCA may be associated with collagen vascular/autoimmune disorders such as systemic lupus erythematosus; lymphoproliferative disorders such as chronic lymphocytic leukemia or large granular lymphocyte leukemia; infections, particularly B19 parvovirus; thymoma and other solid tumors; or a variety of other disorders, drugs, or toxic agents. The therapeutic approach to PRCA typically involves immunosuppression, but specific pathogenic subtypes are associated with specific therapeutic approaches. Cyclosporine A, with or without concurrent corticosteroids, appears to be the single most effective immunosuppressive agent.

Th17-related cytokines in systemic lupus erythematosus patients with dilated cardiomyopathies: a possible linkage to parvovirus B19 infection.

Dilated cardiomyopathies (DCM) are a major cause of mortality in patients with systemic lupus erythematosus (SLE). Immune responses induced by human parvovirus B19 (B19) are considered an important pathogenic mechanism in myocarditis or DCM. However, little is known about Th17-related cytokines in SLE patients with DCM about the linkage with B19 infection. IgM and IgG against B19 viral protein, and serum levels of Th17-related cytokines were determined using ELISA in eight SLE patients with DCM and six patients with valvular heart disease (VHD). Humoral responses of anti-B19-VP1u and anti-B19-NS1 antibody were assessed using Western blot and B19 DNA was detected by nested Polymerase Chain Reaction (PCR). Levels of interleukin (IL)-17, IL-6, IL-1ß, and tumor necrosis factor (TNF)-α were significantly higher in SLE patients with DCM (mean ± SEM, 390.99±125.48 pg/ml, 370.24±114.09 pg/ml, 36.01±16.90 pg/ml, and 183.84±82.94 pg/ml, respectively) compared to healthy controls (51.32±3.04 pg/ml, p<0.001; 36.88±6.64 pg/ml, p<0.001; 5.39±0.62 pg/ml, p<0.005; and 82.13±2.42 pg/ml, p<0.005, respectively). Levels of IL-17 and IL-6 were higher in SLE patients with DCM versus those with VHD (both p<0.01). Five (62.5%) of DCM patients had detectable anti-B19-NS1 IgG and four (50.0%) of them had anti-B19-VP1u IgG, whereas only one (16.7%) of VHD patients had detectable anti-B19-NS1 IgG and anti-B19-VP1u IgG. Serum levels of IL-17, IL-6 and IL-1ß were markedly higher in SLE patients with anti-B19-VP1u IgG and anti-B19-NS1 IgG compared to those without anti-B19-VP1u IgG or anti-B19-NS1 IgG, respectively. These suggest a potential association of B19 with DCM and Th17-related cytokines implicated in the pathogenesis of DCM in SLE patients.

Infection and immunity for human parvovirus B19 in patients with febrile exanthema.

The contribution of parvovirus B19 (B19V) as a causative agent of febrile exanthema (FE) in Cordoba, Argentina, was analysed by detection of viral DNA, and specific IgM and IgG. Serum from 141 patients with FE who were negative for measles and rubella, collected during 2005-2009, plus serum from 31 healthy individuals, were assayed. B19V was the aetiological agent in 14·9% of all FE cases, and in 39·1% in an epidemic year (2007). B19V DNA was detected in 47·6% of IgM-positive FE patients, 30·2% of IgM-negative/IgG-positive FE patients, and 9·7% of healthy controls, indicating B19V long-term infection in ~10% of immunocompetent individuals. Persistent B19V DNA was significantly more frequent in children than adults and in males than females. All patients with acute B19V infection had rash and fever, 85·7% had adenopathy, and only 14·3% had arthropathy. This is the first follow-up study of markers of infection and immunity for B19V infection in Argentina.

[The diagnostic value of virus serology in patients with non-ischemic systolic heart failure and parvovirus B19 infection]. / Wartosc diagnostyczna testów serologicznych u chorych ze skurczowa nie-niedokrwienna niewydolnoscia serca i zakazeniem parwowirusem B19.

INTRODUCTION: We determined retrospective analysis of the diagnostic value of virus serology in patients with non-ischemic systolic heart failure and parvovirus B19 infection. MATERIAL AND METHODS: Virus serology and endomyocardial biopsy were performed in 31 patients with non-ischemic systolic heart failure hospitalized from 2001 to 2006 in our clinic. RESULTS: The serum specimens from 31 patients were tested for IgM and IgG antibody against parvovirus B19. IgM antibodies were identified in 3 patients and IgG antibodies were identified in 23 patients. All of the patients underwent endomyocardial biopsy which revealed chronic active myocarditis in 10 patients (32.4%), chronic persistent myocarditis in 14 patients (45.1%) and no myocarditis in 7 patients (22.5%). CONCLUSIONS: Virus serology has no relevance for the diagnosis of non-ischemic systolic heart failure caused by parvovirus B19 infection. The result of serological tests are positive more frequently than the biopsy specimens results.

Relevance of specific immunoglobulin M and immunoglobulin G for parvovirus B19 diagnosis in patients with acute lymphoblastic leukemia receiving chemotherapy: prospective study.

CONTEXT: Immunocompromised patients suffer from prolonged viral infections often without detectable immune response. However, even if the immune response occurs, can it clear the virus completely? OBJECTIVE: To detect parvovirus B19 DNA and its antibodies in bone marrow cells and in serum by polymerase chain reaction (PCR) in children with acute lymphoblastic leukemia receiving chemotherapy to highlight the relation of humoral immune response to the presence of viremia. Also, to evaluate the optimal diagnostic test(s) for a correct diagnosis of parvovirus B19 disease in immunocompromised patients. DESIGN: Forty-eight children with acute lymphoblastic leukemia receiving maintenance chemotherapy were included in the study in addition to 20 healthy children with matched age and sex. Study for parvovirus B19 was performed by serologic determination of specific immunoglobulin (Ig) M and IgG, and viral DNA was determined by PCR in both serum and bone marrow aspiration. RESULTS: Parvovirus B19 DNA was detected in both serum and bone marrow in 20% of patients. Specific IgG was found in 40% and IgM in 26.7%. Two cases (10%) in the control group were positive for IgG. The agreement between IgG and positive results of PCR in the bone marrow was 33.3%, and the agreement for IgM and PCR in the serum was 33.3%. CONCLUSIONS: Parvovirus B19 is considered a common viral infection in children with acute lymphoblastic leukemia receiving chemotherapy. We must use our full potential to exclude such infection, which can mimic the side effects of chemotherapy in these patients. In immunocompromised patients, there are immunologic discrepancies in humoral immune responses for both IgM and IgG between individuals with parvovirus B19 persistence and healthy individuals, findings that may reflect both failed immunity and antigenic exhaustion. The contemporaneous determination of parvovirus B19 DNA by PCR in both bone marrow and peripheral blood and specific serologic markers appears to be the most appropriate diagnostic protocol for the correct laboratory diagnosis of parvovirus B19 infection in these patients.

Acute renal failure in a pediatric kidney allograft recipient treated with intravenous immunoglobulin for parvovirus B19 induced pure red cell aplasia.

Infection with parvovirus B19 (PV-B19) after solid organ transplantation may cause pure red cell aplasia (PRCA). Intravenous immunoglobulin (IVIg) may be of benefit in clearing the infection. Acute renal failure is a known adverse effect of IVIg administration. A 14-yr-old male received a cadaveric renal transplant. Three weeks after surgery he developed symptomatic anemia (hemoglobin 4.5 g/dL, reticulocyte count 0.2%). Anti-PV-B19 IgM and IgG titers, which had been negative pretransplant, were positive. He received two IVIg infusions as treatment for the PV-B19 infection. Four days after the IVIg infusions he developed non-oliguric acute renal failure (ARF) with a rise in serum creatinine from 1 to 1.8 mg/dL. Allograft biopsy showed changes consistent with an osmotic load. Anemia and the renal failure resolved after transfusions and IVIg. PV-B19 infection in immunosuppressed transplant recipients is associated with significant morbidity and may respond to IVIg therapy. High sucrose IVIg preparations may be associated with renal failure in renal allograft recipients. Adding PV-B19 testing of the donor and recipient to the standard pretransplant evaluation may be beneficial in diagnosing and managing a potential infection. If IVIg is to be used it may be safer to use a sucrose-free IVIg preparation.

Prolonged activation of virus-specific CD8+T cells after acute B19 infection.

BACKGROUND: Human parvovirus B19 (B19) is a ubiquitous and clinically significant pathogen, causing erythema infectiosum, arthropathy, transient aplastic crisis, and intrauterine fetal death. The phenotype of CD8+ T cells in acute B19 infection has not been studied previously. METHODS AND FINDINGS: The number and phenotype of B19-specific CD8+ T cell responses during and after acute adult infection was studied using HLA-peptide multimeric complexes. Surprisingly, these responses increased in magnitude over the first year post-infection despite resolution of clinical symptoms and control of viraemia, with T cell populations specific for individual epitopes comprising up to 4% of CD8+ T cells. B19-specific T cells developed and maintained an activated CD38+ phenotype, with strong expression of perforin and CD57 and downregulation of CD28 and CD27. These cells possessed strong effector function and intact proliferative capacity. Individuals tested many years after infection exhibited lower frequencies of B19-specific cytotoxic T lymphocytes, typically 0.05%-0.5% of CD8+ T cells, which were perforin, CD38, and CCR7 low. CONCLUSION: This is the first example to our knowledge of an "acute" human viral infection inducing a persistent activated CD8+ T cell response. The likely explanation--analogous to that for cytomegalovirus infection--is that this persistent response is due to low-level antigen exposure. CD8+ T cells may contribute to the long-term control of this significant pathogen and should be considered during vaccine development.

Epidemiology of human parvovirus B19 in children with sickle cell disease.

Human parvovirus (HPV) B19 causes significant morbidity and mortality in children with sickle cell disease (SCD), but little data are published about the epidemiology of HPV B19 infection and its associated complications in this patient population. In this study, prevalence and incidence rates of HPV B19 were determined in 633 patients with SCD followed at The Children's Hospital of Philadelphia between November 1996 and December 2001. Thirty percent (30%) were HPV B19 immunoglobulin G (IgG) positive at first testing, and the 70% without evidence of past HPV B19 infection were tested annually. One hundred ten patients developed evidence of HPV B19 infection for an incidence rate of 11.3 per 100 patient years. Sixty-eight episodes of HPV B19-induced transient red cell aplasia occurred with the following clinical events: fever (89.7%), pain (61.8%), acute splenic sequestration (19.1%), and acute chest syndrome (11.8%). Pain, fever, and acute splenic sequestration were more frequent events with acute HPV B19 infections compared with acute events in uninfected patients. The results of this epidemiologic study, the largest and most comprehensive to date, justify the development of HPV B19 prevention strategies to diminish the frequent and often severe complications associated with HPV B19 infections in patients with SCD.

[The use of real-time polymerase chain reaction and enzyme immunoassay for the diagnosis of acute parvovirus B19 infections in immunosuppressed patients]. / Immünsüpresif hastalarda akut parvovirus B19 enfeksiyonunun tanisinda enzim immún yóntemi ile gerçek zamanli polimeraz zincir reaksiyonunun kullanimi.

Human parvovirus B19 (PV-B19) infection may lead to very serious clinical situations such as transient aplastic crisis in patients with hemolytic anemia, thrombocytopenia, neutropenia and transient arthritis accompanied with erythema infectiosum, especially in immunosuppressed patients. Early diagnosis of PV-B19 infection is of critical importance especially in immunosuppressed patients since the necessary precautions can be undertaken accordingly. In this study, PV-B19 IgM and IgG antibodies and viral DNA have been searched by enzyme immunoassay (ELISA) and real-time polymerase chain reaction (PCR), respectively, in 50 PV-B19 suspected immunosuppressed patients. Viral IgM, IgG and DNA positivities were detected in 7 (14%), 20 (40%) and 7 (14%) of the patients, respectively. During the first week three patients were found DNA and IgM positive but IgG negative, while four patients were found positive for the viral DNA, IgM and IgGs. The DNA copy numbers were high in all of the patients during the first week, with a gradual decrease during a seven-week follow-up period. IgM antibodies have disappeared in the sixth week in three of the patients and at the end of the seventh week in four of the patients. Although the IgG antibodies were negative in three patients in the first week, they became positive in the second week and the titers gradually increased during the following weeks. According to the results of this study, it can be concluded that, in high risk groups such as immunosuppressed patients, in addition to ELISA, real-time PCR method would be helpful for the early diagnosis of PV-B19 infections.

Parvovirus B19 infection in pediatric solid-organ and bone marrow transplantation.

The clinical significance of parvovirus B19 infection in pediatric solid-organ and bone marrow transplanted patients is unclear. The overall prevalence of parvovirus B19 infection in these patients is about 1-2% during the first year after transplantation. The most common symptom is anemia, but leukopenia and thrombocytopenia have also been observed. Rare cases of hepatic dysfunction, myocarditis, vasculitis and respiratory failure have also been reported. Whereas serology is of limited value around the time of transplantation, it is recommended that a search for B19 DNA is included in first-line investigations in any transplanted patient with unexplained anemia. Specific antiviral therapy is not available, however, intravenous immunoglobulin produces rapid improvement in most cases. Although relatively rare, the severe complications following parvovirus B19 infection in the transplant setting can be avoided by early diagnosis and treatment.

Anti-VP1 and anti-VP2 antibodies detected by immunofluorescence assays in patients with acute human parvovirus B19 infection

Acute human parvovirus B19 infection is followed by an antibody response to the structural proteins of the viral capsid (VP1 and VP2). We used 80 sera collected from 58 erythema infectiosum and 6 transient aplastic crisis patients to test IgM and IgG antibodies against these two proteins in an immunofluorescence assay (IFA) using Sf9 cells infected with recombinant baculovirus expressing either VP1 or VP2 antigen. Although less sensitive than IgM capture enzyme immunoassay using native antigen (MACEIA), we could detect anti-VP1 or anti-VP2 IgM antibodies by IFA in 49 patients with acute infection (76.6 percent). Detection of IgG anti-VP1 and anti-VP2 by IFA, however, was as sensitive as IgG detection by indirect enzyme immunoassay. By applying IgG avidity IFA to sera of the 15 IgM IFA negative patients we were able to confirm acute infection in further 12 cases by IFA. Overall, acute infection was confirmed by IFA in 61 (95.3 percent) of the 64 patients