Encephalopathy Caused by Human Parvovirus B19 Genotype 1 Associated with Haemophilus influenzae Meningitis in a Newborn.

Parvovirus B19 infection is associated with a wide range of clinical manifestations, from asymptomatic to severe neurological disorders. Its major clinical symptoms, fever and rash, are common to multiple viruses, and laboratory tests to detect B19 are frequently not available. Thus, the impact of B19 on public health remains unclear. We report the case of a 38-day old girl admitted to São Paulo Clinical Hospital, Brazil, with an initial diagnosis of bacterial meningitis, seizures, and acute hydrocephalus. Antibiotic therapy was maintained for one week after admission and discontinued after negative laboratory results were obtained. Nine days after symptoms onset, a cerebral spinal fluid (CSF) sample revealed persistent pleocytosis. The complete B19 complete genome was subsequently identified in her CSF by a metagenomic next-generation sequencing approach. This report highlights the possible involvement of B19 in the occurrence of acute neurological manifestations and emphasizes that its possible involvement might be better revealed by the use of metagenomic technology to detect viral agents in clinical situations of unknown or uncertain etiology.

Hiperplasia eritroblástica secundaria a infección aguda por parvovirus B19

Resumen La infección aguda por parvovirus B19 es una enfermedad autolimitada en pacientes sin trastornos inmunitarios. Sin embargo, en pacientes con discrasias sanguíneas pueden manifestarse con una crisis aplásica. Presentamos el caso de un varón de 48 años, con una esferocitosis hereditaria no diagnosticada previamente, la cual debutó con una crisis aplásica inducida por una infección aguda de parvovirus B19. La sospecha clínica se planteó luego del análisis histopatológico de la médula ósea, en el que se observó una hiperplasia eritroblástica, con precursores eritroides gigantes e inclusiones nucleares virales, y cuyo análisis inmunohistoquímico fue positivo para la proteína de la cápside viral VP1 y VP2 de parvovirus B19 en células infectadas. Se confirmó la sospecha diagnóstica con la detección de anticuerpos IgM de parvovirus B19. De acuerdo a nuestra revisión, este es el primer reporte de un adulto en Latinoamérica que debutó con una crisis aplásica inducida por una infección aguda por parvovirus B19, como primera manifestación de una esferocitosis hereditaria.

Abstract Acute parvovirus B19 infection is a self-limiting disease in patients with normal immune response. However, in patients with blood dyscrasias, it is possible to present with an aplastic crisis. We present the case of a 48-year-old man who had developed an aplastic crisis as a result of an acute parvovirus B19 infection with an undiagnosed hereditary spherocytosis. Suspicions of the parvovirus infection began to arise after a routine bone marrow histopathological analysis which showed erythroblastic hyperplasia with giant erythroid precursor and viral inclusions. A subsequent immunohistochemical analysis tested positive for VP1 and VP2 capsid proteins of parvovirus B19 in infected cells. The diagnostic suspicion was later confirmed with the presence of anti-parvovirus B19 IgM. According to our review, this is the first published case in Latin America that documents an adult patient with normal immune response whose first symptom of hereditary spherocytosis was an aplastic crisis induced by an acute parvovirus B19 infection.

Viral metagenomics performed in patients with acute febrile syndrome during Toxoplasma gondii outbreak in south Brazil

ABSTRACT Toxoplasmosis is a zoonotic infection caused by the protozoan parasite Toxoplasma gondii. The infection is widely disseminated in the human population and is usually benign or asymptomatic. Systemic T. gondii infection presents risks for pregnant women and AIDS patients. Although rare, T. gondii can cause outbreaks in urban centers. The origin of these outbreaks is not completely understood but probably results from introduction of zoonotic T. gondii strains in the population. During such outbreaks other pathogens which mimic T. gondii acute febrile syndrome may also circulate; therefore, detailed investigation of the outbreak is of extreme importance. In this study we performed viral metagenomics next-generation sequencing (mNGS) in patient samples obtained during T. gondii outbreak in Santa Maria city, South Brazil. Specific bioinformatics pipelines specialized in virus discovery were applied in order to identify co-circulating vial agents. Epstein Barr virus and Parvovirus B19 contigs were assembled and these viruses can cause symptoms similar to toxoplasmosis. In conclusion, our findings show the importance of Metagenomics next generation sequencing (mNGS) use to help characterize the outbreak more completely and in the management of the affected patients.

Viral metagenomics performed in patients with acute febrile syndrome during Toxoplasma gondii outbreak in south Brazil.

Toxoplasmosis is a zoonotic infection caused by the protozoan parasite Toxoplasma gondii. The infection is widely disseminated in the human population and is usually benign or asymptomatic. Systemic T. gondii infection presents risks for pregnant women and AIDS patients. Although rare, T. gondii can cause outbreaks in urban centers. The origin of these outbreaks is not completely understood but probably results from introduction of zoonotic T. gondii strains in the population. During such outbreaks other pathogens which mimic T. gondii acute febrile syndrome may also circulate; therefore, detailed investigation of the outbreak is of extreme importance. In this study we performed viral metagenomics next-generation sequencing (mNGS) in patient samples obtained during T. gondii outbreak in Santa Maria city, South Brazil. Specific bioinformatics pipelines specialized in virus discovery were applied in order to identify co-circulating vial agents. Epstein Barr virus and Parvovirus B19 contigs were assembled and these viruses can cause symptoms similar to toxoplasmosis. In conclusion, our findings show the importance of Metagenomics next generation sequencing (mNGS) use to help characterize the outbreak more completely and in the management of the affected patients.

TREATMENT STRATEGIES AND OUTCOME OF PARVOVIRUS B19 INFECTION IN KIDNEY TRANSPLANT RECIPIENTS: A CASE SERIES AND LITERATURE REVIEW OF 128 PATIENTS.

BACKGROUND: There is no specific antiviral treatment for parvovirus B19 (PVB19) infection. OBJECTIVE: The objective of this study was to study the treatment and outcome of PVB19 infection in kidney transplant recipients (KTR) at our institution, and cases published in the medical literature. METHODS: We conducted a retrospective review of PVB19 infection in KTR at an academic medical center over a 16-year period and summarized the data on its treatment and outcome in 120 KTR in the medical literature. RESULTS: In our cohort of eight patients, the median time to the onset of PVB19 disease was 7.2 weeks after transplantation. All patients had severe aregenerative anemia (mean hemoglobin (Hb) of 6.2 ± 1.0 g/dl); all were treated with a reduction in their immunosuppressive regimen and the administration of single-dose intravenous immunoglobulin (IVIG) (mean total dosage of 0.87 ± 0.38 g/kg). The median time to anemia improvement (Hb >10 g/dl) was 3-week post-treatment. No recurrences were documented during follow-up (median 25 months). Among 128 patients (including our cohort of 8 and 120 reported in literature), therapeutic strategies included: 43% IVIG alone, 39% IVIG and reduced immunosuppression, 9% reduction of immunosuppression, and 9% conservative therapy. Clinical relapses were observed in 35% of 71 reported cases. CONCLUSIONS: In KTR, decreasing immunosuppression and the administration of low-dose immunoglobulin seem to be not worse than the standard dose in PVB19 infection.

Treatment strategies and outcome of parvovirus b19 infection in kidney transplant recipients: a case series and literature review of 128 patients.

Abstract Background There is no specific antiviral treatment for parvovirus B19 (PVB19) infection. Objective The objective of this study was to study the treatment and outcome of PVB19 infection in kidney transplant recipients (KTR) at our institution, and cases published in the medical literature. Methods We conducted a retrospective review of PVB19 infection in KTR at an academic medical center over a 16-year period and summarized the data on its treatment and outcome in 120 KTR in the medical literature. Results In our cohort of eight patients, the median time to the onset of PVB19 disease was 7.2 weeks after transplantation. All patients had severe aregenerative anemia (mean hemoglobin (Hb) of 6.2 ± 1.0 g/dl); all were treated with a reduction in their immunosuppressive regimen and the administration of single-dose intravenous immunoglobulin (IVIG) (mean total dosage of 0.87 ± 0.38 g/kg). The median time to anemia improvement (Hb >10 g/dl) was 3-week post-treatment. No recurrences were documented during follow-up (median 25 months). Among 128 patients (including our cohort of 8 and 120 reported in literature), therapeutic strategies included: 43% IVIG alone, 39% IVIG and reduced immunosuppression, 9% reduction of immunosuppression, and 9% conservative therapy. Clinical relapses were observed in 35% of 71 reported cases. Conclusions In KTR, decreasing immunosuppression and the administration of low-dose immunoglobulin seem to be not worse than the standard dose in PVB19 infection.

Identification of human parvovirus B19 among measles and rubella suspected patients from Cuba.

Between September 2014 and December 2015, 298 sera from rash and fever patients from all over Cuba were investigated for specific IgM antibodies against measles, rubella, dengue, human parvovirus B19 (B19V) and human herpesvirus 6 (HHV6) using a commercial enzyme-linked immunosorbent assay kits. B19V IgM positive and equivocal samples were investigated by a polymerase chain reaction and genotyping. No measles, rubella or dengue cases were detected. HHV6-IgM antibodies were confirmed in 5.7% and B19V-IgM antibodies in 10.7% of the patients. A total of 31.3% of the B19V cases were between 5 and 9 years old and 34.4% were 20 years and older. The only B19V sequence obtained belonged to genotype 1a. Diagnosis was established for only 16% of the rash and fever patients, suggesting that other diseases such as Zika or Chikungunya may play a role.

Quantitative real-time PCR for differential diagnostics of parvovirus B19 infection in acute liver failure patients.

BACKGROUND: Human Parvovirus B19 (B19V) is a common pathogen worldwide. After primary infection, B19V-DNA may permanently persist in non-erythroid tissues, including the liver of patients with acute liver failure (ALF). OBJECTIVE: To validate a real-time PCR (qPCR) for the quantification of B19V-DNA, in order to establish a differential diagnosis for B19V infection in ALF patients. METHODS: The qPCR techniques were based on Sybr Green® and TaqMan® methodologies. To evaluate the quality parameters of both methods, samples from patients with or without B19V infection were tested. The diagnostic utility of qPCR in the detection B19V-DNA in patients with ALF was evaluated by testing archived serum and hepatic tissue explants from 10 patients. RESULTS: The Sybr Green® methodology showed 97% efficiency, the limits of detection and quantification were 62.6 and 53,200 copies/mL, respectively. The TaqMan® methodology showed 95% efficiency, the limits of detection and quantification were 4.48 and 310 copies/mL, respectively. A false positive result was found only with the Sybr Green® methodology. Among ALF patients without defined etiology, three (30%) were positive for B19V DNA in serum and liver. CONCLUSION: The qPCR methods validated here were effective in clarifying uncommon cases of B19V-related ALF and are fit for differential diagnosis of ALF causes.

Human parvovirus B19 genotype 1 in suspected dengue patients of Tefé, Amazonas State, Brazil

Abstract INTRODUCTION: Human parvovirus B19 (B19V) is a common pathogen, which on infection causes variety of clinical conditions from benign self-limiting exanthematous disease and other similar pathologies to fetal death. METHODS: We collected 341 serum samples between the first and fourth day after the onset of symptoms from all patients suspected of dengue fever who were attended at Regional Hospital of Tefé. Initially, patients were screened for malaria by blood smear test and negative samples were sent to Fundação de Medicina Tropical Doutor Heitor Vieira Dourado (FMT-HVD) situated in Manaus (AM) for dengue testing using semi-nested multiplex PCR. Further, we investigated 44 malaria and dengue-negative samples of children for B19V DNA by nested-PCR. Positive samples were analyzed by BLAST against entire public non-redundant nucleotide database and genotyped by phylogenetic analyses using neighbor-joining clustering method. RESULTS: Eight samples (18.2%) were found to be PCR positive. Fever, headache, ocular pain, and/or muscle pain were reported as the most frequent symptoms by the patients and none were diagnosed with rash at the time of sample collection. Phylogenetic analysis of major capsid protein 2 (VP2) and VP3 coding region showed high similarity with B19V genotype 1. CONCLUSIONS: Our results reveal the spread of B19V genotype 1 in Tefé. Moreover, our results emphasize the significance of laboratorial differential diagnosis using molecular techniques in patients with acute febrile, and thereby aid the health surveillance system in improving patient care even in the remote areas of Amazon.

Serological and molecular evaluation of parvovirus B19 (B19V) in blood donors from the Blood Center of Brasília, Brazil: focus on women of childbearing age / Avaliação sorológica e molecular do parvovírus B19 (B19V) em doadores de sangue da Fundação Hemocentro de Brasília, Brasil: foco em mulheres em idade fértil

ABSTRACT Parvovirus B19 (B19V) can be transmitted by the respiratory route, vertically - from the mother to the fetus - and via blood transfusion or organ transplantation. Infection by transfusion of blood or blood products occurs due to the resistance of B19V to viral inactivation methods. Our study evaluated the presence of B19V deoxyribonucleic acid (DNA) and the prevalence of anti-B19V class G immunoglobulin (IgG) in women of childbearing age blood donors of the Federal District, Brazil. Our results demonstrated the absence of B19V DNA in these blood donors. However, the seroprevalence for anti-B19V IgG was observed in 60.7% of this population. This study provides important data of B19V circulation in the Center-West of Brazil.

RESUMO O parvovírus B19 (B19V) pode ser transmitido por via respiratória, verticalmente - da mãe para o feto - e via transfusão de sangue e transplante de órgãos. A infecção por transfusão de sangue ou hemoderivados ocorre devido à resistência do B19V aos métodos de inativação viral. Nosso estudo avaliou a presença do ácido desoxirribonucleico (DNA) B19V e a prevalência de imunoglobulina da classe G (IgG) anti-B19V em mulheres em idade fértil, doadoras de sangue do Distrito Federal, Brasil. Nossos resultados demonstraram a ausência de DNA de B19V nesses doadores. No entanto, foi observada a soroprevalência de IgG anti-B19V em 60,7% dessa população. Este estudo fornece dados importantes da circulação do B19V no Centro-Oeste do Brasil.

Aplasia pura de células rojas secundaria a infección por parvovirus B19 en paciente VIH positivo / Pure red cell aplasia secondary to parvovirus B19 infection in an HIV positive patient

Resumen La infección crónica por parvovirus B19 en pacientes seropositivos para el virus de inmunodeficiencia humana (VIH) es una causa identificable y tratable de anemia en esta población, que en nuestro medio aún no ha sido muy estudiada. La búsqueda activa de este patógeno en pacientes VIH positivos con anemia grave sin compromiso de otras líneas celulares puede llevar a una mejoría en la calidad de vida en el tiempo y reducción de los costos de la enfermedad para el sistema de salud. Nosotros presentamos el caso de un paciente con síndrome de inmunodeficiencia adquirida y anemia a quien se le identifico parvovirus B19. (Acta Med Colomb 2018; 43: 42-44).

Abstract The chronic infection by parvovirus B19 in seropositive patients for the human immunodeficiency virus (HIV) is an identifiable and treatable cause of anemia in this population, which in our environment has not yet been widely studied. The active search for this pathogen in HIV positive patients with severe anemia without compromising other cell lines can lead to an improvement in the quality of life over time and reduction of the costs of the disease to the health system. We present the case of a patient with acquired immunodeficiency syndrome and anemia who was identified as parvovirus B19. (Acta Med Colomb 2018; 43: 42-44).

Genotype 1 of human parvovirus B19 in clinical cases / Genótipo 1 do parvovírus humano em casos clínicos

Summary Introduction: Virus surveillance strategies and genetic characterization of human parvovirus B19 (B19V) are important tools for regional and global control of viral outbreak. In São Paulo, Brazil, we performed a study of B19V by monitoring the spread of this virus, which is an infectious agent and could be mistakenly reported as a rash and other types of infection. Method: Serum samples were subjected to enzyme immunoassay, real time polymerase chain reaction, and sequencing. Results: From the 462 patients with suspected cases of exanthematic infections, the results of the 164 serum samples were positive for B19V immunoglobulin M. Among these cases, there were 38 patients with erythema infections and B19-associated with other infections such as encephalitis, hydrops fetalis, chronic anemia, hematological malignancies. These samples were sequenced and identified as genotype 1. Conclusion: This study showed patients with infections caused by B19V and sequencing genotype 1. Continuous monitoring is necessary to detect all known genotypes, and the emergence of new genotypes of these viruses for case management in public health control activities.

Resumo Introdução: Estratégias de vigilância para o parvovírus humano B19 e caracterização genética são ferramentas importantes para o controle regional e global do surto viral. Em São Paulo, Brasil, foi realizado um estudo de parvovírus B19, monitorando a disseminação desse vírus, que é um agente infeccioso e poderia ser erroneamente relatado como uma erupção cutânea e outros tipos de infecções. Método: As amostras de soro foram submetidas ao ensaio imunoenzimático, PCR quantitativo em tempo real e sequenciamento. Resultados: Dos 462 pacientes com casos suspeitos de infecções exantemáticas, os resultados das 164 amostras de soro foram positivos para parvovírus B19 imunoglobulina M. Entre eles, 38 pacientes com eritema infeccioso apresentaram B19 associado com outras infecções, como encefalite, hidropisia fetal, anemia crônica, doenças hematológicas malignas. Essas amostras foram sequenciadas e identificadas como genótipo 1. Conclusão: Os pacientes foram infectados com parvovírus B19 e apresentaram genótipo 1. Monitoração contínua é necessária para detectar todos os genótipos conhecidos e o surgimento de novos genótipos para o controle de casos em saúde pública.

Prevalence and Viral Load of Human Parvovirus B19 (B19V) Among Blood Donors in South-East Brazil.

The infection of human parvovirus B19 (B19V) is a common event in the general population, including volunteer blood donors. In some cases it can be asymptomatic and can remain persistent for a long period of time. The objective of this study was to examine the B19V DNA prevalence and viral load in first-time volunteer blood donors. Blood samples were collected from 91 primary blood donors at the Regional Blood Center of Ribeirão Preto, Southeast Brazil. Viral detection and quantitation was performed by an in-house TaqMan(®) real-time PCR with high sensitivity. B19V DNA was detected in one male blood donor (1.0 %) and was characterized by a very low viral load (537.36 copies/mL). Our studies demonstrate that B19V DNA at low titer may be present in apparently healthy individuals. Sensitive molecular diagnostic tools can be applied for the screening of fresh blood derived products in order to prevent transfusion-transmitted B19V infection.

Clinical features and laboratory findings of human parvovirus B19 in human immunodeficiency virus-infected patients

Immunocompromised patients may develop severe chronic anaemia when infected by human parvovirus B19 (B19V). However, this is not the case in human immunodeficiency virus (HIV)-infected patients with good adherence to highly active antiretroviral treatment (HAART). In this study, we investigated the clinical evolution of five HIV-infected patients receiving HAART who had B19V infections confirmed by serum polymerase chain reaction. Four of the patients were infected with genotype 1a strains and the remaining patient was infected with a genotype 3b strain. Anaemia was detected in three of the patients, but all patients recovered without requiring immunoglobulin and/or blood transfusions. In all cases, the attending physicians did not suspect the B19V infections. There was no apparent relationship between the infecting genotype and the clinical course. In the HAART era, B19V infections in HIV-positive patients may be limited, subtle or unapparent.

Frequencia de anticorpos antiparvovirus B19 em artrite reumatoide e lupus eritematoso sistemico / Frequency of antiparvovirus B19 antibodies in rheumatoid arthritis and systemic lupus erythematosus

Objetivo: Determinar a frequência de anticorpos antiparvovírus B19 (B19) em pacientes com artrite reumatoide (AR) e lúpus eritematoso sistêmico (LES), e a possível correlação da soropositividade anti-B19 com a atividade das doenças e a qualidade de vida. Pacientes e métodos: Foram utilizadas amostras séricas de 57 pacientes com AR, 45 com LES e 65 controles sadios. Empregou-se protocolo com dados clínicos, os índices Disease Activity Score 28 (DAS 28), Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) e Health Assessment Questionnaire (HAQ). Realizou-se a sorologia anti-B19 por ensaio imunoenzimático (ELISA). Resultados: A média de idade dos pacientes foi de 42,74 14,09 anos, e a dos controles foi de 38,38 13,42 anos.Tinham doença ativa 79 (77,5%) pacientes, e doença inativa 23 (22,5%).Anti-B19 (IgG) foi reagente em 49 (86,0%) IC 95% (77,0 - 95,0)% pacientes com AR, em 38 (84,4%) IC 95% (73,9 - 95,0)% com LES e em 40 (61,5%) IC 95% (49,7 - 73,4)% controles (p = 0,002). Anti-B19 (IgM) foi reagente em 3 (5,3%) IC 95% (0,0 - 11,1)% pacientes com AR, em 7 (15,6%) IC 95% (5,0 - 26,2)% pacientes com LES e em 1 (1,5%) IC 95% (0,0 - 4,5)% controle (p = 0,011). Não houve correlação da reatividade anti-B19 com a atividade das doenças, os índices DAS 28, SLEDAI e HAQ. Conclusão: O presente estudo demonstrou que a população avaliada está exposta à infecção pelo B19, o que demanda atenção com suas manifestações, principalmente entre os pacientes que apresentam maior risco, como os imunossuprimidos. .

Objective: To determine the frequency of antiparvovírus B19 (B19) antibodies in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), and the possible correlation of anti-B19 seropositivity with disease activity and quality of life. Patients and methods: Serum samples from 57 patients with RA, 45 with SLE and 65 healthy controls were used. We applied protocol with clinical data, and the Disease Activity Score 28 (DAS 28), Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) and Health Assessment Questionnaire (HAQ) indexes. The anti-B19 serology was done by enzyme-linked immunosorbent assay (ELISA). Results: The mean age of patients was 42.74 ± 14.09 years, and of controls was 38.38 ± 13.42 years. 79 patients had active disease (77.5%), and 23 had inactive disease (22.5%). Anti-B19 (IgG) was positive in 49 (86.0%; CI 95% 77.0 - 95.0) RA patients, 38 (84.4%; CI 95% 73.9 - 95.0) SLE patients, and 40 (61.5%; CI 95% 49.7 - 73.4) controls (p = 0.002). Anti-B19 (IgM) was positive in 3 (5.3%; CI 95% 0.0 - 11.1) RA patients, in 7 (15.6%; CI 95% 5.0 - 26,2) SLE patients, and in 1 (1.5%; CI 95% 0.0 - 4.5) control (p = 0.011).There was no correlation of anti-B19 reactivity with disease activity and with DAS 28, HAQ and SLEDAI indexes. Conclusion: This study demonstrated that the studied population is exposed to infection by B19, which demands attention with its manifestations, especially among patients at greatest risk, such as those immunosuppressed. .

Molecular and clinical evaluation of the acute human parvovirus B19 infection: comparison of two cases in children with sickle cell disease and discussion of the literature

Human parvovirus B19 is a well-known cause of severe conditions in patients with sickle cell disease, but the molecular mechanisms of the infection are insufficiently understood. The different clinical outcome of the acute parvovirus B19 infection in two pediatric patients with sickle cell disease has been examined. One of them developed life-threatening condition requiring emergency transfusions, while the other had asymptomatic infection, diagnosed occasionally. Both cases had high viral load and identical subgenotype, indicating that the viral molecular characteristics play a minimal role in the infection outcome.

Case for diagnosis / Caso para diagnóstico

Papular-purpuric gloves and socks syndrome is a rare, highly contagious dermatosis caused by parvovirus B19, which may result in the abrupt cessation of red blood cell production in patients with preexisting hematological diseases. It affects predominantly children and young adults and has an unusual presentation.

A síndrome "gloves and socks" pápulo-purpúrica é uma dermatose incomum, altamente contagiosa, causada pelo parvovírus B19, que pode provocar interrupção aguda da produção de glóbulos vermelhos em pacientes com doenças hematológicas preexistentes. Acomete, principalmente, crianças e jovens, e tem uma apresentaçao nao-usual.

Parvovirus B19 seroconversion in a cohort of human immunodeficiency virus-infected patients

Erythrovirus B19 (B19V) infection may cause red cell aplasia in patients infected with human immunodeficiency virus (HIV). The introduction of highly active antiretroviral therapy (HAART) has improved the immune function of these patients by modifying the course of B19V infection. The purpose of this study was to estimate the frequency of B19 seroconversion in a cohort of HIV-infected patients and evaluate the occurrence of B19V-related anaemia during the seroconversion period. Adult HIV-infected patients were studied at a public hospital in Niterói, state of Rio de Janeiro, Brazil. IgG and IgM antibodies against B19V were detected by an enzyme-linked immunosorbent assay and B19 viraemia was assayed by polymerase chain reaction. Medical records were reviewed for any clinical evaluation of anaemia. Seroconversion was detected in 31.8% of the 88 individuals who began the study as anti-B19V IgG-negative. No clinical manifestations of B19V infection were detected during the period of seroconversion. Patients who seroconverted were 5.40 times more likely to have anaemia than those who did not [odds ratio 5.40 (95% confidence interval: 1.33-22.93)]. Anaemia was detected in eight patients. All patients recovered from anaemia by either beginning or continuing HAART, without requiring blood transfusions. In the HAART era, B19V infection may only be associated with a course of disease characterised by less severe chronic anaemia. This milder course of B19V-associated disease is likely due to the increased immune function of HAART-treated patients.

Diagnóstico de laboratorio del parvovirus B19 / Parvovirus B19: Laboratory diagnosis

Parvovirus B19, es el único patógeno humano conocido de los parvovirus. El espectro de enfermedad al cual se encuentra asociado el B19 incluye un amplio rango de enfermedades: eritema infeccioso, síntomas de trombopenia o granulocitopenia, crisis aplástica, o anemia hemolítica en pacientes inmuno comprometidos. El diagnóstico de laboratorio de infección por parvovirus B19 es confirmado principalmente por la detección de anticuerpos antivirales del tipo de IgM por medio de la técnica de ELISA, la cual se encuentra dirigida tanto a epítopes conformacionales como lineales de proteínas de cápside VP1 y VP2. Cuando la respuesta a IgM declina, la presencia de IgG se hace cada vez más evidente en contra de VP1 y VP2, pudiendo ser detectada por inmunofluorescencia, ELISA y Western blot. El empleo de la reacción en cadena de la polimerasa se usa en la actualidad de manera rutinaria como complemento o alternativa de la serología.

Parvovirus B19 (B19) is the only known human pathogenic parvovirus. The spectrum of illness to which B19 is associated includes a wide range of diseases: erythema infectiosum, thrombocytopenia or granulocytopenia, aplastic crisis or hemolytic anemia in immunocompromised patients. The laboratory diagnosis of Parvovirus B19 infection is primarily confirmed by the detection of IgM antiviral antibodies using the ELISA technique, which is directed against both conformational and linear epitopes of VP1 and VP2 capsid. When IgM response declines, an IgG immune-response against structural proteins VP1 and VP2 becomes prominent and can detected by immunofluorescence, ELISA and Western blot. Polymerase chain reaction is now used as a routine analysis as well as complement or alternative to serology.

Seroepidemiological study of human parvovirus B19 among human immunodeficiency virus-infected patients in a medium-sized city in Rio de Janeiro, Brazil

Parvovirus B19 (B-19) may cause chronic anaemia in immunosuppressed patients, including those infected with human immunodeficiency virus (HIV). We studied single serum samples from 261 consecutive HIV-infected patients using an enzyme immunoassay to detect IgG antibodies to B-19. The seroprevalence of B-19-IgG was 62.8 percent. The differences in seroprevalence across gender, age, educational categories, year of collection of the serum samples, clinical and antiretroviral therapy characteristics, CD4+ count, CD4+ and CD8+ percentage and CD4+/CD8+ ratios were neither substantial nor statistically significant. There was a non-significant, inverse association between B-19 seropositivity and plasma HIV load and haemoglobin level. Our results indicated that 37.1 percent of patients might be susceptible to B-19 infection and remained at risk for being infected, mainly during epidemic periods. As B-19 infection can be treated with immune globulin preparations, it may be included in the diagnostic approach toward chronic anaemia in HIV-infected patients.