RESUMO
We surveyed published papers and an international sickle cell disease (SCD) registry to detect susceptibility and clinical course of coronavirus disease 2019 (COVID-19) in SCD patients. COVID-19 presentation was mild in children and moderate in many SCD adults. Regarding increased comorbidities with age, it seems severe COVID-19 to be more common in older SCD patients. Although the overall outcome of COVID-19 was favorable in SCD children, a high rate of pediatric intensive care unit admission should be considered in managing these patients. To explain COVID-19 outcome in SCD patients, the possible benefits of hydroxyurea therapy could be considered. The obtained results should be interpreted, considering low cases from sub-Saharan people, younger age of SCD patients compared to general population, a bias toward registry of the more severe form of disease, the effect of pre-existing comorbidities with multisystem organ damage, and the role of health socio-economic determinants.
Assuntos
Anemia Falciforme/mortalidade , COVID-19/mortalidade , SARS-CoV-2 , Adolescente , Adulto , Fatores Etários , Anemia Falciforme/patologia , Anemia Falciforme/virologia , COVID-19/patologia , Criança , Suscetibilidade a Doenças/mortalidade , Suscetibilidade a Doenças/patologia , Suscetibilidade a Doenças/virologia , Feminino , Humanos , Masculino , Fatores de Risco , Índice de Gravidade de DoençaRESUMO
BACKGROUND: In March 2020, WHO announced Coronavirus Disease 2019 (COVID-19) outbreak a global pandemic. During this pandemic, patients with sickle cell disease (SCD) have been placed in the "high-risk" category of the population. Although there are numerous publications describing COVID-19 in adult patients, pediatric data are still limited. OBSERVATION: Herein, we report case series of 5 sickle cell disease Omani children who got infected with COVID-19; illustrating their different ways of presentation, management and highlighting the outcomes. CONCLUSION: Although SCD patients are considered as a high-risk group, all of the observed patients, and whose cases are reported here, have recovered. A large scale of SCD cases should be studied to reach more conclusive results.
Assuntos
Anemia Falciforme/virologia , COVID-19/complicações , SARS-CoV-2/isolamento & purificação , Anemia Falciforme/diagnóstico , Anemia Falciforme/epidemiologia , Anemia Falciforme/terapia , COVID-19/transmissão , COVID-19/virologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Omã/epidemiologiaRESUMO
BACKGROUND: Although respiratory syncytial virus (RSV) is the leading cause of pediatric lower respiratory tract infections, the burden of RSV in children with sickle cell disease (SCD) is unknown. METHODS: We conducted a retrospective, nested, case-control study of children with SCD <18 years who had respiratory viral panels (RVPs) performed at Children's Healthcare of Atlanta from 2012 to 2019. We abstracted the medical records to describe the demographics, clinical features, and outcomes of children who tested positive for RSV (cases) versus children who tested negative (controls). We calculated the annual incidence of RSV and related hospitalization rates with 95% confidence intervals (CIs) and used multivariate logistic regression to evaluate associations. RESULTS: We identified 3676 RVP tests performed on 2636 patients over seven respiratory seasons resulting in 219/3676 (6.0%) RSV-positive tests among 160/2636 (6.1%) patients. The average annual incidence of laboratory-confirmed RSV infection among children with SCD was 34.3 (95% CI 18.7-49.8) and 3.8 (95% CI 0.5-7.0) cases per 1000 person-years for those <5 years and 5-18 years, respectively. The RSV-related hospitalization rate for children <5 years was 20.7 (95% CI 8.5-32.8) per 1000 person-years. RSV-positive cases were significantly younger than RSV-negative patients (3.8 years vs 7.6 years, P < .001). Of RSV-positive cases, 22 (13.8%) developed acute chest syndrome and nine (5.6%) required intensive care, which was not significantly different from RSV-negative children with SCD. CONCLUSION: RSV infections are common in children with SCD with higher burden in younger patients. RSV is associated with considerable morbidity, including higher rates of hospitalization compared to the general population.
Assuntos
Síndrome Torácica Aguda/epidemiologia , Anemia Falciforme/epidemiologia , Hospitalização/estatística & dados numéricos , Infecções por Vírus Respiratório Sincicial/complicações , Vírus Sincicial Respiratório Humano/patogenicidade , Síndrome Torácica Aguda/patologia , Síndrome Torácica Aguda/virologia , Adolescente , Anemia Falciforme/patologia , Anemia Falciforme/virologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Seguimentos , Georgia/epidemiologia , Humanos , Incidência , Lactente , Masculino , Prognóstico , Estudos Prospectivos , Infecções por Vírus Respiratório Sincicial/virologia , Estudos RetrospectivosRESUMO
BACKGROUND: Patients with sickle cell disease are at higher risk of infections with encapsulated bacteria due to immature immune responses and functional asplenia. We aimed to study our patient population for the emergence of gram-negative organisms other than Salmonella as the cause of osteomyelitis and document a vast decrease in Streptococcus pneumoniae bacteremia rates. METHODS: We conducted a retrospective chart review of 158 patients with sickle cell disease registered at our hospital. Over a period of 13 years, every patient presenting to the emergency department (ED) with fever had their medical record reviewed for blood cultures, wound cultures, and magnetic resonance imaging results for osteomyelitis. RESULTS: The number of patients presenting to the ED with fever was 105, with 581 febrile episodes and 893 blood cultures. Among those, no culture grew Streptococcus pneumoniae, 14 grew coagulase-negative staphylococci (1.5%), one grew Salmonella enterica Paratyphi B, and three grew Salmonella enterica group C (in the same patient). The total number of osteomyelitis episodes in patients with sickle cell disease presenting with fever and documented by imaging was nine (1.5%). In patients with osteomyelitis, organisms were isolated in four patients (44%), including Enterobacter cloacae, Bacteroides, Pseudomonas aeruginosa, and Salmonella enterica group C. CONCLUSIONS: Immunization against Streptococcus pneumoniae and the use of prophylactic penicillin has virtually eliminated pneumococcal bacteremia among our patients. We observed the emergence of gram-negative organisms other than Salmonella as the cause of osteomyelitis in patients with sickle cell disease.
Assuntos
Anemia Falciforme/epidemiologia , Bactérias Gram-Negativas/patogenicidade , Infecções por Bactérias Gram-Negativas/complicações , Hospitalização/estatística & dados numéricos , Osteomielite/epidemiologia , Adolescente , Anemia Falciforme/patologia , Anemia Falciforme/virologia , Criança , Pré-Escolar , Feminino , Seguimentos , Infecções por Bactérias Gram-Negativas/virologia , Humanos , Incidência , Lactente , Recém-Nascido , Líbano/epidemiologia , Masculino , Osteomielite/patologia , Osteomielite/virologia , Prognóstico , Estudos RetrospectivosRESUMO
INTRODUCTION: Preemptive therapy (PET) for cytomegalovirus (CMV) reactivation post allogeneic hematopoietic stem cell transplantation (SCT) was shown to decrease the incidence of CMV disease. However, the optimal PET threshold is elusive. PURPOSE OF THE STUDY: To examine the efficacy of PET initiation at a viral threshold of 1000 copies/mL (1560 IU/mL) in a patient population with high prevalence of CMV seropositive status. PATIENTS AND METHODS: A single center retrospective review of patients that underwent allogeneic SCT was done. RESULTS: A total of 195 allogeneic SCT recipients were included with median follow up of 18.1 (0.7-95.6) months. A total of 178 (91 %) of patients had a positive CMV PCR with median days to initial reactivation post SCT of 17 (1-1187); 129 patients had peak CMV titer < 1000 copies/mL (low titer) whereas the remaining 49 patients had a peak titer ≥ 1000 copies/mL (high titer). 120 (93 %) of patients with low titers cleared spontaneously with median time to clearance of 40 days (4-188). One patient in the high titer group developed CMV disease. At multivariable analysis; age at SCT HR 1.02 (1.004-1.04; 0.017), malignant vs. benign condition HR 9.4 (2.47-61; 0.0005) and cGVHD HR 0.37 (0.2-0.65; 0.0005) were significant for OS. CONCLUSIONS: CMV reactivation post SCT was very common in patients with high prevalence of seropositive status. A PET threshold of 1000 copies/mL (1560 IU/mL) appears desirable as it was associated with spontaneous clearance in over 90 % of patients while minimizing treatment related toxicity. Validation of these observations is warranted.
Assuntos
Quimioprevenção , Infecções por Citomegalovirus/epidemiologia , Infecções por Citomegalovirus/prevenção & controle , Transplante de Células-Tronco Hematopoéticas , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Anemia Aplástica/complicações , Anemia Aplástica/epidemiologia , Anemia Aplástica/terapia , Anemia Aplástica/virologia , Anemia Falciforme/complicações , Anemia Falciforme/epidemiologia , Anemia Falciforme/terapia , Anemia Falciforme/virologia , Antivirais/uso terapêutico , Calibragem , Quimioprevenção/métodos , Quimioprevenção/normas , Citomegalovirus/efeitos dos fármacos , Citomegalovirus/fisiologia , Infecções por Citomegalovirus/complicações , Feminino , Neoplasias Hematológicas/complicações , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/virologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Transplante de Células-Tronco Hematopoéticas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Arábia Saudita/epidemiologia , Estudos Soroepidemiológicos , Condicionamento Pré-Transplante/normas , Transplante Homólogo/efeitos adversos , Carga Viral , Viremia/epidemiologia , Viremia/terapia , Ativação Viral/efeitos dos fármacos , Adulto JovemRESUMO
BACKGROUND: Patients with sickle cell disease (SCD) often require red blood cell (RBC) transfusion for clinical complications, so may be exposed to transfusion-transmitted infections (TTIs). The prevalence of markers for human immunodeficiency virus (HIV), hepatitis C virus (HCV) and B (HBV), human T-cell lymphotropic virus (HTLV-1/2), Chagas disease, and syphilis in an SCD cohort in Brazil were studied. STUDY DESIGN AND METHODS: Clinical history, interview data, blood samples, and medical chart review data were collected during cohort enrollment from November 2013 to May 2015. Serologic markers of infection were assessed. Standard measures of statistical association were calculated, and multivariable models were developed for the most prevalent infections to identify associated factors. RESULTS: Infection markers were evident in 5.2% (144/2779) of the enrolled cohort. Anti-HCV was detected in 69 (2.5%), syphilis antibodies in 34 (1.2%), anti-HTLV-1/2 in 17 (0.6%), HBV surface antigen in 13 (0.5%), Chagas disease antibodies in 13 (0.5%), and anti-HIV in 8 (0.3%) of participants. Factors associated with increased odds of being anti-HCV reactive were older age, illegal drug use, increasing number of RBCs, more than three pain crises in the previous year, and geographic location. Syphilis was associated with older age, females, and smoking history. CONCLUSION: HCV infection was more common in older patients who may have received RBCs before testing was performed on donations, suggesting possible historic transfusion transmission. The cohort showed decreasing rates of infections and a reduction in transfusion transmission markers in younger patients compared to historical literature except for syphilis, indicating contemporary reduced risk of TTI.
Assuntos
Anemia Falciforme/epidemiologia , Transfusão de Sangue/métodos , Infecções Sexualmente Transmissíveis/epidemiologia , Adulto , Anemia Falciforme/virologia , Brasil , Doença de Chagas/metabolismo , Doença de Chagas/virologia , Estudos de Coortes , Feminino , HIV/patogenicidade , Hepacivirus/patogenicidade , Vírus da Hepatite B/patogenicidade , Hepatite C/epidemiologia , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infecções Sexualmente Transmissíveis/virologia , Sífilis/epidemiologia , Sífilis/virologia , Adulto JovemRESUMO
Parvovirus B19 infection causes transient aplastic crisis in sickle cell disease (SCD) due to a temporary interruption in the red blood cell production. Toxicity from hydroxyurea includes anemia and reticulocytopenia, both of which also occur during a transient aplastic crisis event. Hydroxyurea inhibits proliferation of hematopoietic cells and may be immunosuppressive. We postulated that hydroxyurea could exacerbate parvovirus B19-induced aplastic crisis and inhibit the development of specific immune responses in children with SCD. We conducted a retrospective review of parvovirus B19 infection in 330 children with SCD. Altogether there were 120 known cases of aplastic crisis attributed to parvovirus B19 infection, and 12% of children were on hydroxyurea treatment during the episode. We evaluated hematological and immune responses. Children with HbSS or HbSß(0)-thalassemia treated with hydroxyurea, when compared with untreated children, required fewer transfusions and had higher Hb concentration nadir during transient aplastic crisis. Duration of hospital stays was no different between hydroxyurea-treated and untreated groups. Children tested within a week following aplastic crisis were positive for parvovirus-specific IgG. Immune responses lasted for the duration of the observation period, up to 13 years after transient aplastic crisis, and there were no repeat aplastic crisis episodes. The frequencies of parvovirus-specific antibodies in all children with SCD increased with age, as expected due to the increased likelihood of a parvovirus exposure, and were comparable to frequencies reported for healthy children. Approximately one-third of children had a positive parvovirus B19-specific IgG test without a documented history of transient aplastic crisis, and 64% of them were treated with hydroxyurea. Hydroxyurea may reduce requirements for blood transfusions and may attenuate symptoms during transient aplastic crisis episodes caused by parvovirus B19 infections. Children with SCD, whether treated or untreated with hydroxyurea, generate sustained and protective parvovirus B19-specific immune responses.
Assuntos
Anemia Falciforme/complicações , Antidrepanocíticos/uso terapêutico , Hidroxiureia/uso terapêutico , Infecções por Parvoviridae/complicações , Parvovirus B19 Humano , Adolescente , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/virologia , Criança , Pré-Escolar , Transfusão de Eritrócitos , Humanos , Lactente , Estudos RetrospectivosRESUMO
Although xenotropic murine leukemia virus-related virus (XMRV) has been regarded as a laboratory contaminant, it remains one of the most controversial viruses. The objective of the study was to determine if XMRV is present in 44 patients with beta-thalassemia major, 48 with sickle cell disease, and 89 volunteer blood donors. After RNA/ DNA extraction from plasma/buffy coat the samples were screened for XMRV sequences by conserved nested GAG primers. None of the RNA samples showed a positive result. Surprisingly, four DNA samples obtained from blood donors were positive for XMRV provirus. The subsequent phylogenetic analysis revealed that these sequences are identical to the positive control (murine leukemia retrovirus) and are probably consistent with laboratory contamination. XMRV infection (provirus and viral RNA) was absent in multiply transfused patients and volunteer blood donors. The positive result obtained from some blood donors probably reflects laboratory contamination. We believe that XMRV does not pose risk to blood transfusion.
Assuntos
Anemia Falciforme/virologia , Infecções por Retroviridae/virologia , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/isolamento & purificação , Talassemia beta/virologia , Adolescente , Adulto , Animais , Doadores de Sangue , Transfusão de Sangue , Brasil , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/classificação , Vírus Relacionado ao Vírus Xenotrópico da Leucemia Murina/genética , Adulto JovemRESUMO
BACKGROUND: Respiratory syncytial virus (RSV) is a cause of acute chest syndrome (ACS) in sickle cell disease (SCD), but its clinical course and acute complications have not been well characterized. We compared RSV to seasonal influenza infections in children with SCD. PROCEDURE: We defined cases as laboratory-confirmed RSV or seasonal influenza infection in inpatients and outpatients <18 years of age with SCD from 1 September 1993 to 30 June 2011. We used Fisher's exact test to compare proportions, Student's t-test or Wilcoxon rank-sum test to compare continuous variables, and logistic regression to evaluate associations. RESULTS: We identified 64 children with RSV and 91 with seasonal influenza. Clinical symptoms, including fever, cough, and rhinorrhea were similar for RSV and influenza, as were complications, including ACS and treatments for SCD. In a multivariable logistic regression model, older age (OR 1.2 per year, 95% CI [1.02-1.5], P = 0.04), increased white blood cell count at presentation (OR 1.1 per 1,000/µl increase, 95% CI [1.03-1.3], P = 0.008), and a history of asthma (OR 7, 95% [CI 1.3-37], P = 0.03) were independently associated with increased risk of ACS in children with RSV. The hospitalization rate for children with SCD and RSV (40 per 1,000 <5 years and 63 per 1,000 <2 years) greatly exceeds the general population (3 in 1,000 <5 years). CONCLUSIONS: We conclude that RSV infection is often associated with ACS and similar in severity to influenza infection in febrile children with SCD.
Assuntos
Anemia Falciforme/diagnóstico , Vírus da Influenza A/patogenicidade , Influenza Humana/diagnóstico , Infecções por Vírus Respiratório Sincicial/diagnóstico , Vírus Sinciciais Respiratórios/patogenicidade , Síndrome Torácica Aguda/diagnóstico , Síndrome Torácica Aguda/virologia , Anemia Falciforme/virologia , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Febre/diagnóstico , Febre/virologia , Seguimentos , Humanos , Lactente , Masculino , Prognóstico , Estações do AnoRESUMO
Fat embolism syndrome (FES) due to extensive bone marrow necrosis (BMN) in sickle cell disease (SCD) is a potentially under-diagnosed complication associated with severe morbidity and mortality. We identified 58 cases reported in the world literature to date. Typically, patients presented with a seemingly uncomplicated vaso-occlusive crisis (VOC) and subsequently deteriorated rapidly with a drop in their haemoglobin and platelets, development of respiratory failure, encephalopathy and varying degrees of involvement of other systems. Overall mortality in the reported cases was 64% but differed according to the use of transfusion and was 29%, 61% and 91% for patients receiving exchange, top-up or no transfusion respectively. Patients most at risk appear to be those with a "milder" form of SCD as 81% of patients had a genotype other than HbSS and the majority had no history of significant sickle-related complications. Human parvovirus B19 (HPV B19) infection was documented in 24% of cases.
Assuntos
Anemia Falciforme/complicações , Medula Óssea/patologia , Embolia Gordurosa/etiologia , Adolescente , Adulto , Anemia Falciforme/genética , Anemia Falciforme/virologia , Criança , Embolia Gordurosa/mortalidade , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Necrose , Infecções por Parvoviridae/complicações , Parvovirus B19 Humano , Avaliação de Resultados da Assistência ao Paciente , Risco , Adulto JovemRESUMO
BACKGROUND: Human rhinovirus (HRV), human coronavirus (hCoV), human bocavirus (hBoV), and human metapneumovirus (hMPV) infections in children with sickle cell disease have not been well studied. PROCEDURE: Nasopharyngeal wash specimens were prospectively collected from 60 children with sickle cell disease and acute respiratory illness, over a 1-year period. Samples were tested with multiplexed-PCR, using an automated system for nine respiratory viruses, Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Bordetella pertussis. Clinical characteristics and distribution of respiratory viruses in patients with and without acute chest syndrome (ACS) were evaluated. RESULTS: A respiratory virus was detected in 47 (78%) patients. Nine (15%) patients had ACS; a respiratory virus was detected in all of them. The demographic characteristics of patients with and without ACS were similar. HRV was the most common virus, detected in 29 of 47 (62%) patients. Logistic regression showed no association between ACS and detection of HRV, hCoV, hBoV, hMPV, and other respiratory pathogens. Co-infection with at least one additional respiratory virus was seen in 14 (30%) infected patients, and was not significantly higher in patients with ACS (P = 0.10). Co-infections with more than two respiratory viruses were seen in seven patients, all in patients without ACS. Bacterial pathogens were not detected. CONCLUSION: HRV was the most common virus detected in children with sickle cell disease and acute respiratory illness, and was not associated with increased morbidity. Larger prospective studies with asymptomatic controls are needed to study the association of these emerging respiratory viruses with ACS in children with sickle cell disease.
Assuntos
Síndrome Torácica Aguda/virologia , Anemia Falciforme/virologia , Nasofaringe/virologia , Adolescente , Criança , Pré-Escolar , Coronavirus/isolamento & purificação , Feminino , Bocavirus Humano/isolamento & purificação , Humanos , Lactente , Modelos Logísticos , Masculino , Metapneumovirus/isolamento & purificação , Estudos Prospectivos , Rhinovirus/isolamento & purificaçãoAssuntos
Anemia Hemolítica Autoimune/etiologia , Anemia Falciforme/complicações , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano/isolamento & purificação , Anemia Hemolítica Autoimune/tratamento farmacológico , Anemia Falciforme/virologia , Pré-Escolar , Feminino , Heterozigoto , Humanos , Infecções por Parvoviridae/complicações , Prognóstico , Literatura de Revisão como AssuntoRESUMO
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.
Assuntos
Criança , Pré-Escolar , Feminino , Humanos , Masculino , Anemia Falciforme/virologia , Infecções por Parvoviridae/virologia , /genética , Doença Aguda , Anemia Falciforme/complicações , Anticorpos Antivirais/sangue , DNA Viral/análise , Genótipo , Filogenia , Infecções por Parvoviridae/complicações , Carga ViralRESUMO
INTRODUCTION: Microbial burden involving parvovirus B19 infection has been recognised as a major cause of morbidity and mortality in sickle cell anaemia (SCA) patients. Given the recent reports of parvovirus B19 infection in Nigeria and the role of inflammation in sickle cell crisis, knowledge of the relationship between the two may be essential for deploying appropriate interventions in infected patients. This study determined the serum levels of tumour necrosis factor alpha (TNF-α) and C-reactive protein (CRP) as inflammatory markers in Nigerian SCA patients with and without parvovirus B19 infections. METHODS: A total of 64 SCA patients aged 5-25 years and 41 age-matched apparently healthy volunteers with haemoglobin genotypes AA or AS were enrolled with consent into the study. Parvovirus B19 infection and serum levels of TNF-α and CRP were determined by the ELISA method. RESULTS: The overall prevalence rate of parvovirus B19 infection in the study subjects was 13.3%. This rate further showed gender variation and negative correlation with age. Significant (p < 0.05) increases in serum CRP and TNF-α levels, with further elevation in unsteady state SCA patients, were observed in comparison with the control. Unlike the control, 29.6% and 21.9% of the SCA patients elicited TNF-α and CRP above threshold levels, respectively. Parvovirus B19 infection was found to elicit greater increases in these inflammatory markers than in infected non-SCA controls. CONCLUSION: We conclude that parvovirus B19 infection is common in this environment, and that serum TNF-α and CRP are predictors of clinical inflammatory episodes in infected SCA patients.
Assuntos
Anemia Falciforme/sangue , Anemia Falciforme/virologia , Proteína C-Reativa/metabolismo , Infecções por Parvoviridae/sangue , Parvovirus B19 Humano , Fator de Necrose Tumoral alfa/sangue , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Hemoglobinas , Humanos , Inflamação , Masculino , Nigéria , Adulto JovemAssuntos
Anemia Falciforme/virologia , Hepatite Autoimune/virologia , Infecções por Parvoviridae/complicações , Anemia Falciforme/sangue , Anemia Falciforme/fisiopatologia , Pré-Escolar , DNA Viral/sangue , Feminino , Hepatite Autoimune/sangue , Hepatite Autoimune/fisiopatologia , Humanos , Infecções por Parvoviridae/sangue , Infecções por Parvoviridae/fisiopatologia , Infecções por Parvoviridae/virologia , Parvovirus B19 Humano , Reação em Cadeia da Polimerase Via Transcriptase Reversa , ViremiaRESUMO
BACKGROUND: The 2009 novel influenza A (H1N1) pandemic has had profound public health implications all over the world. The majority of patients infected with the novel strain have recovered uneventfully. However, certain populations have been defined who appear to be at increased risk of complications due to H1N1 infections. This review summarizes the clinical course of five patients with sickle cell, four of whom had confirmed H1N1 infection, and one whom had a presumed H1N1 infection. PROCEDURE: The clinical presentation, hospital course, and treatment of five pediatric patients with sickle-cell disease and H1N1 infection were reviewed retrospectively. RESULTS: In this case series, our patients experienced complications such as the acute chest syndrome, acute marrow suppression of red cell production, pain crisis, and hematuria. CONCLUSIONS: In this population, who are at increased risk for bacterial superinfection as well as complications from the influenza virus itself, vigilance toward diagnosis and aggressive treatment will continue to be important as long as the novel virus is in circulation.
Assuntos
Anemia Falciforme/complicações , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/etiologia , Síndrome Torácica Aguda/etiologia , Adolescente , Anemia Falciforme/virologia , Criança , Pré-Escolar , Hematúria/etiologia , Humanos , Lactente , Masculino , Dor/etiologia , Estudos Retrospectivos , Superinfecção/etiologiaRESUMO
For many diseases, it is difficult or impossible to establish a definitive diagnosis because a perfect "gold standard" may not exist or may be too costly to obtain. In this paper, we propose a method to use continuous test results to estimate prevalence of disease in a given population and to estimate the effects of factors that may influence prevalence. Motivated by a study of human herpesvirus 8 among children with sickle-cell anemia in Uganda, where 2 enzyme immunoassays were used to assess infection status, we fit 2-component multivariate mixture models. We model the component densities using parametric densities that include data transformation as well as flexible transformed models. In addition, we model the mixing proportion, the probability of a latent variable corresponding to the true unknown infection status, via a logistic regression to incorporate covariates. This model includes mixtures of multivariate normal densities as a special case and is able to accommodate unusual shapes and skewness in the data. We assess model performance in simulations and present results from applying various parameterizations of the model to the Ugandan study.
Assuntos
Anemia Falciforme/virologia , Infecções por Herpesviridae/epidemiologia , Herpesvirus Humano 8/isolamento & purificação , Modelos Biológicos , Modelos Estatísticos , Adolescente , Anemia Falciforme/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Infecções por Herpesviridae/complicações , Infecções por Herpesviridae/diagnóstico , Humanos , Técnicas Imunoenzimáticas , Lactente , Prevalência , Uganda/epidemiologiaRESUMO
Symptomatic manifestations of parvovirus B19 infection range from harmless conditions such as 5th disease of the child or arthropathy of the middle-aged woman to life threatening disease such as transient aplastic crisis during sickle cell disease, chronic anaemia in immunodeficiency states or hydrops foetalis during pregnancy. Increasing knowledge of parvovirus B19 has led to a better understanding about how a single and unvariant erythrovirus causes such a variety of diseases. The importance of age, hematopoietic and immune status has been raised and besides, effective diagnostic assays, treatments and possibly vaccine have been developed that can be rationally used at the light of this knowledge.
Assuntos
Infecções por Parvoviridae/fisiopatologia , Parvovirus B19 Humano/fisiologia , Adulto , Fatores Etários , Anemia/virologia , Anemia Falciforme/virologia , Artrite Infecciosa/virologia , Criança , Suscetibilidade a Doenças/fisiopatologia , Eritema Infeccioso/fisiopatologia , Feminino , Humanos , Hidropisia Fetal/virologia , Síndromes de Imunodeficiência/virologia , Pessoa de Meia-Idade , Infecções por Parvoviridae/diagnóstico , Infecções por Parvoviridae/terapia , Parvovirus B19 Humano/imunologia , Gravidez , Vacinas ViraisRESUMO
Among 233 children, Kaposi sarcoma-associated herpesvirus (KSHV) DNA was detected in 43% of children seropositive for both K8.1 and orf73, in 29% of children seropositive for K8.1 only, in 14% of children seropositive for orf73 only, and in 7% of children seronegative for both K8.1 and orf73; among 228 mothers, KSHV DNA was detected in 27%, 25%, 4%, and 1%, respectively. KSHV DNA was detected more frequently and at higher levels in saliva than in buffy-coat samples and in children than in mothers. In both children and mothers, detection in saliva was associated with detection in peripheral blood. Detection was associated with K8.1 seropositivity, younger age, and high household density, indicating the importance of in-household person-to-person transmission, likely via saliva.
Assuntos
Anemia Falciforme/virologia , DNA Viral/análise , Transmissão de Doença Infecciosa , Infecções por Herpesviridae/transmissão , Herpesvirus Humano 8/isolamento & purificação , Saliva/virologia , Adolescente , Adulto , Idoso , Anemia Falciforme/sangue , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Feminino , Infecções por Herpesviridae/sangue , Infecções por Herpesviridae/virologia , Herpesvirus Humano 8/genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , UgandaRESUMO
PURPOSE: To investigate the prevalence and clinical consequences of previous parvovirus B19 exposure in a large cohort of pediatric patients with sickle cell anemia (SCA). METHODS: Prospective serologic testing for previous parvovirus B19 exposure was performed in steady-state pediatric patients with SCA, either prior to starting hydroxyurea therapy or in preparation for transition to the adult service. A retrospective chart review was performed to ascertain whether patients had a documented history of a transient aplastic crisis. RESULTS: The prevalence of serologic evidence of previous parvovirus infection increased with age. The overall prevalence in 102 children with SCA was 53%, ranging from 44% between 5 and 9 years of age to 71% between 17 and 21 years of age. Only 27% of patients had a previous clinically recognized transient aplastic crisis. CONCLUSIONS: By the teenage years, most pediatric patients with SCA have serologic evidence of previous parvovirus B19 exposure. However, subclinical parvovirus infection appears to be common in children with SCA, since most patients have no documented previous transient aplastic crisis.