RESUMO
Using convalescent plasma as immunotherapy is an old method for treatment of infectious diseases. Several countries have recently allowed the use of such therapy for the treatment of COVID-19 patients especially those who are critically ill. A similar program is currently being tested in Egypt. Here, we tested 227 plasma samples from convalescent donors in Egypt for neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using a microneutralization (MN) assay. A third of the tested samples did not have antibody titers and 58% had titers between 1:10 and 1:80. Only 12% had titers >1:160. We also compared MN assays using different virus concentrations, plaque reduction neutralization (PRNT) assays, and a chemiluminescence assay that measures immunoglobulin G (IgG) binding to N and S proteins of SARS-CoV-2. Our results indicated that a MN assay using 100 TCID50/ml provides comparable results to PRNT and allows for high throughput testing.
RESUMO
Since iron overload is the commonest cause of morbidity and mortality in ß thalassemia major (ß-TM), it represents one major target in therapeutic management of the disease. The recently discovered erythroid regulator, erythroferrone (ERFE), governed by high levels of erythropoietin, was found to suppress hepcidin expression, thus increasing iron availability for developing erythroid progenitors. We aimed to investigate ERFE levels in Egyptian ß-TM patients as an attempt to understand its role in the prediction of iron overload states. Our study included 70 ß-TM patients, divided into two subgroups according to the degree of iron overload, and 30 sex and age-matched healthy subjects. ERFE gene expression was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR), and serum hepcidin was measured using enzyme-linked immunosorbent assay (ELISA) technique. Both ERFE gene expression levels and transferrin saturation (TS%) values were able to discriminate among cases with different degrees of iron overload, in contrast to hepcidin. TS% was acknowledged as the best predictor of iron overload (AUC 0.893) in comparison with serum hepcidin and ERFE gene levels (AUC 0.807 and 0.677, respectively), and ERFE gene expression was an independent predictor for the estimated TS%. In conclusion, we suggest that using the ERFE gene expression, combined with serum hepcidin estimation, can substantiate the role of estimated TS% as a promising tool in screening for iron overload in ß-TM patients.
Assuntos
Regulação da Expressão Gênica , Sobrecarga de Ferro/sangue , Hormônios Peptídicos/sangue , Talassemia beta/sangue , Adolescente , Criança , Estudos Transversais , Egito , Feminino , Hepcidinas/sangue , Humanos , Ferro/sangue , Masculino , Reação em Cadeia da Polimerase em Tempo RealRESUMO
ß-Thalassemia (ß-thal) represents a major health problem worldwide and particularly in Egypt. Its prevention, compared to treatment, is cost-effective, possible and practical. In this study we evaluate a proposed paradigm for detection of the ß-thal carrier state. The present study included 1627 children and adolescents of both sexes, presenting as outpatients to clinics of Ain-Shams University Hospitals, Cairo, Egypt, from November 1 2009 to June 30 2010. In the first phase, after performing a complete blood count (CBC), 280 microcytic hypochromic patients were selected. These cases were further analyzed by iron profile and high performance liquid chromatography (HPLC); in the second phase, hybridization detected 22 common ß-globin mutations in 74.0% of the suspected cases. Thus, by HPLC, the Hb A2 level of >3.5% provided 100.0% sensitivity, 70.0% specificity, 75.0% positive predictive value (PPV), 100.0% negative predictive value (NPV) and accuracy of 70.0% to identify ß-thal trait and at a cut-off of 4.0%, it provided 97.4% sensitivity, 72.7% specificity, 92.6% PPV, 88.8% NPV and a diagnostic accuracy of 92%. High performance liquid chromatography is a reliable and cost effective primary screening tool for ß-thal trait at a Hb A2 level of ≥4.0%, while molecular testing is mandatory only for selected cases with borderline Hb A2 values between 3.5 and 4.0%.
Assuntos
Heterozigoto , Mutação , Globinas beta/genética , Talassemia beta/genética , Adolescente , Criança , Pré-Escolar , Índices de Eritrócitos , Eritrócitos/patologia , Feminino , Frequência do Gene , Testes Genéticos , Humanos , Lactente , Ferro/sangue , Ferro/metabolismo , Masculino , Programas de Rastreamento , Fenótipo , Prevalência , Sensibilidade e Especificidade , Adulto Jovem , Talassemia beta/diagnóstico , Talassemia beta/epidemiologiaRESUMO
A total of 220 enteroadherent Escherichia coli were identified from 729 Egyptian children with diarrhea using the HEp-2 adherence assay. Enteropathogenic E.coli (EPEC = 38) was common among children <6 months old and provoked vomiting, while diffuse-adhering E.coli (DAEC = 109) induced diarrheal episodes of short duration, and enteroaggregative E.coli (EAEC = 73) induced mild non-persistent diarrhea. These results suggest that EPEC is associated with infantile diarrhea in Egyptian children.
Assuntos
Diarreia Infantil/epidemiologia , Diarreia Infantil/microbiologia , Escherichia coli Enteropatogênica/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Escherichia coli/classificação , Criança , Pré-Escolar , Diarreia Infantil/diagnóstico , Egito/epidemiologia , Escherichia coli Enteropatogênica/genética , Ensaio de Imunoadsorção Enzimática , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/diagnóstico , Fezes/microbiologia , Feminino , Humanos , Lactente , Masculino , Fenótipo , PrevalênciaRESUMO
BACKGROUND: Screening donated blood for transfusion-transmissible infections is considered an important strategy for maximising the safety of blood transfusions. MATERIALS AND METHODS: A total of 17,118 donors, classified into two groups--family replacement donors and voluntary non-remunerated donors--were investigated for hepatitis B virus (HBV) surface antigen and antibodies against hepatitis C virus (HCV), human immunodeficiency virus (HIV) and Treponema pallidum. In addition cytomegalovirus (CMV) antibodies were searched for in 160 donors (80 from each group). All the laboratory tests were done using enzyme-linked immunosorbent assays. RESULTS: Of the total cohort of donors, 87.7% were family donors and 12.3% were voluntary non-remunerated donors. There was a highly significant difference in age and gender between the two types of donors with voluntary donors being much younger and including a much higher proportion of male donors than female donors. The prevalences of HBV, HCV and CMV IgG were much higher in family donors than in voluntary donors, with the differences being highly statistically significant. There was also a significantly higher prevalence of syphilis among family replacement donors. As regards HIV and CMV IgM, significant differences were not detected between the two groups. DISCUSSION: The results of our study clearly showed that the prevalence of transfusion-transmissible infections is much higher among family replacement donors than among voluntary donors, and that voluntary donors are the best way of achieving safer blood.
Assuntos
Doadores de Sangue , Seleção do Doador/métodos , Família , Segurança , Adolescente , Adulto , Fatores Etários , Anticorpos Antibacterianos/sangue , Anticorpos Antivirais/sangue , Patógenos Transmitidos pelo Sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Sífilis/sangue , Sífilis/prevenção & controle , Sífilis/transmissão , Treponema pallidum , Viroses/sangue , Viroses/prevenção & controle , Viroses/transmissão , VírusRESUMO
INTRODUCTION: We aimed to identify potential risk factors for intussusception (ISS) among children presenting to two pediatric hospitals in Egypt. METHODOLOGY: In this case-control study, enrolled children < 3 years old with ISS (confirmed radiologically and/or surgically) were matched by age and gender to controls admitted with acute non-abdominal surgical illnesses. Stool samples were collected and tested for various enteric bacteria, rotavirus, enteric adenoviruses (EA, 40 and 41) and astroviruses using commercially available ELISA diagnostic kits. RESULTS: From December 2004 to May 2009, 158 cases and 425 matched controls were enrolled. A history of diarrhoea and cough over the preceding four weeks of interview were more common in cases than controls, respectively. Children with mothers who had secondary education and above were 2.2 times more likely to have ISS than those whose mothers had a lower level of education. In spite of the low detection rate of EA infection (regardless of diarrhoea history) and asymptomatic rotavirus infection, they were detected in higher frequencies in cases than controls; however, infection with astrovirus and bacterial pathogens did not appear to be associated with increased risk of ISS. CONCLUSIONS: History of diarrhoea and cough over the four weeks preceding the study and maternal education above secondary level were potential risk factors for ISS. EA and asymptomatic rotavirus infection were detected in higher frequencies among cases than controls; however, association with ISS cannot be confirmed. Additional research is needed to confirm these findings and evaluate the pathogenesis which may link such infections with ISS.
Assuntos
Gastroenterite/complicações , Intussuscepção/complicações , Viroses/complicações , Infecções por Adenovirus Humanos/complicações , Infecções por Adenovirus Humanos/virologia , Adenovírus Humanos/isolamento & purificação , Estudos de Casos e Controles , Pré-Escolar , Egito , Fezes/microbiologia , Fezes/virologia , Feminino , Gastroenterite/virologia , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Masculino , Fatores de Risco , Rotavirus/isolamento & purificação , Infecções por Rotavirus/complicações , Infecções por Rotavirus/virologia , Viroses/virologiaRESUMO
Rotavirus type surveillance is essential to assess the success of rotavirus vaccines. Rotavirus strains collected in 2000-2002 during hospital-based surveillance for diarrhea in Egyptian children were genotyped. Of the 259 (25.2%) rotavirus-positive specimens, 82.4% were common strains (G1p[8], G2p[4], G4p[8]), and the emergent G9 type was detected in 5.3% of samples.
Assuntos
Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Rotavirus/genética , Pré-Escolar , Egito/epidemiologia , Genótipo , Hospitais , Humanos , Lactente , Recém-Nascido , Rotavirus/classificaçãoRESUMO
BACKGROUND: Preparedness for an H5N1 influenza pre-pandemic requires effective and well-tolerated emergency vaccination strategies that provide both pandemic strain-specific and heterologous protection. OBJECTIVES: This was a pivotal study for the regulatory approval process for a candidate MF59-adjuvanted H5N1 vaccine. Its goals were to identify the preferred primary 2-dose vaccination schedule in adults and to assess whether the vaccine met European Committee for Medicinal Products for Human Use (CHMP) licensure criteria. METHODS: Healthy volunteers aged 18 to 60 years received 1 of 4 randomized schedules in which the 2 doses of vaccine were separated by a 1-, 2-, 3-, or 6-week interval. Three blood samples (~20 mL(-1)) were obtained from each subject: the first sample, immediately before administration of the first dose of vaccine; the second, immediately before administration of the second dose; and the third, 21 days after administration of the second dose. Hemagglutination inhibition (HI), microneutralization (MN), and single radial hemolysis (SRH) were assayed after each dose. Immunogenicity was assessed based on the CHMP licensure criteria for annual influenza vaccines (number of seroconversions or significant increase in HI titer >40%; mean geometric increase >2.5; and proportion of subjects achieving an HI titer ≥40 or SRH titer >25 mm(2) should be >70% [seroprotection]). Subjects recorded all adverse events occurring within 7 days of vaccine administration; information on any serious adverse events was collected throughout the study (duration, 202 days). RESULTS: All study participants (N = 240) were white, with a mean age of 33 years and a mean body mass index of 24.6 kg/m(2). Equal numbers of men and women were assigned to each vaccination schedule. The CHMP criterion for seroprotection was achieved when the 2 doses of vaccine were separated by 2 (76%), 3 (72%), and 6 (79%) weeks; similar results were obtained on MN and SRH analysis. On the SRH analysis, the candidate vaccine showed a heterologous immune response to the H5N1/turkey/Turkey/1/05 (NIBRG-23; clade 2) influenza antigen. The vaccine met 2 of the 3 European licensure criteria, with seroconversion rates of 69% and 65% in the groups assigned to a 2- and 3-week interval between doses, respectively, and geometric mean ratios of 4.3 and 4.5. There were no serious adverse events related to vaccination. The most common adverse events reported within 7 days of the first and second doses of vaccine were mild to moderate injection-site pain (63%-73% and 34%-48%, respectively) and fatigue (25%-30% and 13%-24%). CONCLUSIONS: Two 7.5-µg doses of MF59-adjuvanted H5N1 influenza vaccine given 2, 3, or 6 weeks apart afforded H5N1-specific immunity and met the CHMP licensure criterion for seroprotection in these healthy volunteers. Clinically relevant levels of heterologous immunity were observed when the 2 doses of vaccine were administered either 2 or 3 weeks apart; however, the licensure criterion for seroprotection was not met in this case.
Assuntos
Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza , Influenza Humana/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/efeitos adversos , Adolescente , Adulto , Anticorpos Antivirais/sangue , Esquema de Medicação , Feminino , Hemaglutinação/efeitos dos fármacos , Testes de Inibição da Hemaglutinação , Hemólise/efeitos dos fármacos , Humanos , Imunização Secundária , Memória Imunológica/efeitos dos fármacos , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/efeitos adversos , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Polissorbatos/administração & dosagem , Polissorbatos/efeitos adversos , Esqualeno/administração & dosagem , Esqualeno/efeitos adversos , Esqualeno/imunologia , Adulto JovemRESUMO
BACKGROUND: Most studies of Campylobacter infection triggering Guillain-Barré Syndrome (GBS) are conducted in western nations were Campylobacter infection and immunity is relatively rare. In this study, we explored Campylobacter infections, Campylobacter serotypes, autoantibodies to gangliosides, and GBS in Egypt, a country where Campylobacter exposure is common. METHODS: GBS cases (n = 133) were compared to age- and hospital-matched patient controls (n = 374). A nerve conduction study was performed on cases and a clinical history, serum sample, and stool specimen obtained for all subjects. RESULTS: Most (63.3%) cases were demyelinating type; median age four years. Cases were more likely than controls to have diarrhea (29.5% vs. 22.5%, Adjusted Odds Ratio (ORa) = 1.69, P = 0.03), to have higher geometric mean IgM anti-Campylobacter antibody titers (8.18 vs. 7.25 P<0.001), and to produce antiganglioside antibodies (e.g., anti-Gd1a, 35.3 vs. 11.5, ORa = 4.39, P<0.0001). Of 26 Penner:Lior Campylobacter serotypes isolated, only one (41:27, C. jejuni, P = 0.02) was associated with GBS. CONCLUSIONS: Unlike results from western nations, data suggested that GBS cases were primarily in the young and cases and many controls had a history of infection to a variety of Campylobacter serotypes. Still, the higher rates of diarrhea and greater antibody production against Campylobacter and gangliosides in GBS patients were consistent with findings from western countries.
Assuntos
Infecções por Campylobacter/complicações , Síndrome de Guillain-Barré/microbiologia , Adolescente , Adulto , Idoso , Infecções por Campylobacter/imunologia , Criança , Pré-Escolar , Egito , Gangliosídeos/imunologia , Síndrome de Guillain-Barré/etiologia , Síndrome de Guillain-Barré/imunologia , Humanos , Lactente , Pessoa de Meia-Idade , Adulto JovemRESUMO
In a cross-sectional study of children <60 months old from Fayoum, Egypt, presenting with diarrhea, 46% (162/356) had detectable enteric pathogens. Bacterial pathogens were identified in 25% (89/356), whereas rotavirus and Cryptosporidium were detected in 21% (54/253) and 15% (39/253), respectively. Cryptosporidium is an important pathogen in this region.
Assuntos
Criptosporidiose/complicações , Diarreia Infantil/microbiologia , Diarreia Infantil/virologia , Diarreia/microbiologia , Diarreia/virologia , Vigilância da População , Distribuição de Qui-Quadrado , Pré-Escolar , Estudos Transversais , Criptosporidiose/epidemiologia , Diarreia/epidemiologia , Diarreia Infantil/epidemiologia , Egito/epidemiologia , Humanos , Lactente , Recém-Nascido , Estatísticas não ParamétricasRESUMO
To identify enteropathogens for vaccine development, we implemented clinic-based surveillance for severe pediatric diarrhea in Egypt's Nile River Delta. Over 2 years, a physician clinically evaluated and obtained stool samples for microbiology from patients with diarrhea and less than 6 years of age. In the first (N = 714) and second clinic (N = 561), respectively, 36% (N = 254) and 46% (N = 260) of children were infected with rotavirus, enterotoxigenic Escherichia coli (ETEC), Campylobacter, or Shigella. When excluding mixed rotavirus-bacterial infections, for the first and second clinic, 23% and 10% had rotavirus-associated diarrhea, and 14% and 17% had ETEC-associated diarrhea, respectively. Campylobacter-associated diarrhea was 1% and 3%, and Shigella-associated diarrhea was 2% and 1%, respectively, for the two clinics. Rotavirus-associated diarrhea peaked in late summer to early winter, while bacterial agents were prevalent during summer. Rotavirus-associated cases presented with dehydration, vomiting, and were often hospitalized. Children with Shigella- or Campylobacter-associated diarrhea reported as watery diarrhea and rarely dysentery. ETEC did not have any clinically distinct characteristics. For vaccine development and/or deployment, our study suggests that rotavirus is of principle concern, followed by ETEC, Shigella, and Campylobacter.
Assuntos
Infecções Bacterianas/epidemiologia , Diarreia/microbiologia , Diarreia/virologia , Vigilância da População , Infecções por Rotavirus/epidemiologia , Infecções Bacterianas/microbiologia , Pré-Escolar , Diarreia/epidemiologia , Egito/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estações do AnoRESUMO
Over a 2-year period, the prevalence and clinical characteristics of Cryptosporidium-associated diarrhea in the Nile River Delta of Egypt was studied. A stool sample was obtained from children with diarrhea attending one of two study hospitals and of the 1275 children evaluated, 214 (17%) were found to be infected with Cryptosporidium. Younger age was a risk factor for developing Cryptosporidium-associated diarrhea. Children <12 months of age were 2.4 times more likely to be infected with Cryptosporidium (p<0.01) and children 12 to 23 months were 1.9 (p<0.05) times more likely to be infected with the organism as compared to older children. Breastfeeding had a trend towards protection against Cryptosporidium-associated diarrhea (p=0.07). Clinical findings associated with Cryptosporidium diarrhea included vomiting, persistent diarrhea and the need for hospitalization. Our data suggest that Cryptosporidium is common in Egyptian children and may be associated with severe diarrhea.
Assuntos
Criptosporidiose/epidemiologia , Cryptosporidium parvum/isolamento & purificação , Diarreia/epidemiologia , Diarreia/parasitologia , Distribuição por Idade , Animais , Pré-Escolar , Estudos de Coortes , Criptosporidiose/diagnóstico , Egito/epidemiologia , Fezes/parasitologia , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Análise Multivariada , Probabilidade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Distribuição por SexoRESUMO
BACKGROUND: We conducted a nested case-control study in 397 rural Egyptian children <36 months of age to assess the correlation between serum levels of antibodies against toxin and colonization factors (CFs) and the risk of homologous enterotoxigenic Escherichia coli (ETEC) diarrhea. METHODS: Active case detection was performed via semiweekly home visits, and blood was obtained at 3-month intervals. After each serosurvey, case subjects were selected from children experiencing a CF antigen (CFA)/I-, CFA/II-, CFA/IV-, or heat-labile enterotoxin (LT)-ETEC diarrheal episode during the subsequent 3 months. Up to 5 control subjects per case subject were selected from children who did not experience an ETEC diarrheal episode during the corresponding interval. Serum titers of immunoglobulin G antibodies against CFA/I, coli surface antigen (CS) 3, CS6, and LT were measured by enzyme-linked immunosorbant assay. RESULTS: The distribution of serum titers of LT, CS3, and CS6 antibodies did not differ between the case and control subjects. For children <18 months of age, serum titers of CFA/I antibody were inversely related to the risk of CFA/I-ETEC diarrhea; reciprocal serum titers of CFA/I antibody > or =76 were associated with a 77% reduction in the odds of CFA/I-ETEC diarrhea. CONCLUSION: Induction of reciprocal serum titers of antibodies against CFA/I within or above the 76-186 range should be further evaluated as a predictor for assessment of the ability of candidate vaccines to protect against CFA/I-ETEC diarrhea.
Assuntos
Anticorpos Antibacterianos/sangue , Toxinas Bacterianas/imunologia , Diarreia/microbiologia , Diarreia/prevenção & controle , Enterotoxinas/imunologia , Infecções por Escherichia coli/imunologia , Proteínas de Escherichia coli/imunologia , Escherichia coli/imunologia , Proteínas de Bactérias/análise , Proteínas de Bactérias/imunologia , Toxinas Bacterianas/análise , Estudos de Casos e Controles , Pré-Escolar , Egito , Enterotoxinas/análise , Ensaio de Imunoadsorção Enzimática , Escherichia coli/patogenicidade , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/análise , Feminino , Proteínas de Fímbrias/análise , Proteínas de Fímbrias/imunologia , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Fatores de Virulência/análise , Fatores de Virulência/imunologiaRESUMO
The incidence of enterotoxigenic Escherichia coli diarrhea among Egyptian children was 1.5 episodes per child per year and accounted for 66% of all first episodes of diarrhea after birth. The incidence increased from 1.7 episodes per child per year in the first 6 months of life to 2.3 in the second 6 months and declined thereafter.