Clinical, biochemical and molecular evidence for the sickle cell anemia （SCA） crisis in Nigerian patients arising from parvovirus b19 infection remains inadequate. This study determined the prevalence and correlates...Clinical, biochemical and molecular evidence for the sickle cell anemia （SCA） crisis in Nigerian patients arising from parvovirus b19 infection remains inadequate. This study determined the prevalence and correlates of antiparvovirus b19 antibodies in a population of SCA patients and non-SCA healthy controls in Lagos, Nigeria. In this prospective cross-sectional study, we enrolled 73 confirmed SCA patients from 5 district hospitals in Lagos and 81 sex and age-matched non-SCA healthy controls. Serum sample from each study participant was screened for anti-parvovirus b19 by ELISA and PCR techniques. Standard biomedical assays were also done. Anti-parvovirus b19 IgM and IgG antibodies were detected in 22 （14.3%） and 97 （62.9%） of the 154 sera screened, 13 （17.8%） and 45 （61.6%） in SCA patients; 9 （11.1%） and 52 （64.2%） in non-SCA controls. The overall seronegativity rate was 19.5%. Parvovirus B19 DNA was found in 2 （11.1%） of the 18 IgM seropositive SCA serum samples screened. On the whole, parvovirus b19 infection was more commonly asymptomatic in non-SCA controls but caused significant elevation in liver enzymes in infected SCA patients （P 〈 0.05）. The risk of acute parvovirus b19 infection increased 65 times during unsteady state among the SCA patients. Although no deaths of infected patients were recorded during the study, age below 12 years, hospitalization and overcrowded environment were risk factors for infection. We conclude that parvovirus b19 is common in SCA patients, incurring greater susceptibility to infections.展开更多
Objective: To assess the occurrence and pattern of Toll-like receptor 4(TLR4) cosegregated genotypes among children with Plasmodium falciparum malaria in Nigeria.Methods: In this case-control study, a total of 79 Plas...Objective: To assess the occurrence and pattern of Toll-like receptor 4(TLR4) cosegregated genotypes among children with Plasmodium falciparum malaria in Nigeria.Methods: In this case-control study, a total of 79 Plasmodium falciparum infected children aged 2–7 years and 105 age-matched uninfected controls of Yoruba descents in Lagos were studied. The extracted DNA samples were used for TLR4 genotyping at codons 299(Asp > Gly) and 399(Thr > Ile) by PCR-restriction fragment length polymorphism. Malaria infection was diagnosed by blood smear microscopy and infected children were stratified into asymptomatic, uncomplicated and severe malaria sub-groups.Malnutrition was determined by measuring the mid upper arm circumference and anemia was defined as hemoglobin < 11 g/dL.Results: The proportions of children with acute malnutrition and severe anemia were12.0% and 3.2%, respectively. Parasitemia and malnutrition were not correlated and four distinct patterns of TLR4 genotypes were found in the study population: Asp299Asp/Thr399Thr(90.2%), Asp299Gly/Thr399Thr(4.3%), Gly299Gly/Thr399Thr(3.8%) and Asp299Gly/Thr399Ile(1.6%). These genotypes did not differ significantly(P > 0.05) in frequency between infected and non-infected children. However, low and high occurrences of the TLR4 Asp299Asp/Thr399 Thr and Asp299Gly/Thr399 Thr genotypes were observed in the severe malaria subgroup.Conclusions: This study reveals a protective role for TLR4 Asp299Gly/Thr399 Ile and Asp299Asp/Thr399 Thr genotypes against severe malaria in Nigerian children.展开更多
文摘Clinical, biochemical and molecular evidence for the sickle cell anemia （SCA） crisis in Nigerian patients arising from parvovirus b19 infection remains inadequate. This study determined the prevalence and correlates of antiparvovirus b19 antibodies in a population of SCA patients and non-SCA healthy controls in Lagos, Nigeria. In this prospective cross-sectional study, we enrolled 73 confirmed SCA patients from 5 district hospitals in Lagos and 81 sex and age-matched non-SCA healthy controls. Serum sample from each study participant was screened for anti-parvovirus b19 by ELISA and PCR techniques. Standard biomedical assays were also done. Anti-parvovirus b19 IgM and IgG antibodies were detected in 22 （14.3%） and 97 （62.9%） of the 154 sera screened, 13 （17.8%） and 45 （61.6%） in SCA patients; 9 （11.1%） and 52 （64.2%） in non-SCA controls. The overall seronegativity rate was 19.5%. Parvovirus B19 DNA was found in 2 （11.1%） of the 18 IgM seropositive SCA serum samples screened. On the whole, parvovirus b19 infection was more commonly asymptomatic in non-SCA controls but caused significant elevation in liver enzymes in infected SCA patients （P 〈 0.05）. The risk of acute parvovirus b19 infection increased 65 times during unsteady state among the SCA patients. Although no deaths of infected patients were recorded during the study, age below 12 years, hospitalization and overcrowded environment were risk factors for infection. We conclude that parvovirus b19 is common in SCA patients, incurring greater susceptibility to infections.
文摘Objective: To assess the occurrence and pattern of Toll-like receptor 4(TLR4) cosegregated genotypes among children with Plasmodium falciparum malaria in Nigeria.Methods: In this case-control study, a total of 79 Plasmodium falciparum infected children aged 2–7 years and 105 age-matched uninfected controls of Yoruba descents in Lagos were studied. The extracted DNA samples were used for TLR4 genotyping at codons 299(Asp > Gly) and 399(Thr > Ile) by PCR-restriction fragment length polymorphism. Malaria infection was diagnosed by blood smear microscopy and infected children were stratified into asymptomatic, uncomplicated and severe malaria sub-groups.Malnutrition was determined by measuring the mid upper arm circumference and anemia was defined as hemoglobin < 11 g/dL.Results: The proportions of children with acute malnutrition and severe anemia were12.0% and 3.2%, respectively. Parasitemia and malnutrition were not correlated and four distinct patterns of TLR4 genotypes were found in the study population: Asp299Asp/Thr399Thr(90.2%), Asp299Gly/Thr399Thr(4.3%), Gly299Gly/Thr399Thr(3.8%) and Asp299Gly/Thr399Ile(1.6%). These genotypes did not differ significantly(P > 0.05) in frequency between infected and non-infected children. However, low and high occurrences of the TLR4 Asp299Asp/Thr399 Thr and Asp299Gly/Thr399 Thr genotypes were observed in the severe malaria subgroup.Conclusions: This study reveals a protective role for TLR4 Asp299Gly/Thr399 Ile and Asp299Asp/Thr399 Thr genotypes against severe malaria in Nigerian children.
