RESUMO
OBJECTIVES: To determine the spectrum of serum immunoreactive erythropoietin (SIE) levels amongst HIV-infected children aged < 13 years in relation to the levels among healthy children as well as those with renal failure; to examine the relationship between clinical and laboratory parameters and SIE levels. DESIGN: A cross-sectional study with a descriptive non-interventional format. HIV-infected Canadian subjects were recruited through four tertiary Canadian and one Bahamian centre. Children with renal failure and healthy children were recruited from one of the Canadian centres. METHODS: Study subjects had clinical and laboratory profiles determined at baseline and at each of five follow-up periods over 1 year. SIE levels were measured by radioimmunoassay with a normal range of 12-28 IU/I. Data handling and statistical functions were performed by the Canadian HIV Trials Network. RESULTS: The study enrolled 133 HIV-infected subjects and 38 controls. Of these, 117 HIV-infected subjects, 24 healthy controls, and 11 controls with renal failure were eligible for analysis. The median age of infected subjects was 44 months, whereas that of healthy controls was 56 months, and 95 months for controls with renal failure. The median SIE levels were 14 and 11 IU/I for subjects with renal failure and healthy subjects, respectively. The median SIE level was 61 IU/I among zidovudine (ZDV)-treated subjects and 22 IU/I among ZDV-naive HIV-infected subjects. HIV-infected children almost invariably had SIE levels < 200 IU/I. The median SIE levels amongst HIV-infected subjects whose hemoglobin levels were < 100 g/l were 98 and 31 IU/I for ZDV-treated and ZDV-naive subjects, respectively (P = 0.002). This difference in median SIE levels between ZDV-treated subjects and ZDV-naive subjects was also observed among subjects whose hemoglobin levels were > 100 g/l (median, 58 and 15 IU/l, respectively; P < 0.001). Hemoglobin level was the most important predictor of log10 SIE (P < 0.01 for ZDV-treated and ZDV-naive subjects). CONCLUSIONS: SIE levels amongst HIV-infected children were affected by HIV infection, use of ZDV, and presence or absence of anemia. SIE levels amongst HIV-infected children were generally lower than 200 IU/I. This characterization of SIE levels will facilitate clinical trials of exogenous recombinant human erythropoietin in HIV-infected children with anemia.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Eritropoetina/sangue , Infecções por HIV/sangue , Zidovudina/uso terapêutico , Anemia/prevenção & controle , Bahamas , Canadá , Criança , Pré-Escolar , Estudos Transversais , Feminino , Infecções por HIV/tratamento farmacológico , Hemoglobinas/análise , Humanos , Lactente , Masculino , Insuficiência Renal/sangueRESUMO
OBJECTIVES: To determine the spectrum of serum immunoreactive erythropoietin (SIE) levels amongst HIV-infected children aged <13 years in relation to the levels among healthy children as well as those with renal failure; to examine the relationship between clinical and laboratory parameters and SIE levels. DESIGN: A cross-sectional study with a descriptive non-interventional format. HIV-infected Canadian subjects were recruited through four tertiary Canadian and one Bahamian centre. Children with renal failure and healthy children were recruited from one of the Canadian centres. METHODS: Study subjects had clinical and laboratory profiles determined at baseline and at each of five follow-up periods over 1 year. SIE levels were measured by radio-immunoassay with a normal range of 12-28 IU/I. Data handling and statistical functions were performed by the Canadian HIV Trials Network. RESULTS: Ths study enrolled 133 HIV-infected subjects and 38 controls. Of these, 117 HIV-infected subjects, 24 healthy controls, and 11 controls with renal failure were eligible for analysis. The median age of infected subjects was 44 months, whereas that of healthy controls was 56 months, and 95 months for controls with renal failure. The median SIE levels were 14 and 11 IU/I for subjects with renal failure and healthy subjects, respectively. The median SIE level was 61 IU/I among zidovudine (ZDV)-treated subjects and 22 IU/I among ZDV-naive HIV-infected subjects. HIV-infected children almost invariably had SIE levels < 200 IU/I. The median SIE levels amongst HIV-infected subjects whose hemoglobin levels were < 100 g/l were 98 and 31 IU/I for ZDV-treated and ZDV-naive subjects, respectively (P = 0.002). This difference in median SIE levels between ZDV-treated subjects and ZDV-naive subjects was also observed among subjects whose hemoglobin levels were > 100 g/l (median, 58 and 15 IU/I, respectively; P < 0.001). Hemoglobin level was the most important predictor of log10 SIE (P < 0.001 for ZDV-treated and ZDV-naive subjects). CONCLUSIONS: SIE levels amongst HIV-infected children were affected by HIV infection, use of ZDV, and presence or absence of anemia. SIE levels amongst HIV-infected children were generally lower than 200 IU/I. This characterization of SIE levels will facilitate clinical trials of exogenous recombinant human erythropoietin in HIV-infected children with anemia.(Au)
Assuntos
Criança , Pré-Escolar , Estudo Comparativo , Feminino , Humanos , Masculino , Lactente , Fármacos Anti-HIV/uso terapêutico , Eritropoetina/sangue , Zidovudina/uso terapêutico , Infecções por HIV/sangue , Bahamas , Canadá , Estudos Transversais , Hemoglobinas/análise , Infecções por HIV/tratamento farmacológico , Insuficiência Renal/sangue , Anemia/prevenção & controleRESUMO
The Commonwealth of the Bahamas has one of the highest rates of acquired immunodeficiency syndrome (AIDS) in the English-speaking Caribbean. A seroprevalence study of pregnant women attending antenatal clinics in New Providence in 1990-91 showed that of 3,914 pregnant women tested, 2.9% were human immunodeficiency virus (HIV) infected. Women born in the Bahamas constituted 79.2% of the women tested; 17.7% were born in Haiti. The rate of HIV infection was 2.5% in the Bahamian women as compared with 4.5% in those born in Haiti. The highest incidence was in women aged 25-34 years and in women who had multiple pregnancies. There was a significant association with a history of crack cocaine use by the Bahamian women. There was also a significant association between a lack of education and HIV infection in this group. There was a lower rate of condom use among women with less education and also among women in common-law relationships, but the association of lack of condom use and HIV infection did not reach statistical significance.
Assuntos
Infecções por HIV/epidemiologia , Complicações Infecciosas na Gravidez/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Bahamas/epidemiologia , Preservativos/estatística & dados numéricos , Cocaína Crack , Escolaridade , Feminino , Anticorpos Anti-HIV/sangue , Infecções por HIV/etiologia , Haiti/etnologia , Humanos , Incidência , Jamaica/etnologia , Abuso de Maconha/complicações , Estado Civil , Paridade , Gravidez , Complicações Infecciosas na Gravidez/etiologia , Prevalência , Fatores de Risco , Fumar/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/complicações , Sífilis/complicações , Estados Unidos/etnologiaRESUMO
The Commonwealth of the Bahamas has one of the highest rates of acquired immunodeficiency syndrome (AIDS) in the English-speaking Caribbean. A seropositive study of the pregnant women attending antenatal clinics in New Providence in 1990-91 showed that of 3,914 pregnant women tested, 2.9 percent were human immunodeficiency virus (HIV) infected. Women born in the Bahamas constituted 79.2 percent of the women tested; 17.7 percent were born in Haiti. The rate of HIV infection was 2.5 percent in the Bahamian women as compared with 4.5 percent in those born in Haiti. The highest incidence was in women aged 25-34 years and in women who had multiple pregnancies. There was a significant association with a history of crack cocaine use by the Bahamian women. There was also a significant association between a lack of education and HIV infection in this group. There was a lower rate of condom use among women with less education and also among women in common-l
Assuntos
Humanos , Feminino , Adolescente , Adulto , Gravidez , Infecções por HIV/epidemiologia , Infecções por HIV/etiologia , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/etiologia , Distribuição por Idade , Preservativos/estatística & dados numéricos , Cocaína Crack , Escolaridade , Anticorpos Anti-HIV/sangue , Incidência , Abuso de Maconha , Estado Civil , Paridade , Prevalência , Fatores de Risco , Tabagismo/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/complicações , Sífilis/complicações , Estados Unidos/etnologia , Bahamas/epidemiologia , Haiti/epidemiologia , Jamaica/etnologiaRESUMO
The objectives of the study were to determine the humoral and cellular immunological profiles of 14 patients with chronic glomerulonephritis (CGN) who were about to be dialyzed. Fourteen healthy subjects matched for age, sex and ethnic origin served as controls. Serum IgG levels showed no significant difference in the two groups. However, serum IgA levels were elevated (p<0.01) but serum IgM levels were suppressed (p<0.001). Immune complexes (IC) were prepared by the polyethylene glycol 6,000 precipitation method and their immunoglobulin content measured. The IgG and IgM levels in IC were markedly depressed (p<0.001, p<0.001 respectively. IgG subclass determinations showed that IgG1 and IgG3 were essentially the same in patients and controls. The IgG2 level, however, was markedly elevated (p<0.02) in patients. Cellular immune responses to the rheumatogenic M41 and to the nephritogenic M55 cell membrane antigens at 3 concentrations (100, 10, 1 ug/ml) as well as to phytohaemagglutinin (PHA) a non-specific mitogen, were measured. In patients, there was depressed cellular sensitivity to the M55 antigen at all 3 concentrations (p<0.01; p§.05; p<0.05, respectively). This suppression was greatly exaggerated when cellular sensitivity to the M55 antigen at the same 3 concentrations was measured (p<0.001, p<0.001, p<0.001 respectively. Patients and controls showed no difference in their response to PHA. These results suggest that both the cellular and humoral immunological factors play a role in the pathogenesis of chronic renal disease (AU)
Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Glomerulonefrite/imunologia , Fatores Sexuais , Fatores Etários , Etnicidade , Imunoglobulina G , Imunoglobulina M , Fito-Hemaglutininas , Trinidad e TobagoRESUMO
Acute rheumatic fever (ARF) has the characteristics of an autoimmune disease, triggered by cross-reactive antigens shared by the group A streptococcus and a variety of tissues including the heart, endothelium, and basal ganglia. Using two parameters of cellular reactivity, migration inhibition and blastogenic transformation, ARF patients from Trinidad show significant lymphocyte reactivity to streptococcal antigens, particularly those from an ARF associated streptococcal strain. This reactivity, studied over a 2-year period, peaked at 1 to 6 months after the acute onset and remained significantly elevated for at least 2 years. The reactivity is directed mainly toward a nonionic detergent extractable material in the cell membrane. These studies suggest a possible streptococcal strain specificity in ARF and demonstrate persistent sensitization, which explains the increased susceptibility to recurrences in the 2 years following the acute episode.
Assuntos
Antígenos de Bactérias/imunologia , Febre Reumática/imunologia , Streptococcus pyogenes/imunologia , Inibição de Migração Celular , Criança , Feminino , Glomerulonefrite/imunologia , Humanos , Imunidade Celular , Ativação Linfocitária , Masculino , Fatores de Tempo , Trinidad e TobagoRESUMO
Tetanus toxoid antibody levels were followed serially from birth to 18 months of age in 30 infants in Trinidad ranging in birth weight from 900 to 3000 grams. Antibody levels were measured by ELISA and by the mouse protection test (Connaught Laboratories, Toronto). Twelve of the 30 infants had no detectable antibodies (<0.01 units/ml) during some part of this period. In 5 of the 12 infants, there were no detectable passive antibodies (<0.01 units/ml) until after initiation of their immunization. Protective antibody levels were present following the first immunization in 4 of the 5, and following the second immunization in the fifth. These infants were susceptible to tetanus for the first 3 to 6 months of life, depending on the time of initiation of immunization. Seven infants had no detectable tetanus toxoid antibodies for periods ranging from 3 to 9 months prior to their booster at 18 months. In 5 of the 7, the passive neonatal titres at birth were high (1.5 - 12.5 units/ml). Of the 18 who had protective levels throughout this period, 15 had passive titres at birth between 0.01 and 1 units/ml. Three had passive titres of >1.5 units/ml. There was no correlation between the gestational age at birth or the time of initiation of immunization and the tetanus toxoid antibody response. Measurement of passive neonatal levels may be important in determining when an immunization programme should be initiated.
Assuntos
Humanos , Recém-Nascido , Lactente , Toxoide Tetânico/imunologia , Trinidad e TobagoRESUMO
The group G streptococcus has generally not been considered a prominent pathogen. In a 1982 study of the colonization rate by beta-haemolytic streptococci in apparently healthy children, age 5-11 years, 25 of 69 isolates belonged to group G. This surprisingly high rate of group G colonization (14.3%) led to a retrospective study of school surveys in 1967 which showed that the colonization rate with this organism was 2.3% (range 1.3-3.5%). A review of bacitracin-sensitive streptococcal isolates from hospital admissions of patients with acute glomerulonephritis (AGN), rheumatic fever, and their siblings, between January 1967 and July 1980, was conducted. Of 1063 bacitracin-sensitive isolates, 63 were group G, and 52 of these were isolated from AGN patients and their siblings, i.e. 7 from skin lesions of AGN patients, 40 from the throats of siblings and only 5 from the skins of the siblings. The other 11 group G isolates were from rheumatic-fever patients and their siblings. Thus, the group G colonization rate fluctuates in the population. The isolation of only group G streptococci from skin lesions of patients with AGN suggests a possible association between group G streptococcal pyoderma and acute post-streptococcal glomerulonephritis.
Assuntos
Glomerulonefrite/microbiologia , Streptococcus/isolamento & purificação , Doença Aguda , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Faringe/microbiologia , Pele/microbiologia , Streptococcus pyogenes/isolamento & purificação , Fatores de Tempo , Trinidad e TobagoRESUMO
During January to March, 1982, the throats of 175 apparently healthy school children, age range 5 - 11 years, were swabbed and examined for the presence of beta-haemolytic streptococci as a prerequisite to the determination of the immune response to streptococcal antigens in normal children.j There were 68 isolates comprising 39 belonging to Group A, 1 to Group B, 4 to Group C and 24 to Group G. This high rate of Group G colonisation was surprising. Subsequent examination of past record showed that of 114 throat swabs of apparently healthy school children taken in 1967, 36 yield streptococcal isolates of which 4 belonged to Group G. Of 199 cultures from skin lesions, 166 yielded streptococcal isolates of which 4 belonged to Group G but 2 of which were of mixed culture with Group A. These observations led to a review of cases of post streptococcal sequelae, acute rheumatic fever (ARF) and acute glomerulonephrotos (AGN) which occurred at the General Hospital, San Fernando, between January 1976 and July 1980 during which time all bacitracin positive streptococcal isolates from patients with post streptococcal sequelae were sent to the Public Health Laboratory, Colindale, England for grouping and typing. Of 1,073 isolates, 958 belonged to Group A, 18 to Group B, 19 to Group C, 5 to Group D and 63 to Group G. Of the 63 Group G isolates, one was isolated from the throat of a patient with ARF and 8 from siblings of ARF patients. More interestingly, there were 7 Group G isolates from skin lesions on patients with AGN and 47 from siblings of AGN patients. Though Group G streptococci have been associated with pharyngitis, neonatal sepsis and suspected gonococcal infections, this is the first report of a possible Group G associated post streptococcal acute glomerulonephritis (AU)
Assuntos
Humanos , Criança , Infecções Estreptocócicas/epidemiologia , Trinidad e Tobago , Febre Reumática , GlomerulonefriteRESUMO
The human immune system is not fully competent at the time of birth and is even more immature with earlier gestational age at delivery. Nothing is known about the ability of the immune system of the premature newborn to respond to immunization. We are studying the immune response of prematures at Mt. Hope Maternity Hospital, Trinidad to determine the optimal time of immunization. Neonates are divided into four groups based on birth weight. Each group is further subdivided into two subgroups, one immunized 6-8 weeks after birth and the other at 6-8 weeks after calculated full term. Immunization includes diphtheria, pertussis, tetanus and polio. Immune response is measured by tetanus toxoid antibody and cellular reponses. To date, 50 neonates have been entered into the study. Thirty-nine have completed the primary series of three immuniations and 27 have had at least one follow-up sample. Twelve of the neonate were less than 1500/gm at birth. Eleven of the 12 have had appropriate antibody responses. The baby who did not respond had a high titre of passive maternal antibody at birth (4.2 i.u./ml) and the absence of reponse may be related to this. No differences in reponses habe been observed with early and late immunization. Cellular responses to tetanus toxoid were variable. Forty-two per cent of babies showed in-vitro reativity to tetanus at birth. However, only 30 per cent were reactive following the primary immunization series. Responses to streptococcal antigens fluctuated with the tetanus reponses, suggesting no specificity in the blastogenic response in these neonates (AU)
Assuntos
Humanos , Recém-Nascido , Imunização , Recém-Nascido/imunologia , Recém-Nascido Prematuro/imunologia , Trinidad e Tobago , Difteria/imunologia , Coqueluche/imunologia , Poliomielite/imunologiaRESUMO
Group G streptococci were isolated from the blood of seven neonates over a five-year period at the New York Hospital. All but two were born near term. All presented clinically with signs and symptoms of neonatal sepsis. Only one case was associated with a major complication--epidermolysis bullosa; this patient died. Two presented as late-onset sepsis at 11 and 12 days of age. Six of the seven responded promptly to antibiotic therapy. A one-year survey was carried out of colonization with groups B and G streptococci at the time of discharge (day 3). Colonization with group G streptococci varied between 41 and 76% of babies each month. Group B streptococcal colonization ranged between 1 and 11%. Statistical analysis suggested that colonization with these organisms may be a mutually exclusive phenomenon.