Urinary iron excretion induced by intravenous infusion of deferoxamine in beta-thalassemia homozygous patients.

The purpose of the present study was to identify noninvasive methods to evaluate the severity of iron overload in transfusion-dependent beta-thalassemia and the efficiency of intensive intravenous therapy as an additional tool for the treatment of iron-overloaded patients. Iron overload was evaluated for 26 beta-thalassemia homozygous patients, and 14 of them were submitted to intensive chelation therapy with high doses of intravenous deferoxamine (DF). Patients were classified into six groups of increasing clinical severity and were divided into compliant and non-compliant patients depending on their adherence to chronic chelation treatment. Several methods were used as indicators of iron overload. Total gain of transfusion iron, plasma ferritin, and urinary iron excretion in response to 20 to 60 mg/day subcutaneous DF for 8 to 12 h daily are useful to identify iron overload; however, urinary iron excretion in response to 9 g intravenous DF over 24 h and the increase of urinary iron excretion induced by high doses of the chelator are more reliable to identify different degrees of iron overload because of their correlation with the clinical grades of secondary hemochromatosis and the significant differences observed between the groups of compliant and non-compliant patients. Finally, the use of 3-9 g intravenous DF for 6-12 days led to a urinary iron excretion corresponding to 4.1 to 22.4% of the annual transfusion iron gain. Therefore, continuous intravenous DF at high doses may be an additional treatment for these patients, as a complement to the regular subcutaneous infusion at home, but requires individual planning and close monitoring of adverse reactions.

Urinary iron excretion induced by intravenous infusion of deferoxamine in ß-thalassemia homozygous patients

The purpose of the present study was to identify noninvasive methods to evaluate the severity of iron overload in transfusion-dependent ß-thalassemia and the efficiency of intensive intravenous therapy as an additional tool for the treatment of iron-overloaded patients. Iron overload was evaluated for 26 ß-thalassemia homozygous patients, and 14 of them were submitted to intensive chelation therapy with high doses of intravenous deferoxamine (DF). Patients were classified into six groups of increasing clinical severity and were divided into compliant and non-compliant patients depending on their adherence to chronic chelation treatment. Several methods were used as indicators of iron overload. Total gain of transfusion iron, plasma ferritin, and urinary iron excretion in response to 20 to 60 mg/day subcutaneous DF for 8 to 12 h daily are useful to identify iron overload; however, urinary iron excretion in response to 9 g intravenous DF over 24 h and the increase of urinary iron excretion induced by high doses of the chelator are more reliable to identify different degrees of iron overload because of their correlation with the clinical grades of secondary hemochromatosis and the significant differences observed between the groups of compliant and non-compliant patients. Finally, the use of 3-9 g intravenous DF for 6-12 days led to a urinary iron excretion corresponding to 4.1 to 22.4 percent of the annual transfusion iron gain. Therefore, continuous intravenous DF at high doses may be an additional treatment for these patients, as a complement to the regular subcutaneous infusion at home, but requires individual planning and close monitoring of adverse reactions

Acute myocardial infarction in the Brazilian State of São Paulo. In-hospital deaths from 1979 to 1996 and hospital fatality from 1984 to 1998 in the public health system.

OBJECTIVE: To determine the following parameters in the Brazilian State of São Paulo: 1) the percentage of deaths due to acute myocardial infarction (AMI) occurring in hospitals; 2) the percentage of deaths due to AMI occurring in public health system hospitals as compared with all in-hospital deaths due to AMI between 1979 and 1996; 3) the fatality due to AMI in public health system hospitals from 1984 to 1998. METHODS: Data were available on the Datasus Web site (the health information agency of the Brazilian Department of Health) that provided the following: a) number of deaths resulting from AMI in hospitals; b) number of deaths resulting from AMI in public health system hospitals; c) number of hospital admissions due to AMI in public health system hospitals. RESULTS: The percentage of in-hospital deaths due to AMI increased from 54.9 in 1979 to 68.6 in 1996. The percentage contribution of the public health system to total number of deaths due to AMI occurring in hospitals decreased from 22.9 in 1984 to 13.7 in 1996; fatality due to AMI occurring in public health system hospitals had an irregular evolution from 1984 to 1992 and showed a slight trend for increased frequency from 1993 to 1998. CONCLUSION: The percentage of in-hospital deaths due to AMI has been increasing. Deaths resulting from AMI in public health system hospitals have decreased when compared with the total number of deaths due to AMI in all hospitals. Fatality due to AMI in public health system hospitals did not decrease from 1992 to 1998.

Sequential randomised and double blind trial of promethazine prophylaxis against early anaphylactic reactions to antivenom for bothrops snake bites.

OBJECTIVE: To investigate the efficacy of the H1 antihistamine promethazine against early anaphylactic reactions to antivenom. DESIGN: Sequential randomised, double blind, placebo controlled trial. SETTING: Public hospital in a venom research institute, São Paulo, Brazil. PARTICIPANTS: 101 patients requiring antivenom treatment after being bitten by bothrops snakes. INTERVENTION: Intramuscular injection of promethazine (25 mg for adults and 0.5/kg for children) or placebo given 15-20 min before starting intravenous infusion of antivenom. MAIN OUTCOME MEASURES: Incidence and severity of anaphylactic reactions occurring within 24 hours after antivenom. RESULTS: Reactions occurred in 12 of 49 patients treated with promethazine (24%) and in 13 of 52 given placebo (25%); most were mild or moderate. Continuous sequential analysis indicated that the study could be interrupted at the 22nd untied pair, without preference for promethazine or placebo. CONCLUSION: Prophylaxis with promethazine does not prevent early reactions. Patients should be observed carefully during antivenom infusion and the subsequent few hours.

A method for calculating age-weighted death proportions for comparison purposes.

OBJECTIVE: To introduce a method for calculating age-weighted death proportions (wDP) for comparison purposes. MATERIALS AND METHODS: A methodological study using secondary data from the municipality of São Paulo, Brazil (1980-1994) was carried out. First, deaths are weighted in terms of years of potential life lost before the age of 100 years. Then, in order to eliminate distortion of comparisons among proportions of years of potential life lost before the age of 100 years (pYPLL-100), the denominator is set to that of a standard age distribution of deaths for all causes. Conventional death proportions (DP), pYPLL-100, and wDP were calculated. RESULTS: Populations in which deaths from a particular cause occur at older ages exhibit lower wDP than those in which deaths occur at younger ages. The sum of all cause-specific wDP equals one only when the test population has exactly the same age distribution of deaths for all causes as that of the standard population. CONCLUSION: Age-weighted death proportions improve the information given by conventional DP, and are strongly recommended for comparison purposes.

Roll-over test in primigravidae attending a public primary care service.

OBJECTIVE: To determine the roll-over test (ROT) performance in predicting pregnancy-induced hypertension (PIH) in primigravidae aged 15-29 years in a public primary care service. METHOD: Prospective cohort study enrolling 369 consecutive and initially normotensive primigravidae. The ROT was applied within 28-32 weeks of pregnancy. PIH was defined as diastolic blood pressure (DBP) 90 mm Hg or systolic blood pressure (SBP) 140 mm Hg, or a rise in DBP 15 mm Hg or a rise in SBP 30 mm Hg. The ROT prognostic properties were calculated, and a receiver operating characteristic (ROC) curve was constructed. RESULTS: For the 20 mm Hg cutoff point, sensitivity was 20% and specificity was 93%. Positive and negative predictive values were, respectively, 23% and 92%, for a PIH cumulative incidence of 9.5%. With other cutoff points, the ROC curve showed a poor discriminatory value of the test. CONCLUSION: The ROT was not useful for predicting PIH in a primary prenatal care setting.

[Perinatal deaths in the city of Fortaleza: how many deaths could be prevented?]. / Mortes perinatais no município de Fortaleza, Ceará: o quanto é possível evitar?

OBJECTIVE: The main objective of this study was to explore the relationship between perinatal care and neonatal mortality as a component of the infant mortality. Indicators were selected to analyze some aspects of the quality of perinatal care attendance offered to pregnant women and their newborns. Specific attention was given to the avoidable perinatal deaths in the city of Fortaleza, Ceará. METHODS: Population-based, prospective study on incidence. The study was carried out collecting data of seventeen maternity units and two referral pediatric hospitals of the public health system in Fortaleza, the capital of the State of Ceará. All births, alive or dead, weighting 500 grams or more, along the whole year of 1995, were included in the study. The perinatal deaths' causes were studied according to the modified Wigglesworth classification (1989). RESULTS: Along the whole study period, 40,712 children were born and 1,337 perinatal deaths occurred. Among them 730 occurred during the fetal life and 607 during the first week of life. In spite of the low incidence of low-weight newborns (7.4%), the coefficients of fetal mortality were high (17.9 per thousand), as well as the perinatal mortality (32.8 per thousand) and neonatal mortality (15.1 per thousand). The number of avoidable perinatal deaths related to adequate perinatal care was estimated to be one third of the total deaths studied (458/1,323). CONCLUSIONS: The results indicate that the perinatal assistance in the city of Fortaleza is of low quality, with problems related to the health system organization and to the low quality of the care offered to women during pregnancy, at delivery and to the newborns in the delivery room as well as in neonatal wards.

Proinsulin and insulin levels according to glucose tolerance among Japanese-Brazilians, aged 40-79 years. Japanese-Brazilian Diabetes Study Group.

This study of the Japanese-Brazilians living in Bauru, Sao Paulo, Brazil, aimed at determining the prevalence of DM in the first (Issei) and second (Nisei) generations, according to WHO criteria. Insulin and proinsulin were determined by new immunofluorimetric assays (IMFA), that measure true insulin and intact proinsulin, at fasting and 2 h after glucose load. The data showed a very scattered distribution, so only medians are shown and no statistical testing applied. There was a tendency for higher proinsulin levels in the diabetic groups. The highest fasting proinsulin levels were seen in the diabetic patients, either obese or non-obese. The post-load insulin levels were higher in diabetic and IGT individuals, compared to normals. Both generations showed a distinct behaviour for the obese and non-obese groups, and no major differences were observed between generations. This population seems to be sensitive to environmental changes, since the obese groups showed the higher levels of proinsulin and insulin. In the evaluation of the role of the environmental factors in the pathogenesis of DM, proinsulin and insulin levels could act as early markers of pancreatic dysfunctions.

[Prevalence of serologic markers of hepatitis B and D viruses in children of the Caiabi and Txucarramãe tribes from the Indian Reservation of Xingu, central Brazil]. / Prevalência dos marcadores sorológicos dos vírus da hepatite B e D em crianças das tribos Caiabi e Txucarramãe do Parque Indígena do Xingu, Brasil central.

The medical literature has shown that the inhabitants of the Amazon region are highly affected by hepatitis B and delta viruses infection, but this has never been studied in Indian children by age group. A study of the prevalence of serological markers of hepatitis B and delta viruses in Indian children aged 0 to 14 years living in the PIX was carried out. This Park is located in Central Brazil, a region which is in the transition between the savannab to the south and the Amazon jungle to the north. To determine the prevalence of HBV and HDV markers in Indian children and to characterize the route of HBV transmission in this region. Out of the 17 tribes living in the PIX, two--the Caiabi and the Txucarramãe--were chosen because both live in the North part of the Park, but have quite different ways of life. The overall prevalence of HBV serum markers was: HBsAg, 4.5%; anti-HBs, 39.6%; anti-HBc, 44.1%; any marker of HBV, 47.3%; and anti-HDV, 0.0%. However, a striking difference in the prevalence of hepatitis B markers was observed between the two tribes: younger Caiabi children were much less affected than the Txucarramãe ones. The prevalence of HBsAg in fertile women was 12%, being anti-HBe positive. Our data suggest that HBV infection is highly prevalent among Indian children living in this Indigenous Park and vertical infection is not an important route of transmission in either tribes.

Blood pressure in four remote populations in the INTERSALT Study.

Four remote population samples (Yanomamo and Xingu Indians of Brazil and rural populations in Kenya and Papua New Guinea) had the lowest average blood pressures among all 52 populations studied in INTERSALT, an international cooperative investigation of electrolytes and blood pressure. Average systolic blood pressure was 103 versus 120 mm Hg in the remaining INTERSALT centers; diastolic blood pressure in these four population samples averaged 63 versus 74 mm Hg in the 48 other centers. There was little or no upward slope of blood pressure with age; hypertension was present in only 5% of the rural Kenyan sample and virtually absent in the other three centers. Also in marked contrast with the rest of the centers was level of daily salt intake, as estimated by 24-hour urinary sodium excretion. Median salt intake ranged from under 1 g to 3 g daily versus more than 9 g in the rest of INTERSALT populations. Average body weight was also low in these four centers, with no or low average alcohol intake, again unlike the other centers. The association within these four centers between the above variables and blood pressure was low, possibly reflecting their limited variability. While several other INTERSALT centers also had low average body weight or low prevalence of alcohol drinking, when this was accompanied by much higher salt intake (7-12 g salt or 120-210 mmol sodium daily), hypertension prevalence ranged from 8% to 19%. These findings confirm previous reports that in populations with a low salt intake, there is little or no hypertension or rise of blood pressure with age.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of antibody against influenza A viruses in the Kren-Akorore, an Indian tribe of Central Brazil, first contacted in 1973.

Influenza A antibodies in serum samples obtained in 1980 from two Indian populations in Central Brazil were compared. The Kren-Akorore, who were first contacted in 1973 and two years later transferred to the Xingu Indian Park (PIX), were compared with Indians from other tribes already living in the PIX before 1975. An analysis was made of the prevalence and distribution of antibodies against the influenza A viruses which have circulated in the civilized world since 1918. Antibodies to the early influenza A viruses were absent in both Indian populations, but A/Hong Kong/1/68 (H3N2) virus apparently circulated in the PIX. No antibody to influenza A/Bangkok/1/79 or to A/Brazil/11/78 (H1N1) was found in any of the sera, whereas antibodies to these viruses were commonly found in urban populations in Brazil. The evidence from influenza antibodies agrees with the information that the Kren-Akorore Indians had been living in complete isolation until 1973, when they were first contacted.

A interpretacao de testes diagnosticos. / The interpretation of diagnostic tests

Numero consideravel de publicacoes sobre interpretacao de testes diagnosticos tem sido publicado nos ultimos anos. O leitor medico e facilmente afogado por graficos, tabelas, curvas, formulas e jargao tecnico Neste artigo, os autores enfocam o tema, apresentando estrategias e taticas para interpretacao de testes diagnosticos, apresentados de maneira didatica e de facil manuseio pelo clinico. Apesar de a maioria das explicacoes de como interpretar um teste diagnostico usar exemplos de resultados de laboratorio, os mesmos principios aplicam-se igualmente para achados de historia ou exame fisico. Os autores pretendem, atraves da discussao de um teste diagnostico - dosagem de CPK para diagnostico de infarto do miocardio - apresentar uma sistematica para interpretacao de um teste diagnostico em geral, usando o minimo possivel de conceitos matematicos e utilizando sempre exemplos de situacoes clinicas rotineiras

Criterios metodologicos para escolha de procedimentos terapeuticos. / Methodological criteria for the choise of therapeutic procedures

Com certo atraso com relacao as ciencias sociais, a literatura medica da ultima decada foi marcada por relevante melhora no padrao metodologico de seus artigos. Consequentemente, a discussao de achados de pesquisas na area de saude incorporou todo um jargao metodologico ate entao muito pouco conhecido pelo profissional de saude. A interpretacao dos resultados de uma investigacao cientifica passa necessariamente pelo crivo de cuidadosa analise metodoligica. Ou seja, antes de aceitar as conclusoes a que chegou o investigador, o leitor medico passa a se questionar quanto a qualidade metodologica empregada na investigacao. Nesse artigo os autores discutem, de maneira didatica, criterios falcilmente manuseaveis pelo clinico, para avaliacao da qualidade da informacao sobre procedimentos terapeutios em geral. Em outros artigos, discutiremos criterios na determinacao da qualidade da informacao sobre testes diagnosticos, prognosticos e associacoes casuais/