A global reference for caesarean section rates (C-Model): a multicountry cross-sectional study.

OBJECTIVE: To generate a global reference for caesarean section (CS) rates at health facilities. DESIGN: Cross-sectional study. SETTING: Health facilities from 43 countries. POPULATION/SAMPLE: Thirty eight thousand three hundred and twenty-four women giving birth from 22 countries for model building and 10,045,875 women giving birth from 43 countries for model testing. METHODS: We hypothesised that mathematical models could determine the relationship between clinical-obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three-step approach to generate the global benchmark of CS rates at health facilities: creation of a multi-country reference population, building mathematical models, and testing these models. MAIN OUTCOME MEASURES: Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate. RESULTS: According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C-Model, with summary estimates ranging from 0.832 to 0.844. The C-Model was able to generate expected CS rates adjusted for the case-mix of the obstetric population. We have also prepared an e-calculator to facilitate use of C-Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/). CONCLUSIONS: This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C-Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS. TWEETABLE ABSTRACT: The C-Model provides a customized benchmark for caesarean section rates in health facilities and systems.

Acute chagasic myocardiopathy after orthotopic liver transplantation with donor and recipient serologically negative for Trypanosoma cruzi: a case report.

Chagas disease (American trypanosomiasis) is caused by the protozoan parasite Trypanosoma cruzi. Chagas disease following solid-organ transplantation has occurred in Latin America. This report presents the occurrence of Chagas disease despite negative serological tests in both the donor and the recipient, as well as the effectiveness of treatment. A 21-year-old woman from the state of Sao Paulo (Brazil) underwent cadaveric donor liver transplantation in November 2005, due to cirrhosis of autoimmune etiology. Ten months after liver transplantation, she developed signs and symptoms of congestive heart failure (New York Heart Association functional class IV). The echocardiogram, which was normal preoperatively, showed dilated cardiac chambers, depressed left ventricular systolic function (ejection fraction = 35%) and moderate pulmonary hypertension. Clinical investigation discarded ischemic heart disease and autoimmune and other causes for heart failure. Immuno fluorescence (immunoglobulin M and immunoglobulin G) and hemagglutination tests for T cruzi were positive, and abundant T cruzi amastigotes were readily identified in myocardial biopsy specimens. Treatment with benznidazole for 2 months yielded an excellent clinical response. At the moment of submission, the patient remains in functional class I. This case highlighted that more appropriate screening for T cruzi infection is mandatory in potential donors and recipients of solid-organ transplants in regions where Chagas disease is prevalent. Moreover, it stressed that this diagnosis should always be considered in recipients who develop cardiac complications, since negative serological tests do not completely discard the possibility of disease transmission and since good results can be achieved with prompt trypanocidal therapy.

Study of the transdentinal diffusion of bioactive molecules.

In this work the mass transfer characteristics in a µ-tube that simulates a simplified dentinal tubule geometry are numerically investigated. The aim is to assess the key features that affect transdentinal diffusion of substances and consequently to define the necessary quantitative and qualitative issues related to a specific bioactive agent before its potential application in clinical practice. CFD simulations were performed in an S-shaped tapered micro-tube, while the code was validated using the non-intrusive optical measuring technique Laser Induced Fluorescence (LIF). As the phenomenon is one-dimensional, diffusion dominated and strongly dependent on the molecular size, the time needed for the concentration of released molecules to attain a required value can be controlled by their initial concentration. Thus, we propose a model, which is successfully verified by experimental data using a dentinal disc and which given the type of applied molecules and their critical pulpal concentration is able to estimate the initial concentration to be imposed.

Clinical characteristics of acute myocardial infarction in patients with Chagas' disease.

From 1981 to 1988, 404 patients at our institution were found to have acute myocardial infarction. Of them, 18 (4%) had a positive fixation test for Chagas' disease. Patient age ranged from 41 to 80 years (median = 59). Eleven patients were males. Eighteen nonchagasic patients were matched by 2 year age intervals and sex with each chagasic patient. Before acute myocardial infarction, there were no differences between chagasic and nonchagasic patients with regard to the proportion of stable angina, unstable angina and coronary risk factors. Atypical chest pain occurred in 8 of 15 (53%) chagasic patients for whom this information was found in the medical records and in 1 of 18 (5%) nonchagasic patients (p = 0.003); dyspnea and palpitations occurred in 6 of 15 (40%) chagasic and 1 of 17 (5%) nonchagasic patients (p = 0.025). There were no differences between chagasic and nonchagasic patients with respect to both clinical characteristics and cardiac complications of acute myocardial infarction. Nonetheless, 4 of 11 (36%) chagasic patients for whom this information was listed in the medical records but none of 16 nonchagasic patients had normal coronary arteries (p = 0.019). Thus, chagasic patients who develop acute myocardial infarction have some peculiarities both in the clinical profile before the acute event and in the anatomy of the coronary arteries.

A case of human rabies in the urban area of Ribeirã Preto, SP, Brazil.

A 39-year old male patient was admitted to the University Hospital of the Faculty of Medicine of Ribeirão, Preto with signs and symptoms of sudden dyspnea, generalized myalgia and behavioral disorders. The initial suspicion was alcohol abstinence syndrome and the patient was referred for psychiatric and neurologic care. The evolution of the patient with a worsening of signs and symptoms, presence of crises of tachypnea, agitation, difficulty to swallow, irritability and hydrophobia, and his report of having been bitten by a suspected dog raised the hypothesis of rabies. The diagnosis was confirmed by examination of a corneal impression, biological tests in the cerebrospinal fluid (CSF) and saliva and visualization of Negri bodies in nervous tissue (direct immunofluorescence). The patient evolved with agitation, aggressiveness, and worsening tachypnea intercalating with apnea, and died on the 4th day after admission.

[Serological markers of hepatitis B in users of services at an HIV Testing Center]. / Marcadores sorológicos da hepatite B em usuários de um Centro de Testagem para o HIV.

The objective of this investigation was to study the prevalence of serological markers of hepatitis B and possible risk factors for this disease in a sample of 404 people who attended a Testing and Couseling Center for HIV in the city of Ribeirão Preto, São Paulo State, Brazil. The overall prevalence of serologic hepatitis B markers was 14.6%, equal to that obtained for anti-HBc. HBsAg and anti-HBc IgM showed prevalences of 1%. After adjustment using logistic regression, hepatitis B markers showed association with the following variables: age, place of residence, use of injectable drugs and positivity to anti-HIV. The overall prevalence of human immunodeficiency virus infection was 6.9%. Hepatitis B markers were detected in 55.6% among intravenous drug users and in 42.9% among those who tested positive for HIV, confirming literature findings which indicates high levels of infection in these specific population groups.

[Survival and infectious processes in pacients with AIDS: analysis based on initial serum vitamin A levels]. / Sobrevida e processos infecciosos em pacientes com AIDS: análise de acordo com os níveis séricos iniciais de vitamina A.

Patients with Aids (n = 39) were followed up for a maximum period of 36 weeks, after which the types and topographies of infectious complications presented and patient survival were analyzed and correlated with the vitamin A levels presented by the patients at the beginning of clinical follow-up. Twenty-one (53,8%) patients presented serum retinol levels below 1.6 micromol/L, 12 (57%) of whom had values lower than 1.05 micromol/L. There was no correlation between low serum vitamin A levels and the types or topographies of the infectious complications that occurred during the follow-up period. Although mean survival at the end of the 36 months follow-up period was similar for the two groups, patients with retinol deficiency presented a lower probability of survival during the first 24 months of follow-up compared to patients without hypovitaminosis A (8.44 x 1.42 months; p = 0.003).

Dengue control in Ribeirão Preto, São Paulo, Brazil.

Following an epidemic of type I dengue in late 1990, the municipality of Ribeirão Preto (State of São Paulo, Brazil) assumed direct responsibility for the control of Aedes aegypti larvae. Control activities are presented in this report and are based on popular participation in environmental management. Massive use of the communications media, participation by schoolchildren, constant contact with the population, and integration of various public agencies are the program's priorities. Although the drop in the number of susceptibles may have played a role in the reduction of cases after the initial epidemic, the intense preventive campaign certainly helped quell the disease in the city, since changes were observed in the behavior of the population towards potential breeding sites. The occurrence of new cases in recent years appears to be related to greater circulation of the virus in both the State of São Paulo and Brazil as a whole, indicating the need for control measures at the national and continental level, without which it will be difficult to maintain low transmission rates, even in areas submitted to intense preventive work

Transformation and trends in preventive and social medicine education at the undergraduate level in a Brazilian medical school.

In the present study we discuss some transformations in undergraduate training in Preventive and Social Medicine in the Department of Social Medicine of the Faculty of Medicine of Ribeiro Preto, University of So Paulo, from 1993 to 1999. Aspects of the relationship between medical training and the reorganization of local services of the Brazilian national health system, and between graduate teaching in Preventive and Social Medicine and medical education as a whole are discussed. The crisis in Preventive and Social Medicine and its influence of medical training are evaluated. Trends for the application of a body of knowledge of the specialty and for the relationship between the department and the medical school are discussed.

[Rabies epizootic in the urban area of Ribeirão Preto, São Paulo, Brazil]. / Epizootia de raiva na área urbana de Ribeirão Preto, SP, Brasil.

This report describes some epidemiological aspects of a rabies epizootic that started in 1995 in the urban area of Ribeirão Preto, SP, Brazil, and discusses its main causes. All laboratory confirmed cases were described according to a set of epidemiological variables. Simultaneously, information was raised concerning rabies vaccine coverage and epidemiological surveillance activities. In addition to one human case, 58 rabid animals were confirmed in 1995 (54 dogs, 3 cats. and 1 bat). There were 20 cases in 1996 (18 dogs and 2 cats). Geographical distribution was uneven in the city, with higher concentrations observed in the Western, Northern, and Southwestern sections, corresponding to the poorest areas. No seasonal variation was observed. The main reasons for the epizootic were low rabies vaccine coverage in animals and severe failures in epidemiological surveillance activities in the years immediately prior to 1995. This epizootic illustrates the risk of neglecting such activities, even in a city with a reasonably good health system, located in one of the most economically developed areas of the country. Vigorous preventive measures markedly reduced the number of cases.

[Analysis of agreement between self-reported and observed information on pubertal development among school girls]. / Análise de concordância entre informações referidas e observadas acerca do estadiamento pubertário entre escolares do sexo feminino.

AIM: To test the reliability of the self-classification concerning levels of breast and public hair development among female adolescents of different socioeconomic groups. MATERIAL AND METHOD: A total of 445 female adolescents attending three secondary schools located in Ribeirão Preto, State of S. Paulo, Brazil, were studied. After being familiarised with Tanner's tables of breast and public hair development, the adolescents were asked to self classify themselves according to these variables. The results were compared to those obtained by a physical examination carried out soon after. RESULTS: Agreement rates between referred and observed information on breast development varied from 57.3% to 65.2%. For public hair the values varied from 65.4% to 73.5%. Total agreement rates for breast and public hair development, when considered simultaneously, reached values below 50.0% in the three schools. However, high agreement rates were observed for some critical degrees, such as B2, B4 and PH4. CONCLUSIONS: Significant events, such as the beginning of pubertal development, the menarche and the showing down of the body's development growth could be determined with acceptable levels of agreement. The low agreement rates observed for the simultaneous analysis of the degree of both breast and public hair show the need for the perfecting of methodologies that can replace the physical examination of adolescents, once reliable information about pubertal development is obtained in field studies.

[Availability of voluntary prenatal HIV screening in primary health centers]. / Disponibilidade de sorologia anti-HIV como um teste voluntário na rotina do atendimento pré-natal em unidades básicas de saúde.

A summary of the main steps towards the implementation of anti-HIV testing for pregnant women in the city is presented. Starting from August 1996, voluntary HIV testing became available to pregnant women seen at primary health centers in Ribeirão Preto, SP (Brazil), as part of the Prenatal Care Program. By the end of 1998, 68.3% of the 17,589 women seeking prenatal care had been tested, resulting in a positivity rate of 0.76%.

[Serological markers of hepatitis B in people submitted to blood testing in health care clinics]. / Marcadores sorológicos de hepatite B em indivíduos submetidos a exames de sangue em unidades de saúde.

OBJECTIVE: To study some of the epidemiological aspects of hepatitis B in a non-representative sample of patients seen in health care clinics. METHODS: The study population comprised 632 patients who were seen at health care clinics in the city of Ribeirão Preto, Brazil, for the purpose of blood testing, regardless the reason. After signing a written consent, an additional amount of blood was drawn from the same venous puncture site used to collect the original sample for the testing assigned to the patient at the health care clinic. A questionnaire was applied to each participant, looking for the presence of risk factors for hepatitis B. The blood samples were tested for HBV markers, using immunoenzimatic techniques. RESULTS: The prevalences of HBsAg and anti-HBcAg were 0.3% and 13.9%, respectively. By a logistic regression model, the following variables were significantly associated with the infection: age, time of residency in the city (higher risk among those living for a period less than one year), past history of hepatitis, incarceration and sexual behavior (higher risk among homosexual and bisexual males). CONCLUSIONS: The growing difficulties in obtaining blood samples from a representative group of patients, as done in classic surveys, make it necessary to look for alternative methodologies which can provide information concerning the presence of infectious agents in a community. Though the results cannot be generalized to the population as a whole, the methodology used conveyed some knowledge regarding the circulation of hepatitis B virus. In addition, it makes much easier to obtain agreement from the participants, since it does not add any invasive procedure. Despite the limitations, this methodology may be helpful in epidemiological surveillance of infectious agents known as producing asymptomatic infections in much of the population.

[Association of abreugraphic findings of the respiratory tract and clinical manifestations]. / Associação entre achados abreugráficos anômalos do aparelho respiratório e manifestações clínicas.

A retrospective study of hospital charts was conducted for the purpose of analysing the association of roent-genphotographs obtained routinely at the Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto, Brazil, since 1967, with the records of respiratory symptoms and pneumopathic diagnosis found in the medical case histories as from the patients' first clinical out-patient consultation at that hospital. For this purpose, 997 patients with abnormal pulmonary roentgenphotography findings were matched according to sex and age with the same number of controls (normal roentgenphotography). It was observed that in one third of the medical histories there was no record of any anamnesis of the respiratory system. A greater proportion of respiratory symptoms and pneumopathic diagnoses was registered in the case group. The same finding separated the patients into two groups according to the severity of the lesions. Hemoptysis and thoracic pain were the symptoms that better differentiated sick from normal patients. A selective utilization of roentgenphotography is recommended, with the method being applied only to patients presenting hemoptysis, thoracic pain and cough/expectoration, either alone or in combination.

[Influence of migration on the prevalence of serologic hepatitis B markers in a rural community. 2. Comparative analysis of various characteristics of the population studied]. / Influência da migração na prevalência de marcadores sorológicos de hepatite B em comunidade rural. 2-Análise comparativa de algumas caracteristicas das populações estudadas.

The association between prevalence of hepatitis B serological markers and birthplace, in a study carried out in a small rural county of S. Paulo State, Brazil, suggests different risk factors for hepatitis B between migrants and nonmigrant populations. These two groups were compared with regard to the following variables: level of education, professional occupation, number of previous hospitalizations, past history of blood transfusions and type of dental treatment. Migrants, mainly those from other states of Brazil, showed a low-level of education, a high proportion of people employed in agricultural activities, a higher number of past hospitalizations and higher exposure to blood transfusion and to more aggressive dental procedures. Associations were observed between the prevalence of serological markers and the following variables: level of education, professional occupation, number of previous hospitalizations and type of dental procedures, even though the last two associations did not justify the higher prevalences observed among migrants. The different distribution of hepatitis B markers seems to be dependent on the migrants' worse socio-economic condition, demonstrated by their lower level of education and by the predominance of secondary occupations.

[Influence of migration on the prevalence of serologic hepatitis B markers in a rural community. 1. Analysis of prevalence by birthplace]. / Influência da migração na prevalência de marcadores sorológicos de hepatite B em comunidade rural. 1-Análise da prevalência segundo local de nascimento.

Distribution of hepatitis B serological markers according to people's birthplaces and area of residence (urban/rural) was studied as a part of a field epidemiological research project carried out in Cássia dos Coqueiros, a small rural community of S. Paulo State, Brazil. The total prevalence of HBV markers was 7.7%, with rural showing a higher risk than urban inhabitants (9.8% as against 4.9%, respectively). Analysis of prevalence according to people's birthplaces revealed the highest value among those from other Brazilian states (15.8%), followed by people from other municipalities of the State of S. Paulo (9.2%). Those born in Cássia dos Coqueiros and particularly in Ribeirão Preto (the main city of the area, located 80 kilometers away), showed the lowest values of prevalence (5.2% and 2.5%, respectively). The importance of studying people's birthplaces when field epidemiological studies on hepatitis B are carried out is stressed. This variable is considered to be capable of exercising an influence on the natural history of the disease in a community, and may even explain differences in the distribution of markers in apparently similar populations.

[Prevalence of serological markers of hepatitis B in a small rural community of São Paulo State, Brazil]. / Prevalência de marcadores sorológicos de hepatite B numa pequena comunidade rural do Estado de São Paulo, Brasil.

Prevalence of three hepatitis B markers was measured by immunoassay techniques in small rural community of the State of S. Paulo, Brazil. Total prevalence was 7.74%, corresponding to values of 0.10%, 1.69% and 7.74% for HBsAg, anti-HBs and anti-HBc, respectively. The importance of anti-HBc determination in such studies is stressed. Comparisons between the low viral circulation observed in this area and high prevalences described in other rural communities may contribute to the raising of new hypothesis concerning alternative transmission mechanisms of hepatitis B.