The performance of laboratory tests in the management of a large outbreak of orally transmitted Chagas disease

Orally transmitted Chagas disease (ChD), which is a well-known entity in the Brazilian Amazon Region, was first documented in Venezuela in December 2007, when 103 people attending an urban public school in Caracas became infected by ingesting juice that was contaminated with Trypanosoma cruzi. The infection occurred 45-50 days prior to the initiation of the sampling performed in the current study. Parasitological methods were used to diagnose the first nine symptomatic patients; T. cruzi was found in all of them. However, because this outbreak was managed as a sudden emergency during Christmas time, we needed to rapidly evaluate 1,000 people at risk, so we decided to use conventional serology to detect specific IgM and IgG antibodies via ELISA as well as indirect haemagglutination, which produced positive test results for 9.1%, 11.9% and 9.9% of the individuals tested, respectively. In other more restricted patient groups, polymerase chain reaction (PCR) provided more sensitive results (80.4%) than blood cultures (16.2%) and animal inoculations (11.6%). Although the classical diagnosis of acute ChD is mainly based on parasitological findings, highly sensitive and specific serological techniques can provide rapid results during large and severe outbreaks, as described herein. The use of these serological techniques allows prompt treatment of all individuals suspected of being infected, resulting in reduced rates of morbidity and mortality.

Clinical guideline for diagnosis and management of melioidosis

Melioidosis is an emerging infection in Brazil and neighbouring South American countries. The wide range of clinical presentations include severe community-acquired pneumonia, septicaemia, central nervous system infection and less severe soft tissue infection. Diagnosis depends heavily on the clinical microbiology laboratory for culture. Burkholderia pseudomallei, the bacterial cause of melioidosis, is easily cultured from blood, sputum and other clinical samples. However, B. pseudomallei can be difficult to identify reliably, and can be confused with closely related bacteria, some of which may be dismissed as insignificant culture contaminants. Serological tests can help to support a diagnosis of melioidosis, but by themselves do not provide a definitive diagnosis. The use of a laboratory discovery pathway can help reduce the risk of missing atypical B. pseudomallei isolates. Recommended antibiotic treatment for severe infection is either intravenous Ceftazidime or Meropenem for several weeks, followed by up to 20 weeks oral treatment with a combination of trimethoprim-sulphamethoxazole and doxycycline. Consistent use of diagnostic microbiology to confirm the diagnosis, and rigorous treatment of severe infection with the correct antibiotics in two stages; acute and eradication, will contribute to a reduction in mortality from melioidosis.

American cutaneous leishmaniasis: presentation and problems of patient management

We report our experience with the diagnosis and treatment of 60 patients with American cutaneous leishmaniasis. They were infected in Panama (55), Brazil (4) or Colombia (I). Among 35 patients with a 3 week exposure in Panama, the mean maximum incubation period was 33 days (range 4-81 days). Diagnosis was delayed an average of 93 days after onset of skin lesions, due to the patient's delay in seeking medical attention (31 days), medical personnel's delay in considering the diagnosis (45 days), and the laboratory's delay in confirming the diagnosis (17 days). Forty-four patients (73%) developed ulcers typical of cutaneous leishmaniasis. Sixteen additional patients (27%) had atypical macular, papular, squamous, verrucous or acneiform skin lesions that were diagnosed only because leishmanial cultures were obtained. Of the 59 patients treated with pentavalent antimonial drugs, only 34 (58%) were cured after the first course of treatment. Lesions which were at least 2 cm in diameter, ulcerated, or caused by Leishmania braziliensis were less likely to be cured after a single course of treatment than were lesions smaller than 2 cm, nonulcerated or caused by Leishmania mexicana or Leishmania donovani.

Provision of health care actions and services for the management of HIV/AIDS from the users’ perspective

Objective To analyse the provision of health care actions and services for people living with AIDS and receiving specialised care in Ribeirão Preto, SP. Method A descriptive, exploratory, survey-type study that consisted of interviews with structured questionnaires and data analysis using descriptive statistics. Results The provision of health care actions and services is perceived as fair. For the 301 subjects, routine care provided by the reference team, laboratory tests and the availability of antiretroviral drugs, vaccines and condoms obtained satisfactory evaluations. The provision of tests for the prevention and diagnosis of comorbidities was assessed as fair, whereas the provisions of specialised care by other professionals, psychosocial support groups and medicines for the prevention of antiretroviral side effects were assessed as unsatisfactory. Conclusion Shortcomings were observed in follow-up and care management along with a predominantly biological, doctor-centred focus in which clinical control and access to antiretroviral therapy comprise the essential focus of the care provided.


Magnetic susceptibility in the prediction of soil attributes in two sugarcane harvesting management systems

This study aimed to investigate the potential use of magnetic susceptibility (MS) as pedotransfer function to predict soil attributes under two sugarcane harvesting management systems. For each area of 1 ha (one with green sugarcane mechanized harvesting and other one with burnt sugarcane manual harvesting), 126 soil samples were collected and subjected to laboratory analysis to determine soil physical, chemical and mineralogical attributes and for measuring of MS. Data were submitted to descriptive statistics by calculating the mean and coefficient of variation. In order to compare the means in the different harvesting management systems it was carried out the Tukey test at a significance level of 5%. In order to investigate the correlation of the MS with other soil properties it was made the correlation test and aiming to assess how the MS contributes to the prediction of soil complex attributes it was made the multiple linear regressions. The results demonstrate that MS showed, in both sugarcane harvesting management systems, statistical correlation with chemical, physical and mineralogical soil attributes and it also showed potential to be used as pedotransfer function to predict attributes of the studied oxisol.

Atrazine and picloram adsorption in organic horizon forest samples under laboratory conditions

Adsorption of two herbicides, atrazine and picloram, displaying different sorption characteristics, were evaluated for O (organic) horizon samples collected from SMZs (streamside management zones) in Piedmont (Ultisol) of Georgia, USA. Samples were randomly collected from within 5 SMZs selected for a study of surface flow in field trials. The five SMZs represented five different slope classes, 2, 5, 10, 15 and 20%. Results indicate that 0 horizons have the potential for sorbing atrazine from surface water moving through forested SMZs. Atrazine adsorption was nearly linear over a 24-hour period. Equilibrium adsorption, determined through 24-hour laboratory tests, resulted in a Freundlich coefficient of 67.5 for atrazine. For picloram, negative adsorption was observed in laboratory experiments. This seemed to be due to interference with ELISA analyses; however, this was not confirmed. The adsorption coefficient (Kd) obtained for atrazine in 0 horizons was greater than it would have been expected for mineral soil (from 1 to 4). Picloram was not sorbed in 0 horizons at any significant degree. Although there is a significant potential for the direct adsorption of soluble forms of herbicides in SMZs, the actual value of this adsorption for protecting water is likely to be limited even for relatively strongly sorbed chemicals, such as atrazine, due to relatively slow uptake kinetics.

Sugarcane productivity correlated with physical-chemical attributes to create soil management zone

The socioeconomic importance of sugar cane in Brazil is unquestionable because it is the raw material for the production of ethanol and sugar. The accurate spatial intervention in the management of the crop, resulting zones of soil management, increases productivity as well as its agricultural yields. The spatial and Person's correlations between sugarcane attributes and physico-chemical attributes of a Typic Tropustalf were studied in the growing season of 2009, in Suzanápolis, State of São Paulo, Brazil (20°28'10'' S lat.; 50°49'20'' W long.), in order to obtain the one that best correlates with agricultural productivity. Thus, the geostatistical grid with 120 sampling points was installed to soil and data collection in a plot of 14.6 ha with second crop sugarcane. Due to their substantial and excellent linear and spatial correlations with the productivity of the sugarcane, the population of plants and the organic matter content of the soil, by evidencing substantial correlations, linear and spatial, with the productivity of sugarcane, were indicators of management zones strongly attached to such productivity.