It is essential to monitor the utilisation of antibacterial drugs in order to establish appropriate measures for their control. The pattern of usage of antibacterial drugs, and its association with indicators of hospital infection, has been investigated in a non-specialized adult intensive care unit (ICU) located in Santa Luzia Hospital (Brasília, DF, Brazil). The study was conducted between January 2001 and June 2004. Data concerning the utilisation of systemic antibacterial drugs, classified according to the Anatomical Therapeutic Chemical/Defined Daily Dose (ATC/DDD) system, and indicators of hospital infection, defined according to the National Nosocomial Infections Surveillance (NNIS) system, were obtained from appropriate hospital archives. During the study period, the average utilisation of antibacterial drugs was 1918.5 DDD units per 1000 patient-day (DDD1000). The three most used drugs were penicillins/beta-lactamase inhibitors (535.3 DDD1000), third generation cephalosporins (239.1 DDD1000) and quinolones (212.5 DDD1000). The total utilisation of antibacterial drugs was correlated significantly with the incidence of hospital infection (R = 0.62; p < 0.01) and the index of invasive procedures (R = 0.41; p < 0.01). Furthermore, the latter two indicators were significantly and positively correlated with the use of recently commercialised, broad spectrum antibacterial drugs (except for carbapenems). It is concluded that improved infection control procedures, together with more rigorous criteria regarding the use of invasive procedures, should be implemented by the ICU studied in order to diminish the utilisation of antibacterial drugs.

Usamos um método molecular e demonstramos que o tratamento de infecções crônicas pelo Trypanosoma cruzi com nitroderivados, que se mostraram eficientes em diminuir parasitemias nas infecções agudas, não produziu cura parasitológica. Trinta e quatro chagásicos crônicos, com pelo menos dois entre três testes sorológicos positivos para a infecção, e 17 controles com testes sorológicos negativos formaram os grupos de estudo. Os testes de PCR com primers de DNA de T. cruzi monitoraram a eficácia do tratamento. Foram obtidos produtos de PCR a partir de DNA de pacientes chagásicos tratados e não-tratados, com primers de DNA nuclear de T. cruzi. Os produtos amplificados hibridizaram com suas sequências internas e complementares. A técnica de PCR competitiva foi usada para quantificar o número de parasitos no sangue e revelou < 1 a 75 T. cruzi/ml em chagásicos não-tratados (média 25,83 ± 26,32) e < 1 a 36 T. cruzi/ml em chagásicos tratados (média 6,45 ± 9,28). A diferença entre as médias não foi estatisticamente significativa. O resultado mostra que o tratamento da doença de Chagas crônica com drogas nitroderivadas é insatisfatório.

We used a molecular method and demonstrated that treatment of the chronic human Trypanosoma cruzi infections with nitroderivatives did not lead to parasitological cure. Seventeen treated and 17 untreated chronic Chagas' disease patients, with at least two out of three positive serologic assays for the infection, and 17 control subjects formed the study groups. PCR assays with nested sets of T. cruzi DNA primers monitored the efficacy of treatment. The amplification products were hybridized to their complementary internal sequences. Untreated and treated Chagas' disease patients yielded PCR amplification products with T. cruzi nuclear DNA primers. Competitive PCR was conducted to determine the quantity of parasites in the blood and revealed < 1 to 75 T. cruzi/ml in untreated (means 25.83 ± 26.32) and < 1 to 36 T. cruzi/ml in treated (means 6.45 ± 9.28) Chagas' disease patients. The difference between the means was not statistically significant. These findings reveal a need for precise definition of the role of treatment of chronic Chagas' disease patients with nitrofuran and nitroimidazole compounds.

Neste estudo, foram obtidos estoques de Trypanosoma cruzi de pacientes chagásicos com a doença cardíaca ou com megaesôfago. O estoque hSLU239 (doença cardíaca) forneceu os clones h1 e h2, enquanto o estoque mSLU142 (megaesôfago) forneceu os clones m1, m2, m3 e m4. A cinética de crescimento do parasito, tempo de duplicação e diferenciação em meio líquido axênico mostraram ampla diversidade comportamental. Observou-se que um padrão particular de comportamento de um estoque parental podia não ser necessariamente encontrado na linhagem subclonal subseqüente. Este estudo indica que i) cada paciente chagásico é infectado com várias subpopulações de T. cruzi; ii) linhagens clonais derivadas de cada estoque do parasito podem ter características biológicas diferentes do isolado original de paciente chagásico; e que iii) marcadores comportamentais e/ou moleculares adicionais são necessários para melhor caracterização de estoques de T. cruzi e seus clones derivados de pacientes com doença de Chagas, a fim de identificar as possíveis correlações com a patologia.

In this study, we isolated Trypanosoma cruzi from chronic Chagas heart disease and from megaesophagus patients. The parasite stock hSLU239 (heart disease) yielded clones h1 and h2, whereas stock mSLU142 (megaesophagus) yielded clones m1, m2, m3 and m4. The parasite growth kinetics, doubling time and differentiation in axenic liquid medium showed broad behavioral diversity. It was shown that a particular pattern of behavior for a parental stock could not necessarily be assigned for subsequent clones. This study indicates that i) each Chagas disease patient is infected with several T. cruzi populations; ii) clonal lines derived from patient samples may have different biological characteristics from the original isolate; and that iii) additional behavioral and/or molecular markers are required for further characterization of Trypanosoma cruzi stocks and clones derived from Chagas disease patients in order to identify correlations with pathology.

A prevalência da infecção chagásica em 368 garis do Serviço de Limpeza Urbana (SLU) do Distrito Federal foi inicialmente indicada pelos exames de hemaglutinação e imunofluorescência, quando encontrou-se 32,1% e 47,6% de resultados positivos, respectivamente, para cada exame. Em vista das discrepâncias obsevadas. utilizou-se o teste cutâneo com o antígeno T12E para esclarecimento do diagnóstico em 15,5% dos que tinham apenas um teste sorológico positivo. O teste cutâneo foi positivo em 38,6% dos garis. A análise dos resultados de 183 garis mostrou 47% dos casos com três exames concordantes positivos. Mais 19, 7% tiveram dois exames concordantes positivos. Porém, 33,3% dos garis tinham apenas um dos três exames positivo. Empregou-se também o "immunoblot" na tentativa de esclarecer o diagnóstico nos 61 casos com apenas um resultado positivo. Foram encontrados 37,5% (3/8) dos casos positivos pela hemaglutinação, 11,5% (3/26) pelo teste cutâneo, e apenas 3,7% (1/27) pela imunofluorescência. Após a adição desses casos positivos pelo "immunoblot", o total de chagásicos passou a ser de 129, ou seja, 35%/ dos garis da amostra estudada.

Seropositivity for Trypanosoma cruzi infection was studied in 308 street-sweepers of the SLU. Federal District. Brazil, with the aid of haemaglutination. immunofluorescence and, also, a delayed-type skin test to the parasite T12E antigen. It showed 32,1%, 42.7% and 38.6% positive results, respectively for cach assay. Among these, however, only 47% were positive with each of three exams performed. In addition, 19.7% were positive with two out of three exams performed. The remaining 33-3% sera yielded one positive result out of three exams employed and were submitted to the immunoblot assay. This analysis confirmed 3 cases (37.5%) positive by hemmaglutination. 3 (11.5%) positive by skin test, and 1 (3-7%) positive by immunofluorescence. At the end of the analysis, it was shown that 129 (35%) individuals yielded at least two positive assays and therefore, they should be cousidered as T. cruzi-infected individuals.