Botulismo bovino: comprovação laboratorial do diagnóstico clínico, período 1986-1989

Num período de 4 anos (1986-1989) foram processados 517 materiais correspodentes a 235 casos com diagnóstico clínico de botulismo de bovinos, dos Estados de São Paulo, Mato Grosso, Mato Grosso do Sul, Minas Gerais, Goiás, Bahia, Pará, Maranhão, Distrito Federal e Roraima (Brasil). Exames laboratoriais foram realizados com o intuito de confirmar a suspeita clínica, detectando a toxina nos materiais correspondentes aos casos supracitados. Os tipos de toxina verificados foram "C" e "D" presentes no fígado e conteúdos de estômago e intestinos, que perfaziam o maior número das amostras remetidas. O pequeno número de casos confirmados leva à suposição de que outras enfermidades devem estar envolvidas nessas mortes, ainda que se considere possíveis resultados falso negativos.

Diagnóstico laboratorial de raiva em quirópteros realizado em área metropolitana na região sudeste do Brasil

No período de janeiro de 1988 adezembro de 1992, foi realizado diagnóstico de raiva em 289 morcegos através das técnicas de imunofluorescência direta e de inoculação intracerebral em camundongos. Dois morcegos insetívoros da espécie Nyctinomops macrotis se apresentaram positivos, representando 0,69% da amostra. Esses morcegos foram capturados, ainda vivos, em 1988 e 1990, na sala de um apartamento no sétimo andar e no muro de uma casa, respectivamente. Ambos em bairros residenciais. Apresentaram período de incubação de 13 e 11 dias, respectivamente, na prova biológica. A existência de morcegos insetívoros infectados com o vírus da raiva é preocupante, uma vez que essa população parece ser cada vez mais freqüente em áreas urbanas, porém isto não justifica ações predatórias indiscriminadas contra as espécies, principalmente levando-se em consideração a importância do morcego no equilíbrio ecológico da população de insetos, abundante em área urbana.

Estudo sobre o diagnóstico laboratorial e sintomas do dengue, durante epidemia ocorrida na região de Ribeirão Preto, SP, Brasil

Uma epidemia de dengue tipo 1 se iniciou em Novembro de 1990 na Região de Ribeirão Preto, Norte do Estado de São Paulo. Foram confirmados por exames laboratoriais cerca de 3.500 casos até fevereiro de 1991. A Unidade de Pesquisa em Virologia da Faculdade de Medicina de Ribeirão Preto - USP, estudou soros de 502 pessoas suspeitas de apresentarem dengue. Fez-se o diagnóstico sorológico através do método da inibição da hemaglutinação (HAI) para dengue tipo 1 em 19% dos analisados. Passou-se a utlilizar um teste imuno-enzimático para dengue em culturas celulares infectadas (EIA-ICC), que permite identificação simultânea de IgG e IgM. O EIA-ICC embora menos sensível quando comparado ao HAI (89%), mostrou-se mais eficiente, porque: dispensou a obtenção de segundas amostras séricas para o diagnóstico; trata-se de técnica simples, podendo ser efetuada em apenas 5 horas. O vírus dengue tipo 1 foi isolado do sangue de 21 pacientes, por inoculação em células de mosquitos C6/36. Fez-se a identificação dos vírus isolados por método de imunofluorescência indireta, utilizando anti-soro contra todos os flavivirus e anticorpos monoclonais tipo-específicos de dengue. Os sintomas mais freqüentemente observados em 71 indivíduos com diagnóstico de dengue confirmado foram febre (90% dos casos), mialgias (57%) e artralgias (41%)

Clinical and laboratorial features of visceral toxocariasis in infancy

Forty children with a diagnosis of Visceral Toxocariasis were evaluated prospectively from February 1982 to June 1989. Diagnosis was established by clinical, laboratorial and serological (ELISA - ES Toxocara canis antigen) evaluations. A great clinical polymorphism was found in our patients, ranging from unspecific or absent manifestations to an exhuberant symptomatology. The laboratorial findings were: leukocytosis,eosinophilia and elevation of serum gammaglobulin and isohemagglutinin levels. No significant relationship between clinical findings and laboratorial parameters was found. Serology (ELISA) was a method of great diagnostic support but did not show a correlation with clinical and laboratorial findings in this study. There was a significant relationship between pulmonary manifestations and the presence of signs and/or symptoms, when the patients were sent to us. Our findings, especially the high incidence of pulmonary manifestations, suggest that Visceral Toxocariasis has to be included in the differential diagnostic of children with pulmonary manifestations, characteristic epidemiological data and associated eosinophilia.

Jungle yellow fever: clinical and laboratorial sudies emphasizing viremia on a human case

The authors report the clinical, laboratorial and epidemiological aspects of a human case of jungle yellow fever. The patient suffered from fever, chills, sweating, headaches, backaches, myalgia, epigastric pains, nausea, vomiting, diarrhea and prostration. He was unvaccinated and had been working in areas where cases of jungle yellow fever had been confirmed. Investigations concerning the yellow fever virus were performed. Blood samples were collected on several days in the course of the illness. Three of these samples (those obtained on days 5,7 and 10) were inoculated into suckling mice in attempt to isolate virus and to titrate the viremia level. Serological surveys were carried out by using the IgM Antibodies Capture Enzyme Linked Immunosorbent Assay (MAC-ELISA), Complement Fixation (CF), Hemagglulinalion Inhibition (HI) and Neutralization (N) tests. The yellow fever virus, recovered from the two first samples and the virus titration, showed high level of viremia. After that, specific antibodies appeared in all samples. The interval between the end of the viremia and the appearance of the antibodies was associated with the worsening of clinical symptoms, including bleeding of the mucous membrane. One must be aware of the risk of having a urban epidemics in areas where Aedes aegypti is found in high infestation indexes.

Dengue type 2 outbreak in the south of the State of Bahia, Brazil: laboratorial and epidemiological studies

During March 1994 cases of a exanthematic acute disease were reported in the municipalities of Itagemirim, Eunápolis and Belmonte, state of Bahia. Dengue fever was confirmed by serology (MAC-ELISA) and by dengue virus type 2 isolation, genotype Jamaica. Signs and symptoms of classic dengue fever were observed with a high percentual of rash (73.8%) and pruritus (50.5%). Major haemorrhagic manifestations were unfrequent and only bleeding gum was reported. Dengue virus activity spreaded rapidly to important tourism counties like Porto Seguro, Ilhéus, Santa Cruz de Cabrália, Prado, Alcobaça and others, representing a risk for the spreading of dengue virus into the country and abroad.

A clinical, epidemological, laboratorial, histological and ultrasonographical evaluation of anti-HCV EIA-2 positive blood donors

Between 1992 and 1997, 790 blood donors with anti-HCV EIA-2 strongly reagent (relationship between the sample optical density/cut-off > 3) detected at the blood bank serological screening, were evaluated in ambulatory environment. They were all negative for Chagas disease, syphilis, hepatitis B (HBsAg) and AIDS. Blood samples were collected at the first ambulatorial evaluation, for hemogram, biochemical tests and new serological tests for HCV (anti-HCV EIA-2). In blood samples of 226 repeatedly reagent anti-HCV EIA-2 blood donors, supplementary "immunoblot" test for HCV (RIBA-2) was used. In 209 donors, the presence of HCV-RNA was investigated by the PCR test. The abdominal ultrasonography was realized in 366 donors. In 269 patients liver biopsy was performed for the histopathological study. The follow-up of blood donors showed that 95.6% were repeatedly EIA-2 reagent, 94% were symptomless and denied any hepatitis history, with only 2% mentioning previous jaundice. In 47% of this population at least one risk factor has been detected for the HCV transmission, the use of intravenous drugs being the main one (27.8%). Blood transfusion was the second factor for HCV transmission (27.2%). Hepatomegaly was detected in 54% of the cases. Splenomegaly and signs of portal hypertension have seldom been found in the physical examination, indicating a low degree of hepatic compromising in HCV. Abdominal ultrasound showed alterations in 65% of the subjects, being the steatosis the most frequent (50%). In 83.5% of the donors submitted to the liver biopsy, the histopathological exam showed the presence of chronic hepatitis, usually classified as active (89%) with mild or moderate grade in most of the cases (99.5%). The histopathological exam of the liver was normal in 1.5% of blood donors. The RIBA-2 test and the HCV-RNA investigation by PCR were positive in respectively 91.6 and 75% of the anti-HCV EIA-2 reagent donors. The HCV-RNA research was positive in 82% of the RIBA-2 positive subjects, in 37.5% of the indeterminate RIBA-2 donors and in 9% of the negative RIBA-2 donors. Chronic hepatitis has also been observed in 50% of the histopathological exams of the anti-HCV EIA-2 reagent donors which were indeterminate RIBA-2. Among 18 blood donors with minimal changes histopathological exam 11 (61%) were HCV-RNA positive. Our blood donors anti-HCV reagent generally had clinical, laboratorial and histopathological features observed in patients with chronic HCV hepatitis and a high proportion could be identified in interviews and medical evaluation realized in blood blanks. Generally, these HCV infected donors are identified and discharged only by the serological tests results.

Botulism in Brazil, 2000-2008: epidemiology, clinical findings and laboratorial diagnosis

Botulism is a rare and potentially lethal illness caused by Clostridium botulinum neurotoxin. We describe the findings of a laboratorial investigation of 117 suspected cases of botulism reported to the surveillance system in Brazil from January 2000 to October 2008. Data on the number and type of samples analyzed, type of toxins identified, reporting of the number of botulism cases and transmission sources are discussed. A total of 193 clinical samples and 81 food samples were analyzed for detection and identification of the botulism neurotoxin. Among the clinical samples, 22 (11.4%) presented the toxin (nine type A, five type AB and eight with an unidentified type); in food samples, eight (9.9%) were positive for the toxin (five type A, one type AB and two with an unidentified type). Of the 38 cases of suspected botulism in Brazil, 27 were confirmed by a mouse bioassay. Laboratorial botulism diagnosis is an important procedure to elucidate cases, especially food-borne botulism, to confirm clinical diagnosis and to identify toxins in food, helping sanitary control measures.

SUSCEPTIBILITY TEST FOR FUNGI: CLINICAL AND LABORATORIAL CORRELATIONS IN MEDICAL MYCOLOGY

SUMMARYDuring recent decades, antifungal susceptibility testing has become standardized and nowadays has the same role of the antibacterial susceptibility testing in microbiology laboratories. American and European standards have been developed, as well as equivalent commercial systems which are more appropriate for clinical laboratories. The detection of resistant strains by means of these systems has allowed the study and understanding of the molecular basis and the mechanisms of resistance of fungal species to antifungal agents. In addition, many studies on the correlation of in vitro results with the outcome of patients have been performed, reaching the conclusion that infections caused by resistant strains have worse outcome than those caused by susceptible fungal isolates. These studies have allowed the development of interpretative breakpoints for Candida spp. and Aspergillus spp., the most frequent agents of fungal infections in the world. In summary, antifungal susceptibility tests have become essential tools to guide the treatment of fungal diseases, to know the local and global disease epidemiology, and to identify resistance to antifungals.

Ensaio laboratorial e clínico com Hycanthone, nôvo agente esquistossomicida

A partir do Miracil D, um derivado hidroximetílico (Hycanthone) pode ser obtido através da atividade biológica do Aspergillus sclerotiorum. Êste derivado mostrou-se muito ativo quando administrado a camundongos, hamsters e macacos Cebus experimentalmente infectados com Schistosoma mansoni. Ensaios clínicos com o Hycanthone foram feitos em 52 pacientes com esquistossomose mansoni ativa. A droga foi administrada, nas doses de 2 e 3 mg/kg/ dia, junto com um anti-ácido, duas vêzes ao dia, durante 5 dias consecutivos. Com exceção de 2 casos, todos os pacientes completaram o tratamento. Náusea e/ou vômito, anorexia, tonturas e cefaléia foram os efeitos colaterais mais comuns. Atividade terapêutica foi avaliada através de repetidos exames de fezes (4 a 6) e uma biópsia retal realizada a partir do 4.° mês após o tratamento. As percentagens de cura foram de 83,3 e 80,0% com o esquema de 2 e 3 mg/kg, respectivamente. Os dados laboratoriais e clínicos sôbre a atividade esquistossomicida do Hycanthone até agora obtidos mostram a necessidade de novos ensaios com êste promissor medicamento.