[Human brucellosis in Burundi. Serologic survey in Rusizi Plain]

A serological survey was carried out on human brucellosis in Rusizi plain in Burundi from october 1984 to september 1985: 1,087 human sera were investigated by means of the rose bengal test and the technic of Wright's sero-agglutination. It comes out of this survey that: the aggregate prevalence of positive serology is 6.6%; such a prevalence is significantly higher in professionally at risk people (7.9%) than in people contaminated by food (3.5%).

[Acute hemorrhagic conjunctivitis, in Cuiabá, Mato Grosso, Brazil 1983]

Foi feita investigação de natureza etiológica clínica e laboratorial durante uma epidemia de conjuntivite hemorrágica aguda (CHA), ocorrida em Cuiabá, MT durante os meses de dezembro de 1982 e fevereiro de 1983; atendidos 68 pacientes e colhidos espécimes da conjuntiva, orofaringe e soro. Em 28 pares de soros foram realizados testes de neutralização em tubos de cultura de tecidos para o enterovirus 70 (EV 70) e fixaço do complemento para os adenovirus. Os resultados revelaram conversão sorológica de 89,3% (25 pares de soro) para o EV 70. A Secretaria de Saúde do Estado do Mato Grosso estima que aproximadamente 70% da população tenha sido atingida durante o surto. Não foram observadas evidências de comprometimento neurológico em pacientes de conjuntivite, durante ou logo após o surto.

The clinical relevance of antinuclear antibodies in connective tissue diseases

Detection of antinuclear antibodies (ANA) is of growing relevance in the management of connective tissue diseases (CTD). ANA are useful diagnostic tools, since most CTD have a peculiar ANA profile, characterized either by restricted specificities, abnormally high titers, or both. Furthermore, the study of the intimate structure and function of nuclear antigens, and of their corresponding antibodies may provide important insights to understand both origin and pathogenesis of CTD. Finally, the more or less close association of ANA levels and/or specificity with certain signs or symptoms of CTD is of increasing help to the clinician in the correct monitoring and management of CTD.

Examination of lochia as an aid to the early diagnosis of bovine brucellosis

The standard technique for diagnosing bovine brucellosis is the serological examination of blood samples. As affected females may excrete large numbers of the Brucella organism in the lochia, the bacteriological and smear examination of such material appeared to be a suitable alternative for early diagnosis. Of the lochia samples collected from 210 cows and heifers within 12-24 h after parturition or abortion, 10.9% were bacteriologically positive. Only 70% of these could be diagnosed correctly as positive by microscopic examination. This technique also resulted in 3.3% false negative and 1.4% false positive diagnoses. Results of the serological examinations of blood, collected simultaneously with the lochia samples, correlated fairly well with those obtained microscopically. Culture of lochia samples on a suitable medium appears to be the method of choice, when dealing with the early diagnosis of bovine brucellosis.

Serological diagnosis of hydatid disease by enzyme linked immunosorbent assay (ELISA) using partially purified hydatid cyst fluid antigens

Experimentally, two hydatid cyst fluid (HCF) antigens (antigens 4 and 5) were found to be the most immunogenic antigens in HCF. The two antigens were precipitated together from HCF. This was done by adding 2M phosphotungstic acid and 2M magnesium chloride solutions to clarified HCF while continuously stirring the mixture. The precipitate formed was suspended in physiological saline (P.S.). This antigens' solution was used to coat microtitre plates for indirect ELISA. Indirect ELISA was performed on 180 randomly selected bovine sera. The sensitivity of the test was found to be 98% while the specificity was 70%. The predictive value was 89%. Although the specificity of the test was relatively low, the test using these partially purified antigens was found to be useful because of its high sensitivity.

[Epstein-Barr virus cerebellitis in an 11-year-old girl]

The authors report an eleven year old girl who manifested predominantly an acute cerebellar syndrome secondary to infection by Epstein Barr Virus. This complication is unusual and males are predominantly affected. The diagnostic and common physiopathological hypothesis are discussed.

The diagnosis of mononucleosis in the office laboratory

Infectious mononucleosis has been known for a long time to be a common infection in young adults. It also infects children. In particular, children under the age of 2 years may not express the illness clinically. Diagnostic criteria vary but in young adults usually include the symptoms of fever, exudative tonsillitis, and cervical lymphadenopathy. Usually, there is a relative and absolute lymphocytosis, with 10 to 20 per cent or greater atypical lymphocytes. Rapid slide tests are accurate and economical and support the diagnosis when positive. False-positive results are known to occur with several other important disease processes; therefore, the clinical presentation and laboratory results must be interpreted in their appropriate context. Quality control is essential even for the rapid slide tests, and experienced examiners are required to review blood smears. The morphology of atypical lymphocytes varies greatly. In addition, morphology interpretation can be hampered by problems in preparation of slides or the holding of blood samples awaiting slide preparation. EBV-specific serodiagnosis has significantly enhanced our ability to study further and differentiate heterophil-negative syndromes that share clinical features with infectious mononucleosis. Acute, past, chronic, and no EBV infection can now be differentiated. Further diagnostic tests for other etiologic agents are necessary when all EBV tests are negative and the clinical situation requires appropriate diagnosis.

Cytomegalovirus immunity and T lymphocytes in bone marrow donors and acute graft-versus-host disease

T lymphocyte subset numbers in bone marrow grafts were correlated with the cytomegalovirus (CMV) antibody status of the donors and with the occurrence of acute graft-versus-host disease (GVHD) in their recipients. We studied whether or not the (previously reported) association between donor CMV antibodies and GVHD could be explained by CMV-related changes in T cell subsets in the marrow grafts. There were no significant correlations between any of the T cell subsets in the marrow grafts and the occurrence of grades II-IV GVHD. A particular subset of CD8+ T cells carrying the HNK1 marker was significantly increased in the marrow grafts of CMV-seropositive donors. Although recipients of marrow from CMV-seropositive donors received an average of five times more CD8+ HNK1+ T cells than those with CMV-seronegative donors, that situation was not associated significantly with the development of GVHD.

Hydatid liver disease, is it a diagnostic problem? Analysis of 42 consecutive cases in Saudi patients

Analysis of 42 patients clinically suspected of having hydatid liver disease is presented. Diagnosis was made using clinical criteria, serology, skin tests and non-invasive imaging techniques. The distribution of the cysts according to age, sex, location and number is discussed. It is suggested that histopathological study is no longer essential to confirm the diagnosis of hydatid disease of the liver.

An evaluation of diagnostic methods for bovine brucellosis in Libya

A total of 8,607 animals were examined for detection of brucellosis using blood serum agglutination as well as complement fixation tests. out of 8,607 sera samples examined, 125 sera played positive serum agglutination reactions in significant levels for brucella (1.45%). The percentage of reactors to the complement fixation test in the examined cattle was 1.82%. The relation between positive or doubtful cases of serum tube agglutination as regards to their complement fixation results were discussed in detail.

Single-serum radial hemolysis to detect recent rubella virus infection

In the radial hemolysis test for rubella virus-specific antibodies, sera obtained shortly after primary rubella produce a characteristically altered hemolysis zone, termed soft hemolysis. The occurrence of soft hemolysis was analyzed statistically in 6,723 sera. The specificity of soft hemolysis for infection with rubella virus was 99.0%. Its sensitivity in primary infections was 97.3%, and the predictive value for rubella serodiagnosis (increase in IgG level or detectable IgM) was 91.2%. The temporal association of soft hemolysis with rubella was determined with sera obtained from 129 persons during late convalescence (70-310 days after onset of symptoms). Soft hemolysis disappeared by 190 days after the onset of symptoms and the presence of ordinary hemolysis ruled out primary rubella in the preceding 70-100 days. Soft hemolysis was caused by IgG antibody to rubella virus, and thus represents a new serodiagnostic principle. This technique, together with an Igm assay, allows rapid diagnosis of recent rubella from a single serum sample.

Flaviviruses in South Africa: diagnostic procedures

Employing rabbit immune serum, 10 flaviviruses known to be present in South Africa could be divided into 5 serological subgroups. The subgroups conform to the general pattern described for the group. Sera from experimentally infected calves and lambs were monospecific in neutralization tests, but cross-reacted in haemagglutination inhibition tests. These results suggest that sheep and cattle sera from the field can best be tested by microneutralization tests. The greater sensitivity of embryonated hen's eggs for some viruses and of one-day-old mice for other viruses necessitates the employment of both systems for the isolation of flaviviruses from field specimens.