Marcelo Simão Ferreira

Detection of IgG in cerebrospinal fluid for diagnosis of neurocysticercosis: evaluation of saline and SDS extracts from Taenia solium and Taenia crassiceps metacestodes by ELISA and immunoblot assay

We compared saline (S) and sodium dodecyl sulphate (SDS) extracts from Taenia solium (homologous species – HO) and Taenia crassiceps (heterologous species – HE) metacestodes in order to detect IgG by ELISA and immunoblot assay (IBA) in cerebrospinal fluid (CSF) for the diagnosis of human neurocysticercosis (NC). CSF samples were obtained from 93 patients. Of these, 40 had NC, five had a diagnosis of probable NC, nine had central nervous system schistosomiasis or strongyloidiasis and 39 had other neurological alterations. Samples were analysed by ELISA and the results were compared with IBA in all samples with confirmed and probable NC diagnosis, in all samples with other central nervous system parasitic infection, and in 10 of those with another neurological alterations. ELISA sensitivity was 100%, 85%, 95% and 87.5% for the S‐HO, S‐HE, SDS‐HO and SDS‐HE extracts, respectively, and ELISA specificity was 100% for S‐HO, S‐HE, SDS‐HO extracts and 97.9% for SDS‐HE antigen. Immunodominant peptides detected by IBA were, by decreasing percentage of recognition: 64–68 and 45 kDa for S‐HO; 108–114, 92–95, 64–68, 83 and 88 kDa for S‐HE; 64–68, 108–114, 77 and 86 kDa for SDS‐HO; and 108–114, 88 and 92–95 kDa for SDS‐HE. Overall the homologous antigenic extracts showed higher sensitivity than the heterologous extracts in the diagnosis of NC in CSF samples. The heterologous extracts contained most of the immunodominant peptides presented in the homologous extracts, which are recognized by IgG antibodies in CSF samples.

Imaging Trypanosoma cruzi within tissues from chagasic patients using confocal microscopy with monoclonal antibodies.

Abstract Confocal fluorescence microscopy combined with differential interference contrast imaging of tissues from chagasic patients enabled the unequivocal identification of the parasite Trypanosoma cruzi. Using different monoclonal antibodies that indicate the parasite form and replication stage in conjunction with DNA labelling, specimens derived from distinct clinical forms of the disease were examined. Intracellular amastigote forms of the parasite were clearly detected in heart, brain, skin, lung, and kidney. Dividing amastigotes as well as trypomastigote forms were recognized in samples obtained from patients undergoing either acute-phase or some form of reactivation caused by immunosuppression.

Agreement between premortem and postmortem diagnoses in patients with acquired immunodeficiency syndrome observed at a brazilian teaching hospital

Acquired immunodeficiency syndrome (AIDS) is one of the main causes of death in adults worldwide. More commonly than in the general population, in patients with AIDS there is substantial disagreement between causes of death which are clinically suspected and those established by postmortem examination. The findings of 52 postmortem examinations were compared to the premortem (clinical) diagnoses, and there was 46% agreement between them. Fifty two percent of the patients had more than one postmortem diagnosis, and 48% had at least one AIDS-related disease not suspected clinically. Cytomegalovirus infection was the commonest (30.7%) autopsy finding, but not a single case had been suspected premortem. Bacterial infection, tuberculosis, and histoplasmosis were also common, sometimes not previously suspected, postmortem findings. This study shows that multiple infections occur simultaneously in AIDS patients, and that many among them are never suspected before the postmortem examination. These findings suggest that an aggressive investigation of infections and cancers should be done in patients with AIDS, particularly in those who do not respond to therapy of an already recognized condition.

Congenital toxoplasmosis in Uberlândia, MG, Brazil

Almost all babies suffering from congenital toxoplasmosis, if undiagnosed and untreated, will develop visual or neurological impairments by adulthood. The aim of this study was to investigate the occurrence of congenital toxoplasmosis in two hospitals from Uberlândia, Brazil. A total of 805 serum samples of cord blood were collected, 500 from public hospital and 305 from private hospital, and all patients answered a questionnaire about pregnancy and newborns. ELISA was accomplished to detect IgG antibodies to Toxoplasma gondii and positive sera were re-tested to verify specific IgM and IgA antibodies in a capture ELISA. Seroprevalence of IgG antibodies against T. gondii was 51.6 per cent in the hospitals, while the frequency of congenital toxoplasmosis was 0.5 per cent, with specific IgM and/or IgA antibodies. The main clinical alteration was chorioretinitis (an inflammatory process of the retina and uveal tract). The high seroprevalence in this population and expressive rate of congenital disease show the requirement of screening programmes for toxoplasmosis during pregnancy.

Population Genetics, Evolutionary Genomics, and Genome-Wide Studies of Malaria: A View Across the International Centers of Excellence for Malaria Research.

The study of the three protagonists in malaria—the Plasmodium parasite, the Anopheles mosquito, and the human host—is key to developing methods to control and eventually eliminate the disease. Genomic technologies, including the recent development of next-generation sequencing, enable interrogation of this triangle to an unprecedented level of scrutiny, and promise exciting progress toward real-time epidemiology studies and the study of evolutionary adaptation. We discuss the use of genomics by the International Centers of Excellence for Malaria Research, a network of field sites and laboratories in malaria-endemic countries that undertake cutting-edge research, training, and technology transfer in malarious countries of the world.

Mielite transversa como manifestação clínica inicial de linfoma não Hodgkin disseminado e mielopatia vacuolar associada ao HIV: relato de caso

Non-Hodgkin lymphoma is frequently seen in AIDS patients usually affecting the central nervous system (CNS), especially the leptomeninges and the cerebral hemispheres. The epidural involvement is rarely described, ranging from 3.5% to 8.3% among the CNS sites. The authors present a case of disseminated non Hodgkin lymphoma associated to vacuolar myelopathy in a 27 years-old male patient with AIDS emphasizing the importance of this differential diagnosis in the myelopathies of AIDS.