Diagnóstico de Infecção por Eritrovírus B19 em Pacientes com AIDS: imunoistoquímica, hibridização in situ e exame histopatológico da medula óssea

• Autor(a) principal: Setúbal, Sérgio
• Data de Publicação: 2005
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal Fluminense (RIUFF)
• Texto Completo: https://app.uff.br/riuff/handle/1/17541
• topic: Patologia Experimental; Medicina; Clínica Médica; Eritrovírus B19; Parvovírus B19; Imunoistoquímica; Hibridização in situ; Diagnóstico laboratorial; HIV; Infecções por Parvoviridae; Medula óssea; Biópsia; CNPQ::CIENCIAS DA SAUDE::MEDICINA::CLINICA MEDICA::DOENCAS INFECCIOSAS E PARASITARIAS

Erythrovirus B19 infects erythrocytic progenitor cells, leading to a transient interruption of erythropoiesis. It is the causal agent of several clinical syndromes, including erythema infectiosum and its associated (or isolated) joint symptoms; transitory aplastic crisis of individuals with hemolytic anemias; non-immune hydrops fetalis; and the chronic anemias of immunosuppressed patients, including those with AIDS. In this latter setting, erythrovirus B19 assumes certain importance, as it is, among the innumerable causes of anemia in AIDS, a treatable one. Aiming at to look for evidences of erythrovirus B19 infection, bone marrow stored material from 42 autopsies (49 paraffin blocks) and 36 biopsies (48 paraffin blocks from 31 patients)underwent histopathological examinations and immunohistochemical and in situ hybridization tests. As a whole, 97 paraffin blocks, from autopsies and necropsies done from 1988 to 2002, were examined. Eighty-five sections were stained with hematoxylin-eosin (HE) and examined under optical microscopy. In 20 out of these blocks intra-nuclear inclusion bodies displacing the chromatin to the periphery ( lantern cells ), suggestive of erythrovirus B19 infection, were noticed. Eighty-seven sections were also subjected to immunohistochemistry, in which ten were deemed positive. The immunohistochemistry was repeated in these ten sections and seven were again considered positive (two from necropsy material, plus five biopsies from four patients). Nine out of the 10 originally mmunohistochemistry positive sections were also subjected to in situ hybridization, with three positives, one of them strongly. Nine other sections, taken among those that were positive under HE, were also subjected to in situ hybridization, where four were considered positive. Among the techniques used in this study, the most easy-to-do was microscopy of HE-stained sections, the lantern cells being, as described in the literature, easily seen. Most bone marrow sections were normocellular or hypocellular, and many had myelodysplastic changes, plasma cell infiltrates, histiocytosis, and hyperplasia of megacaryocytes, with immature and dysmorphic forms. In spite of the tests being done blindly, there was a regular agreement between HE and immunohistochemistry results, as the percentage of HE positive sections were far greater among the immunohistochemistry positive ones. Among the 15 sections subjected to the three techniques used in the study, only one gave unequivocal positive results with all three. The use of immunohistochemistry and in situ hybridization in the diagnosis of erythrovirus B19 infections in paraffin-stored bone marrow material deserves further study. The frequency of erythrovirus B19 infection in the examined material can be deemed low.