Evaluation of human brain damage in fire fatality by quantification of basic fibroblast growth factor (bFGF), glial fibrillary acidic protein (GFAP) and single-stranded DNA (ssDNA) immunoreactivities

Burns and inhalation of toxic gases, including carbon monoxide (CO) and cyanide, which are produced by combustion, are major factors involved in fire death. The present study immunohistochemically investigated basic fibroblast growth factor (bFGF), glial fibrillary acidic protein (GFAP) and single-stranded DNA (ssDNA) in the brains of fire fatalities (n = 49) to examine the differences between fatal burns and CO intoxication, compared with those in cardiac deaths (n = 24) and mechanical asphyxiation cases (n = 23). In acute fire fatality, neuronal ssDNA immunopositivity in the cerebral cortex of the parietal lobe was high in both fatal burns and fatal CO intoxication, but that of the pallidum was higher for CO intoxication than for burns. The number of neurons was decreased in prolonged fire deaths, irrespective of the severity of burns or CO intoxication, but glias were increased in cases of fatal burns. Prolonged deaths due to burns had a higher glial bFGF immunopositivity in the cortex and white matter, higher and lower glial GFAP immunopositivity in the cortex and white matter, respectively, and a low neuronal ssDNA immunopositivity in the cerebral cortex and hippocampus. In prolonged deaths due to CO intoxication, however, glial bFGF and GFAP immunopositivities were low at each site, but neuronal ssDNA immunopositivity showed a higher value. These observations suggest increased cerebral neuronal ssDNA immunopositivity to be a finding of vitality in acute fire death, and a neuronal loss accompanied by active glial responses after severe burns, and a neuronal loss and progressive apoptosis without glial responses after CO intoxication to be characteristic in prolonged death.