Immunohistochemical staining of brain tissue of a pneumococcal meningitis patient.
In the pneumococcal meningitis FH was expressed in the brain parenchymal cells (a), with strong expression in Purkinje cells (a, asterisk) and in cells in the granular layer (a, arrows). In the control case the parenchyma was negative (b) and FH expression was confined in the blood within blood vessels (b, arrow). Inflammatory cells in the meninges of the pneumococcal meningitis case showed strong expression of FH (c) and macrophages show stronger positivity than granulocytes (c, arrowheads). In the control case, meningeal cells showed variable intensity FH expression (d, arrowheads)