Morphological picture in paroxysmal nocturnal hemoglobinuria. Case report.

25-year-old woman with paroxysmal nocturnal hemoglobinuria was admitted to the hospital because of headache, progressing right hemiparesis and speech disorders. Several days later patient lost consciousness. Cerebrospinal fluid was xanthochromic with increased pleocytosis and protein level. CT-scan revealed ischemic area with hemorrhagic focus within left cerebral hemisphere. Patient died 3 weeks after the admission. Brain section revealed hemorrhagic infarct in the cortex of the left parietal lobe, thrombosis of the superior sagittal sinus and "respiratory brain" changes. Microscopic examination revealed meningeal venous thrombosis, hemorrhagic infarct, vasculitis, abundant accumulation of bacteria within blood vessels, and other pathological changes such as petechiae, perivascular exudates and small, round areas composed of acellular fibrillary network. There were no macrophages and GFAP-positive astrocytes in any of these areas. Authors suggest that weak cell reactivity may be connected with alterations in cell membranes, mainly low phosphatidylinositol (GPI) content.