[Retroperitoneal lymphangiomyomatosis. Immunohistochemical and ultrastructural study of a case]. / Linfangiomiomatosi ad esordio retroperitoneale. Studio immunoistochimico ed ultrastrutturale di un caso.

A case of retroperitoneal lymphangiomyomatosis occurring in a 34-year-old woman is reported. Alpha-smooth muscle actin and desmin were localized in the proliferating cells. Electron microscopy showed the presence of many thin perinuclear myofilaments with dense bodies. The differential diagnosis with leiomyosarcoma has been taken into consideration.

Massive neuronal destruction in human immunodeficiency virus (HIV) encephalitis. A clinico-pathological study of a pediatric case.

Human immunodeficiency virus (HIV) encephalitis in children with AIDS includes a diffuse white matter disease associated with an inflammatory cell infiltrate that features multinucleated giant cells. Cerebral cortex is relatively preserved and only focal loss of Purkinje cells in the cerebellum has been observed. We describe a case of encephalitis in a child with AIDS in which there was massive and diffuse destruction of the cerebral cortex with severe neuronal loss, marked inflammatory perivascular infiltrate with abundant multinucleated cells and large pleomorphic reactive astrocytes. Similar findings were present in the basal ganglia. Moreover, the cerebellum disclosed a complete loss of Purkinje and granule cells. These findings could not be related to an ischemic mechanism or to an associated opportunistic infection. Electron microscopy showed numerous HIV particles. This case illustrates a different pattern of CNS involvement by HIV and emphasizes the destructive capacity of this neurotropic virus for neural tissue.