HIV-1 infection of neurons might account for progressive HIV-1-associated encephalopathy in children

Direct and productive infection of neurons in vivo is still a matter of debate, although in vitro experiments have demonstrated that immature neuronal cells can be productively infected by various human immunodeficiency virus (HIV) strains. To address this controversy we have analyzed, using light microscopy and in situ hybridization (ISH), HIV-1 infected cells in brain tissue from four pediatric cases of HIV-1-associated encephalopathy (EP). HIV-1 RNA-expressing cells--therefore, actively infected cells--were detected by ISH in different amounts in all brain specimens from the four children. They mainly correspond to glial cells. However, in two of the four children, who had severe progressive EP, but not in the other two, who had the static form, HIV-1-infected neurons were clearly observed in the cortical brain samples. These results provide initial evidence that HIV-1 can actively infect neurons in vivo in children and show a cortical involvement of HIV brain infection in clear correlation with the clinical EP symptoms.

Inflammatory reactions in progressive multifocal leukoencephalopathy after highly active antiretroviral therapy

Three patients with progressive multifocal leukoencephalopathy (PML) treated with highly active antiretroviral therapy (HAART) worsened clinically and radiologically. At the time of deterioration all three had reduced HIV viraemia and increased CD4 cell counts. Brain biopsy in all three disclosed PML and marked perivascular lymphoplasmacytic infiltration. We reviewed the slides of 28 brain biopsies diagnostic of PML. Inflammatory changes were observed in four out of nine patients on HAART and in one out of 19 patients not on HAART.

Amyloid precursor proteins in the cerebellar cortex of Alzheimer's disease patients devoid of cerebellar beta-amyloid deposits: immunocytochemical study of five cases

Five human brains affected by Alzheimer's disease (AD), but without cerebellar amyloid (A beta) deposits, were investigated for the presence and location of amyloid precursor proteins (APP). This was parallel to 6 AD brains with A beta deposits, 6 young controls and 6 age-matched controls. Antibodies against A beta and two epitopes of APP (amino and carboxy terminals, APP(60-100) and APP(643-695), respectively) were employed. Accumulations of APP in neurons (mainly Purkinje cells) and glial cells in the upper part of the molecular layer were far greater than those in age-matched control brains and similar to those in AD brains with A beta deposits. This suggests that changes in APP production and/or metabolism occur before A beta deposition, or that these changes can occur without amyloidogenic processing. More than 60% of positive Purkinje neurons were of normal appearance; most of them showed both APP(60-100) and APP(643-695) immunoreactivity, but a small number (<21%) reacted with only a single antiserum. A small number of Golgi, Lugaro and granule cells were APP immunopositive. In all cases, stellate and basket cells were negative, as were most glial cells other than those of the molecular layer. Folia showed two different appearances, which were particularly well displayed in three cases: "strongly" immunopositive folia with high reactivity in Purkinje cells and other neurons, and "weakly" immunopositive folia with low neuronal reactivity, but with a large number of positive glial cells in the molecular layer. The results are discussed in relation to the possible existence of types or stages of the AD process and local factors, including specific and non-specific cell factors, in the induction of APP accumulation. All these 5 cases were female, but the Apo-E 4 genotype was displayed only in two cases.

Long-term histopathologic findings in two cerebral aneurysms embolized with Guglielmi detachable coils

We present gross pathologic autopsy findings of a patient who was treated for two aneurysms with Guglielmi detachable coils (GDCs), and who died 33 months after the procedure. Histologic findings are also presented. In both aneurysms, the coils were firmly attached to the aneurysmal wall, making it impossible to remove them from the sac. The ostium of one aneurysm was covered by collagenous tissue and a single layer of endothelium.

Nonsurgical cure of isolated cerebral mucormycosis in an intravenous drug user

The case of a 30-year-old, female, HIV-positive intravenous drug user who suffered from isolated cerebral mucormycosis is reported. Treatment with amphotericin B at an accumulative dose of 5.5 grams led to significant recovery, and there was no recurrence of disease over a follow-up period of six months. Patients with isolated cerebral mucormycosis in whom surgery would be a high-risk or impossible procedure could be managed medically with prolonged courses of intravenous amphotericin B.

Fine-needle aspiration cytology of superficial angiomyxoma (myxoid perifollicular fibroma): report of a case

A case of superficial angiomyxoma arising in the areola of a 49-yr-old woman is presented, including both fine-needle aspiration cytology (FNAC) and histological study. The aspirate yielded a rich myxoid background with isolated fusiform cells, showing oval, monomorphic nuclei with minimal atypia. Sometimes these cells were arranged in small fragments without any specific pattern. The absence of mitotic figures, atypia, or cutaneous and breast epithelium suggested a benign myxoid stromal neoplasm. The final diagnosis was established on the excised mass by histopathologic study. The report of this entity in FNAC and the differential diagnosis with other myxoid lesions are discussed, and the feasibility of its cytological diagnosis by FNAC, helped by appropriate clinical information.

Hemangiopericytoma in a male breast. Report of a case with cytologic, histologic and immunochemical studies

A hemangiopericytoma in a male breast was studied by fine needle aspiration (FNA) biopsy. The FNA smears contained tissue clumps showing knob-like formations of atypical cells, spindle-shaped cells and fragments of capillaries lined by normal endothelial cells. Immunocytochemical study showed a positive reaction for vimentin, but a negative reaction for desmin and keratin. Staining for Factor VIII was positive only in the capillaries and endothelial cells. The cytodiagnosis was "mesenchymal tumor." Histopathologic study of the mastectomy specimen made the final diagnosis of hemangiopericytoma. While FNA cytology and immunocytochemistry cannot make a definitive diagnosis of this rare vascular tumor, they can be decisive in planning the surgical treatment, as in the present case.

Fine needle aspiration cytology diagnosis of an extracranial meningioma presenting as a cervical mass

Fine needle aspiration was performed on a cervical mass of unknown etiology in a 78-year-old woman. The cytologic findings were consistent with a meningioma. The diagnosis was confirmed by CT scan, which revealed an intracranial mass with extension through the foramina of the base of the skull to the cervical region. The cytologic findings in meningiomas are discussed, with special reference to the differential diagnostic considerations in extracranial sites.

Malignant cerebellar gliomas. Report of 4 cases with special reference to tissue culture study

The rare malignant cerebellar gliomas have been considered as an unusual form of brain glioblastomas. However, different forms have been described which can be divided into three groups: (a) cerebellar astrocytomas with malignant features; (b) undifferentiated tumors mimicking the cerebral glioblastomas; (c) malignant glioblastomatous recurrences of primary benign cerebellar astrocytomas. The present series is composed of four cases studied with silver impregnation or with tissue culture and time-lapse cinematography. It appears from this study that the cerebellar glioblastomas bear no relationship to the cerebral glioblastoma. Silver impregnation shows many astrocytes taking part in the tumor cell population and the behavior in vitro is similar to that of the common benign astrocytomas from which they seem to be derived. Thus, a sequence can be established: benign cerebellar astrocytoma, malignant cerebellar astrocytoma, cerebellar glioblastoma.