Prominent cortical atrophy with neuronal loss as correlate of human immunodeficiency virus encephalopathy

A 25-year-old homosexual AIDS patient presented with progressive cognitive, motor and behavioral disturbances consistent with HIV encephalopathy. CT scans demonstrated progressive diffuse brain atrophy. Neuropathology showed predominant cortical changes including severe neuronal loss corroborated by morphometry. Only minimal changes were found in the white matter and basal ganglia. Immunocytochemistry for HIV stained occasional microglial cells more markedly in the cerebral cortex. This suggests that HIV infection of the brain may cause predominant cortical nerve cell loss, and that HIV encephalopathy is not necessarily due to white matter lesions.

Cerebral lymphoma and HIV encephalitis in a case of paediatric AIDS, with pre-existing multicystic encephalomalacia

A case of intracerebral malignant B cell lymphoma associated with encephalitis typical of Human Immunodeficiency Virus (HIV) infection is described in a 4 year old child, with post-transfusion Acquired Immune Deficiency Syndrome (AIDS) and severe pre-existing cystic encephalomalacia. This report further documents B cell lymphoma as the commonest cause of an intracerebral mass, and an important cause of death in paediatric AIDS. That more than one pathological process may be responsible for neurological symptoms in paediatric AIDS is also emphasised.

Multifocal multinucleated giant cell myelitis in an AIDS patient

A 19-year-old male intravenous drug abuser, was admitted to hospital with a one-week history of lower limb weakness and urinary retention. He was known to have been HIV-seropositive for 3 years and had been treated for cerebral toxoplasmosis. Neurological examination confirmed flaccid paraparesis with weak ankle jerks and bilateral extensor plantar responses. There was no obvious sensory deficit. Neurological examination was otherwise normal. CSF contained 63 mg/dl protein and 10 leucocytes/mm3. Myelography was normal. He died 1 month later from septic peritonitis. Neuropathological examination showed chronic lesions of toxoplasmosis in brain. Small necrotic foci with myelin loss, proliferation of microglia, macrophages and multinucleated giant cells (MGC) were disseminated in the whole spinal cord, mostly in the white matter, but the brain was spared. Immunohistochemistry demonstrated p24 and p17 HIV antigens in macrophages, MGC and microglial cells. These lesions resemble those of so called 'multifocal giant cell encephalitis'. The present case demonstrates that HIV-related multifocal inflammatory changes may be restricted to the spinal cord and may be a cause of myelopathy in AIDS patients.

Ischaemic myelopathy secondary to disseminated intravascular coagulation in AIDS

A 39-year-old patient with AIDS presented with a rapidly progressive myelopathy with a partial Brown-Séquard syndrome. He died, 9 weeks after onset of the first neurological signs, from diffuse encephalopathy. Neuropathological examination revealed multiple, usually small, frequently haemorrhagic, infarcts or various ages and numerous fibrin thrombi in medium and small penetrating vessels and capillaries of the brain and spinal cord, characteristic of disseminated intravascular coagulation. There were no inflammatory changes. Immunohistochemical studies for human immunodeficiency virus, cytomegalovirus, varicella zoster virus, herpes simplex virus type 1 and type 2 were negative. Ischaemic spinal cord lesions due to disseminated intravascular coagulation may represent an unusual cause of focal, non-inflammatory, non-tumoral, myelopathic syndrome in AIDS.

Fulminating multiple sclerosis-like leukoencephalopathy revealing human immunodeficiency virus infection

A 66-year-old French homosexual man and a 42-year-old Brazilian man with no known risk factors for HIV infection developed headaches, asthenia, and neurologic episodes of abrupt onset. CT showed multiple hypodense, nonenhancing lesions. Serology for HIV was positive. They died respectively 2 months and 1 month after onset of the illnesses. Autopsy in both cases showed multiple, well-demarcated, demyelinating foci in the white matter of the cerebral hemispheres, brainstem, and cerebellum with histologic features characteristic of recent plaques of multiple sclerosis. There were no multinucleated giant cells or microglial nodules. Immunostaining for HIV was negative. Although a random coincidence of MS and HIV infection cannot be ruled out, the close temporal relationship between the 2 disorders suggests a possible etiologic association.

Cerebral amyloid angiopathy and granulomatous angiitis: immunohistochemical study using antibodies to the Alzheimer A4 peptide

Neuropathologic study of an 82-year-old male who died from massive cerebral hemorrhage showed extensive amyloid angiopathy, with morphologic and immunohistochemical characteristics similar to those observed in Alzheimer's disease, associated with granulomatous angiitis, including the presence of numerous giant cells. Some of the giant cells contained, in their cytoplasm, congophilic material immunoreactive for the Alzheimer A4 peptide, supporting the hypothesis that the granulomatous angiitis may, in part, represent a foreign body reaction to A4 amyloid deposition.

Cytomegalovirus encephalopathy in an infant with congenital acquired immuno-deficiency syndrome

A female infant born pre-term to a HIV seropositive mother presented at birth with seropositivity for HIV and CMV viruria. At five months of age she developed an AIDS-related complex. Six months later she died from rapidly progressive diffuse encephalopathy. Post mortem examination revealed generalized CMV infection. Neuropathological examination showed a nodular encephalitis with occasional cytomegalic cells containing characteristic CMV inclusion bodies. There was no evidence of HIV encephalitis; immunostaining for HIV antigen (gp 41) was negative. Opportunistic infections in infants with congenital AIDS are the exception. To our knowledge, only one case of CMV encephalitis in an infant with congenital AIDS has been reported previously. In that case, as in the present one, a reactivation of a congenital CMV infection is likely.

Immunohistochemical study of cerebral amyloid angiopathy. III. Widespread Alzheimer A4 peptide in cerebral microvessel walls colocalizes with gamma trace in patients with leukoencephalopathy

Brain tissue from 11 patients with cerebral amyloid angiopathy, changes of Alzheimer's disease, and variable degrees of subcortical leukoencephalopathy was examined by immunohistochemical methods, using primary antibodies to peptide segments representing portions of the Alzheimer A4 (beta-) peptide or gamma-trace peptide (seen most commonly in Icelandic patients with cerebral hemorrhage (hereditary cerebral hemorrhage with amyloidosis [HCHWA-I]). Variable A4 immunostaining was seen within cortical (and rarely white matter) parenchyma in the form of senile plaques (with or without central cores), and within capillary and arteriolar walls. Within individual patients, A4 deposits were often primarily parenchymal or vascular, and when they were vascular they tended to be more prominent in arteriolar than in capillary wall segments. Perivascular A4 deposits were often detected around strongly immunoreactive microvessels. Gamma-trace immunoreactivity was noted in many A4-positive microvessel walls, but staining was always less intense than with the anti-A4 antibody. We conclude that patients with severe cerebral amyloid angiopathy may show wide variation in the severity and topography of A4 deposits within brain parenchyma. A4 may colocalize with gamma-trace peptide, suggesting that A4 and gamma-trace forms of cerebral amyloid angiopathy may not be as biochemically distinctive as has been suggested. Other proteases or protease inhibitors may contribute to the pathogenesis of cerebral amyloid angiopathy or cerebral amyloid angiopathy-related stroke syndromes.

Dengue: neuropathological findings in 5 fatal cases from Brazil

Neuropathological examination of 5 patients with dengue who died of shock in Rio de Janeiro during an outbreak in summer 1987, showed nonspecific lesions (edema, vascular congestion, hemorrhagic foci and perivascular lymphocytic infiltrates). In one case with delayed marked neurological symptoms, several foci of perivenous demyelination were observed. Neurological manifestations are various and not uncommon in dengue, but their anatomical substratum is not known. An immunopathological mechanism has been postulated in some cases but has never been demonstrated morphologically. The perivenous leukoencephalitis observed in one of our cases could represent the morphological substratum of such an immunological mechanism.

Spinal cord lesions in the acquired immune deficiency syndrome (AIDS)

Spinal cord involvement in AIDS is not uncommon. Different types of lesions corresponding to varying pathogenetic mechanisms have been reported. Vacuolar myelopathy is the most frequently found. The symptoms and pathological changes resemble those of subacute combined degeneration; however, cobalamine or folate levels have always been found normal. Its frequent association with the multi-nucleated giant cells characteristic of HIV encephalitis makes it likely that the virus plays a role in its pathogenesis. Cytomegalovirus may be responsible for acute myeloradiculitis involving the spinal roots of the cauda equina and inferior part of the spinal cord. In cases of Herpes simplex virus myelitis has been reported; they are usually associated with cytomegalovirus infection and are due to herpes simplex virus type II. Secondary spread from systemic lymphomas may involve the subarachnoid space of the cord and the spinal roots. Compression of the spinal cord by epidural lymphomatous masses has also been described. Spinal infarcts may be secondary to acute or chronic vasculitis or to less specific vascular processes such as disseminated intravascular coagulation.

Cytomegalovirus (CMV) encephalomyeloradiculitis and human immunodeficiency virus (HIV) encephalitis: presence of HIV and CMV co-infected multinucleated giant cells

A 25-year-old homosexual male with AIDS presented with a cauda equina syndrome clinically suggestive of cytomegalovirus (CMV) myeloradiculitis. He was treated with ganciclovir with transient improvement of neurological signs and died 4 months after onset of neurological signs. Neuropathological examination revealed human immunodeficiency virus (HIV) encephalitis, CMV subependymal encephalitis and CMV myeloradiculitis. The latter was characterised by myelin loss, Schwann cell proliferation and presence of CMV early antigens in the nuclei of S-100 protein-positive cells in the spinal roots. In the subependymal regions, morphologically characteristic multinucleated giant cells, positive for CD68, contained early CMV antigens (E13) in their nuclei and HIV antigens (gp41 and p24) in their cytoplasm. The observation that HIV and CMV can co-infect the same cell in vivo raises the possibility of a direct synergistic interaction of both viruses at cell level. This suggests that CMV may play a role as a co-factor in the pathogenesis of HIV encephalopathy.

Diffuse "encephalitic" cerebral toxoplasmosis in AIDS. Report of four cases

Four patients with AIDS presented with a rapidly fatal global neurological illness. CT did not show any focal lesion and gross post mortem examination of the brain was normal in three of the four cases. Microscopic examination revealed numerous widespread microglial nodules in the brain parenchyma, most containing central toxoplama cysts or free tachyzoites. Such diffuse, non-necrotic, "encephalitic" forms of cerebral toxoplasmosis appear unique to AIDS and, to our knowledge, have not been documented previously. They represent a treatable, often misdiagnosed cause of diffuse neurological involvement in AIDS patients.

Acute myeloradiculitis due to cytomegalovirus as the initial manifestation of AIDS

A 26 year old male intravenous drug abuser presented with rapidly progressive paraplegia and total incontinence. CSF examination showed elevated protein level and pleocytosis. HIV testing was positive. Anti CMV titres were mildly elevated in serum and CSF. Death occurred 26 days after the onset of neurological signs. Necrotic and inflammatory lesions with numerous inclusion bodies characteristic of CMV were found in the roots of the cauda equina, conus terminalis and lumbar segments of the spinal cord. CMV subependymal encephalitis and HIV encephalitis were also present.

Pathology of the central nervous system in 40 cases of acquired immune deficiency syndrome (AIDS)

The central nervous system was examined in 40 AIDS patients who died between August 1982 and 1987. The cases included two children born to intravenous drug abusers and 38 male adults. The brains of eight patients who had no clinical or radiological evidence of central nervous system involvement showed non-specific changes which included microglial nodules, perivascular mononuclear cuffs, mineralization of blood vessels and granular ependymitis. In 32 brains from patients with neurological symptoms, toxoplasmosis was the most frequent finding (19 cases) manifested by multifocal, necrotic lesions or a diffuse pseudo-encephalitic process. Other opportunistic infections included cytomegalovirus (eight cases), progressive multifocal leucoencephalopathy (two cases), cryptococcosis (one case), aspergillosis (one case), multiple bacterial microabscesses (one case) and Mycobacterium avium intracellulare (one case). Two patients had cerebral lymphoma. Subacute encephalitis with white matter lesions and multinucleated giant cells characteristic of HIV infection was present in 15 cases. Various combinations of all these infections were encountered in the same brain, sometimes in the same area and, occasionally, in the same cell.

Adult polyglucosan body disease (APBD)

Three patients aged 63, 63 and 74 years had various combinations of progressive lower and upper motor neuron dysfunction, sensory loss, urinary incontinence and dementia. Postmortem examinations in two cases showed moderate cerebral and spinal atrophy, ill-defined areas of incomplete myelin loss in white matter and small necrotic foci in the white matter of gyri, around the basal ganglia and near the dentate nuclei. The main microscopic abnormality was a massive accumulation of PAS-positive polyglucosan bodies (PB) of various sizes and shapes in the cerebral hemispheres, brainstem, cerebellum, spinal cord, nerve roots and nerves. These PB were found in the processes of nerve cells and astrocytes, but not in their perikarya. Similar PB were present in peripheral nerves and in the lungs, heart, liver and kidneys. In the third case, a nerve biopsy revealed several, unusually large, PB in the axons of myelinated fibers. These clinicopathologic features are consistent with adult polyglucosan body disease (APBD) and are distinctive from other conditions in which PB may accumulate. Twelve similar cases have been reported previously. The diagnosis can be made by nerve biopsy. The pathogenesis of APBD is not known, but it may be a polysaccharide storage disease.

The neuropathology of the acquired immune deficiency syndrome (AIDS). A review

The nervous system has been involved in the majority (at least 75%), of cases of acquired immune deficiency syndrome (AIDS) examined postmortem, but the pathogenetic mechanisms involved are not well understood. The predominant pathological process is opportunistic infection secondary to the decrease of T-helper (T4) cells and includes toxoplasmosis, encephalitis due to cytomegalovirus and progressive multifocal leucoencephalopathy. On the other hand, mycoses (mainly cryptococcosis) are relatively uncommon. Primary lymphomas are three times more common than secondary lymphoma spreading from other sites. Cerebral involvement by Kaposi sarcoma is metastatic, probably from primary foci in the lungs. Lesions due to the direct involvement of the nervous system by the human immune deficiency virus (HIV) include subacute encephalitis and vacuolar myelopathy. The former is reported with increasing frequency and is localized predominantly to the white matter in which multinucleated giant cells can be found. These are considered typical of AIDS and have been shown to contain HIV particles in their cytoplasm. AIDS lesions due to infectious agents do not always conform to the typical pattern of the uncomplicated disease and not uncommonly there is evidence of more than one infectious agent in the same area. Peripheral nervous system lesions in HIV infections, responsible for a variety of clinical symptoms, usually appear, in biopsy material, as nonspecific inflammatory in type. CMV inclusions and lymphomatous infiltrations of peripheral nerve have been reported in autopsy cases.

Tumor-simulating giant serpentine aneurysm of the posterior cerebral artery

A case of a giant aneurysm of the proximal segment of the posterior cerebral artery is reported. Complete neuroradiologic (computed tomography scan, angiography, magnetic resonance imaging) and pathological studies were performed. This type of aneurysm is extremely rare and may be difficult to differentiate from a cerebral tumor, both clinically and on computed tomography scan. Vertebral angiography is usually necessary to make, or confirm, the diagnosis.

Quantitative study of lateral horn cells in 15 cases of multiple system atrophy

Nerve cell counts of the lateral horns of the spinal cord were performed in 15 cases of multiple system atrophy (MSA) and three age- and sex-matched controls. The patients with MSA were comprised of eight with severe postural hypotension, three with orthostatic hypotension and little or no disability and four without any signs of autonomic failure. All cases of MSA had lost more than half their lateral horn cells but nerve cell loss could not be correlated with the degree of dysautonomia. These results confirm the involvement of the intermediolateral columns of the spinal cord in MSA. However, the lack of correlation between cell loss and severity of autonomic failure in our cases, suggests that lesions of other sites, such as sympathetic ganglia or the dorsal vagal nuclei, are also implicated in dysautonomia.

Pathological findings in three non-Japanese patients with the POEMS syndrome

The pathological features of three European patients with plasma cell dyscrasia, osteosclerosis and a multisystem disorder, most frequent in Japan, that includes polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes (POEMS syndrome), are reported. The material was obtained from biopsies (peroneal nerve, lymph node) and general autopsy, including hypophysis, in one case. The most salient findings were: peripheral nerve lesions, including both segmental demyelination and axonal degeneration, with so-called uncompacted myelin lamellae (UML); angiofollicular lymph node hyperplasia (AFLNH); and non inflammatory vascular changes. Though not specific, it appears that UML and AFLNH may be contributive findings in atypical cases of POEMS syndrome (incomplete forms, lack of underlying malignant plasma cell dyscrasia or circulating monoclonal immunoglobulin). Among the various autopsy findings we emphasize the skin thickening which was secondary to a hyaline sclerosis of the papillary dermis, and the presence in adenohypophysis of numerous cells showing positive reactions with the anti-alpha MSH antibody. Though immunological, vascular and hormonal disturbances have been implicated at the origin of several manifestations of the disorder, the pathogenesis of the POEMS syndrome remains obscure.

Expanding cerebellar lacunes due to dilatation of the perivascular space associated with Binswanger's subcortical arteriosclerotic encephalopathy

An 80-year-old hypertensive woman developed right hemiplegia and died 24 hours after admission. Neuropathologic examination revealed multiple cerebral infarcts of various ages and diffuse subcortical arteriosclerotic encephalopathy. Clusters of asymptomatic "expanding" lacunes, due to dilatation of the perivascular spaces, were found in both dentate nuclei. These cavities, which presented as space-occupying lesions, were surrounded by a single layer of flattened cells and contained 1 or more sections of normal-looking arterioles. Such a topographic grouping of lacunes in the dentate nucleus has not been described previously. The mechanism of widening of the perivascular compartment remains unclear; its occurrence in a hypertensive patient and its association with typical Binswanger's subcortical arteriosclerotic encephalopathy and severe atherosclerosis with multiple infarcts suggest a common pathophysiologic mechanism possibly including an alteration of the blood-brain barrier.

Effect of negative air ionization on hyperactive and autistic children

Twenty-one attention deficit disorder with hyperactivity and seven autistic children were randomly exposed to negatively ionized and ambient atmospheres under rigorously controlled experimental conditions. The negatively ionized condition did not significantly affect measurements of activity level, impulsivity, reality orientation, destructive/constructiveness, attention, or task performance. Significant results might be obtained if subgroups of known hyperserotoninemic autistic and attention deficit disorder children were exposed to negatively ionized conditions.

Posterior callosal infarction. Clinicopathological correlations

Clinicoanatomical observations on a patient with partial interhemispheric disconnection associated with complete ischaemic destruction of the splenium and of the posterior part of the body of the corpus callosum are presented. Neuropathological examination of the areas containing degenerated white matter indicated that the lesions affected the transcallosal fibres that link the cortex of the occipital lobes and the superior parietal lobules (SPL). The white matter situated in the temporal lobes was intact. This suggests that in man, and contrary to what has been described in the monkey, the callosal pathway followed by the temporal fibres is rostral to the one followed by the parietal or at least by the SPL fibres. The most prominent disconnection syndrome elements were left tactile anomia (in spite of a rather good tactile-motor integration between the hemispheres), left visual anomia, agraphia of the left hand and 'diagnostic' apraxia. The fact that the anterior part of the corpus callosum was intact accounts for the preservation of interhemispheric transfer of somatic sensory information and for the absence of left extinction during the dichotic listening test. An attempt is made to give a more detailed explanation of the results obtained during the different tests.

Aspergillosis of ethmoid sinus and optic nerve, with arteritis and rupture of the internal carotid artery

A 54-year-old woman had been treated 26 years previously for Hodgkin's disease. Eight months before presentation, the disease had recurred and the patient had received cytotoxic drugs and steroids. She presented with loss of vision of the right eye and died 5 months later from extensive subarachnoid hemorrhage. Postmortem examination revealed an aspergillus abscess of the ethmoid sinus, extending to the right frontal lobe and optic nerve, and to the wall of the right internal carotid artery (ICA). Death was due to rupture of the ICA. Such a presentation of aspergillosis is unusual. Three cases of aspergillus arteritis causing rupture of the ICA have been reported previously.

Pigmentary type of orthochromatic leukodystrophy (OLD): a new case with ultrastructural and biochemical study

A 34-year-old woman with no family history of orthochromatic leukodystrophy (OLD) developed progressive intellectual deterioration, a frontal syndrome and spastic tetraparesis. She died four years after the onset of the clinical illness. Neuropathological studies included light and electron microscopy of cerebral and nerve biopsies, and a complete postmortem examination. Light microscopy demonstrated OLD with pigmented macrophages and glial cells. Electron microscopy showed electron-dense, membrane-bound intracytoplasmic lamellar inclusions with curved or straight parallel arrangement, or fingerprint pattern, in white matter macrophages, astrocytes and oligodendrocytes. Cortical cells contained lipofuscin which was normal in type and amount. This suggests that the material in white matter glial cells and macrophages is ceroid pigment, however, the distribution is not that seen in ceroid-lipofuscinosis. Similar inclusions have been found in oligodendrocytes in other forms of OLD. Biochemical study did not show evidence of demyelination. Galactolipids were normal. Polyunsaturated fatty acids were decreased. The most striking feature was an increase in plasmalogens.

Cholinesterase assay automated in the Cobas-Bio centrifugal analyzer

We describe a method for measuring plasma cholinesterase (EC 3.1.1.8) and dibucaine and fluoride numbers by using the Cobas-Bio. Benzoyl choline chloride is used as substrate. Reaction conditions are the same as in the corresponding manual method. The reaction is stopped with physostigmine. Choline oxidase (EC 1.1.3.17) is coupled with 4-aminoantipyrene. In the presence of peroxidase (EC 1.11.1.7), the 2-hydroxy-3,5-dichlorobenzenesulfonate indicator reaction gives a red product, measured at 505 nm. The analyzer is used in the "Multi Run" mode, with plasma cholinesterase and dibucaine and fluoride inhibition concurrently measured for eight samples. Coefficients of correlation between the manual and present method for plasma cholinesterase and dibucaine and fluoride numbers in 40 patients of various phenotypes were 0.843, 0.923, and 0.717, respectively. The inter-batch CV for each of the three assays was 2% to 3%.

Cholinesterase assay automated in the Cobas-Bio centrifugal analyzer

We describe a method for measuring plasma cholinesterase (EC 3.1.1.8) and dibucaine and fluoride numbers by using the Cobas-Bio. Benzoyl choline chloride is used as substrate. Reaction conditions are the same as in the corresponding manual method. The reaction is stopped with physostigmine. Choline oxidase (EC 1.1.3.17) is coupled with 4-aminoantipyrene. In the presence of peroxidase (EC 1.11.1.7), the 2-hydroxy-3,5-dichlorobenzenesulfonate indicator reaction gives a red product, measured at 505 nm. The analyzer is used in the "Multi Run" mode, with plasma cholinesterase and dibucaine and fluoride inhibition concurrently measured for eight samples. Coefficients of correlation between the manual and present method for plasma cholinesterase and dibucaine and fluoride numbers in 40 patients of various phenotypes were 0.843, 0.923, and 0.717, respectively. The inter-batch CV for each of the three assays was 2% to 3%.

'Expanding cerebral lacunae' in a hypertensive patient with normal pressure hydrocephalus

A hypertensive patient who had been treated successfully for normal pressure hydrocephalus (NPH), died from a left thalamic haemorrhage. Neuropathological examination showed recent and old thalamic haematomas and numerous parenchymal cavities or 'cerebral lacunae'. Two lacunae bulged into the lateral ventricles, and had all the characteristics of so called 'expanding lacunae'. They were surrounded by a single layer of epithelial-like cells, contained a normal, patent, arteriole, and presented as space occupying lesions. Only two similar cases have been reported previously. The complexity of the neuropathological features of 'cerebral lacunae' is emphasized and the relationships between cerebral hypertensive disease, NPH, and expanding lacunae are discussed.

Chronic localised encephalitis (Rasmussen's) in an adult with epilepsia partialis continua

A 29 year old male presented with epileptic fits, progressive left sided focal seizures and epilepsia partialis continua, increasing left hemiparesis and mental slowing. Death occurred 2 years after the onset of the illness. Lesions were limited to the right cerebral hemisphere. Hypertrophic astrocytosis was diffuse throughout the gray and white matter but was more severe in the deep cortical layers and U fibres, where it was associated with vacuolar changes and capillary proliferation. Sparse perivascular lymphocytic cuffs, rod shaped microglia and microglial nodules were present. No inclusion bodies were found. These clinico-pathologic features were similar to the cases described by Rasmussen. Only five necropsy cases of this rare disease have been reported previously, all in children. The aetiology is unknown.

Symptomatic xanthogranuloma of the choroid plexus of the third ventricle. A new case with ultrastructural study

The clinicopathological findings in a new case of a surgically removed, symptomatic xanthogranuloma of the third ventricle are reported. Ultrastructural study showed that the lining epithelium of the tumor was composed of typical leptomeningeal cells, and that transitional forms from leptomeningeal cells into xanthomatous cells were present in the underlying fibrous capsule. These findings support the hypothesis of a leptomeningeal origin of the foamy cells in the present case. The ten cases reported previously of symptomatic xanthogranuloma of the third ventricle are reviewed. We suggest that xanthogranulomas of the choroid plexus might represent a heterogenous entity arising from xanthomatous changes involving various types of cells.

Extensive form of progressive multifocal leucoencephalopathy associated with laryngeal carcinoma

A case is reported of the rare association between progressive multifocal leucoencephalopathy and carcinoma. A 66-year-old man underwent a laryngectomy for carcinoma. Four years later he developed a local recurrence. Simultaneously there were behavioural disturbances and a left motor neglect followed by dense hemiplegia and coma. The patient died a further 5 months later. Anergy was demonstrated by skin tests. CT scan showed asymmetrical non-enhancing low-density areas in the hemispheric white matter, brain-stem and cerebellum and neuropathological examination confirmed extensive myelin loss with typical papovavirus inclusions in oligodendrocytes identified by electron microscopy.

Leucoencephalopathy with multinucleated giant cells containing human immune deficiency virus-like particles and multiple opportunistic cerebral infections in one patient with AIDS

A 29-year-old homosexual male with AIDS presented with progressive encephalopathy and cytomegalovirus (CMV) pneumonia. Neuropathological examination revealed toxoplasma abscesses in corpus callosum, basal ganglia and cerebellar white matter; demyelinating foci in the parietal white matter, with microscopic changes typical of progressive multifocal leucoencephalopathy and intranuclear papovavirus inclusions in oligodendrocytes; and lesions of subacute encephalitis in the periventricular regions with large cells positive by immunostaining for CMV. Diffuse myelin loss was observed in the cerebral white matter. Multinucleated giant cells were numerous in the demyelinated areas, they were also observed in close relationship with papova, CMV and Toxoplasma lesions. Immunostaining of these cells was positive for histiocyte markers and negative with the leucocyte common antigen monoclonal antibody. Some of them contained virus-like particles measuring around 100 nm similar to human immune deficiency virus (HIV) as observed in human brain.

Almitrine neuropathy. A nerve biopsy study of 8 cases

We report the quantitative and qualitative, light and electron microscopic studies, including teased fiber preparations of nerve biopsies obtained from eight patients, treated with almitrine, presenting with the characteristic association of a sensory peripheral neuropathy with a recent body weight loss. The data were consistent with an axonal damage affecting myelinated fibers, predominantly large ones and to a lesser degree unmyelinated fibers, some degree of segmental demyelination. Marked axonal regeneration was observed when the nerve biopsy was delayed after withdrawal of the drug, Micro-angiopathy secondary to the formation of concentric lamellae from the basement membrane was observed in five patients suffering from chronic hypoxemia. Almitrine is an agonist of the chemoreceptors. The pathogenesis of the toxic neuropathy induced by this compound remains obscure. Clinical features do not fit with a purely hypoxic mechanism at the origin of the neuropathy.

Diffuse subependymal periventricular metastases. Report of three cases

Three clinicopathologic cases with a remarkable pattern of extensive diffuse subependymal periventricular spread of cerebral metastases from solid systemic cancer are reported. Two patients had a small cell carcinoma of the lung. In the third case, the histologic features of the brain metastases were consistent with a neuron-specific enolase-positive, small cell anaplastic carcinoma. Involvement of the choroid plexus and leptomeninges was moderate or absent. Intraparenchymatous nodular metastases were not found except in one case in which rare nodular superficial cortical metastases were present. The clinical data were nonspecific except for orthostatic hypotension, in one patient, which was probably due to the infiltration of the floor of the third and fourth ventricles. Results of the cerebrospinal fluid examination, available in two cases, were normal. The only diagnostic investigation was contrast-enhanced computed tomography scanning.

Orthostatic hypotension from a cerebellar gangliocytoma (Lhermitte-Duclos disease). Case report

A 49-year-old woman presented with orthostatic hypotension. Vertebral angiography and ventriculography revealed a tumor of the left cerebellar hemisphere. Ventriculoperitoneal shunting was followed by complete disappearance of the orthostatic hypotension. The tumor was subsequently removed and microscopic study showed Lhermitte-Duclos disease. Orthostatic hypotension has been rarely reported in association with tumors of the posterior fossa except for those tumors destroying the medullary centers and interrupting the baroreceptor reflex arc. This case is of interest because the tumor was restricted to the cerebellum. The authors have found no previous case in which orthostatic hypotension was a presenting symptom of Lhermitte-Duclos disease.

Post-anoxic delayed encephalopathy with leukoencephalopathy and non-hemorrhagic cerebral amyloid angiopathy

A 74 year-old woman with an early-stage senile dementia developed severe hypertonia and akinetic mutism two weeks after exposure to methane. A CT scan showed a diffuse area of decreased density extending symmetrically into the white matter of both cerebral hemispheres. Neuropathology revealed a senile dementia, Alzheimer's type, with severe non-hemorrhagic cerebral amyloid angiopathy and a diffuse spotty demyelination of the cerebral hemispheres sparing the U fibers, corpus callosum and internal capsules. The close resemblance between Grinker's myelinopathy, secondary to CO exposure or to other non-CO anoxic causes, and the leukoencephalopathy associated with cerebral amyloid angiopathy is emphasized.

Focal perivascular alterations of white matter in herpes simplex encephalitis--a histological and immunocytochemical study

Several cases of human herpes simplex encephalitis treated with Vidarabin have been investigated with the histological and immunocytochemical techniques. Cases with a subacute evolution revealed areas of focal perivascular myelin destruction in the white matter. The distribution of herpes simplex antigen did not show any preferential localization of the virus in perivascular oligoglial cells. In contrast, a spatial and temporal relationship has been found between the appearance of immunoglobulin-bearing cells around the vessels and that of areas of focal perivascular myelin damage. Therefore, it is postulated that the areas of focal destruction of myelin are not related to the cytotoxic effect of the virus but are rather dependent on the immune response of the host.

Infarcts of both inferior parietal lobules with impairment of visually guided eye movements, peripheral visual inattention and optic ataxia

Clinicopathological correlations are reported in a case with bilateral isolated infarcts in the posterior part of the parietal lobes, due to nonbacterial thrombotic endocarditis accompanying pancreatic adenocarcinoma. The initial left-sided infarct induced right visual neglect, impairment of right-beating optokinetic nystagmus (OKN), optic ataxia, Gerstmann's syndrome and apraxia. After the right-sided infarct, which occurred six weeks later, bilateral visuo-oculomotor disturbances were observed, including peripheral visual inattention, disorder of visually guided saccades, severe impairment of foveal smooth pursuit and OKN slow phase. The lesion on the left involved the upper part of the angular gyrus and a part of the adjacent superior parietal lobule (SPL). That on the right involved the supramarginal gyrus and extended posteriorly into the superoanterior extremity of the angular gyrus, into both margins of the adjacent intraparietal sulcus and into a small part of the SPL. As the oculomotor deficits and the peripheral visual inattention were bilateral after the second infarct, they probably resulted from the lesion of homologous areas in both cerebral hemispheres. The zone damaged in common included a small part of the SPL, the superoanterior extremity of the angular gyrus, and the adjacent intraparietal sulcus and a small portion of the subcortical white matter. This restricted cerebral zone could therefore, in man, be implicated both in the control of all visually guided eye movements and in visual attention. It is further suggested that two corticofugal pathways are implicated in visually guided saccades, the first arising from the frontal eye fields and projecting directly onto the premotor structures in the brainstem, the second arising from the posterior parietal cortex (probably mainly the intraparietal sulcus adjacent to the angular gyrus) and including a relay in the superior colliculus before reaching the premotor structures. Lastly, the findings support the hypothesis that optic ataxia results from interruption of direct and/or crossed occipitofrontal pathways coursing in the deep white matter of the parietal lobe.

Thrombosis of a saccular microaneurysm causing cerebral (pontine) lacunae

The authors present the case of a hypertensive patient with a thrombosis of a saccular microaneurysm (SMA) and underlying cerebral (pontine) lacunae. This SMA lay at the junction between the main vessel and two small feeding arteries penetrating into the necrotic territory. Microhemorrhages were observed in and outside the aneurysmal wall. Very sinuous narrow channels of recanalization crossed the thrombosis between the upstream and downstream vessels. The anatomical relationship between the SMA and the lacunae has been histologically demonstrated.

Altered capillary permeability in neurogenic pulmonary oedema

Two cases of fatal neurogenic pulmonary oedema are depicted. The hemodynamic study failed to document any hypertensive crisis or pulmonary hypertension. By contrast, the low values of pulmonary capillary wedge pressures and the high protein concentration in tracheal fluid suggest a pulmonary capillary wall lesion.

Dopaminergic and cholinergic lesions in progressive supranuclear palsy

In 9 patients with progressive supranuclear palsy and in 27 controls, dopamine and homovanillic acid concentrations, choline acetyltransferase (CAT) activity, and the number of [3H]spiperone and [3H]quinuclidinyl benzilate binding sites were measured post mortem in the striatum (caudate nucleus, putamen, and nucleus accumbens), substantia innominata, and frontal cortex. Dopamine and homovanillic acid concentrations were reduced in the caudate nucleus and putamen but not in the nucleus accumbens or frontal cortex, indicating that the nigrostriatal dopaminergic system is lesioned in patients with progressive supranuclear palsy (as in those with Parkinson's disease) but not the mesocortical and mesolimbic dopaminergic systems, which are lesioned in parkinsonian patients. CAT activity and [3H]spiperone binding decreased in parallel fashion in all the structures. In the striatum, this suggests that the cholinergic neurons, which are target cells of the nigrostriatal system, also degenerate in this disease. This might explain the decrease in the number of dopamine receptors as well as the inefficacy of levodopa or anticholinergic therapy in these patients. The decrease in CAT activity in the substantia innominata and the frontal cortex indicates that the innominatocortical cholinergic system is lesioned in patients with progressive supranuclear palsy and may play a role in the intellectual deterioration observed. This lesion is also found in demented patients with Alzheimer's and Parkinson's diseases.

Fatal nonmeningitic Listeria rhombencephalitis. Report of two cases

Two cases of rapidly fatal Listeria rhombencephalitis with normal cerebrospinal fluid (CSF) findings occurred in previously healthy adults. The infection presented with nausea and headache followed by fever and signs of lower cranial nerve dysfunction, without associated meningismus, and progressed to death within four and six days of hospitalization. Because of normal CSF findings (including ventricular fluid in one patient) and negative culture results of both blood and CSF, the diagnosis was not suspected. Listeriosis should be considered early in any febrile patient presenting with signs of brain-stem dysfunction, even if CSF findings are normal.

Bilateral and limited amygdalohippocampal lesions causing a pure amnesic syndrome

A pure amnesic syndrome of 21 months' duration occurred in a 36-year-old man following a transient confusional state. The patient died of Hodgkin's disease. At postmortem examination, bilateral and symmetrical neuronal loss, without inflammatory changes, was restricted to the hippocampus and amygdaloid bodies.