Dementia and motor neuron disease: morphometric, biochemical, and Golgi studies

In three patients dementia without neurofibrillary tangles or Pick bodies antedated amyotrophy by several years. The motor neuron disorder in two patients was characterized by terminal bulbar symptoms; in one it was similar to classic amyotrophic lateral sclerosis. In two patients, quantitative studies of selected regions of the cortex using a computerized image analyzer disclosed, as in patients with senile dementia of Alzheimer type, a marked reduction in the number of neurons, especially those larger than 90 mu 2. The findings differed from those in Alzheimer dementia, however, in that the cells in the substantia innominata were not reduced and the levels of choline acetyltransferase and somatostatin-like immunoreactivity, determined in one patient, were within normal limits. A variable degree of sponginess of the upper layers of the cortex was attributed to attrition of pyramidal cell dendrites, observed in the one patient in whom Golgi study was successful. Because of severe degeneration of the substantia nigra in all three, the disease in these patients may represent a subset of motor neuron disease or a multisystem atrophy.

Motor neuron disease: a paraneoplastic process associated with anti-hu antibody and small-cell lung carcinoma

Although isolated lower motor neuron disease has been reported as a paraneoplastic complication, it has not been previously described, in association with anti-Hu antibody. We report a 51-year-old man in whom weakness heralded the presence of a small-cell cancer of the lung. His neurological disorder was characterized by an unremitting progression of limb, neck, and chest wall weakness and wasting that commenced and remained predominant in the upper limbs. Electrophysiological studies demonstrated widespread denervation and examination of a muscle biopsy specimen showed evidence of acute and chronic denervation. High titers of anti-Hu antibody were detected in the serum and cerebrospinal fluid. Neither objective measures of strength nor titers of anti-Hu antibody responded to corticosteroids, cyclophosphamide, intravenous immunoglobulins, or plasmapheresis. Death from the complications of motor neuron disease ensued 23 months after the onset of weakness. Autopsy revealed tumor in the lung and on pleural and peritoneal surfaces. There was a loss of anterior horn cells in the spinal cord. Despite the absence of symptomatic cerebellar disease, a decrease in the number of Purkinje cells was also detected.

Brainstem glioma: clinical manifestations of meningeal gliomatosis

Brainstem gliomas of children are variably malignant tumors that rarely have been reported to produce subarachnoid dissemination. Nevertheless, during a two-year period, 5 of 15 such patients treated by us developed symptoms of leptomeningeal metastases. The diagnosis of an anaplastic astrocytoma with meningeal gliomatosis was confirmed postmortem in all 5. In 3 children, meningeal symptoms preceded other signs of posterior fossa recurrence. Symptoms of meningeal gliomatosis included local or radiating back pain (5 patients), segmental weakness (3), paresthesia (2), and incontinence (2). Myelography, performed in 4 patients, was the most useful diagnostic technique, disclosing multiple intradural filling defects or a high degree of block in 3 patients. Although the cerebrospinal fluid was abnormal in all 4 examined patients, in only 1 were malignant cells detected. Prolonged survival, which appears to predispose to dissemination of adult malignant gliomas, was not an apparent factor in our patients.

Formaldehyde: a question of cancer policy?

This article describes recent events concerning the assessment and regulation of formaldehyde, and evaluates the scientific data pertaining to the carcinogenicity of this substance in the context of established cancer policies and guidelines. The conclusion is that recent decisions by several federal agencies to defer action to limit human exposure to formaldehyde may be a "test case" for a new, less protective policy concerning the regulation of carcinogenic substances in general.

HIV-1 heterogeneity and cytokines. Neuropathogenesis

Mild manifestations (HIV-1 associated minor cognitive/motor disorder), severe manifestations (HIV-1 associated dementia complex and HIV-1 associated myelopathy), and sensory neuropathy are consequences of HIV-1 infection. Our goal is to elucidate the role of HIV-1 in the complications of AIDS including cytokine immunopathology and HIV-1 DNA sequence variants. We have examined the brain and sensory ganglia from 60 AIDS patients and 20 seronegative controls using PCR, DNA sequencing of the HIV-1 envelope protein (env), in situ hybridization (ISH), and immunohistochemistry (IHC). Using our combined ISH-IHC technique, we could identify different types of cells and HIV-1 simultaneously in cryostat and paraffin sections. We found HIV-1 predominantly in macrophage/microglia in brain. In dorsal root ganglia (DRG) we found rare macrophages infected with HIV-1 and neurons and interstitial cells (including macrophages) which were apoptotic. Cytokines were detected in mononuclear and endothelial cells near neurons. We achieved single copy sensitivity detecting HIV-1 in nervous tissue using nested PCR. We sequenced HIV-1, DNA from 3 intravenous drug users (IDUs): from brain, CSF, and blood. PCR amplification was followed by cloning and then sequencing the HIV-1 insert: V1-V5 regions of the envelope (env) gene. We found that the env genes had increased sequence variation compared to the literature, cDNA sequences derived from RNA were less heterogeneous than clones derived from DNA from the same specimens, clones derived from brain are more closely related (show restricted heterogeneity) compared to clones from blood and CSF from the same patients. Patient 149 clones we examined to date did not correspond to any of the designated subtypes (A-F) of HIV-1 based on the DNA sequences of the C2-V3 regions. Finally, the HIV-1 RNA produced in these tissues is derived from a minority of DNA clones. Although HIV-1 infected macrophages are not entirely responsible for pathology in the brain and less so in sensory ganglia, some of the products of infection, cytokines, are more widespread in these tissues. Furthermore, HIV-1 strains infecting the brain appear to exhibit restricted heterogeneity compared to autologous CSF and blood and these strains may be associated with cytokines and pathology. HIV-1 strains that infect nervous tissue and cytokines produced in this tissue may effect neuropathogenesis, in vivo, in spite of low levels of local HIV-1 infection. We attempt to delineate, here, common sequence variations in HIV-1 isolates in the hope of developing future therapeutic strategies.

Walker-Warburg syndrome: neurologic features and muscle membrane structure

Walker-Warburg syndrome is an autosomal-recessive genetic disorder characterized by congenital muscular dystrophy in association with complex developmental abnormalities of the central nervous system and the eyes. Two patients with Walker-Warburg syndrome are presented to demonstrate clinical variability. Previously unreported pathologic findings involving heart, muscle, spinal cord, and gall bladder are described, and the literature is reviewed. Histopathologic studies of the muscle membrane protein network in both Walker-Warburg syndrome patients reveal a decreased immunostaining for laminin alpha2 and beta-dystroglycan. The clinical, histologic, and biochemical variability in Walker-Warburg patients may reflect heterogeneity.

Inhibition of acute experimental allergic encephalomyelitis in mice by colchicine

Colchicine was found to inhibit the clinical and histopathological manifestations of monophasic experimental allergic encephalomyelitis in mice. For inhibition of actively induced disease, inoculation of colchicine at the time of encephalitogenic challenge was found to be most effective. In adoptive transfer experiments, lymph node cells (LNC) from colchicine treated donors failed to transfer the disease. Additionally, colchicine treatment of recipients receiving an otherwise disease-inducing level of sensitized LNC prevented the development of disease. Experiments involving delayed-type hypersensitivity expression support an inhibitory role for the drug on event(s) of the efferent pathway of the cellular immune response.

Induction of chronic neurologic disease in mice with canine distemper virus

The capacity of a mouse-adapted strain of canine distemper virus (CDV) to induce central nervous system (CNS) disease in weanling mice was investigated. Lethality of infection was found to be mouse-strain-dependent. In sensitive strains, an acute meningoencephalomyelitis developed. Brain tissue from acutely ill animals demonstrated numerous foci of viral antigen, and extracts yielded infectious virus. Mice of resistant strains, notably the SJL strain, survived the effects of acute infection, appeared well for several weeks, and then began to develop signs of subacute CNS disease. Preliminary histopathologic examination of brain and cord from acutely ill animals revealed prominent perivascular mononuclear cell infiltrates, mononuclear cell meningitis, and gliosis. These features were also found in the subacute disease, where, however, the lesions were less severe. Also, in the latter, virus antigen could not be demonstrated. The results indicate that CDV infection of mice may provide a promising model system for the study of virus-induced chronic CNS disease.

Diabetes insipidus after carbon monoxide poisoning and smoke inhalation

Diabetes insipidus was encountered in a 58-year-old woman after injury in an closed space fire. Carboxyhemoglobin measured 26% after 30 minutes of assisted ventilation with an FIO2 of 1.0. The failure of antidiuretic hormone was a sign of a diffuse cerebral insult caused by carbon monoxide poisoning. The hormonal deficit was easily corrected by exogenous vasopressin. Mortality was related to the cerebral lesion.

Heterogeneity of Macrophage and T Cell Subpopulations in Peripheral Nerves from HIV Infected Individuals

GOAL

To determine the heterogeneity of surface marker expression of macrophages in peripheral nerve of patients who died with AIDS.

BACKGROUND

Peripheral neuropathy occurs in 20%-40% of AIDS patients. There is evidence that activated macrophages may be involved in the neural damage associated with HIV-1 infection. We studied the expression of macrophage surface markers CD14, CD11c, CD68, and HLA-DR and also T cell surface markers CD3, CD4, and CD8 in peripheral nerves of AIDS patients.

METHODS

Three levels of peripheral nerves (sciatic, tibial, or sural) were examined from a limited number of subjects consisting of 4 HIV-seropositive and 5 HIV-seronegative individuals. Standard immunohistochemical technique utilized alkaline phosphatase conjugate and fuchsin substrate.

RESULTS

Surface antigen expression was significantly (p < .0025 increased in HIV-positive tissues compared with HIV-negative controls for CD14 and CD4 in sciatic nerves, CD68 and CD4 in tibial nerves, and CD68 in sural nerves. There were trends for increased expression of HLA-DR, CD3, and CD8 in sciatic nerves, CD11c and CD14 in tibial nerves, and CD14, HLA-DR, and CD4 in sural nerves in HIV-positive tissues compared with HIV-negative controls.

CONCLUSION

During the course of AIDS there may be an involvement of all three levels of peripheral nerves suggesting that HIV-related neuropathy is a multifocal process.

Neuronal ceroid lipofuscinosis with hypergonadotropic hypogonadism

A case of adolescent-onset neuronal ceroid lipofuscinosis presenting with chorea and evidencing pyramidal and cerebellar dysfunction as well as hypergonadotropic hypogonadism is reported. In this patient, primary ovarian failure may be due to accumulation of ceroid in the ovaries.

Sensitivity and specificity of three clinical criteria for dementia with Lewy bodies in an autopsy-verified sample

OBJECTIVE

To evaluate the sensitivity and specificity of the clinical features of three published diagnostic criteria for diffuse Lewy body disease (DLBD) using autopsy-confirmed Alzheimer's (AD), DLBD and AD+DLBD (mixed) dementia cases.

DESIGN

Retrospective chart review of an autopsy series of 56 patients selected from the State of Florida Brain Bank on the basis of a pathological diagnosis of either pure AD, DLBD (pure and common forms) or AD+DLBD (mixed) dementia. Clinical features were assessed by three raters blind to the pathological diagnosis.

RESULTS

The existing criteria for a clinical diagnosis of DLBD were highly specific (90-100%) but not very sensitive (49-63%) in the differential diagnosis of DLBD versus AD; sensitivity did improve (61-74%) when mixed AD+DLBD cases were eliminated. Clinical features that occur more frequently in DLBD than in AD were unspecified hallucinations, unspecified EPS, fluctuating course and rapid progression. Post-hoc analysis also indicated that hallucinations and EPS were more common early in the disease course of DLBD than in AD. Empirically derived criteria, formulated using the most prevalent clinical features, demonstrated sensitivity values of 57-96% for pure forms and 43-91% for mixed forms.

CONCLUSIONS

This study demonstrated that additional improvements in the established criteria for DLBD are needed. Our empirically derived criteria enhanced the distinction of DLBD from AD while allowing the clinician the choice of maximizing sensitivity with acceptable specificity, and vice versa.