Biomedical subjects

A Vital

Publications and source records attributed to A Vital.

120 records · Page 7Linked to original sources

PubMedDate not supplied

Myelin modifications in 8 cases of peripheral neuropathy with Waldenström's macroglobulinemia and anti-MAG activity.

Characteristic myelin modifications in patients with IgM monoclonal gammopathy and anti-MAG activity have mainly been studied in cases of undetermined significance, but also exist in cases with indolent Waldenström's macroglobulinemia, i.e., when lymphoplasmocytic infiltration in bone marrow is 15% or more, without any visceral involvement. Since 1983, the authors have examined nerve biopsies from 8 cases with Waldenström's macroglobulinelia by direct immunofluorescence examination on frozen sections and ultrastructural examination. At direct immunofluorescence, fixation of anti-IgM serum on myelinated fibers was present in 7 cases. At ultrastructural examination, a widening of some myelin lamellae at the periphery of a few fibers was visible in 8 cases. A few fibers with hypermyelination were present in 5 cases. In 2 of these 5 cases widening of some myelin lamellae was present in numerous fibers, 88% in one of them. Frequently, there was a major widening of some myelin lamellae with dilated lamellae present in the inner part of the myelin sheath. Certain lamellae were more dilated, up to 50 nm. Occasionally, enlarged lamellae were not compacted with each other. The authors also examined nerve biopsies from 36 patients with IgM monoclonal gammopathy of undetermined significance and anti-MAG activity, but found only one case with major widening of some myelin lamellae. Five other cases with major widening of some myelin lamellae, 4 Waldenström's macroglobulinemia and 1 IgM monoclonal gammopathy of undetermined significance, have been reported. Given that demyelinating neuropathies are far more numerous in cases with IgM monoclonal gammopathy of undetermined significance, it is likely that cases of indolent Waldenström's macroglobulinemia are prone to develop major myelin modifications, possibly due to another mechanism, added to the classic anti-MAG activity.

Aged↗

PubMedDate not supplied

Subacute inflammatory polyneuropathy: two cases with plasmacytoid histiocytes in the endoneurium.

Inflammatory polyneuropathies are mainly known by their acute form, Guillain-Barré syndrome, but there are also chronic cases and all are considered as having an autoimmune mechanism. In each form, peripheral nerve biopsies show scattered macrophages in the endoneurium and in certain cases macrophages invade the Schwann cell cytoplasm and destroy the myelin sheath. In rarer cases there is a primary axonal degeneration. The authors studied two chronic cases, which both exhibited mixed primitive axonal and demyelinating lesions, with peculiar histiocytes in the endoneurium. These rounded cells were characteristically well marked by KP1 but showed well-developed rough endoplasmic reticulum cysternae at ultrastructural examination. Such plasmacytoid histiocytes have mainly been studied in subacute lymphadenopathies and have been only briefly illustrated in a few cases of peripheral neuropathies due to Lyme disease or HIV infection. The two cases reported here had no associated diseases and probably correspond to a peculiar subacute autoimmune reaction.

Adult↗

PubMedDate not supplied

Chorea-acanthocytosis: neuropathology of brain and peripheral nerve.

We report the neuropathological data from a familial case of chorea-acanthocytosis with central and peripheral nervous system involvement. At the age of 34, the patient underwent a peripheral nerve biopsy which was analyzed by light- and electron microscopy. These studies showed a selective reduction in the large diameter myelinated fibre population, with several clusters of regeneration. Remyelinating fibers surrounded by flattened Schwann cell processes were also present. The patient died at the age of 44, and post-mortem macroscopic examination of the brain showed marked atrophy of the caudate. Histological examination of paraffin sections showed almost complete depletion of neurons in the caudate, with severe astrocytic gliosis. The putamen and pallidum were slightly less severely depleted of neurons, but with marked astrocytic gliosis. Diffuse mild gliosis was also evidenced, by immunohistochemistry with anti-GFAP, in the thalamus and subcortical white matter.

Adult↗

PubMedDate not supplied

Leukemic dissemination within a glioblastoma in a patient with chronic lymphoid leukemia.

Metastasis from an extracranial tumor to a primary central nervous system tumor is a rare event, and most reported cases concern metastases to meningiomas. The authors describe the first case of leukemic cell dissemination within a glioblastoma. The patient likely presented a genetic predisposition to multiple neoplasms, and the unusual localization of leukemic cells might be partly related to the characteristic microvascular proliferation in glioblastoma.

Brain↗

PubMedDate not supplied

Subcutaneous tumoral seeding from a glioblastoma following stereotactic biopsy: case report and review of the literature.

Extracranial metastases from glioblastoma are uncommon, likely because short patient survival time prevent them to occur. Most of the few previously reported cases occurred after invasive surgical procedures. We describe a case of glioblastoma with concomitant seeding along the stereotactic biopsy trajectory and subcutaneous metastasis. A 60-year-old woman presented with severe headache. Neuroradiological work-up (including cranial computed tomographic scan and magnetic resonance imaging) showed a heterogeneous hyperdensity, suggestive of malignant glioma, in the left parietal region. A computed tomographic-guided stereotactic biopsy was performed and microscopic examination attested a diagnosis of glioblastoma. Radiotherapy and chemotherapy were administered. Eight months later, the patient presented with a subcutaneous tumor in the left occipital region. A cranial computed tomographic scan revealed a large enhancement of the initial tumor, intracranial tumor seeding along the stereotactic biopsy trajectory, and a subcutaneous tumor. Partial resection of the subcutaneous lesion was performed, and histological examination identified an extracranial metastasis from the glioblastoma. Although uncommon, this observation points to the risk of tumor seeding following stereotactic biopsy, and to the close connection between this intracranial seeding and subcutaneous metastasis.

Biopsy↗

PubMedDate not supplied

Morphological study of the aging human peripheral nerve.

The superficial peroneal nerve from 46 elderly patients was studied by light and electron microscopy. Like most elderly people, these patients displayed evidence of varying degrees of peripheral nervous system dysfunction, but they were not suffering from any disease known to alter the peripheral nerve. A quantitative study showed that myelinated fiber loss predominated in the large diameter group. In the majority of cases, clusters of regenerating myelinated fibers were numerous. On the other hand, Wallerian-like degeneration aspects, segmental demyelination figures and axonal organelle accumulation were relatively rare. Unmyelinated fibers were also notably damaged in most cases. There was moderate reduplication of endoneurial vascular basement membrane.

Aged↗

PubMedDate not supplied

Quantitative, histological and ultrastructural studies of peripheral nerve in arteriosclerotic non-diabetic patients.

The superficial peroneal nerve was taken from 12 arteriosclerotic non-diabetic patients just after amputation of a leg. Preparations of teased fibers were performed in 8 cases. Specimens were studied by light and electron microscopy in all cases. Histograms of myelinated fibers in transverse semi-thin sections showed that depletion of myelinated fibers varied from case to case, with no selective vulnerability in either the large or the small diameter group. There was a dramatic loss of myelinated fibers in only one case. No real nerve infarct was observed. In most cases, regions of Wallerian-like degeneration were prevalent; however, myelino-axonal changes were severe only in a few cases. Axons with organelle aggregates were seen in some cases. Figures of segmental demyelination were not numerous in this series. Unmyelinated fibers were also damaged, and the degree of involvement differed from case to case. Pathological changes observed in this study confirm the relative resistance of peripheral nerve to ischemia.

Aged↗

PubMedDate not supplied

Fabry's disease: an ultrastructural study of muscle and peripheral nerve.

A 9-year-old boy, presented with disseminated angiomatous lesions on the right leg. Ultrastructural examination of muscle and peripheral nerve showed numerous lamellar inclusions characteristic of Fabry's disease in the vessel's walls and perineurial cells. In addition, there were typical lamellar inclusions in some muscle fibers. Large myelinated fibers were reduced in number and some myelinated fibers showed segmental demyelination. Some lipid deposits displaying a lamellar pattern were occasionally seen in a few myelinated and unmyelinated axons. These abnormalities of nervous fibers are uncommon in Fabry's disease.

Child↗

PubMedDate not supplied

[Toxoplasma encephalitis in acquired immunodeficiency syndrome].

Several outbreaks of fatal opportunistic infections and tumors have recently been reported among homosexual men in the United States. Almost all patients had evidence of cellular immunodeficiency. We have studied a French homosexual man with fatal central nervous system toxoplasmosis. Morphological features (light and electron microscopy) of toxoplasma encephalitis are described.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

Lhermitte-Duclos type cerebellum hamartoma and Cowden disease.

A Lhermitte-Duclos type cerebellum hamartoma is reported in a woman with a diffuse hamartomatous condition involving the breast, thyroid, colon, skin, and kidney. The family history demonstrated the autosomal dominant transmission of this hamartomatous syndrome, and indicated the diagnosis of Cowden disease. This observation supports the recent hypothesis of Lhermitte-Duclos disease associated with Cowden disease as being a single phakomatosis.

Axons↗

PubMedDate not supplied

Immunoelectron identification of endoneurial IgM deposits in four patients with Waldenström's macroglobulinemia: a specific ultrastructural pattern related to the presence of cryoglobulin in one case.

In four patients with Waldenström's macroglobulinemia and peripheral neuropathy, direct immunofluorescence on a peripheral nerve biopsy revealed the presence of IgM deposits in the endoneurium. At ultrastructural examination, these endoneurial deposits were granulo-fibrillar in three cases, and tubular in the fourth, in whom a cryoglobulin was evidenced in the serum. In each case the endoneurial deposits were also identified as IgM by post-embedding immunoelectron microscopy with good preservation of the characteristic ultrastructural details.

Aged↗

PubMedDate not supplied

Pathologic correlations between ocular and cerebral lesions in 36 AIDS patients.

The eyes and brain have rarely been studied simultaneously in AIDS patients. We have examined both the eyes and brain of 36 patients autopsied these past 3 years. Ten cases had concomitant involvement of eyes and brain by the same pathology: cryptococcus neoformans in 1, aspergillus in another, cytomegalovirus (CMV) infection in 5, and B cell lymphomas in 2 (1 patient had the last 2 disorders associated). One patient presented pericapillary microhemorrhages in the retina of the left ocular globe as well as in the right occipital lobe. Six other patients had isolated CMV retinopathy and 4 others had B cell cerebral lymphomas. Eleven patients with foci of cerebral toxoplasmosis did not have visible cysts of toxoplasma gondii in their retina, in agreement with the other series devoted to the concomitant study of the eyes and brain in AIDS patients. On the other hand, their simultaneous involvement in an AIDS patient must first point to CMV infection.

AIDS Dementia Complex↗