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Biomedical subjects

J Mikol

Publications and source records attributed to J Mikol.

At least 73 records · Page 4Linked to original sources

Intraforaminal neurinoma in the lumbosacral region.

A series of 12 patients with intraforaminal neurinomas in the lumbosacral space was reviewed. Our classification according to tumor extension relative to the affected root into intradural intra-arachnoid, intraforaminal extra-arachnoid, and extraforaminal types was useful in determining the best surgical approach to achieve root preservation and minimal postoperative deficits. Where sacrifice of roots was unavoidable, surprisingly few neurological deficits occurred.

Adult↗

[Ablation of the internal limiting membrane, macular unfolding and visual outcome in surgery of idiopathic epimacular membranes].

The files of 40 patients operated on for epimacular membranes were reviewed in order to correlate the functional and anatomical results with the presence or absence of internal limiting membrane on histological specimens. Only the eyes with idiopathic membranes were considered for the study. Visual acuity and fluorescein angiography were obtained preoperatively and at the 6 months postoperative visit. The surface of the posterior pole was measured on fluorescein angiogram pre and postoperatively by computerized image analysis. Light microscopy looked for the presence of significant segments of internal limiting membrane. In 28 cases (group 1) long segments of internal limiting membrane were adherent to the epimacular membrane and in 12 cases (group 2) no internal limiting membrane fragments or only small fragments were present. Mean postoperative visual acuity was the same in the two groups; 64% of eyes from group I and 50% from group 2 had visual acuity superior or equal to 0.5 (NS). Image analysis showed that the posterior pole surface area increased by 25% in group 1 but only by 15% in group 2 (p < 0.025). Internal limiting membrane ablation does not preclude good visual recovery and is correlated with improved unfolding of the posterior pole.

Fluorescein Angiography↗

[Report of a case of rhabdomyosarcoma of the central nervous system. Histologic, immunohistochemical and ultrastructural study].

A patient, aged 26, had a large parietal tumor, clinically revealed by intracranial hypertension and left sized paresthesia. Removal of tumor was followed by a rapid recurrence. Rhabdomyosarcoma was diagnosed on the second surgical specimen. These tumors are rare in the central nervous system. They occur mostly, though not exclusively, in young adults. Their prognosis is poor and their histogenesis is still unclear.

Adult↗

[Cerebral glioblastoma: a new complication of HIV-1 infection].

A new case of supratentorial malignant glioma is reported in an HIV-1 infected male homosexual. Tumours of the nervous system account for only 5 to 10 percent of neurological complications of AIDS, and most of them are lymphomas or metastases from Kaposi's sarcomas. In fact, HIV-1 is a neurotropic lentivirus, not transforming by definition. Our patient had a frontal tumoral syndrome resistant to the conventional anti-toxoplasmic treatment. Pathological examination of a tumoral fragment obtained by stereotactic biopsy showed that according to the WHO criteria the tumour was a glioblastoma. The mechanism through which HIV infection results in malignant transformation of astrocytes is conjectural. There is no consensus on whether the virus is located in glial cells, but the transgenic animal technique suggests that the tat gene might play a certain role. Other hypotheses concerning the indirect neurotoxicity of HIV have been put forward, notably that of viral coinfection with viruses of the papova group.

Acquired Immunodeficiency Syndrome↗

Allelic loss on chromosome 22 correlates with histopathological predictors of recurrence of meningiomas.

Meningiomas are common tumors of the nervous system. Although usually benign, they may exhibit variable degrees of aggressiveness. Their probability of recurrence after subtotal resection has been correlated with several histological parameters. Independently, a loss of chromosome 22, as evidenced either by cytogenetics or by somatic loss of alleles, has been observed in about half of the cases studied. In 34 meningiomas we have examined the relationship between loss of chromosome 22 alleles and 6 histological predictors of recurrence. Significant correlations were found for 3 of these, i.e. prominent nucleoli (p less than 0.002), microscope count of mitoses (p less than 0.05) and nuclear pleomorphism (p less than 0.02). Correlation with the other 3, i.e. sheeting of cells, vascularity and micronecrosis, did not reach significance. Total tumor score, defined by the sum of the individual scores for these 6 parameters, was strongly correlated to allelic loss (p less than 0.0001). Thus, the loss of chromosome 22 alleles, which possibly contribute to the inactivation of tumor-suppressor gene(s), might be a potent genetic marker of the aggressiveness of meningiomas.

Aneuploidy↗

[AIDS-related progressive multifocal leukoencephalopathy limited to U fibers, responsible for subacute encephalopathy with normal CT scan findings].

A 41-year-old male homosexual with AIDS was hospitalized for temperature elevation to 40 degrees C with confusion. Neurologic evaluation found psychomotor slowing and temporospatial disorientation with no focal signs. The CD4 count was 100/mm3. CSF analysis and the CT scan were normal. Despite antiviral treatment the patient died fifteen days after admission. Gross appearance of the brain was normal. Histologic examination disclosed multiple, small foci of demyelination characteristic of progressive multifocal leukoencephalopathy. These foci were disseminated among the U fibers. In situ hybridization and immunocytochemical studies demonstrated papovavirus particles in oligodendrocytes and a few astrocytes. This case shows that papovavirus infection in AIDS patients may be responsible for a diffuse febrile encephalopathy with normal CT scan findings and a rapidly progressive course.

AIDS-Related Opportunistic Infections↗

Granulomatous angiitis and cerebral amyloid angiopathy presenting as a mass lesion.

A woman, who presented with clinical and radiological signs of a right temporal mass suggestive of a brain tumour, was found to have granulomatous angiitis associated with cerebral amyloid angiopathy; the diagnosis was confirmed by biopsy. She is still well 13 years after excision of the lesion. The association of granulomatous angiitis and cerebral amyloid angiopathy constitutes a peculiar variety of central nervous system micro-angiopathy. Only a few similar cases have been described.

Amyloidosis↗

Cerebrotendinous xanthomatosis: treatments with simvastatin, lovastatin, and chenodeoxycholic acid in 3 siblings.

We report 3 sisters treated for cerebrotendinous xanthomatosis. We treated one, with a severe neurologic form of the illness, with chenodeoxycholic acid, then lovastatin and simvastatin. These drugs had different efficacy and tolerance, but induced no clinical improvement. Her sisters, without neurologic symptoms, received chenodeoxycholic acid, which normalized the cholestanol level. Optimal treatment of this illness must begin before there is significant clinical symptomatology.

Adult↗

Primary lymphoma of the central nervous system. An unresolved therapeutic problem.

From January 1979 to December 1987, 35 cases of primary central nervous system lymphoma (CNS-L) were treated. We recently reviewed these cases focusing on treatment results, treatment modalities, and radiotherapy (RT) or chemotherapy-radiotherapy (CT-RT). Variables such as age, risk factors, presenting symptoms, and histologic condition (all were high-grade or intermediate-grade non-Hodgkin's lymphomas [NHL]) and radiologic data were similar to those of series reported previously. The median survival time was 36 months (+/- 0.2 months) and the disease-free survival (DFS) time was 16 months (+/- 0.12 months). Twelve of 32 patients evaluable for treatment results experienced a recurrence (all but one occurred in the CNS). The DFS rate was 70% for the CT-RT group and 50% for the RT group (median follow-up time, 24 months). Therapeutic results in CNS-L are discussed with special emphasis on a putative role of CT in the management of this rare type of tumor.

Adolescent↗

Neuronal intranuclear inclusion disease in a child: diagnosis by rectal biopsy.

A 15-year-old boy presented with progressive pyramidal and extrapyramidal signs, anterior horn cell dysfunction, and behavioral disturbances suggesting a diagnosis of neuronal intranuclear inclusion disease. The diagnosis was confirmed by examination of a rectal biopsy specimen that showed typical intranuclear inclusions in the neurons of the myenteric plexus. Diagnosis of neuronal intranuclear inclusion disease during life appears to be possible.

Adolescent↗

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.

Acquired Immunodeficiency Syndrome↗

Stereotactic biopsy diagnosis of primary non-Hodgkin's lymphoma of the central nervous system. A histological and immunohistochemical study.

We report 29 cases of primary non-Hodgkin lymphomas (NHL) of the Central Nervous System (CNS), 26 of which were diagnosed by stereotactic biopsy and 3 by autopsy. In seven cases the patients were affected by AIDS. Histological examination of this series revealed 15 cases of immunoblastic lymphoma, 12 cases of centroblastic lymphoma, 1 case of lymphoplasmacytic immunocytoma and 1 case of unclassified high grade lymphoma. By immunohistochemistry the B-cell origin of lymphoma cells was demonstrated in 28/29 cases. Eight cases were assigned to the B-cell lineage by demonstration of monotypic surface or cytoplasmic immunoglobulin or of the B-cell phenotype CD22+, CD2-, CD3-, CD5-. In twenty cases the B-cell nature of lymphoma was identified by positivity with two or more anti-B monoclonal antibodies (LN1LN2MB2) and negativity by the anti-T monoclonal antibody UCHL1. The histologically unclassified case was a peripheral T-NHL (CD1-, CD2+, CD3-, CD5+, CD22-). We conclude that histological and immunohistological evaluation of stereotactic biopsy specimens provides sufficient information for diagnosis and phenotypic characterization of primary NHL of the CNS. These lymphomas exhibit important predominance of high-grade malignancy histological types and are nearly always B-cell derived. In addition, we provide further evidence that the panel of monoclonal antibodies LN1, LN2, MB2, and UCHL1 is useful for immunophenotypic characterization of brain lymphomas when only paraffin embedded stereotactic biopsy tissue is available.

Adult↗

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.

AIDS-Related Complex↗

Esthesioneuroblastoma with intracranial extension.

The authors present five cases of olfactory neuroblastoma with intracranial extension operated on in the Department of Neurosurgery in collaboration with otorhinolaryngologists. This tumor is most frequently reported as growing inside the nasal cavities, and it can extend to the paranasal sinuses. Cases presenting initially as intracranial tumors have been infrequently reported. At present, histological diagnosis of this tumor is aided by the use of electron microscopy and immunocytochemistry. Total resection combined with radiation therapy remains the most satisfactory treatment.

Adolescent↗

The juvenile and chronic forms of GM2 gangliosidosis: clinical and enzymatic heterogeneity.

We report the cases of 5 patients from 2 sibships with the "adult" or chronic form of GM2 gangliosidosis and 2 patients from another sibship with the juvenile form. We demonstrated hexosaminidase A deficiency in all cases but in 1 sibship the enzymatic profile was identical to that in Tay-Sachs disease, whereas in the remaining 2 families it was that of the B1 variant. There was no correlation between the clinical features and the enzymatic profile. Hexosaminidase A deficiency should be considered in unexplained progressive neurologic disorders of childhood and adolescence, including isolated dementia. EMG evidence of anterior horn cell involvement in association with neurologic or cognitive deterioration may be a diagnostic clue in the juvenile forms.

Adolescent↗

Severe encephalitis resulting from coinfections with HIV and JC virus.

We observed 3 cases of progressive multifocal leukoencephalopathy (PML) among frozen CNS samples obtained at autopsy from 102 adult AIDS patients. In 2 patients, PML was associated with severe HIV encephalitis. In those 2 cases, the areas of extensive JC-induced demyelination were massively infiltrated by HIV infected macrophages/microglial cells with evidence for localized increase of HIV encephalitis in PML lesions. Using immunohistochemistry and in situ hybridization, we demonstrated that each virus infects, in a latent or productive fashion, different CNS cell populations. Therefore, the extension of HIV encephalitis could not be related to an intracellular transactivation of 1 virus by the other. However, the results are consistent with dissemination of viral infection by the recruitment of HIV-infected macrophages to damaged areas of the brain. This phenomenon might be generalized to other pathogens that are frequently associated with HIV CNS infection. Early detection and treatment of opportunistic CNS lesions could be important to prevent extension of HIV encephalitis.

AIDS Dementia Complex↗

MRI pattern of progressive multifocal leukoencephalopathy (PML) in AIDS. Pathological correlations.

Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease which occurs in immunodepressed subjects and is particularly frequent in AIDS. Some authors having drawn attention to the protean aspect of the disease and claimed that AIDS may lose its basic characteristics and affect the grey matter as well as the white matter, we reviewed a series of 8 patients who had been biopsied and/or autopsied and had been examined at least once by MRI. In this series, contrary to what is regularly observed in toxoplasmic abscesses we did not find any lesion of the grey matter or any mass effect. On the other hand, we confirmed that PLM is not multifocal in all cases and that it course may be interrupted by prolonged remissions. The MRI criteria for PML therefore are reliable, provided multiple T2-weighted slices in coronal plane are performed, clearly showing the anatomy of the white fibres affected. However, it must be borne in mind that HIV-infected patients often have other associated brain pathologies, especially when the immune deficiency increases.

Acquired Immunodeficiency Syndrome↗