Gholam H. Pezeshkpour

Myopathy and Cystine Storage in Muscles in a Patient with Nephropathic Cystinosis

NEPHROPATHIC cystinosis is a lysosomal storage disorder characterized by the appearance of renal tubular Fanconis syndrome in the first year of life and by growth retardation, progressive photopho...

AIDS-associated progressive multifocal leukoencephalopathy (PML): comparison to non-AIDS PML with in situ hybridization and immunohistochemistry.

We studied brain sections from 10 patients with the acquired immunodeficiency syndrome (AIDS) and progressive multifocal leukoencephalopathy (PML) by in situ hybridization with a biotin-labeled JC virus (JCV) DNA probe and by immunohistochemistry using antibody against the JCV capsid antigen. We compared the results with brain sections studied in the same fashion from 10 PML patients without AIDS. The pathology of JCV infection in AIDS was similar to non-AIDS PML except for minor differences in degree. AIDS-associated pathologic material showed a greater tendency toward necrosis and a higher density of JCV-infected cells. Replication of JCV was restricted to glial cells in all tissue studied. Bizarre astrocytes were less frequent in the AIDS patients, and perivascular inflammatory cells were more frequent. We could not demonstrate JCV in macrophages or microglial cells known to harbor HIV infection. In situ hyridization with nonradioactive probes serves as a useful technique for the confirmation of PML in AIDS.

Peripheral neuropathy in abetalipoproteinemia

We studied the peripheral neuropathy of three sisters with abetalipoproteinemia. Clinically, a sensory neuropathy progressively increased in severity. There was a diminution in the amplitude of sensory action potentials and a slight-to-moderate slowing in maximum sensory conduction velocity, initially most marked in distal portions of the nerves. Motor conduction was normal, although EMG indicated subclinical signs of partial chronic denervation. The surely nerves showed a decreased number of large fibers (> 7 μm); in the patient with the neuropathy of shortest duration, small fibers and clusters of regenerating fibers indicated regeneration. In the two patients with advanced neuropathy, one-half the segments of teased fibers showed paranodal demyelination. Also, unmyelinated fibers showed evidence of regeneration.

Peripheral neuropathy in hypereosinophilic syndrome

We evaluated seven patients with the hypereosinophilic syndrome (HES) to define the clinicopathologic spectrum of the peripheral neuropathy. Clinically, three had evident polyneuropathy; the others were asymptomatic, although they had electrophysiologic evidence of neuropathy. Nerve conduction studies and EMG were compatible with axonal neuropathy. Morphometry of sural nerves from four patients ranged from normal to marked axonal loss, more prominent in large myelinated fibers. Demyelination was rare, and there was no evidence of vasculitis. Neuropathy may be produced by an eosinophil-derived neurotoxin.

Spinal metastases. A rare mode of presentation of brain tumors

An analysis of more than 18,000 primary central nervous system (CNS) tumors revealed only 18 cases (0.01%) in which dropped spinal metastases had caused the presenting symptoms. This group included 11 males and 7 females in whom there was no history of surgical intervention or irradiation. Primitive neuroectodermal tumors (PNET, medulloblastoma), comprised the largest group (11 patients) followed by high‐grade astrocytomas (anaplastic astrocytoma and glioblastoma) (5 patients). One case each of germinoma and ependymoma were also identified. The clinicopathologic data of these cases, and a brief review of the literature are presented.