Biopsy-proven PML in an HIV-negative patient with discoid lupus: Failure to detect JC virus in CSF.

We present a case of a 58-year-old man with a history of severe discoid lupus erythematosus and acute encephalopathy and incoordination. Antinuclear antibody testing was weakly positive but all other laboratory tests for systemic lupus erythematosus were negative and serum quantitative immunoglobulins and lymphocytes were normal. MRI brain showed T2/FLAIR hyperintensities within the bilateral parietal and temporal lobes with involvement of subcortical U fibers. CSF PCR was negative for varicella-zoster virus, herpes simplex, JCV and BK virus. However, JCV antibody index was elevated (3.88; reference: < 0.2). Right parietal brain biopsy was consistent with JCV infection and diagnostic of progressive multifocal leukoencephalopathy (PML). To the best of our knowledge, this is the first reported case of PML in a patient with discoid lupus without other traditional risk factors for the disease and highlights the need for clinical vigilance in this patient population.

Dysarthria and Stutter as Presenting Symptoms of Late-Onset Tay-Sachs Disease in Three Siblings.

Late-onset Tay-Sachs disease (LOTS) is a rare autosomal-recessive genetic disorder caused by insufficient activity of the lysosomal enzyme, beta-hexosaminidase A, resulting in intracellular accumulation of gangliosides in the central nervous system. Clinical manifestations can include unsteadiness in gait, muscle weakness, cognitive dysfunction, psychiatric disturbance, and dysarthric speech. The variable presentation of these symptoms, combined with the late onset of the disease, often results in misdiagnosis. We present video of 3 sibling cases of LOTS in which a dysarthric stutter was the sole presenting symptom in order to better characterize the phenotype of this disease.