Neurology: Case of the Month

Test Yourself — Patient 21

Progressive Multifocal Leukoencephalopathy (PML)

  1. Which of the following is TRUE regarding PML?
    • [ A ] It is a common condition in the HIV-infected population, occurring in up to 35% of AIDS patients.
    • [ B ] Almost all cases in humans have been associated with the JC virus.
    • [ C ] I.V. drug abusers are more likely to develop PML than any other group of HIV-infected patients.
    • [ D ] Patients who develop PML are generally co-infected with the responsible agent at the time of HIV infection.
    • [ E ] All of the above.
  2. PML has a particular predilection for involving which of the following regions:
    • [ A ] Spinal cord
    • [ B ] Frontal lobe
    • [ C ] Temporal lobe
    • [ D ] Parieto-occipital region
    • [ E ] Medulla oblongata
  3. The agent responsible for PML is:
    • [ A ] A retrovirus similar to HIV-1; patients are frequently co-infected with this agent when infected with HIV-1.
    • [ B ] A prion protein, labeled JC, identical to the agent causing Creutzfeldt-Jakob disease.
    • [ C ] A family of polyomaviruses that cause asymptomatic infection among immuno-competent individuals.
    • [ D ] A recently described gram-negative rod in the same family as the Whipple disease bacillus.
    • [ E ] Completely unknown.
  4. Which of the following statements regarding the pathophysiology of PML is (are) TRUE?
    • [ A ] The responsible virus directly invades and kills neurons to produce disease.
    • [ B ] Cell surface receptors on T lymphocytes and oligodendroglia mediate the tropism for these cell types.
    • [ C ] There is a specific nuclear transcription factor within oligodendroglia that binds JC virus nucleic acids allowing transcription within these cells.
    • [ D ] Abnormal ACE level
    • [ E ] The responsible agent activates the cellular mechanisms responsible for apoptosis, thereby killing the cell.
  5. Which of the following statements regarding parietal lobe function is TRUE?
    • [ A ] Limb-kinetic apraxias result from lesions in the dominant parietal lobe.
    • [ B ] Dressing apraxia may result from either non-dominant or bilateral parietal lobe injury.
    • [ C ] Ideomotor apraxias result from injury to the non-dominant parietal lobe.
    • [ D ] Gerstmann's syndrome results from lesions in the bilateral inferior parietal lobes.
    • [ E ] Constructional apraxia results only from injury to the non-dominant parietal lobe.

 

Email comments: