PROGRESSIVE MULTIFOCAL LEUKOENCEPHALOPATHY

ALTERNATE NAMES

PML

DESCRIPTION

Progressive Multifocal Leukoencephalopathy (PML) is a fatal disease of the brain that can occur in individuals with immunocompromised conditions such as AIDS, transplant patients, individuals undergoing chronic corticosteroid or immunosuppressive therapy; and individuals with cancer such as Hodgkin’s disease, lymphoma and sarcoidosis. The disease is caused by the John Cunningham polyomavirus (also known as polyomavirus JC or JC virus) which results in the loss of white matter (myelin) in multiple areas of the brain. Without the protection of myelin, nerve signals can’t travel successfully from the brain to the rest of the body. Typical symptoms associated with PML are diverse, since they are related to the location and amount of damage in the brain, and evolve over the course of several days to several weeks.  The most prominent symptoms are clumsiness; progressive weakness; and visual, speech, and sometimes, personality changes.   

DIAGNOSTIC

TESTING, PHYSICAL FINDINGS, AND ICD-9-CM CODING

A positive diagnosis of PML can be made with a brain biopsy and by observing the progression of the disease. An MRI scan can determine if there are any white matter lesions and a spinal tap can detect the presence of the JC virus. Lab testing may include: cytology exam of the urine. EEG and CT scans are also diagnostic of the disease.

ICD-9: 046.3 Progressive multifocal leukoencephalopathy

ONSET AND PROGRESSION

The progression of deficits leads to life-threatening disability and death over weeks to months. The mortality rates for those with HIV-PML have fallen dramatically from approximately 90 percent to around 50 percent according to most reports. For non-AIDS individuals with PML, the prognosis remains grim; the disease usually lasts for months and 80 percent die within the first 6 months, although spontaneous improvement has been reported. Those who survive PML can be left with severe neurological disabilities.

TREATMENT

Currently, the best available therapy is reversal of the immune-deficient state. This can sometimes be accomplished by alteration of chemotherapy or immunosuppression (even if it means losing non-vital transplanted organs). In the case of HIV-associated PML, immediately beginning anti-retroviral therapy will benefit most individuals.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation: Clinical examination that includes a description of findings, urine analysis, CT scan, EEG, and MRI. HIV testing.

Suggested Listings for Evaluation:

DETERMINATION

LISTING

Meets Listing

14.11

114.11

Medical Equals