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Progressive Multifocal Leukoencephalopathy in a HIV Negative, Immunocompetent Patient
1Columbia College of Physicians and Surgeons, Columbia University Medical Center, 161 Fort Washington Avenue, New York, NY 10032, USA.
Abstract:
Progressive multifocal leukoencephalopathy (PML) is a rare demyelinating disease most common in immunodeficient patients. It occurs due to reactivation of the John Cunningham Virus (JCV) and carries a poor prognosis, with a median life expectancy of 6 months. We report a case of a 66-year-old man with a history of HCV related cirrhosis (HCV) and hepatocellular carcinoma (HCC) who was found to have PML in the setting of a negative viral load in the CSF and a CD4+ >200. He initially presented with two weeks of mild confusion and word-finding difficulty concerning for hepatic encephalopathy. An MRI was notable for extensive T2/FLAIR hyperintensity signal in the left temporal lobe. Brain biopsy was positive for JCV. PML is rare in immunocompetent individuals, especially in the setting of a negative viral load. It is possible, however, that transient states of immunosuppression may have been responsible in this case. Although viral load was reported as negative, virus may still have been detected but was below the quantifiable threshold. It is important for clinicians to note that a negative result does not necessarily exclude the possibility of PML, and care should be taken to review lab values on viral load in closer detail.
Insights
Progressive multifocal leukoencephalopathy (PML) is a rare brain disease. This case highlights PML diagnosis in an immunocompetent patient with a negative viral load, emphasizing careful lab review.
Area of Science:
- Neurology
- Virology
- Immunology
Background:
- Progressive multifocal leukoencephalopathy (PML) is a rare, fatal demyelinating disease caused by John Cunningham Virus (JCV) reactivation.
- PML predominantly affects individuals with compromised immune systems, carrying a median survival of only six months.
Purpose of the Study:
- To report a rare case of PML in a patient with a seemingly intact immune system.
- To emphasize the diagnostic challenges posed by PML in immunocompetent individuals, particularly with negative viral loads.
Main Methods:
- Case report of a 66-year-old male with HCV-related cirrhosis and HCC.
- Clinical presentation included confusion and word-finding difficulties, initially suggestive of hepatic encephalopathy.
- Diagnostic workup involved MRI revealing extensive T2/FLAIR hyperintensities and subsequent brain biopsy confirming JCV.
Main Results:
- The patient presented with neurological symptoms but had a CD4+ count >200 and negative JCV viral load in cerebrospinal fluid (CSF).
- Brain biopsy confirmed PML, despite the absence of detectable viral load in CSF.
- This case challenges the typical presentation of PML in immunocompetent individuals.
Conclusions:
- PML can occur in individuals considered immunocompetent, potentially due to transient immunosuppression.
- A negative JCV viral load in CSF does not exclude PML diagnosis.
- Clinicians must maintain a high index of suspicion and meticulously review laboratory data, including viral load thresholds, when diagnosing PML.
