Progressive multifocal leukoencephalopathy in individuals with minimal or occult immunosuppression
- 1 Beth Israel Deaconess Medical Center, United States;
- 2 Treasure Coast Infectious Disease Consultants, United States;
- 3 Ghent University Hospital, Belgium
- Correspondence to: I J Koralnik, Dept of Neurology & Division of Viral Path, Beth Israel Deaconess Medical Center, Beth Israel Deaconess Medical Center, E/CLS-1005, Boston, -02215, United States; ikoralni{at}bidmc.harvard.edu
- Received 1 July 2009
- Accepted 24 September 2009
- Published Online First 14 October 2009
Abstract
Background: Progressive multifocal leukoencephalopathy (PML) is a deadly demyelinating disease of the brain, caused by reactivation of the polyomavirus JC (JCV). PML has classically been described in individuals with profound cellular immunosuppression such as patients with AIDS, hematological malignancies, organ transplant recipients or those treated with immunosuppressive or immunomodulatory medications for autoimmune diseases.
Methods and case reports: We describe five HIV seronegative patients with minimal or occult immunosuppression who developed PML including two patients with alcoholic cirrhosis, one with untreated dermatomyositis, and two with idiopathic CD4+ T cell lymphocytopenia. We performed a review of the literature to find similar cases.
Results: We found an additional 33 cases in the literature. Of a total of 38 cases, seven (18.4%) had hepatic cirrhosis, five (13.2%) had renal failure, including one with concomitant hepatic cirrhosis, two (5.2%) were pregnant women, two (5.2%) had concomitant dementia, one (2.6%) had dermatomyositis and 22 (57.9%) had no specific underlying diagnosis. Among these 22, five (22.7%) had low CD4+ T cell counts (0.080-0.294x109/L) and were diagnosed with idiopathic CD4+ lymphocytopenia, and one had borderline CD4+ T cell count of 0.308x109/L.
The outcome was fatal in 27/38 (71.1%) cases within 1.5-120 months (median 8 months) from onset of symptoms, and 3/4 cases who harbored JCV-specific T cells in their peripheral blood had inactive disease with stable neurological deficits after 6-26 months of follow up.
Discussion: These results indicate that PML can occur in patients with minimal or occult immunosuppression and invite us to revisit the generally accepted notion that profound cellular immunosuppression is a prerequisite for the development of PML.
