2009 Southern Regional Meeting Abstracts

Case Report: Introduction: Progressive multifocal leukoencephalopathy (PML) most commonly occurs in patients with HIV but can be seen in other immunodeficiency states. We report PML in the setting of a rare immunodeficiency caused by thymoma (Good’s syndrome).
Case: A 65yo woman presented with rapidly progressive dementia. She was well until 3 months prior when she developed increasing forgetfulness and confusion which progressed. She had not traveled outside of the USA, nor had any tick bites, nor any known exposure to HIV, herpes, syphilis, or TB. Meds: HCTZ, simvastatin, donepezil. She was married and denied alcohol, tobacco, or drug use. No family history of premature dementia, psychiatric, or immunologic disease. Physical exam: stuporous, afebrile, 125/68, O2 sats 94%, no thrush, lymphadenopathy, carotid bruits, or thyromegally; heart, lung, abdomen, extremity, and skin exams all normal. Neuro: strength 4/5, no tremors; DTRs 1+.
Labs: Cr 0.9, Na 140, Ca 9.3, gluc 123, AST/ALT/AP normal, ESR 7, WBC 8.7, RPR non-reactive, ANA and HIV negative, TSH 2.0, B12 1080, IgA 15 (66-436), IgG 582 (791-1643), IgM <25 (43-279). LP: no WBCs or RBCs; neg for bacteria, fungi, and AFB; but PCR-positive for JC virus DNA. CT: 7X7cm mass in the right anterior hemithorax. Biopsy of mass: thymoma without malignant features. Brain MRI: subcortical edema throughout felt to be consistent with PML.
Discussion:
Good’s syndrome is an adult-onset immunodeficiency in the setting of thymoma characterized by hypogammaglobulinemia (IgA, IgG, and IgM) as was seen in our patient. She was also positive for JC virus, a polyomavirus with which 70-90% of all humans are infected. Typically this infection is associated only with a viral syndrome which resolves but in immunocompromised patients the virus can reactivate and replicate within oligodendrocytes causing lysis and rapid demyelination in the brain white matter. This process is termed progressive multifocal leukoencephalopathy and presents with dementia and/or ataxia. While PML is almost exclusively associated with HIV/AIDS, our patient was HIV negative. In our case it appears that Good’s syndrome caused the immunodeficiency which permitted the JC virus to reactivate and cause this fatal case of PML. The authors could find no other case reports of Good’s syndrome in association with PML.