MED-17. Nocardial brain abscess mimicking stroke in a patient with Wegener's granulomatosis and hypothyroidism.

We report the case of a 69-year-old man with Wegener's granulomatosis with lung and renal involvement on immunosuppressive therapy for 4 years. He was managed with prednisone and cyclophosphamide up until 2 weeks prior to admission, when cyclophosphamide was changed to azathioprine because of neutropenia. Patient presented with a 1-day complaint of ataxia and slurred speech. Review of systems revealed a 4-month history of headaches, mostly unilateral, progressing over 2 weeks. He denied recent fevers, sinusitis, cough or change in breathing. Admission WBC count was 3.3 K/[mm.sup.3] with 14% band neutrophils; creatinine was 4.2 mg/dl. TSH was later found to be 97.5 IU/ml. Imaging studies included CT of the head, reporting a large area of low density in the right cerebellar hemisphere with local edema and mass effect, consistent with acute cerebellar infarct. MRI revealed a ring-enhancing partially solid, partially cystic mass. Subsequently, a right suboccipital craniectomy revealed purulent material. Empiric antibiotics of vancomycin, metronidazole, fluconazole, and cefepime were initiated. Azathioprine was discontinued and prednisone continued at a lower dose. Cultures revealed Nocardia asteroides, and regimen was changed to imipenem and ceftriaxone. Drainage of abscess followed by treatment with imipenem and ceftriaxone, later changed to oral trimethoprim/sulfamethoxazole, resulted in complete resolution of ataxia and marked improvement in slurred speech and headaches. Abnormalities in cell-mediated immunity are a major risk factor for nocardial infection. This patient was at risk given his chronic granulomatous disease, steroid use and neutropenia. Profound hypothyroidism may also have played a role, as previous studies have proposed that the prolonged deficiency of thyroid hormone may be directly related to the impairment of the cellular immune system. This case signifies the importance of considering infectious etiology in immunocompromised patients who present with neurological events.

L. Thomas. MD, P. Sarna, MD, and H. Cragun, MD. University of Virginia, Roanoke-Salem Program, Roanoke, VA.