Brain Pathology Case of the Month - May 2001

Contributed by Paul J McCarthy, MD, William P Arend, MD, B K Kleinschmidt-DeMasters, MD
Departments of Pathology (PJM and BKD), Neurology (BKD), and Rheumatology (WPA), University of Colorado Health Sciences Center, Denver, Colorado 80262
Published on line in May 2001


CLINICAL HISTORY:

This 32-year-old woman underwent mastoid surgery for chronic antibiotic-resistant middle ear "infections" one year prior to the present illness. One month prior, she experienced recurrent right ear and neck pain, progressing to upper and lower extremity weakness with unsteady gait and difficulty with ambulation. An initial evaluation included an erythrocyte sedimentation rate (ESR) of 98 (normal = 0-20), a positive c-antineutrophil cytoplasmic antibody (c-ANCA) at a dilution of 1:128, a normal chest X-ray and a normal urinalysis. A magnetic resonance imaging (MRI) scan demonstrated extensive dural enhancement and thickening at the upper cervical level (C1-C4), extending along the clivus, with resultant cord compression at the cranio-cervical junction region. A head computerized tomographic (CT) scan revealed postoperative changes in the right mastoid with partially opacified air cells on both sides without erosion or destruction, consistent with mastoiditis.

Additional serological testing revealed a normochromic/normocytic anemia, negative studies for hepatitis B and C infection, a normal angiotensin-1-converting enzyme level, a nonreactive rapid plasma reagin test for syphilis, and negative results for anti-nuclear antibody (ANA), rheumatoid factors, and anticardiolipin antibodies. Liver function tests (LFTs) were elevated, including both aspartate aminotransferase (AST) and alanine aminotransferase (ALT).

The patient was taken to surgery where a large segment of the thickened dura posteriorly was removed to decompress the cervical spinal cord. Post-operatively, she was treated with high-dose corticosteroids. Use of the immunosuppressive agent methotrexate was precluded by the elevated LFTs, which have persisted and are being further evaluated. An MRI study performed 10 days following her surgery showed the expected post-operative bony changes in the spinous processes, less prominence of the cervical dura, and no evidence of cord compression.

Corticosteroid treatment resulted in a decrease of the ESR to 10, disappearance of c-ANCA antibodies, and resolution of her neurological manifestations within 5 weeks of surgery. Treatment with daily oral cyclophosphamide was subsequently initiated. An MRI study 5 weeks after surgery revealed complete resolution of the dural thickening, no cord compression, and a small area of increased signal in the upper cervical cord possibly related to previous cord injury.

MICROSCOPIC DESCRIPTION

FINAL DIAGNOSIS


International Society of Neuropathology