MICROSCOPIC DESCRIPTION:
The section shows a small fragment of loose fibrous tissue which has undergone partial coagulative necrosis. No organisms are identified. There are no granulomas and no evidence of tumour is seen.
The sections of each of the two specimens show fragments of spinal cord white matter and single and small aggregates of neuronal cells, several of which have undergone chromatolysis. There is patchy coagulative necrosis and patchy dense infiltration by lymphoid cells and monocyte-derived macrophages. The lymphoid cells are predominantly CD8+ T cells with lesser numbers of CD4+ T cells and CD20+ B cells (Fig 3).
The monocyte-derived macrophages show strong CD68 immunoreactivity. No organisms are identified. There are no granulomas. No evidence of tumour is seen.
Luxol Fast Blue (Fig 2) staining shows demyelination within and around areas of inflammation and Bodian staining shows extensive axonal destruction.
Immunostaining for HSV-1, HSV-2, CMV, EBV and SV-40/JC virus are negative. In situ hybridization for EBV DNA is negative.
DIAGNOSIS:
Dural, leptomeningeal and spinal cord biopsies: Necrotizing inflammatory process with overall features most consistent with transverse myelitis. Assay for Aquaporin 4 antibodies might be of assistance in determining aetiology ; granulomas not identified; no evidence of tumour seen.