Case 123. HTLV-1-associated myelopathy (HAM) (54 y-o F)
         
   
Slowly progressive spastic paralysis in an HTVL-1 carrier in Kyushu
   
         
   
Key words : HTLV-1-associated myelopathy, demyelination
   
     
 
     
In HAM, the main lesion is located in the white matter at the thoracic spinal cord level. Demyelination of the lateral column is evident (LFB-HE, low power).   In the lateral column, perivascular infiltation of small lymphocytes and vacuolar change of the neuropil are observed (LFB-HE).
     
 
     
The small lymphocytes around vessels express CD45-RO, a T-cell phenotype (immunostaining). CD8 cells predominate. No atypical lymphocytes are seen in tissues, nor is clinical manifestation of ATL.   In this case, lymphocytic infiltration is also focally noted in the root of the spinal nerve (LFB-HE).
     
 
     
Reference case 123A
Another case (38 y-o F) of HAM in Kyushu, manifesting spastic paralysis. The lateral columns show severe demyelination and axonal loss with gliosis and lymphocytic infiltration (LFB-PAS). Myelinated fibers are extensively lost. Neurons are preserved.
  Reference case 123A
Another case (38 y-o F) of HAM in Kyushu, manifesting spastic paralysis. Accumulation of foam cells and lymphocytes is observed around small vessels in the lateral column (HE).