59 yo lady complaining of weakness of the left lower limb, was admitted 2 months ago for evaluation. Physical examination reveals dysesthesia of both limbs, no biological significant finding, and MRI discloses degenerative changes of lumbar intervertebral discs, but with no root compression.

Persistance of the symptoms, with increase in the muscle weakness (foot drop), with the detection of a microscopic hematuria,led to a muscle, skin and a bladder biopsy.

Muscle biopsy

Low power features, slight changes some vascular lumens, mainly with preserved muscle fibers.

Low power at the edge of one section.

Deeper recuts, reveal the presence of a more massive intravascular proliferation

Giemsa stain on the previous field.

Immunohistochemistry