Diagnosis:
This is based on clinical features +nerve/muscle biopsy findings of vasculitis +exclusion of systemic causes
Clinical features:
Clinical features: usually subacute, painful, distal, asymmetric,
Findings on investigations:
+Nerve conduction studies +EMG:
- Axonal neuropathy
+CSF analysis: increased protein
+ESR: might be increased
+ANCA negative
Pathology, nerve biopsy:
Sural nerve or superficial peroneal nerve biopsy +/-muscle biopsy (peroneus brevis)
- Arterioles of the epineurium:
- Inflammation: Infiltrate of lymphocytes
- Necrosis of intima and media
- Endothelial cell changes
- Fibrinoid necrosis: a definite sign
- Axons: loss of axons in the periphery of the fascicle i.e. subfascicular ischemic change
- Clusters of demyelination/remyelination is consistent
- Immunohistochemistry: CD3 for T cells
Treatment:
Immunosuppression:
- Prednisolone P.O. +cyclophosphamide I.V.