Diagnosis:
Clinical features plus isolation of cryoglobulins
Clinical features:
- Hepatitis
- Purpura (legs), arthralgia, glomerulonephritis
- Raynaud’s phenomenon
- Peripheral neuropathy, precipitated by cold
+serum Cryoglobulins: positive
Type I cryoglobulin: Monoclonal protein without rheumatoid factor activity
- Associated with plasma cell dyscrasia
Type II mixed cryoglobulin MC (formerly essential mixed cryoglobulinemia): Monoclonal protein with rheumatoid factor activity +polyclonal component
- Associated with hepatitis C virus
Type III mixed cryoglobulin MC: Polyclonal protein with rheumatoid factor activity
- Associated with hepatitis C virus
Findings on Investgations:
Serum cryoglobulins: positive
C4: low
NCS/EMG: peripheral neuropathy pattern, mainly sensory
Pathology/nerve biopsy:
Axonal loss
Treatment:
Options:
- Prednisone, chlorambucil, cyclophosphamide, plasma exchange