Table 2.

Characteristics of patients according to type of “essential” or “secondary” mixed cryoglobulinemia (MC). Data are numbers (%) or mean ± SD. Comparison between variables assessed by Fisher exact test. Comparison of means (age at diagnosis and cryoglobulin level) assessed by unpaired t test.

CharacteristicsEssential Type II MC, N = 13Secondary Type II MC N = 20p
Age at diagnosis, yrs62.8 ± 12.257.3 ± 130.84
Female/male6/715/50.14
Severe disease*10 (77)6 (30)0.013
Clinical manifestations
  Raynaud phenomenon5 (38.5)5 (25)0.46
  Purpura12 (92.3)16 (80)0.62
  Skin ulcers5 (38.5)2 (10)0.083
  Arthralgia5 (38.5)11 (55)0.48
  Arthritis1 (7.7)2 (10)0.99
  Renal involvement8 (61.5)4 (20)0.026
  Renal insufficiency4 (30.7)3 (15)0.39
  Peripheral neuropathy11 (84.6)4 (20)0.001
Laboratory features
  Cryoglobulin level, g/l2.8 ± 3.12.5 ± 2.90.77
  Low C4 complement level13 (100)20 (100)NA
  Rheumatoid factor activity13 (100)16 (80)0.13
  Antinuclear antibodies1 (7.7)10 (50)0.022
  Chronic elevated CRP1 (7.7)9 (45)0.049
  • * Clinically overt involvement of at least one extracutaneous organ (see text). CRP: C-reactive protein; NA: not applicable.