Haematological and serological tests contribute to making the diagnosis and marking progress of the disease and urinalysis is a useful initial screen to evaluate renal involvement (Table 1).
Anaemia | 70-90% |
Leukocytosis | 20-30% |
Microscopic haematuria | 30-50% |
Raised ESR | >90% |
Rheumatoid factor | 50% |
Immune complexes | 65-100% |
Decreased serum complement | 5-40% |