Monitoring the acute phase response to vaso-occlusive crisis in sickle cell disease.

AIMS To identify suitable acute phase proteins as objective markers of tissue ischaemia during painful vaso-occlusive crises in sickle cell disease. METHODS The prodromal and established phases of 14 vaso-occlusive crises were studied longitudinally in 10 patients with sickle cell anaemia. Automated solid phase enzyme immunoassays were used to measure the fast responding acute phase proteins C-reactive protein and serum amyloid A protein. Slower responding glycoproteins (fibrinogen, orosomucoid, sialic acid and concanavalin-A binding) were measured in parallel. RESULTS C-reactive protein and serum amyloid A protein increased early in crisis, sometimes within the early (prodromal) phase. Crises that resolved within 24 hours in hospital showed a minor and transient rise compared with crises that required treatment for four days or more. In eight crises treated by patients at home the acute phase response ranged from minor to a level consistent with extensive tissue ischaemia. CONCLUSIONS Sensitive enzyme immunoassays for C-reactive protein and serum amyloid A protein are of potential value for monitoring the onset of tissue ischaemia in sickle cell crisis and for confirming subsequent resolution.