Correlation ofimmunoglobulin andCreactive protein levels inankylosing spondylitis and rheumatoid arthritis

SUMMARYSerumCreactive protein (CRP), IgG, andIgAlevels weremeasured in22patients withankylosing spondylitis (AS)andin20patients withrheumatoid arthritis (RA) tostudy the regulation ofthese proteins ininflammatory disease states. InbothRA andASthemeanCRP, IgG,andIgAlevels wereraised abovenormal values. Although IgAandCRPlevels showed a significant positive correlation inRA (r=0-53, p=0-02), there wasnocorrelation between these values inAS(r=0.24, p=0-29). Thedifference incorrelation coefficients between theASand RA groups wassignificant atap=005level. InRA theraised IgAlevels maybeanother manifestation oftheacute phaseresponse, asshownbythegoodcorrelation between IgAand CRPinthat disease. InAS,however, theIgAlevels, although raised, donotcorrelate withCRP levels, suggesting thatthemechanism ofincrease ofIgAinthetwodiseases isdifferent. Gut mediated immunestimulation hasbeenproposed asa causeofraised IgAlevels inAS.