Protein Concentration of Oedema Fluid in Rheumatoid Arthritis : Part I

M.R.C.Rheumatism Research Unit, Canadian RedCrossMemorial Hospital, Taplow Theprotein content ofoedemafluid depends on several factors, including vascular permeability, serumprotein level, lymphatic clearance, venous pressure, andtissue tension. Recently, Parkand Swinburne (1964) reported thatoedemafluid obtained fromthefeetandankles ofpatients with rheumatoid arthritis contained less than1g.percent. protein, andtheysuggested thatitwasatransudate. Thiswasatvariance withtheexperience ofBywaters (1948), whofounda highprotein content inthe neighbourhood oftheswollen andinflamed joints of rheumatoid arthritis; thetissue fluid clotted and contained over2g.percent.protein compared with less than1g.percent. incardiac orrenal oedema. Someofhiscasesshowed aninflammatory oedema forsomemonths before thejoints becameobviously involved. Thepresent investigation was,therefore, undertaken withparticular reference tocasesshowing an active arthritis asjudged bylocal heatandsoft tissue swelling. Inferences about thenatureofthe oedema inactive arthritis maybedrawnmoreeasily inthehandthaninthefoot, because ofthehigher hydrostatic pressure present inthelatter: fluid from bothhands andfeet wastherefore studied. Material andMethods