alcian-blue and Arthritis--Rheumatoid

We used Alcian Blue (AB) and dimethylmethylene blue (DMB) methods to measure glycosaminoglycan (GAG) excretion in the first morning urine specimens of patients with osteoarthritis (OA), ankylosing spondylitis (AS), and rheumatoid arthritis (RA) in different stages of disease. By the AB method, urinary GAG excretion in patients with RA was not different from healthy control subjects. However, the DMB method showed significant differences (in milligrams of GAG per gram of creatinine) for OA (median 25.4, range 14.3-44.0, P less than 0.01, n = 23) and RA patients (median 33.0; range 10.0-147.6; P less than 0.001, n = 63) in comparison with unaffected individuals (median 20.2; range 8.9-41.4, n = 38). We noted a significant difference in urinary GAG excretion between RA and OA patients (P less than 0.01) and between RA and AS (P less than 0.01) patients. The DMB method was further investigated by clinical decision analysis. The DMB method is simple and rapid and may be useful in diagnosing RA by distinguishing between RA and OA or AS.

Topics: Adolescent; Adult; Aged; Alcian Blue; Arthritis, Rheumatoid; Glycosaminoglycans; Humans; Methylene Blue; Middle Aged; Osteoarthritis; Rheumatic Diseases; Spectrophotometry; Spondylitis, Ankylosing

The formation of soluble complexes between alcian blue dye and sulfated glycosaminoglycans provides the basis for the quantitative spectrophotometric estimation of the total concentration of these polysaccharides. Samples containing microgram quantities of sulfated glycosaminoglycan are mixed with a stable dye solution prepared in 15% phosphoric/2% sulfuric acids and absorbance readings at 480 nm are compared to an appropriate standard curve. The method is rapid, convenient, and reproducible. Analyses are performed under conditions in which there is no interference from the non-sulfated glycosaminoglycan hyaluronic acid, or most other anionic macromolecules. In addition, estimations are not effected by small anions or individual monosaccharides. The method has been used for the determination of the purity of commercially available preparations of hyaluronic acid and for the estimation of the sulfated glycosaminoglycan content of various biological fluids including normal human urine and the synovial fluid of individuals with rheumatoid arthritis and osteoarthritis.

Topics: Alcian Blue; Arthritis, Rheumatoid; Chondroitin Sulfates; Glycosaminoglycans; Humans; Osteoarthritis; Spectrophotometry; Synovial Fluid