QUANTITATIVE CAPILLARY REVERSED PASSIVE LATEX AGGLUTINATION-TEST FOR C-REACTIVE PROTEIN (CRP) IN THE DOG

A capillary reversed passive latex agglutination test (capillary RPLA) was developed which allows quantification of serum C-reactive protein (CRP) within approximately 15 min. The logarithmic regression line (c alibration curve) obtained after measuring each CRP concentration thre e times in twofold dilutions of a standard canine serum containing 222 mu g/ml of CRP was y=6.394+0.030x (r=0.995). Capillary RPLA permitted quantification of CRP in the range 6.9-222 mu g/ml. The coefficients of variation ranged from 10.28% to 12.40%. The recovery rates (percent age recovery) of CRP by capillary RPLA were within the range 87% to 10 6%. On measuring the CRP concentrations in sera from 78 dogs by capill ary RPLA, single radial immunodiffusion (SRID) and enzyme-linked immun osorbent assay (ELISA), close correlations were demonstrated between S RID and capillary RPLA Oi 7.250+1.109x, r=0.978), between SRID and ELI SA (y=3.042+1.059x, r=0.967), and between capillary RPLA and ELISA (y= 1.778+0.929x, r=0.962). Capillary RPLA may be considered useful as a r outine biochemical technique for measurement of serum CRP concentratio n in the dog.