Zeta sedimentation ratio in rheumatic disease. Comparison of the zeta sedimentation ratio with the Wintrobe and Westergren sedimentation rates.

ABSTRACT

The zeta sedimentation ratios (ZSR) of 104 normal subjects and 106 rheumatology clinic patients were compared with their Westergren and Wintrobe erythrocyte sedimentation rates (ESR). The mean ZSR for normal subjects was 49.42 +/- 3.75%. The rheumatology clinic patients were separated into noninflammatory and inflammatory disease groups. The mean ZSR values for these groups were noninflammatory, 51.60 +/- 5.33%; inflammatory, 59.43 +/- 7.32% (t = 5.5, p less than 0.001). The correlation between ZSR and ESR values was excellent. The ZSR determination has several advantages over the standard ESR in that it can be performed on blood anticoagulated with EDTA and need not be corrected for age, sex or packed cell volume. The ZSR is a rapid, reproducible test correlating well with rheumatic disease activity.