A rapid method to estimate Westergren sedimentation rates.
The erythrocyte sedimentation rate (ESR) is a nonspecific but simple and inexpensive test that was introduced into medical practice in 1897. Although it is commonly utilized in the diagnosis and follow-up of various clinical conditions, ESR has several limitations including the required 60 min settling time for the test. Herein we introduce a novel use for a commercially available computerized tube viscometer that allows the accurate prediction of human Westergren ESR rates in as little as 4 min. Owing to an initial pressure gradient, blood moves between two vertical tubes through a horizontal small-bore tube and the top of the red blood cell (RBC) column in each vertical tube is monitored continuously with an accuracy of 0.083 mm. Using data from the final minute of a blood viscosity measurement, a sedimentation index (SI) was calculated and correlated with results from the conventional Westergren ESR test. To date, samples from 119 human subjects have been studied and our results indicate a strong correlation between SI and ESR values (R(2)=0.92). In addition, we found a close association between SI and RBC aggregation indices as determined by an automated RBC aggregometer (R(2)=0.71). Determining SI on human blood is rapid, requires no special training and has minimal biohazard risk, thus allowing physicians to rapidly screen for individuals with elevated ESR and to monitor therapeutic responses.
Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, California 90033, USA.
Tamas
T
Alexy
Eszter
E
Pais
Herbert J
HJ
Meiselman
D001799:Blood Sedimentation; D001809:Blood Viscosity / Q000502:physiology*; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D004912:Erythrocytes / Q000166:cytology* / Q000502:physiology*; D009391:Nephelometry and Turbidimetry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity