Prediction Method for Selective Application of a Rapid Tetanus Antibody Test In Patients who Visit the Emergency Department with a Wound

Lee, Se Uk; Shin, Jong Hwan; Song, Kyoung Jun; Kim, Hahn Bom; Hong, Ki Joeng

Abstract

PURPOSE
Tetanus vaccine or immunoglobulin is given routinely to patients with wounds according to immunization history. Our aim is to identify prediction factors that affect tetanus antibody titer, which lead to proper application of an antibody screening test according to the factors.
METHODS
Subjects who visited the emergency department after injury from October 2008 to February 2010 were enrolled. The Tetanus Immunoglobulin G ELISA (Enzyme-linked immunosorbent assay) method was used for analysis of serum samples. Using multivariate analysis, we identified statistically significant variables affecting the tetanus antibody titer. And we developed the Boramae Tetanus Score as a screening model.
RESULTS
A total of 1218 samples were analyzed. Significant factors affecting tetanus antibody titer were as follows: Age in the twenties, thirties, and fifties, male sex, and experience of military service. We assigned proper scores to each variable using the beta-coefficients. The area under the Receiver Operating Characteristic (ROC) curve of the scoring system was 0.807. Patients were categorized as high risk and low risk groups; 18.0% of the high risk group and 67.7% of the low risk group had serum tetanus antibody titer higher than safe antibody level (0.1 IU/mL).
CONCLUSION
The antibody titer of the high risk group was low enough for performance of routine immunization. "In order to prevent unnecessary immunization, patients in the low risk group should undergo screening using proper tools".