Is the skin sensitivity test required for administering equine rabies immunoglobulin?

This research explores the necessity of a skin sensitivity test prior to administering equine rabies immunoglobulin (ERIG) for rabies exposure. Results show that the test may not be required as it poorly predicts adverse reactions to ERIG, in line with World Health Organization (WHO) recommendations.

Objective of the Study

• The purpose of this study is to examine the importance of a skin sensitivity test that’s traditionally executed before administering equine rabies immunoglobulin (ERIG) to patients severely exposed to rabies.
• The research aim was prompted by the conflicting views between product inserts that recommend a skin sensitivity test and the World Health Organization (WHO) guidelines, which argue that the test is unnecessary as it doesn’t accurately predict reactions.

Methods

• Data for the study was collected from the Antirabies Clinic of the Kempegowda Institute of Medical Sciences Hospital in Bengaluru, India, over a 26-month period between June 2008 to July 2010.
• The skin sensitivity test’s validity was evaluated based on its sensitivity, specificity, predictability, and the rate of false positives and negatives.

Results

• Out of all studied subjects, 1.5% reported adverse events (a total of 51), representing 2.6% of the research population.
• Most of the observed adverse events were mild to moderate and subsided without medication.
• No serious adverse events were noted.
• The skin sensitivity test showed a sensitivity of 41.9% and specificity of 73.9% in predicting adverse events.

Conclusion

• The study concludes that conducting a skin sensitivity test before administering ERIG may not be necessary, aligning the research findings with the WHO’s recommendation.
• The test demonstrated a suboptimal predictive power for possible adverse reactions, suggesting its use could be reconsidered in the future clinical practices involving ERIG use.