Predictive Accuracy of Total IgE in Detection of Inhalant Allergens Sensitization

Background: The role of total IgE (TIGE) in detecting inhalant allergens (IA) sensitization in asthmatics is controversial and frequently underestimated. Objective: To test the relationship between TIGE and IA sensitization in asthmatics. Methods: One year duration cross-sectional study commencing from January in 2014. 118 asthmatics with mean age of 30±15 years collected from King Abdulaziz University Hospital (KAUH). TIGE and skin prick test (SPT) was done. Data were statistically analyzed by statistical package for the social sciences program (SPSS). Two by two tables was done to correlate TIGE and IAs sensitization. Sensitivity, specificity, positive predictive values (+PV) and negative predictive values (– PV) were calculated. Results: SPSS two by two tables was used to correlate TIGE with IA sensitization by sensitivity, specificity and predictive values. TIGE versus mites showed high sensitivity: Dermatophagoides pteronyssinus (DP) 80.3, Dermatophagoides farina (DF) 83.7 and low (specificity, +PV and –PV). TIGE versus mold showed high –PV to (Aspergillus 82.1, Cladosporium 78.5) and low (sensitivity, specificity and +PV). TIGE versus German cockroach showed high sensitivity 90 and high –PV 92.8, however both specificity and +PV were low. All the values were statistically significant with P values below 0.05. Conclusion: Raised TIGE in asthmatics is of value in predicting dust mites and cockroach sensitization and exclusion of mold sensitization. High TIGE in asthmatics almost certainly mean the presence of mite sensitization. Conversely, normal TIGE in asthmatics can exclude mold sensitization. TIGE have both roles with German cockroach (highly sensitive, high –PV).