Asthma is a heterogeneous disease. Identification of distinct asthma phenotypes is important to therapeutic decision making. We have previously identified distinct histamine pharmacodynamic (PD) response types (high vs. low) utilizing Histamine Iontophoresis with Laser Doppler monitoring (HILD) in patients with asthma. We aimed to explore the relationship between cytokine profiles and histamine PD response type in children with allergic asthma.
Twenty-three children (mean age 12±3 years) with a diagnosis of allergic asthma previously classified as high or low histamine responders by HILD were enrolled in this pilot study. Cytokine levels were measured in serum quantified by Luminex® for the following cytokines: GMCSF, IFNg, TNFa, IL1b, IL2, IL4, IL5, IL6, IL7, IL8, IL10, IL12 and IL13. All children avoided antihistamines ≥7 days and systemic immunosuppressants > 6 weeks prior to HILD and cytokine measurements. T-test was used to compare mean cytokine values between high and low histamine groups with alpha < 0.05.
We observed that children classified as low histamine PD responders had higher mean cytokine levels for IL5, IL6, IL8 and TNFa vs. high histamine responder PD groups (mean pg/ml 9.2 vs. 1.2, 0.99 vs. 0.16, 9.0 vs. 2.7, 2.3 vs. 0.8 respectively, p values <0.05).
Our findings suggest that there is an association with allergy related cytokine levels and histamine PD response as detected by HILD in children with asthma. This novel biomarker may be useful in asthma phenotyping in children and guiding therapeutic treatment.