Two Type 2 Inflammation Markers Elevated in Patients With Prurigo Nodularis

Patients with prurigo nodularis had elevated blood levels of the type 2 inflammatory biomarkers interleukin (IL)-13 and periostin compared with control subjects, according to study findings published in Frontiers in Medicine.

“IL-13 is also increased in atopic dermatitis and is a potent enhancer of neuronal responses of pruritus and neurogenic inflammation,” wrote a researcher team from the Johns Hopkins University School of Medicine Department of Dermatology in Baltimore, Maryland, and Eli Lilly and Company in Indianapolis, Indiana. “Periostin is an extracellular matrix protein located in the dermis that is involved in type 2 inflammatory responses and is correlated with progressive sclerosis in systemic sclerosis.”

Researchers tested circulating plasma of 29 patients with uncontrolled prurigo nodularis and 18 control patients without pruritus from a Johns Hopkins outpatient dermatology clinic. Participants had similar age, sex, and race distributions, and their plasma was assayed specifically for IL-4, IL-5, IL-13, immunoglobulin E (IgE), and periostin.

Study results showed significantly elevated circulating plasma IL-13 (0.13 vs 0.006 pg/mL) and periostin (80.3 vs 60.2 ng/mL) in participants with prurigo nodularis compared with control participants. While the difference in IgE approached significance, IL-4 and IL-5 were not significantly elevated in participants with prurigo nodularis.

Clustering of all study participants revealed two clusters, researchers reported. Cluster 1 consisted of 18 patients with prurigo nodularis and 18 controls, and Cluster 2 consisted of 11 patients with prurigo nodularis. Compared with Cluster 1, Cluster 2 had higher levels of IL-13 and IL-5, according to the study.

“The identification of endotypes with varying degrees of inflammatory axis signaling may help explain varying differences in phenotypic presentation observed between patients,” researchers wrote. “Given the diversity of this disease, further biomarker studies may help elucidate future precision medicine approaches in the management of prurigo nodularis.”

Reference:
Parthasarathy V, Cravero K, Deng J, et al. Circulating plasma IL-13 and periostin are dysregulated type 2 inflammatory biomarkers in prurigo nodularis: a cluster analysis. Front Med (Lausanne). Published online December 6, 2022. doi:10.3389/fmed.2022.1011142