Eosinophilic Sialodochitis: A Type of Chronic Obstructive Sialadenitis Related to Allergy

Abstract

Objectives To investigate the clinical, laboratory, radiological, histopathological, and immunohistochemical features, and the expression of allergy‐related cytokines in eosinophilic sialodochitis (ES). Methods Thirty‐eight patients diagnosed with chronic obstructive sialadenitis (COS) who had undergone glandular excision or incisional biopsy were enrolled. Seventeen patients with comorbid atopic disease and increased ductal tissue eosinophils comprised the ES group, while 21 patients comprised the COS group. The clinicopathological features and allergy‐related cytokine expression were compared between groups. Results The ES group frequently involved multiple, bilateral major salivary glands, and the number of glands was significantly greater than the COS group (2.8 ± 1.1 vs. 1.2 ± 0.4, P < .001). Serum immunoglobulin (Ig) E was elevated in 91% of patients in ES group (419 ± 357 kU/L) and peripheral blood eosinophil was significantly greater compared with the COS group (7.6% ± 4.6% vs. 2.5% ± 1.4%, P < .001). Histologically, eosinophil infiltration in ES group was observed around the main and interlobular ducts (50 ± 39/high power field [HPF]). Follicular hyperplasia (76%), epithelial mucous metaplasia (82%), and mucus plugs with eosinophils (41%) were observed. IgE‐positive cell count was 20.7 ± 18.3/HPF and tryptase‐positive mast cell count was 23.5 ± 15.1/HPF, which was significantly greater than the respective cell counts in COS group, which mainly infiltrated around the ducts. The levels of interleukin‐4, interleukin‐13, and eotaxin in tissue were significantly greater in ES than the COS group. Conclusions The clinicopathological characteristics of ES are significantly different from COS and ES might have an allergy‐related pathogenesis. Level of Evidence 4 Laryngoscope, 131:E800–E806, 2021

Allergy‐Related Sialodochitis: A Preliminary Cohort Study

“…The present study revealed several clinical features of ARS. The percentage of male patients in the group A was significantly higher compared with group B, that is, relatively more male patients might suffer from ARS, which was similar to the result of Baer et al 7,12 Besides, group A involved more salivary glands compared with group B, which was consistent with the results of Baer et al and Zhu et al 7,12 Moreover, percentage of submandibular gland involvement was higher in group A than that in group B. The underlying mechanisms needed further investigation 15,17–19 …”

“…Most of these patients had atopic diseases during inquiry. The incidence rate of ARS might be underestimated, in view of the increased morbidity of allergic diseases caused by environmental issues in recent years 12,16 …”

“…Among the total 96 patients, only 12 had simultaneous elevation of IgE and PBE. The relatively lower percentage of coexistence of elevated IgE and PBE might be explained by the fact that 1/3 of patients had a history of anti‐allergic medications for the comorbid atopic diseases, which might decrease the count of PBE or serum total IgE 12 . Therefore, we proposed that increase of either PBE or serum IgE as a compromise to define ARS patients.…”

“…Among these criteria, the mandatory features of ES included eosinophil‐rich mucus plugs or histopathologic evidence of periductal eosinophil‐ and lymphocyte‐rich inflammation 7 . Recently, Zhu et al discovered significant expression of allergy‐related cytokines and suggested allergy‐related pathogenesis of ES 12 . All these confirmed the existence of a specific type of sialadenitis related to allergy.…”

“…Based on the principle of minimally invasive surgery and gland preservation, histological samples of ARS were often unsuitable for most cases. Further, a systematic cohort study related to treatment outcomes was lacking 7–12 . The aim of this study was to explore the clinically feasible diagnosis criteria and treatment options of ARS based on a relatively larger sample size.…”