Blood eosinophils may predict radiographic sinus opacification in patients with chronic rhinitis

Immunopathologic Role of Eosinophils in Eosinophilic Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a diverse chronic inflammatory disease of the sinonasal mucosa. CRS manifests itself in a variety of clinical and immunologic patterns. The histological hallmark of eosinophilic CRS (ECRS) is eosinophil infiltration. ECRS is associated with severe disease severity, increased comorbidity, and a higher recurrence rate, as well as thick mucus production. Eosinophils play an important role in these ECRS clinical characteristics. Eosinophils are multipotential effector cells that contribute to host defense against nonphagocytable pathogens, as well as allergic and nonallergic inflammatory diseases. Eosinophils interact with Staphylococcus aureus, Staphylococcal enterotoxin B, and fungi, all of which were found in the tissue of CRS patients. These interactions activate Th2 immune responses in the sinonasal mucosa and exacerbate local inflammation. Activated eosinophils were discovered not only in the tissue but also in the sinonasal cavity secretion. Eosinophil extracellular traps (EETs) are extracellular microbes trapping and killing structures found in the secretions of CRS patients with intact granule protein and filamentous chromatic structures. At the same time, EET has a negative effect by causing an epithelial barrier defect. Eosinophils also influence the local tissue microenvironment by exchanging signals with other immune cells and structural cells. As a result, eosinophils are multifaceted leukocytes that contribute to various physiologic and pathologic processes of the upper respiratory mucosal immune system. The goal of this review is to summarize recent research on the immunopathologic properties and immunologic role of eosinophils in CRS.

Peripheral blood eosinophil and classification of residual hematoma help predict the recurrence of chronic subdural hematoma after initial surgery

Chronic subdural hematoma (CSDH) is a common type of intracranial hemorrhage in neurosurgical practice, whose incidence has increased markedly in recent years. However, CSDH still troubles clinicians with a high postoperative recurrence rate. The presence of eosinophils has been confirmed in some CSDH surgical specimens. Furthermore, postoperative residual hematoma has not been classified, and its association with the recurrence of CSDH remains unknown. The present study aimed to test the hypothesis that the peripheral blood eosinophils and the classification of postoperative residual hematoma are significant for the prediction of CSDH recurrence after burr-hole surgery. A retrospective review of 258 CSDH patients who received burr-hole surgery was performed. A complete blood picture with differential count was taken before surgery. Clinical, laboratory, and radiographic factors predicting CSDH recurrence were identified in univariable and multivariable analyses. Univariable analysis showed that the percentage of eosinophils, peripheral blood eosinophil count <0.15 × 10⁹/L, gradation and separated types, postoperative volume of the residual cavity ≥70 ml, residual air volume ≥28 ml, residual hematoma volume ≥55 ml, residual hematoma width ≥1.4 cm, postoperative midline shift ≥5.6 mm, postoperative brain re-expansion rate <41%, postoperative low-density type, and postoperative high-density type correlated with the recurrence of CSDH. Multivariable analysis, however, showed that peripheral blood eosinophil count <0.15 × 10⁹/L, gradation and separated types, preoperative midline shift ≥9.5 mm, postoperative brain re-expansion rate <41%, postoperative low-density type, and postoperative high-density type are independent predictors for the recurrence of CSDH. We expect that peripheral blood eosinophils and the classification of postoperative residual hematoma may facilitate our understanding of the recurrence of CSDH after initial surgery.

Effect of sinus opacification on the severity of obstructive sleep apnea

PURPOSE

The association between rhinosinusitis and obstructive sleep apnea (OSA) remains unclear. Here, we aimed to elucidate the association between sinus opacification and OSA severity.

METHODS

Patients with snoring problems who visited our clinic from April 2018 to December 2020 were retrospectively enrolled. Among these patients, we included those who underwent a physical examination, overnight polysomnography, and osteomeatal-unit computed tomography. We evaluated the association between apnea-hypopnea index (AHI) and Lund-Mackay score (LMS). LMS ≥ 5 was considered indicative of sinus opacification.

RESULTS

Among the 122 patients included in the study, LMS exhibited an increasing trend based on OSA severity. The LMS in the moderate OSA group was significantly higher than that in the no OSA group (P = 0.002), and the LMS in the severe OSA group was significantly higher than that in the no OSA (P < 0.001) and mild OSA (P = 0.006) groups. A correlation analysis revealed that AHI was significantly associated with body mass index (BMI) (r = 0.367, P < 0.001) and LMS (r = 0.255, P = 0.005). A multivariate analysis revealed that sinus opacification was associated with moderate and severe OSA [Adjusted odds ratio = 11.986 (P = 0.005) and 3.756 (P = 0.044), respectively] after adjusting for age, sex, BMI, smoking, hypertension, atopy, tonsil size, and palatal position. The effect of sinus opacification on OSA severity was comparable to that of overweight.

CONCLUSION

Sinus opacification may increase OSA severity since moderate and severe OSA is independently associated with it.

Inflammatory features and predictors for postsurgical outcomes in patients with nasal polyps stratified by local and systemic eosinophilia

BACKGROUND

In this study we aimed to identify inflammatory patterns and predictors associated with clinical outcomes in chronic rhinosinusitis with nasal polyps (CRSwNP) patients with different blood and tissue eosinophilia.

METHODS

A total of 535 CRSwNP patients were enrolled, and the expression of 35 biomarkers, together with eosinophil and neutrophil counts in nasal polyps, were analyzed in a subset of 249 patients. Patients were stratified on the basis of blood (≥0.5 × 10⁹ /L) and tissue (>10%) eosinophilia. Logistic regression models were applied to identify predictors of uncontrolled disease at least 1 year after surgery. Uncontrolled disease was defined according to the European Position Paper on Rhinosinusitis and Nasal Polyps 2020.

RESULTS

Among 535 patients, 38.5% showed inconsistent blood and tissue eosinophilia. In 249 CRSwNP patients, subjects with concomitant blood and tissue eosinophilia (group 1) showed marked mucosal type 2 inflammation, characterized by high levels of interleukin (IL)-5, IL-13, and eotaxin-1, whereas subjects with normal blood and tissue eosinophil levels (group 4) demonstrated significant local neutrophilic inflammation with high expression of granulocyte colony-stimulating factor and subjects with selective tissue eosinophilia (group 2) showed intermediate and mixed eosinophilic and neutrophilic inflammation. Subjects with isolated blood eosinophilia (group 3) showed low expression of vascular endothelial growth factor and IL-10. Asthma, prior sinus surgery, and blood eosinophilia were the top 3 predictors for postsurgical uncontrolled disease. For subgroup analysis, sex in group 1, asthma in group 2, tissue IL-10 and immunoglobulin E in group 3, and prior sinus surgery in group 4 were the strongest predictors of uncontrolled disease, respectively.

CONCLUSION

Different blood and tissue eosinophilia revealed distinct tissue inflammatory patterns in CRSwNP patients.