Some chronic rhinosinusitis with nasal polyps patients undergo revision surgery at some point following initial functional endoscopic sinus surgery. This review aimed to identify the predictive factors for recurrence of nasal polyps requiring oral corticosteroids or revision surgery in chronic rhinosinusitis with nasal polyps following functional endoscopic sinus surgery.

A retrospective analysis of 221 patients who underwent functional endoscopic sinus surgery for chronic rhinosinusitis with nasal polyps in a tertiary rhinology centre, between January 2015 and December 2018, was undertaken.

Forty-four (21.6 per cent) patients underwent medical polypectomy, 19 (9 per cent) underwent revision surgery and 51 (24.3 per cent) underwent combined polypectomy during the mean follow-up time of 5.3 years. Patients aged less than 55 years of age, with a history of previous functional endoscopic sinus surgery, peripheral blood eosinophil counts of 300 cells/μl or higher, a Lund–Mackay score of more than 17 and concomitant aspirin-exacerbated respiratory disease had significantly increased odds for medical polypectomy, revision surgery and combined polypectomy.

Knowing these predictive factors, clinicians can better identify patients with an increased likelihood of severe polyp recurrence and therefore arrange closer follow-up to optimise therapy.

This study aimed to explore the utility of the eosinophil percentage in peripheral blood for guiding post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps.

Forty-four patients with chronic rhinosinusitis with nasal polyps underwent functional endoscopic sinus surgery and were randomly divided into two groups. Patients in the standard treatment group used oral and nasal spray glucocorticoids. In the biomarker treatment group, patients with peripheral blood eosinophil percentage values less than 3.05 per cent did not receive glucocorticoid treatment, whereas patients with values 3.05 per cent or above were part of the standard treatment group. Visual Analogue Scale, Sino-Nasal Outcome Test-22 scores, endoscopic Lund–Kennedy scores, eosinophils, interleukin-5 and eosinophil cationic protein in peripheral blood, and nasal secretions were measured.

After functional endoscopic sinus surgery, the Visual Analogue Scale, Sino-Nasal Outcome Test-22 and Lund–Kennedy scores were significantly reduced in both groups; there were no significant differences in those indicators between the groups during the three follow-up visits.

Peripheral blood eosinophil percentage offers a potential biomarker to guide post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps.

Severe acute respiratory syndrome coronavirus-2 uses angiotensin-converting enzyme-2 as a primary receptor for invasion. This study investigated angiotensin-converting enzyme-2 expression in the sinonasal mucosa of patients with chronic rhinosinusitis, as this could be linked to a susceptibility to severe acute respiratory syndrome coronavirus-2 infection.

Ethmoid sinus specimens were obtained from 27 patients with eosinophilic chronic rhinosinusitis, 18 with non-eosinophilic chronic rhinosinusitis and 18 controls. The angiotensin-converting enzyme-2 and other inflammatory cytokine and chemokine messenger RNA levels were assessed by quantitative reverse transcription polymerase chain reaction. Angiotensin-converting enzyme-2 positive cells were examined immunohistologically.

The eosinophilic chronic rhinosinusitis patients showed a significant decrease in angiotensin-converting enzyme-2 messenger RNA expression. In the chronic rhinosinusitis patients, angiotensin-converting enzyme-2 messenger RNA levels were positively correlated with tumour necrosis factor-α and interleukin-1β (r = 0.4971 and r = 0.3082, respectively), and negatively correlated with eotaxin-3 (r = −0.2938). Angiotensin-converting enzyme-2 immunoreactivity was mainly localised in the ciliated epithelial cells.

Eosinophilic chronic rhinosinusitis patients with type 2 inflammation showed decreased angiotensin-converting enzyme-2 expression in their sinus mucosa. Angiotensin-converting enzyme-2 regulation was positively related to pro-inflammatory cytokines, especially tumour necrosis factor-α production, in chronic rhinosinusitis patients.

To investigate lung function in Chinese patients suffering from chronic rhinosinusitis with nasal polyps and examine its association with histopathological features.

The lung function of 99 patients with nasal polyps was measured. Haematoxylin and eosin and immunohistochemistry staining were performed to evaluate any inflammatory cells and epithelial tissue remodelling.

Predicted maximal expiratory flow rate at 25 per cent vital capacity was reduced (p < 0.05) in epithelial hyperplasia, and predicted maximal expiratory flow rate at 50 per cent vital capacity was reduced (p < 0.05) in goblet cell hyperplasia. Both peripheral blood eosinophilia and tissue eosinophilia nasal polyps manifested significantly reduced: forced expiratory volume in 1 second/forced vital capacity ratio, predicted maximal expiratory flow rate at 25, 50 and 75 per cent of vital capacity, and predicted maximal mid-expiratory flow. Peripheral blood eosinophils were negatively correlated with predicted maximal expiratory flow rate at 25 and 50 per cent of vital capacity, and predicted maximal mid-expiratory flow. Eosinophils in tissue were negatively correlated with all lung function parameters investigated except predicted forced vital capacity.

Clinicians should be aware of lung function decline in nasal polyps patients, especially in those with tissue eosinophilia.

Although human paranasal sinuses are critical organs for nitric oxide production, little information is available regarding the role of arginase in alterations of arginine metabolism and nasal nitric oxide levels that may be informative for classifying chronic rhinosinusitis subtypes.

The expression and localisation of arginase and nitric oxide synthase isoforms in paranasal sinus mucosa were examined, and the fractional exhaled nitric oxide was measured in chronic rhinosinusitis without nasal polyps (n=18) and chronic rhinosinusitis with nasal polyps (n = 27) patients.

Increased arginase-2 activities in chronic rhinosinusitis without nasal polyps patients were associated with significantly lower levels of nasal fractional exhaled nitric oxide. Chronic rhinosinusitis with nasal polyps patients showed significant NOS2 messenger RNA upregulation with concomitant higher levels of oral and nasal fractional exhaled nitric oxide.

These results indicate that fractional exhaled nitric oxide is a valid marker for differentiating chronic rhinosinusitis phenotypes based on a delicate balance between arginase and nitric oxide synthase activities in nitric oxide production.

Nasal polyposis is one of the most common inflammatory pathologies of the nasal cavity. Eosinophilic inflammation plays an important role in the pathogenesis. This study aimed to investigate soluble tumour necrosis factor related apoptosis-inducing ligand levels and eosinophil count in nasal polyposis patients.

The study was performed on 24 adult nasal polyposis patients and 24 age-matched healthy individuals. The patients had not received any medical or surgical treatment. Pre-operative computed tomography scans were assessed using the Lund–MacKay grading system, and soluble tumour necrosis factor related apoptosis-inducing ligand levels were measured with a sandwich enzyme-linked immunosorbent assay.

Compared with controls, eosinophil levels in nasal polyposis patients were increased (p = 0.024), but there was no significant difference in soluble tumour necrosis factor related apoptosis-inducing ligand levels (p = 0.529). The Lund–Mackay mean grading was 12.43 ± 6.9. There was no correlation between soluble tumour necrosis factor related apoptosis-inducing ligand level and Lund–Mackay grading and eosinophil count.

There was no relationship between soluble tumour necrosis factor related apoptosis-inducing ligand level and blood eosinophil or clinical markers; however, soluble tumour necrosis factor related apoptosis-inducing ligand level remains of interest for future studies.

Eosinophilic angiocentric fibrosis is a rare benign disorder of the upper respiratory tract. It is slow growing and progressive, with characteristic histological appearances.

We report the largest single-institution case series of sinonasal eosinophilic angiocentric fibrosis to date, comprising nine patients. The current literature is reviewed, showing emerging evidence that this condition may belong to the immunoglobulin G4-related disease spectrum.

The series comprised five female and four male patients, with a mean age at presentation of 53 years. All were treated surgically. Six patients had no signs of recurrent disease after an average of 8.5 years. One patient went on to develop granulomatosis with polyangiitis (Wegener's granulomatosis), which required immunosuppressive therapy.

The first-line management of this rare condition is complete surgical excision. Chronic granulomatous conditions, including granulomatosis with polyangiitis, should be excluded before a diagnosis is made, and patients should be carefully followed.

Eosinophils may affect each stage of tumour development. Many studies have suggested that tumour-associated tissue eosinophilia (TATE) is associated with favourable prognosis in some malignant tumours. However, only a few studies exist on TATE in central nervous system (CNS) tumours. Our recent study exhibited eosinophils in atypical teratoid/rhabdoid tumours (AT/RTs), pediatric malignant CNS tumours with divergent differentiation. This study examines eosinophils in pilocytic astrocytomas (PAs).

The study included 44 consecutive cases of patients with PAs and no concurrent CNS inflammatory disease.

We found eosinophils in 19 (43%) of 44 PAs (patient age range, 0.5-72 years). Eosinophils were intratumoural and clearly distinguishable. The density of eosinophils was rare to focally scattered. PAs containing eosinophils were located throughout the CNS. Furthermore, eosinophilic infiltration was identified in 18 (62%) of 29 pediatric (age range, 0.5-18 years) PAs but only 1 (7%) of 15 (p<0.001, significantly less) adult (age range, 20-72 years) PAs. Eosinophilic infiltration showed no significant differences between PAs with and without MRI cystic formation, surgical procedures, or PAs with and without leptomeningeal infiltration. In comparison, eosinophils were absent in 10 pediatric (age range, 0.5-15 years) ependymomas (or anaplastic ependymomas).

These results suggest that eosinophils are common in pediatric PAs but rare in adult PAs. This difference is probably related to the developing immune system and different tumour-specific antigens in children. TATE may play a functional role in the development of pediatric PAs, as well as some other pediatric CNS tumours such as AT/RTs.

Immunoglobulin G4 related disease is a rare condition. Cases involving the sinonasal region are exceptionally uncommon. This paper describes a case of immunoglobulin G4 related disease isolated solely to the nasal cavity.

Case report and literature review.

A 34-year-old man presented with painless, progressive bilateral nasal obstruction. Clinical examination and imaging findings demonstrated bilateral submucosal swelling of the anterior septum and right external nasal wall. Biopsy revealed immunoglobulin G4 related disease. The patient responded to oral corticosteroids initially, followed by long-term methotrexate.

To the best of our knowledge, this case represents the first report in the literature of immunoglobulin G4 related disease isolated solely to the nasal cavity.

We aimed to evaluate the relationship between swimming pool pollutants and allergic rhinitis in swimming pool workers.

Twenty-seven indoor pool workers (group 1) and 49 control subjects (group 2) were enrolled in the study. A skin prick test was performed and a nasal smear was obtained from each subject to evaluate rhinitis.

When the groups were compared in terms of epithelial cells, group 1 had significantly more epithelial cells than group 2. When the groups were compared with regard to eosinophils, group 1 had significantly more eosinophils than group 2. The skin prick test results for both groups were not significantly different.

Indoor pool workers showed severe symptoms of rhinitis and eosinophilic nasal cytology, likely due to chlorine. Nasal cytology is an easy-to-administer diagnostic test and can be used to follow up rhinitis in indoor pool workers, along with nasal endoscopy, a detailed clinical history and a skin prick test.

Little is known about the effects of macrolides on the cytokines and chemokines that modulate the function of eosinophils in nasal polyposis.

Twenty-two non-allergic and 18 allergic patients with nasal polyps were administered clarithromycin 500 mg/day (single oral dose) for eight weeks. We measured the nasal secretion levels of the T helper 2 (also known as Th2) cytokines interleukin 4, 5 and 6, the ‘regulated on activation, normal T cell expressed and secreted’ (also known as RANTES) chemokine, and the eosinophilic cationic protein, before and after treatment.

After clarithromycin treatment, we found reduced levels of the ‘regulated on activation, normal T cell expressed and secreted’ chemokine in samples from both non-allergic and allergic patients (p < 0.05). Clarithromycin treatment decreased the levels of eosinophilic cationic protein only in non-allergic patients (p < 0.05), and decreased the level of interleukin 6 only in allergic patients (p < 0.05). Decreased levels of the ‘regulated on activation, normal T cell expressed and secreted’ chemokine were associated with a reduction in polyp size both in non-allergic and allergic patients.

Clarithromycin has a strong anti-inflammatory effect in nasal polyposis, but has different immunomodulatory effects in allergic and non-allergic nasal polyposis patients.