Epidermal growth factor activates a hypoxia-inducible factor 1α-microRNA-21 axis to inhibit aquaporin 4 in chronic rhinosinusitis.

The pathogenesis of chronic rhinosinusitis (CRS) is largely unknown, but accumulating evidence supports the role of the airway epithelium in its pathophysiology. In our study here, we evaluated whether epidermal growth factor (EGF) regulates a hypoxia-inducible factor 1α (HIF-1α)-microRNA-21 (miR-21)-aquaporin 4 (AQP4) axis in nasal epithelial cells from CRS patients. We found that, compared with normal sinus mucosa, EGF, HIF-1α, and miR-21 were upregulated and AQP4 was downregulated in sinus mucosa from patients with CRS and in a CRS mouse model. It was established that EGF upregulated HIF-1α and miR-21 expression, that HIF-1α regulated miR-21 transcription, and that the AQP4 gene was a target of miR-21. Knockdown of EGF and HIF-1α mRNAs and of miR-21, or overexpression of AQP4 mRNA, inhibited proliferation and promoted apoptosis of hypoxia-exposed human nasal epithelial cells, effects that were associated with reduced levels of α-SMA, fibronectin, and vimentin, as well as promoted caspase-3 activity and E-cadherin levels. In the mouse CRS model, EGF elevation increased in vivo production of inflammatory IL-4 and IFN-γ to promote CRS, which was reversed by AQP4 elevation. Collectively, EGF upregulates HIF-1α and miR-21 expression to inhibit AQP4 expression, thereby promoting the proliferation of nasal epithelial cells and the development of CRS.

Transnasal Endoscopy and Combined Approach to Infratemporal Fossa Abscess and Parapharyngeal Abscess.

The infratemporal fossa is a very important anatomical space that is relatively closed with an irregular shape and is adjacent to the parapharyngeal space. Infratemporal fossa abscess is rare clinically. It can occur as a complication of maxillary sinusitis, maxillary sinus fracture, or odontogenic infection. If not handled in time, it may endanger the lives of patients. This paper reports the diagnosis and treatment of infratemporal fossa abscess in 2 diabetic patients. Computed tomography and magnetic resonance imaging are the best methods to diagnose suspected cases of this disease. The key treatment is to combine sensitive antibiotic treatment with endoscopic abscess drainage. Different approaches can be selected according to the range of lesions. If necessary, a combined approach to drain the pus is needed. Early diagnosis, timely initiation of antibiotics, and surgical intervention are essential for curing this disease.

Immunoglobulin G4-related disease presenting with hypertrophy and sclerosis of the inferior turbinate.

Immunoglobulin G4-related disease (IgG4-RD) is a novel clinical disease entity characterized by elevated serum IgG4 concentration and tumefaction or tissue infiltration by IgG4+ plasma cells.1 We report the case of a 56-year-old man who presented with nasal obstruction for 5 years. Rhinoscopy revealed hypertrophy and sclerosis of the inferior turbinate, whereas computed tomography revealed inflammation of the anterior ethmoid sinus and frontal sinuses. An endoscopic inferior turbinectomy was performed, and IgG4-RD was definitively diagnosed based on the histopathological features of the turbinate tissue. Prednisolone was administered postoperatively. IgG4-RD presenting with hypertrophy and sclerosis of the inferior turbinate is rare. Awareness of IgG4-RD originating in the sinonasal cavity is essential to avoid delayed diagnosis.