The MUC5AC area was decreased significantly in nasal epithelium from patients with CRSr (425.6 μm2, 0–2162.0 μm2, P < 0.001) and was increased significantly in nasal epithelium from patients with CRSsNP (1821.0 μm2, 40.58–3632.0 μm2, P < 0.001) compared to controls (1216.0 μm2, 655.9–1800.0 μm2) (Fig. 1c). The gene discussed is MUC5AC; the disease is chronic rhinosinusitis without nasal polyps.