Immunomodulatory and Clinical Effects of Long-Term Low-Dose Macrolide Treatment of Chronic Rhinosinusitis with Nasal Polyposis

Immunomodulatory treatment of chronic rhinosinusitis with nasal polyposis (CRSwNP) by macrolide antibiotics represents a challenging alternative to conventional therapy and surgery, still being at the very beginning. Immune and inflammatory processes in nasal and paranasal sinus mucosa, crucial in the etiopathogenesis of nasal polyps (NPs) are reflected in levels of various local mediators, found both in mucosa and nasal fluid. In this prospective study, we assessed the immunomodulatory and clinical effects of longterm low-dose oral macrolide treatment in the management of CRSwNP. Twenty-two (n = 22) nonasthmatic, nonallergic patients with CRSwNP were administered clarithromycin (CAM) 500 mg/day single oral dose for eight weeks. We measured the levels of proinflammatory cytokines TNF-α, TNF-β, and IL-1β, Th1 cytokines IL-2, IL-12, and IFN-γ, Th2 cytokines IL-4, IL-5, IL-6, and IL-10, and chemokine IL-8 in the nasal fluid samples, before and after treatment, using a flow cytometric method. We also scored each of the 22 patients before and after therapy according to Tsicopoulos' global nasal symptom score and Malm's endoscopic score. Following treatment, we found significantly reduced levels of IL-8 (p