The issue of whether fungi causes all CRS gained national attention nearly a decade ago when researchers at the Mayo Clinic announced that fungi were present in nearly all CRS patients, as well as in healthy individuals. After publication of their first data in Mayo Clinic Proceedings (1999;74:877-84), the team demonstrated in follow-up studies that intranasal antifungal treatment (specifically with amphotericin B) improved the objective computed tomography (CT) findings such as inflammatory mucosal thickening, nasal endoscopy stages, and CRS symptoms. After several noncontrolled studies were published, the team further demonstrated positive results with a randomized, double-blind, placebo-controlled trial of 30 CRS patients (J Allergy Clin Immunol 2005;115:125-31).
Studies by researchers in Switzerland and Italy have supported the Mayo findings. Ricchetti et al. (J Laryngol Otol 2002;116:261-3) stated that hyper-reactivity to fungal organisms should be one of the mechanisms underlying the development of nasal polyposis. Additionally, the researchers stated that amphotericin B seems to induce the disappearance of nasal polyps in about 40% of patients.
In 2006, Italian researchers (Corradini et al., J Investig Allergol Clin Immunol 2006;16(3):188-93) said their study indicated that long-term topical treatment with lysine acetylsalicylate and amphotericin B may be clinically effective in the treatment of patients with nasal polyposis associated with fungal infection.