The new histologic classification of chronic rhinosinusitis.

Two histologic patterns of disease are found in chronic rhinosinusitis. The first is dominated by eosinophilia and polypoid changes. Glandular hyperplasia and hypertrophy characterize the second. We present the evidence supporting the existence of these two patterns of disease and link these histologic patterns to the larger pathophysiologic processes that drive them. This histologic classification should be acknowledged both in the clinical setting and in laboratory research of chronic rhinosinusitis.