Papillary Versus Follicular Conjunctivitis
Most cases of conjunctivitis are diagnosed as either papillary or follicular according to the macroscopic and microscopic appearances of the conjunctiva (Fig 5-5). Neither type is pathognomonic. Clinically, papillary conjunctivitis shows a cobblestone arrangement of small nodules with central vascular cores (Fig 5-6A). Histologically, papillae appear as closely packed, flat-topped epithelial projections, with inflammatory cells in the stroma surrounding a central vascular channel (Fig 5-6B). Follicular conjunctivitis is characterized clinically by the presence of follicles (Fig 5-7A): small, pink, dome-shaped nodules with overlying vessels but without a prominent central vessel. Histologically, a follicle appears as a dense oval aggregate of lymphocytes in the superficial stroma. The lymphocytes are occasionally arranged into reactive follicles with germinal centers composed of large proliferating B cells, surrounded by a mantle of smaller, more differentiated B cells (Fig 5-7B).
Excerpted from BCSC 2020-2021 series: Section 4 - Ophthalmic Pathology and Intraocular Tumors. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.