The authors refer to 21 adult patients at the age of 22 to 87 years,whohave suffered from a chronic form of follicular conjunctivitis, found to be caused by Chlamydia pneumoniae as the etiological agent. The observation wasmade in the period from July 1999 to December 2002. Chl. pneumoniae was detected by a direct demonstration of the conjunctiva smears and by means of serological examination. The print preparations on glass were examined by the method of indirect immunofluorescence by means of specific monoclonal antibodies (Medac, Germany). The serological examination included detection of genus-specific IgG, IgA, IgM antibodies, respectively (Medac, Germany) and species-specific anti-Ch. pneumoniae IgG, IgA abd IgM antibodies, respectively (FOCUS Technologies, U.S.A.). The clinical picture included various long-termsubjective complaints (within the range of several months to ten years), particularly a pathological secretion or increased lacrimation, cutting, burning or feeling of a foreign body in the eye. The objective examination revealed chronic changes characterized by a mild edema of bulbar conjunctiva with increased meandering in vessels of irregular caliber and edema in the lower transition plica with follicular structure crossing into the tarsal conjunctiva. In the fornix there was an apparent sticking aqueous or mucinous secretion. The therapy was indicated by the positivesmears alone in four patients or positive IgA and/or IgM of genus- or species-specific antibodies in 12 patients. The therapy in the remaining five patients was recommended by the combination of suspectpositive smears in combination with positive genus- or species specific antibody reaction. The therapy made use of systemic administration of a macrolide antibiotic, azithromycin, for the period of 12 to 14 days in a single course of treatment. The pretreatment was always followed by control smears after two weeks and by serological examinations after three and six months. The serological findings remained virtually unchanged during that period of time in all patients under observation. In two of them only the species-specific antibodies anti-Ch. pneumoniae IgA antibodies disappeared six months after the therapy. The clinical findings disappeared slowly, particularly the follicular changes occurred aftermore than six months after the therapy ended. The subjective complaints, accompanied by a transient hyperemia of conjunctives in particular, remained after the therapy in nine patients older than 45 years, who were foundto suffer fromkeratoconjnunctivitis sicca.Theocular symptomatology was not accompanied by symptoms of autoimmune disease. The general treatment by antibiotics and the results supportive treatment succeeded in 67% of patients who were completely free of subjective complaints and the pathological process in conjunctives was inhibited.

        Key words: Chlamydia pneumoniae, Follicular conjunctivitis, Keratoconjunctivitis sicca, Mecrolide antibiotics