Helicobacter pylori, one of the world's most prevalent pathogens, is a spiral-shaped, catalase-positive, Gram-negative rod with 4-6 sheathed flagella attached to one pole which allow for motility. The prevalence of H. pylori infection in humans is high; 50% of those over the age of 60 are infected. H. pylori infection causes chronic gastric inflammation, ulcer disease and gastric carcinoma. Further, chronic antigenic stimulation driven by H. pylori infection has been linked to the development of gastric mucosa associated lymphoid tissue (MALT) lymphoma. Infection with H. pylori induces a vigorous immune response resulting in the presence of local and systemic antibodies. H. pylori-specific immunoglobulin G antibodies present in serum, plasma, whole blood, saliva, gastric juice and urine have each been used to successfully detect the presence of infection in adults. The sensitivity and specificity of serological tests range from 80% to 95% depending upon the assay used. H. Pylori infection is characteristically associated with a vigorous inflammatory response and we have recently identified H. Pylori DNA in conjunctival MALT lymphoma using molecular diagnostic techniques. Ocular surface inflammation is a cardinal feature of keratoconjunctivitis sicca. Since we identified H. Pylori DNA in conjunctival MALT lymphoma we hypothesize that chronic infection may also be capable of triggering chronic ocular surface inflammation as seen in keratoconjunctivitis sicca. The purpose of this pilot study is to determine whether H. pylori DNA is detectable in the conjunctiva of seropositive KCS patients.
INCLUSION CRITERIA: Patients with ocular surface disease including aqueous or evaporative tear deficiency who are seropositive for H. pylori will be eligible. Controls will be adults without ocular surface disease who are seropositve for H. pylori. EXCLUSION CRITERIA: None listed.