This study will examine whether infection with Helicobacter pylori bacteria may cause
inflammation of the eye's surface. Although most people who are infected with H. pylori do
not have symptoms, the bacteria can cause several diseases, including gastritis-stomach
inflammation, stomach ulcers or, rarely, stomach cancer, and certain types of lymphoma. H.
pylori has also been associated with autoimmune disorders, in which the patient's immune
system attacks the body's own tissues.
People who have been infected with H. pylori, with and without dry eye, may be eligible for
this study. Candidates are screened with a medical history, a blood test to determine H.
pylori infection, and an eye examination. The examination includes measurements of visual
acuity, eye pressure, and tear production. To measure the amount of tear production, a small
piece of filter paper is inserted over the eyelid on the side and collects tears over a
5-minute period. Drops of two colored dyes (orange and green) are placed in the eyes to see
if there are any dry areas. Screening also includes examination of the pupils and eye
movements, the lens, and the back of the eye, including the retina.
Participants will also have a few cells collected from the surface of the eye. After the
eyes are numbed with anesthetic eye drops, a swab (like a Q-tip) is rolled over the surface
of the white part of the eye to collect small samples of the superficial layer of the
conjunctiva - a transparent membrane covering the eyeball. The specimens are analyzed by
special laboratory techniques to determine whether H. pylori has infected the eye.
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.
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.