Bacterial Keratitis
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
Bacterial keratitis usually manifests as a creeping ulcer. Most often it causes pneumococcus, sometimes - streptococci and staphylococci, contained in the stagnant contents of the lacrimal sac and conjunctival cavity. The direct provoking factor is usually a trauma - the introduction of a foreign body, accidental scratches of a tree branch, a sheet of paper, a dropped eyelash. Often minor damage is not noticed. For the introduction of the cocca flora, a minimal entrance gate is sufficient.
[Symptoms of bacterial keratitis
Bacterial keratitis begins acutely: lacrimation appears, photophobia, the patient can not open his eyes on his own, disturbing severe pain in the eye. On examination, a pericorneal injection of the vessels is revealed, a yellowish infiltrate in the cornea. After its disintegration, an ulcer is formed, prone to spreading. While one of its edges is epithelialized, the other remains infiltrated, dug in the form of a pocket. Within a few days, the ulcer can occupy a large area of the cornea. In the inflammatory process, the iris and ciliary body are rapidly involved, the pain in the eye and pericorneal injection increase, and the symptoms characteristic of iridocyclitis appear. Creeping ulcers are often accompanied by the formation of hypopion - a deposit of pus in the anterior chamber with a flat horizontal line. The presence of fibrin in the moisture of the anterior chamber leads to the gluing of the iris with the lens. The inflammatory process "creeps" not only over the surface, but also deep down to the Descemet's shell, which lasts longest against the lytic action of microbial enzymes. Quite often descemetocele is formed, and then perforation of the cornea. The causative agent of the creeping ulcer penetrates into the anterior chamber, substantially complicating the course of the inflammatory process. In a weakened organism and with insufficient treatment, microbes penetrate into the posterior part of the eye, causing focal or diffuse purulent inflammation in the vitreous body (endophthalmitis) or melting of all the shells of the eye (panophthalmitis). When the foci of infection appear in the vitreous body, urgent removal of purulent contents from the eye cavity (vitrectomy) with washing it with antibiotics is shown, which makes it possible to preserve the eye as a cosmetic organ, and sometimes the residual sight.
In those cases when the inflammatory process subsides after the perforation of the cornea, a gross corneal thorn appears, usually fused with the iris.
With a creeping ulcer, there are no longer growing vessels. With the advent of neovascularization, the scarring process is faster.
What do need to examine?
Treatment of bacterial keratitis
Prevention of exogenous keratitis should be carried out with any, even minor injury of the cornea: a mote, an eyelash, an accidental slight scratch. In order that the erosion of the cornea does not become an entrance gate for infection, it is enough to drip into the eye any antibacterial eye drops 2-3 times a day, and put an eye ointment with antibiotics for a night. It should also be done by providing first aid to a patient who has superficial keratitis, only instillations of antibacterial drops should be performed every hour until the patient gets to see a specialist. If the diagnosis of keratitis is made at a doctor with an ophthalmologist, first a smear of the contents of the conjunctival cavity or a scraping from the surface of the corneal ulcer is taken to identify the causative agent of the disease and determine its sensitivity to antibacterial drugs, then prescribe a treatment aimed at suppressing infection and inflammatory infiltration, improving trophism cornea. Antibiotics are used to suppress infection: levomitsetin, neomycin, kanamycin (drops and ointment), tsipromed, okakcin. The choice of antimicrobials and their combination depend on the type of pathogen and its sensitivity to drugs.
In severe cases, sulfanilamide preparations and antibiotics are administered under conjunctive or parabulbar, following the recommended dosages.
For the prevention of iridocyclitis, appoint installations of mydriatic. The frequency of their instillation is individual and depends on the severity of inflammatory infiltration and the reaction of the pupil.
Steroid drugs are prescribed topically during the resorption of inflammatory infiltrates after epithelializing the surface of the ulcer. At this time, drugs containing a broad-spectrum antibiotic and a glucocorticoid (garazone) are effective. Along with these preparations, proteolysis inhibitors, immunocorrectors, enterigistamine and vitamin preparations are applied topically and inward, as well as agents that improve trophic and corneal epithelialization (balarpan, taufon, solcoseryl, actovegin, carnosine, ethadene, etc.).