ByKara C. LaMattina, MD, Boston University School of Medicine
Reviewed/Revised Sep 2022

Endophthalmitis is infection inside the eye. It is a medical emergency.

  • Eye surgery, eye injury, or infection in the bloodstream can cause the infection.

  • Severe eye pain, eye redness, and loss of vision may occur.

  • Cultures are taken of eye fluids, and antibiotics are given as soon as possible.

Endophthalmitis is uncommon. It is caused by organisms that have entered the eye through a surgical incision or an injury to the eyeball or, less often, have traveled through the bloodstream into the eye. Infection in the bloodstream has many possible causes, such as dental procedures, intravenous drug abuse, an abscess (a pocket of pus), skin ulcers, infections such as pneumonia or sepsis, or surgery anywhere in the body.

Infection that causes endophthalmitis is usually due to bacteria (such as Staphylococcus aureus), but fungi or protozoa may also be responsible. Viruses can also cause extensive eye infections, but these are not usually classified as endophthalmitis.

Symptoms of Endophthalmitis

Endophthalmitis symptoms may be severe and include severe eye pain, redness in the white of the eye, extreme sensitivity to bright light, decreased vision, and occasionally swelling of the eyelid.

Diagnosis of Endophthalmitis

  • A doctor's examination of the eye

  • Cultures of samples from the eye

  • Blood and urine cultures

The diagnosis of endophthalmitis is based on the symptoms, an examination of the eye, and cultures to identify the organism causing the infection. Cultures may be taken from the aqueous humor (fluid inside the front of the eye, also called the aqueous) and the vitreous humor (the jellylike substance that fills the back of the eyeball, also called the vitreous) to determine which organisms are causing the infection and which drugs are most active against them. People may also need blood and urine cultures.

Prognosis for Endophthalmitis

Even with early and appropriate treatment, the prognosis for vision is often poor.

Treatment of Endophthalmitis

  • Antibiotics

  • Sometimes corticosteroids or surgery

Endophthalmitis is a medical emergency.

Immediate treatment with antibiotics is usually needed to preserve vision and to protect the health of the eye. A delay of even a few hours can result in irreversible vision loss in extreme cases. The choice of antibiotic may be adjusted depending on which organism is found to be causing the endophthalmitis. Antibiotics may be injected into the eye, given by vein (intravenously), or both.

People who have very poor vision when they are seen by a doctor may be given corticosteroids or have surgery. Corticosteroids can be given by mouth for a few days after the antibiotic injection or they can be injected into the eye. Surgery may be needed to remove infected tissue from inside the eye, which may improve the chances of stopping the infection.

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