Endophthalmitis

Endophthalmitis, or endophthalmia, is inflammation of the interior cavity of the eye, usually caused by an infection. It is a possible complication of all intraocular surgeries, particularly cataract surgery, and can result in loss of vision or loss of the eye itself. Infection can be caused by bacteria or fungi, and is classified as exogenous (infection introduced by direct inoculation as in surgery or penetrating trauma), or endogenous (organisms carried by blood vessels to the eye from another site of infection and is more common in people who have an immunocompromised state). Other non-infectious causes include toxins, allergic reactions, and retained intraocular foreign bodies. Intravitreal injections are a rare cause, with an incidence rate usually less than 0.05%.
Endophthalmitis requires immediate medical attention to ensure the condition is diagnosed as soon as possible and treatment is started in order to reduce the risk of the person losing vision in the eye. Treatment options depend on the cause and whether the condition is cause by an endogenous or exogenous mechanism. For people with suspected exogenous endophthalmitis, a biopsy (virtuous tap) and treatment with antibiotics (usually by injection) is usually the first line of treatment. Once the person's response to the antibiotics is assessed, different further treatment options may be considered including surgery.
Signs and symptoms
People with endophthalmitis often have a history of recent eye surgery or penetrating trauma to the eye.
Symptoms include severe pain, vision loss, and intense redness of the conjunctiva. Hypopyon can be present and should be looked for on examination by a slit lamp. It can first present with the 'black dot sign' (Martin-Farina sign), where patients may report a small area of loss of vision that resembles a black dot or fly. Pus is often contained in the inflamed tissue of the eye (purulent).
An eye exam should be considered in systemic candidiasis, as up to 3% of cases of candidal blood infections lead to endophthalmitis.
Complications
Panophthalmitis — Progression to involve all the coats of the eye.
Corneal ulcer
Orbital cellulitis
Impairment of vision
Complete loss of vision
Loss of eye architecture
Enucleation
Cause
Bacteria: N. meningitidis, Staphylococcus aureus, S. epidermidis, S. pneumoniae, other streptococcal spp., Cutibacterium acnes, Pseudomonas aeruginosa, other gram negative organisms.
Viruses: Herpes simplex virus.
Fungi: Candida spp. Fusarium
Parasites: Toxoplasma gondii, Toxocara''.
A recent systematic review found that the most common source of infectious transmission following cataract surgery was attributed to a contaminated intaocular solution (i.e. irrigation solution, viscoelastic, or diluted antibiotic), although there is a large diversity of exogenous microorganisms that can travel via various routes including the operating room environment, phacoemulsifcation machine, surgical instruments, topical anesthetics, intraocular lens, autoclave solution, and cotton wool swabs.
Late-onset endophthalmitis is mostly caused by Cutibacterium acnes.
Causative organisms are not present in all cases. Endophthalmitis can emerge by entirely sterile means, e.g. an allergic reaction to a drug administered intravitreally.
Diagnosis
Diagnosis:
Microbiology testing.
PCR.
TASS vs Infectious endophthalmitis.
Prevention
Different approaches have been suggested to prevent exogenous endophthalmitis after cataract surgery. Perioperative antibiotic injections into the eye, specifically cefuroxime at the end of surgery, lowers the chance of endophthalmitis. Moderate evidence also supports antibiotic eye drops (levofloxacin or chloramphenicol) with antibiotic injections (cefuroxime or penicillin) to reduce the risk of endophthalmitis after cataract surgery compared with injections or eye drops alone. Periocular injection of penicillin along with chloramphenicol-suphadimidine eye drops and an intracameral cefuroxime injection with topical levofloxacin also reduces the risk reduction of developing endophthalmitis following cataract surgery for some people.
For people undergoing intravitreal injections, antibiotics are not as effective at preventing this type of infection. Studies have demonstrated no difference between rates of infection with and without antibiotics when intravitreal injections are performed. There is evidence to suggest that a solution of povidone-iodine applied pre-injection may be effective at preventing some cases of endophthalmitis in people undergoing introvitreal injections.
Treatment
Urgent medical attention is required if a person has suspected endophthalmitis. An ophthalmologist is preferred, ideally a vitreoretinal specialist. The first step in treatment (usual care) is an intravitreal injection of potent antibiotics and a biopsy to determine the type of infection. Injections of vancomycin (to kill Gram-positive bacteria) and ceftazidime (to kill Gram-negative bacteria) are routine. Even though antibiotics can have negative impacts on the retina in high concentrations, since visual acuity worsens in 65% of endophthalmitis patients and prognosis gets poorer the longer an infection goes untreated, most medical professionals make the clinical judgment decision that immediate intervention with antibiotics is necessary. People with endophthalmitis may also require an urgent surgery (pars plana vitrectomy). In some cases, evisceration may be necessary to remove a severe and intractable infection which could result in a blind and painful eye.
Steroids may be injected intravitreally if the cause is allergic. In people with acute endophthalmitis, combined steroid treatment with antibiotics have been found to improve visual outcomes, versus patients only treated with antibiotics, but any improvements on the resolution acute endophthalmitis is unknown.
References
External links
Eye diseases
Medical emergencies