This patient most likely has postoperative endophthalmitis. Other differential diagnoses to consider include other causes of endophthalmitis such as endogenous endophthalmitis, sterile endophthalmitis, panuveitis of another cause, or retained lens fragment from cataract surgery. Endophthalmitis is inflammation of the internal structures of the eye. It commonly presents as pain, injection and loss of visual acuity. Common findings on exam include mild eyelid edema, conjunctival injection, corneal edema, anterior chamber cell and flare, hypopyon (layering of inflammatory cells and exudates in inferior anterior chamber), and vitreous infiltrates.
Endophthalmitis can be divided into exogenous (post-surgical or traumatic), endogenous or sterile. Post-surgical endophthalmitis can be divided into acute (<6 weeks post-op) or delayed (>6 weeks post-op). Acute post-surgical endophthalmitis can be caused by S. epidermidis, S. aureus, or Streptococcus species. Delayed post-surgical endophthalmitis is more likely to be caused by S. epidermidis, corynebacterium, candida, or propion bacterium acnes. Causative agents of endogenous endophthalmitis include Streptococcus, S. aureus, enteric bacteria, candida, and aspergillus. Sterile endophthalmitis is often related to retained lens material or a reaction to intravitreal medications.
Work-up and treatment for endophthalmitis includes getting intravitreal and/or aqueous cultures and treatment with broad spectrum antibiotics. Ultrasound can be performed if fundus is not well visualized. If the vision is better than light perception, initial treatment of endophthalmitis usually consists of a “tap and inject”- a vitreous and/or aqueous sample is taken for culture (the tap) and then broad spectrum antibiotics are then given by intravitreal injection (the inject). If the presenting vision is light perception or worse, it is better to immediately proceed to a pars plana vitrectomy surgery. Cultures of the vitreous are taken, a vitrectomy is done, and intravitreal antibiotics are placed. Further treatment then is directed based on treatment response, culture results, and antibiotic sensitivity studies.
Because endophthalmitis can cause devastating damage to the eye, it is one of the true ophthalmology emergencies. Starting treatment as soon as possible is extremely important. Any delay may result in worse visual outcomes.