Phacoanaphylaxis Differential Diagnoses

Updated: Jun 10, 2021
  • Author: Robert H Graham, MD; Chief Editor: John D Sheppard, Jr, MD, MMSc  more...
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Diagnostic Considerations

Phacoanaphylactic endophthalmitis or lens-induced uveitis may be difficult or impossible to distinguish from other causes of inflammation based on any one clinical sign, but the clinical setting of retained lens material after cataract surgery usually permits the ophthalmologist to make the correct diagnosis. Similarly, rupture of the lens capsule following trauma also points to a lens-induced inflammation. If the eye is injured severely, requiring enucleation, the presence of phacoanaphylaxis often is masked. According to a study by Thatch and Marak, from 144 histologically verified cases of phacoanaphylactic endophthalmitis, in only 6 cases was the diagnosis correct clinically before enucleation. [29]

Posttraumatic endophthalmitis

Endophthalmitis occurs following 2-7% of penetrating injuries. The incidence is higher in association with intraocular foreign bodies, particularly vegetable matter, while the incidence is lower with hot metallic projectiles. Posttraumatic endophthalmitis can progress rapidly. Clinical signs often include marked inflammation with fibrin, hypopyon, and retinal phlebitis. In general, the larger and more contaminated the injury, the more likely endophthalmitis will develop. Anterior chamber tap and vitreous tap should be performed, and intravitreal antibiotic injections should be administered. [43, 44]

Sterile (aseptic) endophthalmitis

Postoperative inflammation occurring in the absence of infection may be acute or chronic and mild to moderately severe. [45] The onset of aseptic endophthalmitis is usually 3-4 days after surgery. Exceptionally, sterile endophthalmitis may occur weeks or months after intraocular surgery, as with late rupture of the anterior hyaloid membrane and vitreous adhesion to the wound in aphakic patients, degradation of implant materials, withdrawal of topical steroid therapy, or dislocation of an intraocular lens (IOL). [46, 47, 48] It can present with hypopyon and cloudy vitreous, but usually no corneal edema, chemosis, or lid swelling is present. Unlike bacterial infections, aseptic endophthalmitis is not severely and progressively painful. Secondary aseptic endophthalmitis often is related to toxic foreign materials inoculated or implanted into the eye at the time of intraocular surgery.

Sympathetic ophthalmia

Clinically, sympathetic ophthalmia presents as a rare bilateral uveitis with an insidious onset and a progressive course. [49, 50, 51, 52, 53, 54, 55] It almost invariably follows a penetrating wound involving uveal tissue produced by either ocular trauma or intraocular surgery. Sympathetic ophthalmia also may occur with laser ciliary ablation procedures, particularly direct contact lasers. Involvement of the noninjured (nonoperated) eye in this disease makes the clinical diagnosis somewhat more straightforward.

The interesting association between phacoanaphylactic endophthalmitis and sympathetic ophthalmia is based upon histopathologic studies. Easom and Zimmerman reviewed 400 cases of sympathetic ophthalmia from the Armed Forces Institute of Pathology and found 7 pairs of eyes with sympathetic ophthalmia. [56, 57] Among them, 2 of the 7 inciting eyes and 6 of the 7 sympathizing eyes demonstrated the classic histopathologic appearance of phacoanaphylactic endophthalmitis instead of sympathetic ophthalmia.

The association of phacoanaphylactic endophthalmitis in sympathetic ophthalmia may be caused by secondary alteration of the lens capsule in sympathetic ophthalmia, or the 2 diseases may be synergistic. One differentiating feature may be the choroidal thickening observed in sympathetic ophthalmia on ultrasound because only minimal choroidal inflammation and thickening occur, even in severe forms of phacoanaphylactic endophthalmitis. [58]

Phacolytic glaucoma

The leakage of lens proteins from mature and hypermature cataracts characterize phacolytic glaucoma. [59, 27, 60, 61, 62] This leakage often is associated with pain, light sensitivity, and marked anterior chamber reaction. The trabecular meshwork becomes blocked by macrophages and high molecular weight proteins, and then increased intraocular pressure develops. Definitive treatment requires cataract surgery.

Differential Diagnoses