Review of the ophthalmic manifestations of gout and uric acid crystal deposition

Abstract

Gout is a clinical disorder that is characterized by the deposition of monosodium urate crystals (MSU) in joints and tendons, usually in the presence of prolonged hyperuricaemia. Following an asymptomatic phase of hyperuricaemia, gout usually presents as acute monoarthritis followed by periods of remission and exacerbation. Conjunctival hyperaemia and subconjunctival haemorrhage exacerbated by purine intake are two of the more common manifestations that may go unrecognized. Other ocular and adnexal structures can be affected by urate crystal deposition and associated inflammation, with potentially vision-threatening consequences; however, ocular manifestations of gout are rare and may have been over-reported in the older literature, but our understanding of the clinic-pathological features of ocular urate deposits remains limited.

Systemic Urate Deposition: An Unrecognized Complication of Gout?

“…Urate deposits have been reported in nearly all ocular and adnexal structures including the eyelid [ 55 ], medial and lateral canthus [ 56 , 57 ], conjunctiva [ 58 ], sclera [ 59 ], cornea [ 60 ], lens, iris [ 61 ], orbital fossa [ 62 ], and retina [ 63 ]. The eyes may be predisposed to tophi secondary to lower body temperatures and a low pH environment resulting in poor solvent capabilities [ 61 , 64 ].…”

“…Urate deposition in the sclera and episclera may manifest as anterior and posterior scleritis, tenonitis or nodular and recurrent episcleritis [ 64 ]. Scleral tophi may present as chalky white lesions on the scleral surface ( Figure 4 A) [ 59 ].…”

“…Scleral tophi may present as chalky white lesions on the scleral surface ( Figure 4 A) [ 59 ]. Tophi have been seen in all layers of the cornea including the corneal epithelium, stroma and Bowman’s layer and may lead to corneal ulcers ( Figure 4 B) [ 60 , 64 ]. MSU deposits in the iris and the anterior chamber have been reported as clear, gelatinous deposits on the surface of the iris and anterior chamber angle [ 59 , 61 ].…”

“…Another case report described subretinal crystal deposits with adjacent regions of macular atrophy on fundoscopic exam and fluorescein angiogram in a patient with tophaceous gout presumed to be urate crystals [ 63 ] ( Figure 4 C,D). Recurrent uveitis has been seen in gout patients and may resolve with colchicine and corticosteroids [ 64 ].…”

Corneal Perforation in a Patient with Chronic Keratouveitis and Gout: Case Report

“…7In the 1960s gout was estimated to cause 1-3.5% of all uveitis but recently the prevalence of gout-related uveitis has decreased. (1) In most of these cases that we have observed from medical literature serum urate level is unknown and clinical course of ocular involvement was bilateral with recurrent attacks. (6) Usually between attacks the eye appears normal although there may be posterior synechiae formation.…”