The formation of an oval-shaped ulcer at the margin of the cornea is also a sign.Symptoms of PUK include pain, redness, tearing, increased sensitivity to bright light, impaired or blurred vision, and the feeling of foreign objects trapped in the eyes. Association
There are several associations of PUK to ocular and systemic diseases. Rheumatoid arthritis (RA),  Wegners granulomatosis (WG), and Polyarteritis Nodosa (PAN) are the most common systemic conditions. Rheumatoid arthritis: Approximately 50% of PUK are related to collagen vascular diseases, in which RA is the most common category. Around 34-42% of PUK patients have RA. Wegners granulomatosis: WG is a rare autoimmune disease associated with PUK. It causes vasculitis of the lower and upper respiratory tracts, and it also affects multiple organs, including eyes. Without timely initiation of systemic therapy, WG patients will develop conjunctival and scleral inflammations. The inflammation will eventually cause corneal thinning and worsen PUK. Polyarteritis Nodosa: PAN is another autoimmune disease in which the bodys immune system attacks small and medium-sized arteries of its own by mistake. PUK is one of the predominant ocular inflammatory manifestations of PAN. Causes
There are three major causes for PUK. One possible cause is injury due to any kind of scratches by sharp or hard objects on the surface of the cornea. The scratched area forms an opening in the cornea, allowing microorganisms to access the cornea and lead to infection.
In addition, conjunctival resection can be performed to temporarily remove local inflammatory mediators, followed by the use of immunosuppressants. Prognosis
Currently, there are limited studies regarding the prognosis of PUK. However, one study has pointed out possible complications surrounding PUK include moderate to severe vision loss, corneal perforation and increased risk of recurrence. Epidemiology
PUK is a rare condition with an estimated incidence of 3 per million annually. Studies have reported that most patients with PUK are older than 60 years of age (32%). Among them, men have a higher occurrence rate in men (60%). Most patients live in rural areas (66%) and are in the lower socioeconomic groups. The age of those with PUK ranges from 5 to 89 years, with a mean age of 45.5 years.The mortality rate after PUK diagnosis in an investigation of 34 patients with and without immunosuppressive medication is 53% and 5%, respectively. Another single-centre study involving 46 patients with RA reported a mortality rate of 15%. Reports have also shown a possibility of PUK occurrence after any ocular surgery. In a retrospective study of 771 eyes, 1.4% of participants reported developing late-onset PUK at an average of 3–6 months after surgery. == References ==