A 19-year-old man comes to the office due to eye pain and blurry vision in both eyes for the last several days. He sustained an open globe injury to the right eye 3 months ago after being struck during an altercation and was treated with surgical repair and prophylactic antibiotics. The left eye was unaffected. At the patient's last follow-up appointment, visual acuity in the right eye had improved from 20/400 to 20/80. He is otherwise healthy. Temperature is 37.1 C (98.8 F). Examination is unremarkable apart from bilateral conjunctival injection and decreased visual acuity in both eyes. Analysis of vitreous samples from both eyes demonstrates multinucleated giant cells. Which of the following mechanisms is most likely causing this patient's current manifestations?

Question

A 19-year-old man comes to the office due to eye pain and blurry vision in both eyes for the last several days.  He sustained an open globe injury to the right eye 3 months ago after being struck during an altercation and was treated with surgical repair and prophylactic antibiotics.  The left eye was unaffected.  At the patient's last follow-up appointment, visual acuity in the right eye had improved from 20/400 to 20/80.  He is otherwise healthy.  Temperature is 37.1 C (98.8 F).  Examination is unremarkable apart from bilateral conjunctival injection and decreased visual acuity in both eyes.  Analysis of vitreous samples from both eyes demonstrates multinucleated giant cells.  Which of the following mechanisms is most likely causing this patient's current manifestations?

Quizplus · Accepted Answer

This patient with a traumatic injury to the right eye has developed granulomatous inflammation of both the injured and noninjured eye, a condition known as sympathetic ophthalmia. This occurs when there is a robust T-cell response to previously sequestered antigens in the eye, an area that displays immune privilege. Certain anatomic sites (eg, eyes, testes) have inherent immune privilege, in which inflammation is inhibited to limit consequent organ dysfunction. Self-antigens located in sites with immune privilege can be recognized by T cells that escape negative selection in the thymus. Therefore, if these antigens are released into the lymphatic system through trauma, T cells may recognize these antigens as foreign and mount a response that can occur in both the injured eye and the contralateral eye. Because of this potential sight-threatening condition, if an eye is severely injured with no prognosis for recovery of vision, it is surgically removed (ie, enucleated) to prevent blindness in the uninjured eye. However, in patients whose vision is likely to recover, treatment is focused on decreasing inflammation (eg, corticosteroids) should the condition develop. (Choice A) Herpes zoster reactivation can cause granulomatous keratouveitis (ie, anterior chamber inflammation). However, herpes zoster typically reactivates in a single ganglion, leading to unilateral symptoms. (Choice B) Spondyloarthritis may be triggered by a gastrointestinal pathogen and result in a mixed inflammatory reaction that leads to reactive arthritis and uveitis. However, it is not triggered by previous ocular trauma. (Choice C) Infectious agents can be introduced during trauma or surgery, which can result in an acute intraocular infection that prompts a neutrophilic response. However, this would not affect the contralateral eye. (Choice E) Although rare, a type IV hypersensitivity reaction to an antibiotic may cause bilateral uveitis. However, this would occur near the time of antibiotic administration, not 3 months later. Educational objective: Traumatic injury to the eye, a site that displays immune privilege, can lead to the release of previously sequestered antigens that T cells recognize as foreign. This can lead to sight-threatening inflammation in both the injured and uninjured eye.

A 19-Year-Old Man Comes to the Office Due to Eye