Page 27 of 27

OP3.1-7 | Conjunctiva and Red Eye — PBL Case

CLINICAL SETTING

Dr. Priya Menon is a final-year MBBS student posted at the ophthalmology outpatient department of a district hospital in coastal Karnataka. On a busy Monday morning, she is asked to see three consecutive patients presenting with red eyes. The patients are very different from each other — and the attending ophthalmologist has told her: 'By the end of this clinic, I want you to be able to tell me exactly why each of these patients has a red eye, what makes each one dangerous or benign, and what you would do for each.' Dr. Priya begins her assessments.

Trigger 1: Patient 1: The Sticky Eye

Patient 1 is Ramesh, a 28-year-old auto-rickshaw driver. He presents with a 3-day history of a red, sticky left eye with a yellow-green discharge that crusts over his eyelids overnight. He has mild grittiness but no significant pain, no photophobia, and his vision feels 'fine.' He mentions a similar episode 6 months ago that 'cleared on its own.' On examination: VA is 6/6 OU. The left conjunctiva shows diffuse hyperaemia. On eversion of the upper lid, Dr. Priya sees flat, polygonal velvety elevations on the tarsal conjunctiva. There is no preauricular lymphadenopathy. The cornea is clear. Patient 2 then enters: Kavitha, a 25-year-old teacher, has had a red, watery, painful right eye for 5 days. She had a 'cold' one week ago. Her right eye is tearing profusely with no discharge. A tender, pea-sized lump is palpable in front of her right ear. On eversion of her upper lid, Dr. Priya sees small, translucent, dome-shaped elevations on the palpebral conjunctiva.

DISCUSSION POINTS

What is the correct term for the elevations seen on Ramesh's tarsal conjunctiva, and what cell type is responsible for them? How do they differ structurally from the elevations seen in Kavitha's examination?
Construct a table comparing Ramesh's and Kavitha's presentations across these parameters: discharge type, conjunctival reaction, preauricular lymphadenopathy, likely causative organism/agent, and recommended first-line treatment.
The clinical trap: Kavitha is prescribed a topical antibiotic by a junior doctor. Identify and explain the error. What antibiotic-resistance concern does this practice raise in the Indian context?
What hygiene and infection control advice would you give each patient, and why does viral conjunctivitis carry a higher institutional outbreak risk than bacterial conjunctivitis?
What feature, if present in either patient, would make you immediately change your management plan and refer to a specialist rather than prescribing in primary care?

Click to reveal Trigger 2: Patient 3: Danger Signs and a Difficult History (discuss previous trigger first!)

Trigger 2: Patient 3: Danger Signs and a Difficult History

Patient 3 is Suresh, a 40-year-old schoolteacher. He presents with a red right eye for 10 days. He visited a pharmacist who gave him chloramphenicol drops, but the eye has not improved. Suresh reports aching periocular pain (not gritty), marked photophobia, and that his vision has been blurred for the past week. He denies any discharge. He has a history of recurrent low back pain diagnosed as ankylosing spondylitis 2 years ago. On examination: VA is 6/6 OS, 6/24 OD. Circumcorneal injection (ciliary flush) is present. The cornea appears slightly hazy. There is no preauricular node and no discharge. Dr. Priya realises this is not conjunctivitis. She is about to examine Suresh further when she notices a 4th patient has been waiting: an 8-year-old boy named Aditya, brought by his grandmother. Aditya has been rubbing his eyes constantly for 3 months, mostly during the day. Both eyes are red, with intense itching, and a stringy, white, mucoid discharge. On examination: large, flat-topped papillae are visible on the upper tarsal conjunctiva (the grandmother says they look 'like cobblestones' because the ophthalmologist told her last year). Whitish chalky dots are visible at the limbus.

DISCUSSION POINTS

Identify the specific red-eye danger signs present in Suresh's case. Explain the pathophysiology of each: why does anterior uveitis cause photophobia (as opposed to the mild photophobia of conjunctivitis)? Why does it reduce visual acuity?
How does Suresh's history of ankylosing spondylitis inform the diagnosis? Name two other systemic diseases that classically cause anterior uveitis and describe the ocular HLA association for ankylosing spondylitis-associated uveitis.
What is the immediate management priority for Suresh at the district hospital level before specialist review? Explain the rationale for cycloplegia in anterior uveitis.
For Aditya: identify the specific conjunctival signs described and name the specific form of allergic conjunctivitis. Explain the dual immune mechanism (Type I and Type IV hypersensitivity) responsible for his presentation.
Compare the immune targets and expected response to treatment: why do topical antihistamines alone fail to control Aditya's condition, and what treatment escalation is required for an acute exacerbation?

Click to reveal Trigger 3: Community Clinic: Trachoma, Pterygium, and a Procedure (discuss previous trigger first!)

Trigger 3: Community Clinic: Trachoma, Pterygium, and a Procedure

Dr. Priya is next posted to a rural vision camp in a fishing community 40 km from the district hospital. She encounters two more presentations. The first is a 55-year-old fisherman, Moideen, with a wing-shaped fleshy growth on the nasal side of his right eye that he has had 'for years.' It is growing slowly toward the pupil. VA is 6/9 OD. A probe passed under the growth cannot pass freely at the nasal margin (the growth is adherent there). The second patient is a 60-year-old woman, Fatima, from the same community, whose child has already been graded TF by a health worker. Fatima herself has inward-turning eyelashes on her left upper lid that she has been pulling out herself for the past year; Dr. Priya also notes a white corneal opacity occupying the central pupillary zone. A 14-year-old boy presents last with a foreign body sensation in his right eye after working in a rice field. Fluorescein staining reveals vertical linear abrasions on the right cornea.

DISCUSSION POINTS

Apply the probe test to Moideen: what does it confirm? Explain the pathogenesis of pterygium starting from UV-B exposure at the limbus — trace the sequence from limbal stem cell damage to fibrovascular invasion of the cornea.
What are the indications for surgical excision of pterygium? At what corneal extent would you recommend surgery for Moideen? What post-operative advice reduces recurrence risk?
For Fatima: record the correct WHO trachoma grades for her. Explain the pathological mechanism by which repeated Chlamydia trachomatis infection progresses from TF to TT to CO — what structures are involved at each stage?
Explain the significance of vertical linear corneal abrasions in the 14-year-old. Where is the foreign body most likely lodged? Describe the step-by-step technique for removing a subtarsal foreign body at a primary care level, including the role of topical anaesthesia and lid eversion.
What red-flag features in any foreign-body presentation would make you STOP the procedure and refer emergently? Apply these criteria to decide: if the same 14-year-old had reduced vision and a shallow anterior chamber, what would you do differently and why?

Learning Issues

Research these questions and bring your findings to the discussion.

[]
[]
[]
[]
[]
[]
[]
[]