Uveitis and intraocular inflammation
Uveitis questions test classification, targeted investigation and steroid judgement. The exam wants the standardized nomenclature, the granulomatous versus non-granulomatous distinction, and the masquerade diagnoses that punish reflexive immunosuppression.
Classification and signs
The standardized nomenclature defines onset, duration, course and location: anterior, intermediate, posterior and panuveitis. Core findings are anterior chamber cells and flare, keratic precipitates, posterior synechiae and cystoid macular oedema. Granulomatous disease gives mutton-fat keratic precipitates with Busacca or Koeppe nodules; non-granulomatous gives fine precipitates. HLA-B27 acute anterior uveitis is sudden, unilateral and non-granulomatous. Fuchs heterochromic uveitis is chronic, unilateral, with heterochromia and no synechiae.
Causes you must name
Anterior: HLA-B27 disease, herpes, Fuchs, trauma, lens-induced. Intermediate: pars planitis, sarcoidosis, multiple sclerosis, lymphoma. Posterior: toxoplasmosis with a focal retinochoroiditis beside a scar, CMV retinitis in the immunosuppressed, sarcoidosis, Vogt-Koyanagi-Harada disease with bilateral serous detachments, Behçet disease with hypopyon and retinal vasculitis, and sympathetic ophthalmia after penetrating trauma. Intraocular lymphoma is the classic masquerade in chronic unilateral vitritis in older adults.
Investigation and treatment
Investigations follow the history and phenotype rather than a fixed panel; a first unilateral non-granulomatous anterior uveitis in a healthy adult usually needs none. Treat anterior disease with topical steroid and a cycloplegic, posterior and intermediate disease with periocular or systemic steroid, then steroid-sparing agents such as methotrexate or mycophenolate, and biologics. Treat infective causes specifically.
Worked example
A 35-year-old has a painful red left eye with fine keratic precipitates, 2+ cells, a quiet right eye and low back pain. Reasoning: acute unilateral non-granulomatous anterior uveitis with sacroiliitis suggests HLA-B27 disease; treat with topical steroid and cycloplegia, ask about psoriasis and bowel disease, and refer the back pain rather than ordering a broad serology panel.
Traps
Ordering a fixed uveitis screen; missing lymphoma in chronic unilateral vitritis; using steroids in herpetic keratouveitis without antiviral cover; forgetting to dilate.