12-phase flow (12)

1. 1FRAME
   Frame as SUN-classified intraocular inflammation by anatomic site; state that vision-threatening look-alikes (angle closure, keratitis, scleritis, endophthalmitis, intraocular-lymphoma masquerade) and the systemic-disease engines are recognised and routed OUT by engine_id, not re-authored here. Establish the over-arching guardrail: treatable infectious causes are excluded before / alongside immunosuppression (AAO IMT guidance 2017/2018; Sharma Int J STD AIDS 2024).
   advance: uveitis scope + SUN frame confirmed; not-this-engine concerns route-mapped by engine_id
2. 2ENTRY
   Recognise the presentation and assign the SUN anatomic class (anterior/intermediate/posterior/pan), laterality, and chronicity up front — these select the cause list and the work-up (Jabs Am J Ophthalmol 2005; SUN 2021 Classification Criteria).
   inputs: anatomic_class_anterior_intermediate_posterior_pan, laterality_and_chronicity
   actions: workup.acute_red_eye
   advance: entry trigger present; SUN class + laterality + chronicity recorded
3. 3CONTEXT
   Pattern + association substrate: granulomatous vs non-granulomatous KP morphology, hypopyon, pain/photophobia vs painless, systemic review (SpA/sarcoid/Behçet/IBD), infectious exposure (TB/syphilis/HSV/toxo/CMV), paediatric JIA status. This phase builds the Bayesian pretest map by SUN pattern (SUN 2021; AAO uveitis guidance).
   inputs: granulomatous_vs_nongranulomatous_kp, hypopyon_present, pain_photophobia_vs_painless, systemic_review_spa_sarcoid_behcet_ibd, infectious_exposure_tb_syphilis_hsv_toxo, pediatric_jia_status
   actions: workup.lymphadenopathy
   advance: SUN pattern + systemic/infectious pretest priors assigned
4. 4RED_FLAGS
   Screen vision-threatening look-alikes and route OUT by engine_id: fixed mid-dilated pupil + cloudy cornea + high IOP → ophtho.acute-angle-closure-glaucoma.core.v1; corneal infiltrate/dendrite → keratitis; boring pain + scleral tenderness → scleritis; post-procedure/endogenous hypopyon with retinitis → endophthalmitis (sight-threatening, vitreous tap + intravitreal antibiotics — not managed here). Capture IOP (uveitic-glaucoma surveillance starts now).
   inputs: vision_threatening_red_flags, intraocular_pressure
   actions: workup.acute_vision_loss
   advance: vision-threatening mimics screened; routed OUT by engine_id if positive; IOP recorded
5. 5INITIAL_WORKUP
   TARGETED (not shotgun) work-up driven by SUN pattern. Near-universal in non-trivial/recurrent/posterior disease: treponemal + non-treponemal syphilis serology and IGRA/TST (the treatable-infectious + pre-immunosuppression screen). Slit-lamp SUN grading of anterior-chamber cells/flare and vitreous haze; dilated fundus for chorioretinal lesions/vasculitis (Sharma 2024; AAO IMT guidance; SUN Jabs 2005).
   inputs: syphilis_serology_treponemal, igra_or_tst_tb
   actions: panel.cbc, panel.inflammation
   advance: SUN grading documented; syphilis + TB screen sent; infectious guardrail activated
6. 6BRANCHING_WORKUP
   Pattern-directed cascade: unilateral-acute-non-granulomatous → HLA-B27 (→ rheum.spondyloarthropathy.core.v1); bilateral-granulomatous → ACE + chest CT (sarcoid), QuantiFERON + chest imaging (TB → id.tuberculosis.core.v1); posterior focal retinochoroiditis → toxoplasma serology; posterior necrotising retinitis in immunocompromised → CMV/HSV-VZV; positive syphilis serology → id.syphilis.core.v1. OCT macula for CME; consider diagnostic vitrectomy/aqueous tap if masquerade (intraocular lymphoma in the elderly) suspected (SUN 2021; Sharma 2024).
   inputs: ace_and_chest_imaging_sarcoid, hla_b27, oct_macula_for_cme
   actions: workup.lymphadenopathy, panel.cmp
   advance: cause-specific tests resolved or masquerade/infection routed by engine_id
7. 7DIFFERENTIAL
   Terminal differential with named pivots: HLA-B27 acute anterior uveitis (unilateral, recurrent, fibrinous, hypopyon, +HLA-B27 pivot) vs HSV/VZV anterior (sectoral iris atrophy + raised IOP + corneal scar pivot) vs sarcoid (bilateral granulomatous mutton-fat KP + hilar adenopathy pivot) vs Behçet (hypopyon + retinal vasculitis + oral/genital ulcers pivot) vs JIA (asymptomatic chronic paediatric anterior, band keratopathy pivot) vs toxoplasma (focal retinochoroiditis adjacent to old scar pivot) vs syphilis/TB (any pattern — serology/IGRA pivot) vs intraocular lymphoma (elderly, vitreous cells, steroid-refractory — vitreous biopsy pivot). Distinguish from conjunctivitis / angle closure / keratitis / scleritis / endophthalmitis (SUN 2021 Classification Criteria).
   advance: single best uveitic diagnosis selected (or infectious/masquerade routed); infection status known before immunosuppression
8. 8RISK_STRATIFICATION
   Sight-threat stratification: anatomic site (posterior/pan > intermediate > anterior risk), CME on OCT, optic-nerve/macular involvement, hypotony, uveitic glaucoma, bilaterality, paediatric JIA (high silent-complication burden — Grassi 2007). Posterior/pan and chronic non-infectious sight-threatening disease escalate the treatment tier. Systemic-toxicity calculators support the inpatient infectious-uveitis subset.
   inputs: oct_macula_for_cme, intraocular_pressure
   actions: calc.news2
   advance: sight-threat tier + site-specific treatment route assigned
9. 9TREATMENT
   Tiered, infection-gated treatment: (1) INFECTIOUS — pathogen-directed therapy first (aciclovir/valaciclovir for HSV/VZV; pyrimethamine-sulfadiazine/co-trimoxazole for toxoplasma; pen-G/route to id.syphilis.core.v1; route TB to id.tuberculosis.core.v1) — corticosteroid only with antimicrobial cover; (2) NON-INFECTIOUS ANTERIOR — topical prednisolone acetate 1% with taper + cycloplegic (cyclopentolate/atropine) to relieve ciliary spasm and prevent posterior synechiae; (3) escalate sight-threatening intermediate/posterior/pan — periocular/intravitreal triamcinolone or dexamethasone implant, or systemic prednisone; (4) CHRONIC non-infectious steroid-dependent → steroid-sparing antimetabolite (methotrexate/mycophenolate; methotrexate favoured for posterior/pan in FAST) and biologic (adalimumab) for refractory/sight-threatening — TB/HBV/syphilis screened FIRST. Gate teratogens in pregnancy (FAST JAMA 2019; VISUAL Lancet 2016; POINT Ophthalmology 2018; SYCAMORE NEJM 2017).
   inputs: pregnancy, cbc_lft_renal_before_antimetabolite, igra_or_tst_tb
   advance: infection excluded/treated; site-appropriate anti-inflammatory tier started; steroid-sparing plan set if chronic non-infectious
10. 10DISPOSITION
    Isolated mild non-granulomatous anterior uveitis → outpatient ophthalmology with topical therapy + 1-week review. Sight-threatening posterior/pan, hypopyon with systemic Behçet, infectious posterior uveitis needing IV therapy, or paediatric severe JIA uveitis → urgent uveitis-specialist referral ± admission (e.g., IV antimicrobial/IV methylprednisolone). Suspected endophthalmitis/angle-closure/lymphoma masquerade → route OUT by engine_id same-day (SUN 2021; AAO).
    inputs: vision_threatening_red_flags
    advance: disposition documented; specialist referral/admission/route-out actioned
11. 11MONITORING
    Active-inflammation monitoring on the SUN scale: serial anterior-chamber cell/flare and vitreous-haze grading to "inactive"; IOP at every visit (steroid-response AND uveitic glaucoma — implant carries ~4-fold IOP risk and ~3-fold glaucoma in MUST, Friedman 2013 / MUST 2015); OCT for CME response (POINT). Steroid-sparing safety: CBC/LFT/renal on antimetabolites (FAST — LFT elevation the commonest AE); biologic infection vigilance. Counsel that corticosteroid taper is gradual to avoid rebound.
    inputs: oct_macula_for_cme, cbc_lft_renal_before_antimetabolite, intraocular_pressure
    actions: panel.cmp
    advance: inflammation trending to inactive on SUN grading; IOP/CME/IMT-safety surveillance running
12. 12FOLLOWUP
    Chronic-disease arc (the deep tail of this engine): structured corticosteroid-sparing taper to ≤7.5 mg prednisone with sustained inactivity (FAST endpoint); long-term antimetabolite/biologic continuation with periodic CBC/LFT/renal + biologic infection surveillance; recurrence counselling and rapid-access pathway for HLA-B27 recurrent AAU; complication surveillance and management routing — uveitic glaucoma (→ ophtho.acute-angle-closure-glaucoma.core.v1 for secondary glaucoma), cataract, band keratopathy, persistent CME, hypotony; PAEDIATRIC JIA asymptomatic-uveitis screening slit-lamp schedule by ANA/age/subtype with early methotrexate/adalimumab (Grassi J Rheumatol 2007; Wennink Acta Ophthalmol 2022 — earlier IMT improved outcomes; Ramanan NEJM 2017). Co-manage the systemic association via its engine_id.
    inputs: pediatric_jia_status, systemic_review_spa_sarcoid_behcet_ibd
    advance: steroid-sparing maintenance + complication-surveillance + paediatric screening plan documented; systemic association co-managed by engine_id