12-phase flow (12)

1. 1FRAME
   Frame as ACUTE CONJUNCTIVITIS subtyping (viral vs bacterial vs allergic) layered on a mandatory sight-threatening-red-eye screen. Most acute infective conjunctivitis is self-limited (Sheikh Cochrane 2012; Everitt BMJ 2006), so the engine is a discriminator + antibiotic-stewardship + red-flag-routing tool. Gonococcal/chlamydial/neonatal/contact-lens cases are NOT simple conjunctivitis and are escalated. Keratitis, uveitis, angle-closure, scleritis are recognised then routed OUT by engine_id.
   advance: conjunctivitis scope confirmed; not-this-engine sight-threatening concerns routed by engine_id
2. 2ENTRY
   Recognise the entry pattern: undifferentiated red eye + discharge, vs bilateral itchy (allergic), vs unilateral watery + preauricular node (adenoviral/EKC), vs hyperacute copious purulent (gonococcal emergency), vs neonate (ophthalmia neonatorum), vs contact-lens wearer (keratitis-until-excluded).
   advance: entry pattern captured; emergency/neonatal/contact-lens flags raised early
3. 3CONTEXT
   Build the subtype prior: discharge character (watery/mucopurulent/hyperacute-purulent/ropy), itch dominance, morning glued lids, laterality + fellow-eye spread, tender preauricular node, contact-lens use, sexual/STI history, neonate age in days, immunocompromise, institutional/sick-contact exposure. This phase assigns the pre-test viral-vs-bacterial-vs-allergic probability (Rietveld BMJ 2004; Azari JAMA 2013).
   inputs: discharge_character, itch_dominance, morning_glued_eyelids, laterality_and_spread, preauricular_lymphadenopathy, contact_lens_use, sexual_history_or_genital_symptoms, neonate_age_days, immunocompromise, recent_sick_contact_or_institutional_exposure
   actions: workup.lymphadenopathy
   advance: subtype pre-test prior assigned (viral / bacterial-nongono / gonococcal / chlamydial / allergic)
4. 4RED_FLAGS
   MANDATORY sight-threatening screen — this is the core safety layer. Significant deep pain, true photophobia, reduced visual acuity, ciliary/limbal flush, corneal opacity/infiltrate, fixed/irregular pupil, hard globe + haloes, or hyperacute copious purulent discharge → this is NOT simple conjunctivitis. Route OUT by engine_id: ophtho.acute-red-eye.core.v1 (triage), ophtho.keratitis.core.v1, ophtho.uveitis.core.v1, ophtho.acute-angle-closure-glaucoma.core.v1 (protocol.angle_closure). Gonococcal/contact-lens/neonatal fire same-day ophthalmology.
   inputs: ocular_pain_severity, photophobia, visual_acuity_change, ciliary_flush_or_corneal_opacity, hyperacute_copious_purulent_discharge, contact_lens_use
   actions: workup.acute_red_eye, workup.acute_vision_loss, protocol.angle_closure
   advance: sight-threatening red flags screened and routed by engine_id if positive; if positive this engine does NOT manage onward
5. 5INITIAL_WORKUP
   Conjunctivitis is largely a clinical diagnosis (AAO PPP Varu 2018) — no routine culture for typical presentations (Sheikh Cochrane 2012). DO swab/culture + Gram stain + NAAT for: hyperacute purulent (gonococcal — Gram-negative intracellular diplococci), suspected chlamydial, neonatal ophthalmia, severe/refractory, contact-lens or immunocompromised. Fluorescein to detect corneal involvement / HSV dendrite (steroid-avoidance gate). Systemic inflammatory panels only if systemic illness/sepsis concern.
   inputs: fluorescein_corneal_staining
   actions: panel.inflammation
   advance: clinical subtype confirmed; targeted micro sent only for emergency/atypical/neonatal/contact-lens cases; corneal involvement assessed
6. 6BRANCHING_WORKUP
   Subtype decision tree: hyperacute purulent + Gram-negative diplococci → gonococcal (systemic ceftriaxone + ophthalmology emergency, exclude keratitis); chronic follicular + sexually active / neonate day 5-14 → chlamydial (systemic azithromycin/doxycycline + partner Rx + STI workup); watery + follicular + preauricular node + sick contact → adenoviral/EKC (supportive + strict infection control, watch SEIs); bilateral itch + chemosis + atopy → allergic (antihistamine/mast-cell stabilizer); mucopurulent + glued lids, no red flags → non-gonococcal bacterial (delayed/short topical antibiotic or supportive). Contact-lens or fluorescein-positive → route to ophtho.keratitis.core.v1.
   inputs: discharge_character, fluorescein_corneal_staining
   actions: workup.acute_red_eye
   advance: single conjunctivitis subtype assigned OR routed OUT to keratitis/uveitis/angle-closure by engine_id
7. 7DIFFERENTIAL
   Terminal differential with pivot findings — within conjunctivitis: bacterial (glued lids + mucopurulent + no itch pivot — Rietveld BMJ 2004) vs viral/adenoviral (watery + preauricular node + fellow-eye spread + sick contact pivot) vs gonococcal (hyperacute copious purulent + rapid corneal threat pivot) vs chlamydial (chronic follicular + STI/neonate pivot) vs allergic (itch + bilateral + chemosis + seasonality pivot). Against look-alikes: keratitis (pain + photophobia + fluorescein staining + contact-lens pivot → route OUT), anterior uveitis (ciliary flush + photophobia + cells/flare + miotic pupil pivot → route OUT), acute angle-closure glaucoma (severe pain + haloes + fixed mid-dilated pupil + hard globe pivot → protocol.angle_closure / route OUT), scleritis (deep boring pain + violaceous non-blanching scleral injection pivot → route OUT).
   advance: single best conjunctivitis subtype selected, or sight-threatening alternative assigned + routed by engine_id
8. 8RISK_STRATIFICATION
   Stratify by sight-threat and contagion: LOW (typical viral/allergic/non-gonococcal bacterial, no red flag) → supportive/stewardship outpatient; HIGH-CONTAGION (adenoviral/EKC, esp. institutional exposure) → infection-control escalation; EMERGENCY (gonococcal-hyperacute, contact-lens keratitis suspicion, neonatal ophthalmia, herpetic) → same-day/urgent ophthalmology + systemic Rx. Systemic-toxicity overlay (neonatal sepsis, disseminated gonococcal) → qSOFA/SIRS screen.
   inputs: hyperacute_copious_purulent_discharge, contact_lens_use
   actions: calc.qsofa, calc.sirs
   advance: sight-threat + contagion tier assigned; emergency tier triggers ophthalmology + systemic pathway
9. 9TREATMENT
   Subtype-stratified, stewardship-first: (1) VIRAL/adenoviral → supportive (cool compress, lubricants, hygiene), NO antibiotic, strict infection control; (2) NON-GONOCOCCAL BACTERIAL → most self-limited (Sheikh Cochrane 2012 — 41% placebo resolved by d6-10); delayed or short topical antibiotic shortens symptom duration (Everitt BMJ 2006); (3) GONOCOCCAL → systemic ceftriaxone 1 g IM single dose + saline lavage + EMERGENCY ophthalmology (corneal-perforation risk) + treat for chlamydia + STI/partner workup (CDC STI 2021); (4) CHLAMYDIAL → systemic azithromycin or doxycycline + partner Rx + STI workup (CDC STI 2021); (5) ALLERGIC → allergen avoidance + topical antihistamine/mast-cell stabilizer (olopatadine/ketotifen) ± short topical steroid ONLY with ophthalmology (HSV/IOP/cataract risk); (6) contact-lens → discontinue lens, NEVER patch, route to ophtho.keratitis.core.v1. Antibiotic-safety gating: pregnancy/pediatric → azithromycin not doxycycline for chlamydia; avoid steroids if HSV dendrite or undifferentiated.
   inputs: discharge_character, pregnancy, contact_lens_use
   advance: subtype-appropriate plan started; antibiotics withheld/delayed for typical infective; emergency cases on systemic Rx + ophthalmology
10. 10DISPOSITION
    LOW-risk typical conjunctivitis → discharge with self-care, return precautions, work/school guidance; HIGH-contagion adenoviral/EKC → discharge with strict isolation/hygiene + outbreak control (notify institution); EMERGENCY (gonococcal, contact-lens keratitis, neonatal ophthalmia, herpetic, any red flag) → same-day ophthalmology / admit and route OUT by engine_id (ophtho.acute-red-eye / keratitis / uveitis / angle-closure). Neonatal gonococcal ophthalmia → admit, IV ceftriaxone, pediatrics.
    inputs: hyperacute_copious_purulent_discharge, visual_acuity_change
    advance: disposition documented; emergency/neonatal cases escalated and routed; contagion control communicated
11. 11MONITORING
    Typical infective conjunctivitis: expect improvement within 5-7 d (Sheikh Cochrane 2012 — 65% placebo improved by d2-5 in earlier edition); if NOT improving or worsening at 48-72 h reassess for wrong subtype, red flag, or look-alike (keratitis/uveitis) and re-screen — do not silently continue. Adenoviral/EKC: watch for subepithelial infiltrates / pseudomembrane / vision drop (Liu Cochrane 2022) → ophthalmology. Gonococcal: daily corneal exam until clear (perforation risk). Allergic: reassess steroid course IOP/HSV if used.
    inputs: visual_acuity_change, ciliary_flush_or_corneal_opacity
    actions: workup.acute_vision_loss
    advance: objective improvement by 5-7 d OR re-evaluation/route-out triggered for non-response or new red flag
12. 12FOLLOWUP
    Stewardship + contagion + chronicity: counsel natural history and antibiotic-stewardship rationale (Everitt BMJ 2006 — immediate prescribing increases re-attendance and antibiotic belief); hygiene/return-to-activity guidance (adenoviral sheds ~10-14 d); ensure gonococcal/chlamydial partner treatment + STI follow-up + reporting; recurrent/chronic or treatment-refractory conjunctivitis → ophthalmology (chronic chlamydial, atopic/vernal keratoconjunctivitis, mucous membrane pemphigoid, or ocular surface malignancy mimic — AAO PPP Varu 2018); vernal/atopic → long-term ophthalmology (cyclosporine 0.1% per updated PPP).
    inputs: sexual_history_or_genital_symptoms
    advance: natural-history + hygiene counselling done; STI partner/follow-up arranged; chronic/refractory referred to ophthalmology