12-phase flow (12)

1. 1FRAME
   Frame three management arcs: (1) Hymenoptera sting reactions stratified local / large local / cutaneous systemic / systemic anaphylaxis with VIT for systemic reactors; (2) alpha-gal syndrome (delayed mammalian-meat anaphylaxis via Lone Star tick exposure); (3) non-Hymenoptera bite hypersensitivity (Skeeter syndrome, papular urticaria) for symptomatic management. Acute reactions route to allergy.anaphylaxis.v1.
   advance: Three-arc framing set; mastocytosis modifier and ACEi/beta-blocker comorbidity noted
2. 2ENTRY
   Recognise the reaction grade (local / large local / cutaneous systemic / systemic anaphylaxis) and the suspected culprit. For delayed (3-6h) post-meat reactions, screen for alpha-gal syndrome and Lone Star tick exposure history.
   inputs: reaction_grade_classification, sting_culprit_species_identification
   actions: workup.anaphylaxis
   advance: Reaction grade assigned; culprit identified; alpha-gal screening triggered if delayed-post-meat
3. 3CONTEXT
   Establish occupational/recreational re-sting probability (beekeepers, farmers, foresters, military), atopic comorbidities, asthma control (a contraindication-relative for VIT initiation), prior sting history grade, and concomitant beta-blocker or ACE inhibitor.
   inputs: occupational_or_recreational_exposure_risk, beta_blocker_ace_inhibitor_use
   advance: Re-exposure risk + asthma + meds context established
4. 4RED_FLAGS
   Active systemic reaction in progress -> route to allergy.anaphylaxis.v1 for IM epinephrine. Elevated baseline tryptase / known mastocytosis -> route to allergy.mast-cell-activation-syndrome.core.v1 for parallel evaluation and lifelong-VIT planning. Severe asthma uncontrolled -> optimise BEFORE initiating VIT.
   inputs: baseline_serum_tryptase
   actions: workup.anaphylaxis
   advance: Active anaphylaxis routed; mastocytosis arm activated; asthma control verified
5. 5INITIAL_WORKUP
   For systemic reactors and large local reactors considered for VIT: venom-specific IgE + skin testing performed >=2-4 wk after the event (refractory period), tested against bee + vespid panel + fire ant where geographically relevant. Baseline tryptase. For suspected alpha-gal: alpha-gal-specific IgE (Wilson 2019 PMID 30940532). CBC for cytopenia screening (clonal MC red flag).
   inputs: venom_specific_ige_skin_test_or_sige, alpha_gal_specific_ige, baseline_serum_tryptase
   actions: panel.cbc
   advance: sIgE / SPT panel collected; tryptase obtained; alpha-gal sIgE if suspected
6. 6BRANCHING_WORKUP
   sIgE / SPT panel guides VIT venom selection; persistent symptoms / elevated tryptase route to MCAS engine; alpha-gal-positive routes to mammalian-meat avoidance + auto-injector + counselling on concomitant gelatin / dairy (case-by-case based on individual sensitivity).
   advance: VIT venom selected; mastocytosis arm running in parallel if applicable; alpha-gal management initiated if applicable
7. 7DIFFERENTIAL
   Terminal: Hymenoptera systemic vs (alpha-gal-delayed-meat-anaphylaxis vs cardiogenic/arrhythmia mimic vs scombroid (histamine in spoiled fish, not allergy) vs vasovagal vs panic). Reaction GRADE differential (local, large local, cutaneous systemic, systemic anaphylaxis) is the primary axis driving therapy.
   advance: Single best diagnosis + grade assigned
8. 8RISK_STRATIFICATION
   Severity tier (JTF 2016 / EAACI 2018): (a) Local — no chronic Rx, no VIT. (b) Large local — H1 + topical/short oral steroid; auto-injector NOT routinely required; VIT NOT routinely indicated. (c) Cutaneous systemic in ADULTS — H1 + auto-injector consideration + adult VIT optional / improves QoL; CHILDREN — auto-injector counselling, NO VIT. (d) Systemic anaphylaxis — IM epinephrine + ED + REFER FOR VIT. (e) Mastocytosis / elevated tryptase / near-fatal reaction / occupational exposure -> LIFELONG VIT.
   inputs: age, occupational_or_recreational_exposure_risk, baseline_serum_tryptase
   advance: Severity tier assigned; VIT eligibility + duration framed
9. 9TREATMENT
   Reaction-grade-specific (JTF 2016 PMID 28007086; EAACI 2018 PMID 28748641): (1) Local — ice + analgesia; (2) Large local — H1 + topical or short oral steroid + ice; (3) Cutaneous systemic — H1 + auto-injector + adult VIT consideration; (4) Systemic anaphylaxis — IM epinephrine + ED rescue + auto-injector x 2 + REFER FOR VIT (3-5 y standard; LIFELONG if mastocytosis / elevated tryptase / near-fatal / high re-exposure risk). Alpha-gal — strict mammalian-meat avoidance + auto-injector; consider concomitant gelatin/dairy avoidance individualised. Tick-bite prevention (DEET, permethrin clothing, tick-check) reduces alpha-gal sensitisation reinforcement.
   inputs: epinephrine_auto_injector_status, age, baseline_serum_tryptase, occupational_or_recreational_exposure_risk
   advance: Grade-appropriate Rx + auto-injector + VIT plan in place
10. 10DISPOSITION
    Local / large local — outpatient with primary care; cutaneous systemic and systemic — allergist referral; active systemic reaction -> ED. VIT initiation/uptitration in allergist office with epinephrine immediately available + 30 min post-injection observation.
    advance: Outpatient allergy follow-up + ED routing of active events
11. 11MONITORING
    During VIT — symptom diary, post-injection observation 30 min, watch for systemic reaction during uptitration. Periodic baseline tryptase if mastocytosis suspected. Annual auto-injector check (carry + expiry + technique). For alpha-gal — sIgE level trend over years may decline if tick exposure ceases (some patients tolerate re-introduction with allergist supervision).
    advance: VIT surveillance + auto-injector check + tryptase trend on schedule
12. 12FOLLOWUP
    Lifelong: trigger avoidance education (Hymenoptera identification + avoidance + tick-bite prevention), auto-injector carry + technique + expiry monitoring. VIT 3-5 y standard, then reassess sting tolerance + tryptase + risk factors; LIFELONG VIT for high-risk groups. Alpha-gal — periodic re-evaluation of sIgE trend; supervised reintroduction discussion only after years of declining titres.
    inputs: epinephrine_auto_injector_status
    advance: Lifelong plan reviewed; VIT continuation/discontinuation decision documented