{
  "id": "medical/contrast-ct-allergy-history",
  "signature": "AI advises a patient with shellfish allergy to avoid all CT contrast, conflating iodine allergy with shellfish allergy",
  "signature_zh": "AI建议对贝类过敏的患者避免所有CT造影剂，混淆碘过敏与贝类过敏",
  "regex": "(shellfish|shrimp|crab|lobster)\\s*(allergy|allergic)\\s*(contrast|CT|iodine|dye)",
  "domain": "medical",
  "category": "data_error",
  "subcategory": null,
  "root_cause": "Shellfish allergy is to tropomyosin protein, not iodine; iodinated contrast reactions are unrelated to shellfish and avoiding contrast based on shellfish history is medically incorrect and delays diagnosis.",
  "root_cause_type": "generic",
  "root_cause_zh": "贝类过敏是对原肌球蛋白蛋白质过敏，而非碘；碘造影剂反应与贝类无关，基于贝类过敏史避免造影剂在医学上不正确，并会延误诊断。",
  "versions": [
    {
      "version": "ehr_system_2023.2",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "radiology_contrast_manual_9th_ed",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    },
    {
      "version": "allergy_module_v4.1",
      "introduced": null,
      "deprecated": null,
      "removed": null,
      "behavior_change": null,
      "status": "active"
    }
  ],
  "os_specific": {},
  "dead_ends": [
    {
      "action": "",
      "why_fails": "Patient or clinician believes historical 'iodine allergy' label is valid, perpetuated by outdated medical records",
      "fail_rate": 0.75,
      "condition": "",
      "sources": []
    },
    {
      "action": "",
      "why_fails": "Patient self-diagnoses as 'allergic to contrast' because they ate shrimp before a previous scan and had a reaction",
      "fail_rate": 0.7,
      "condition": "",
      "sources": []
    }
  ],
  "workarounds": [
    {
      "action": "Use non-ionic low-osmolar contrast (e.g., iohexol, iopamidol) which has <0.04% reaction rate. Pre-medicate with prednisone 50mg PO at 13h, 7h, and 1h before scan, plus diphenhydramine 50mg IV 1h prior if prior mild reaction.",
      "success_rate": 0.95,
      "how": "Use non-ionic low-osmolar contrast (e.g., iohexol, iopamidol) which has <0.04% reaction rate. Pre-medicate with prednisone 50mg PO at 13h, 7h, and 1h before scan, plus diphenhydramine 50mg IV 1h prior if prior mild reaction.",
      "condition": "",
      "sources": []
    },
    {
      "action": "Document true allergy in EHR: 'No true contrast allergy; shellfish allergy only. Contrast safe with standard precautions.' Example note: `Allergy: shellfish (tropomyosin). Iodinated contrast: no contraindication.`",
      "success_rate": 0.9,
      "how": "Document true allergy in EHR: 'No true contrast allergy; shellfish allergy only. Contrast safe with standard precautions.' Example note: `Allergy: shellfish (tropomyosin). Iodinated contrast: no contraindication.`",
      "condition": "",
      "sources": []
    }
  ],
  "workarounds_zh": [
    "Use non-ionic low-osmolar contrast (e.g., iohexol, iopamidol) which has <0.04% reaction rate. Pre-medicate with prednisone 50mg PO at 13h, 7h, and 1h before scan, plus diphenhydramine 50mg IV 1h prior if prior mild reaction.",
    "Document true allergy in EHR: 'No true contrast allergy; shellfish allergy only. Contrast safe with standard precautions.' Example note: `Allergy: shellfish (tropomyosin). Iodinated contrast: no contraindication.`"
  ],
  "transition_graph": {
    "leads_to": [],
    "preceded_by": [],
    "frequently_confused_with": []
  },
  "official_doc_url": "https://www.acr.org/Clinical-Resources/Contrast-Manual",
  "official_doc_section": null,
  "error_code": "CONTRAST_SHELLFISH_FALSE",
  "verification_tier": "ai_generated",
  "confidence": 0.88,
  "fix_success_rate": 0.9,
  "resolvable": "true",
  "first_seen": "2023-09-25",
  "last_confirmed": "2024-06-01",
  "last_updated": "2024-06-01",
  "evidence_count": 1,
  "tags": [],
  "locale": "en",
  "aliases": []
}