AllergyIntolerance¶

Overview¶

The AllergyIntolerance resource records a patient's allergies and intolerances to substances. This is a critical safety resource that captures information about adverse reactions that may occur upon exposure to specific substances, enabling clinical decision support and preventing harmful exposures.

FHIR R4 Specification¶

See the official HL7 specification: https://hl7.org/fhir/R4/allergyintolerance.html

Supported Fields¶

Field	Type	Description
`id`	string	Logical ID of the resource
`meta`	Meta	Resource metadata including versionId and lastUpdated
`clinicalStatus`	CodeableConcept	active, inactive, resolved
`verificationStatus`	CodeableConcept	unconfirmed, presumed, confirmed, refuted, entered-in-error
`type`	code	allergy or intolerance
`category`	code[]	food, medication, environment, biologic
`criticality`	code	low, high, unable-to-assess
`code`	CodeableConcept	The allergen (SNOMED CT code)
`patient`	Reference(Patient)	Patient who has the allergy
`encounter`	Reference(Encounter)	Encounter when recorded
`onsetDateTime`	dateTime	When allergy was first identified
`recordedDate`	dateTime	When recorded in the system
`recorder`	Reference(Practitioner)	Who recorded the allergy
`asserter`	Reference(Patient\|Practitioner)	Source of the information
`reaction`	BackboneElement[]	Reaction manifestations and severity
`note`	Annotation[]	Additional clinical notes

Search Parameters¶

Parameter	Type	Description	Example
`_id`	token	Resource ID	`_id=abc123`
`patient`	reference	Patient reference	`patient=Patient/123`
`code`	token	Allergen code	`code=http://snomed.info/sct\\|91936005`
`clinical-status`	token	Clinical status	`clinical-status=active`
`verification-status`	token	Verification status	`verification-status=confirmed`
`category`	token	Category	`category=medication`
`criticality`	token	Criticality level	`criticality=high`
`type`	token	Type	`type=allergy`
`onset`	date	Onset date	`onset=ge2020-01-01`
`date`	date	Recorded date	`date=2024-06-15`
`recorder`	reference	Recorder reference	`recorder=Practitioner/456`
`asserter`	reference	Asserter reference	`asserter=Patient/123`

Examples¶

Create an AllergyIntolerance¶

curl -X POST http://localhost:8080/baseR4/AllergyIntolerance \
  -H "Content-Type: application/fhir+json" \
  -d '{
    "resourceType": "AllergyIntolerance",
    "clinicalStatus": {
      "coding": [{
        "system": "http://terminology.hl7.org/CodeSystem/allergyintolerance-clinical",
        "code": "active",
        "display": "Active"
      }]
    },
    "verificationStatus": {
      "coding": [{
        "system": "http://terminology.hl7.org/CodeSystem/allergyintolerance-verification",
        "code": "confirmed",
        "display": "Confirmed"
      }]
    },
    "type": "allergy",
    "category": ["medication"],
    "criticality": "high",
    "code": {
      "coding": [{
        "system": "http://snomed.info/sct",
        "code": "91936005",
        "display": "Penicillin allergy"
      }],
      "text": "Penicillin allergy"
    },
    "patient": {"reference": "Patient/patient-001"},
    "onsetDateTime": "2015-03-01",
    "recordedDate": "2024-06-15T10:30:00Z",
    "reaction": [{
      "manifestation": [{
        "coding": [{
          "system": "http://snomed.info/sct",
          "code": "39579001",
          "display": "Anaphylaxis"
        }]
      }],
      "severity": "severe"
    }],
    "note": [{
      "text": "Patient has history of anaphylactic reaction to penicillin. Epinephrine auto-injector prescribed."
    }]
  }'

Search AllergyIntolerances¶

# By patient
curl "http://localhost:8080/baseR4/AllergyIntolerance?patient=Patient/123"

# By category (medication allergies)
curl "http://localhost:8080/baseR4/AllergyIntolerance?category=medication"

# By criticality (high-risk allergies)
curl "http://localhost:8080/baseR4/AllergyIntolerance?criticality=high"

# Active allergies only
curl "http://localhost:8080/baseR4/AllergyIntolerance?clinical-status=active"

# Confirmed medication allergies
curl "http://localhost:8080/baseR4/AllergyIntolerance?category=medication&verification-status=confirmed"

# Combined: patient's active high-criticality allergies
curl "http://localhost:8080/baseR4/AllergyIntolerance?patient=Patient/123&clinical-status=active&criticality=high"

With _include¶

# Include the patient
curl "http://localhost:8080/baseR4/AllergyIntolerance?patient=123&_include=AllergyIntolerance:patient"

# Include the recorder
curl "http://localhost:8080/baseR4/AllergyIntolerance?_include=AllergyIntolerance:recorder"

Patient Compartment Search¶

# Get all allergies for a patient via compartment
curl "http://localhost:8080/baseR4/Patient/123/AllergyIntolerance"

# With criticality filter
curl "http://localhost:8080/baseR4/Patient/123/AllergyIntolerance?criticality=high"

Generator¶

The AllergyIntoleranceGenerator creates synthetic AllergyIntolerance resources with:

Realistic SNOMED CT allergen codes for medications, foods, and environmental allergens
Weighted category distribution (40% medication, 35% food, 25% environment)
Appropriate criticality levels with associated reactions
SNOMED CT reaction manifestation codes with severity
Clinical notes for high-criticality allergies

Usage¶

from fhirkit.server.generator import AllergyIntoleranceGenerator

generator = AllergyIntoleranceGenerator(seed=42)

# Generate a random allergy
allergy = generator.generate(
    patient_ref="Patient/123",
    recorder_ref="Practitioner/456"
)

# Generate specific category
med_allergy = generator.generate_medication_allergy(
    patient_ref="Patient/123"
)

food_allergy = generator.generate_food_allergy(
    patient_ref="Patient/123"
)

env_allergy = generator.generate_environmental_allergy(
    patient_ref="Patient/123"
)

# Generate batch
allergies = generator.generate_batch(
    count=5,
    patient_ref="Patient/123"
)

Clinical Codes¶

Loaded from fixtures/allergy_codes.json:

Medication Allergens (SNOMED CT)¶

Code	Display
91936005	Penicillin allergy
294505008	Amoxicillin allergy
294532003	Sulfonamide allergy
293586001	Aspirin allergy
294306009	Ibuprofen allergy

Food Allergens (SNOMED CT)¶

Code	Display
91935009	Allergy to peanuts
91934008	Allergy to tree nuts
91930004	Allergy to eggs
91932007	Allergy to shellfish
91937001	Allergy to soy
425525006	Allergy to dairy products

Environmental Allergens (SNOMED CT)¶

Code	Display
418689008	Allergy to grass pollen
419474003	Allergy to tree pollen
232350006	House dust mite allergy
232346004	Cat dander allergy
441634002	Allergy to latex

Reaction Manifestations (SNOMED CT)¶

Code	Display	Typical Severity
39579001	Anaphylaxis	severe
271807003	Skin rash	mild
126485001	Urticaria	mild
267036007	Dyspnea	moderate
271757001	Facial swelling	severe
418363000	Throat tightness	severe

Clinical Status Codes¶

Code	Display
active	Active
inactive	Inactive
resolved	Resolved

Criticality Levels¶

Code	Description
low	Low risk of life-threatening reaction
high	High risk of life-threatening reaction
unable-to-assess	Unable to assess criticality