ADT^A23 — Delete a Patient Record

Patient record deletion: A23 targets test data, mistaken duplicates, or GDPR/HIPAA right-to-erasure requests. To be handled with extreme care.

Metadata

• Standard: HL7 v2.5.1
• Chapter: 3 — Patient Administration
• Message type: ADT^A23^ADT_A23
• Trigger event: A23 — Delete a Patient Record
• Acknowledgment: ACK^A23^ACK

Purpose

A23 requests permanent deletion of the identified PID. Three legitimate cases: test environment cleanup (data fixtures), duplicate created in error with no clinical data attached, regulatory deletion (GDPR article 17 — right to erasure, HIPAA PHI minimization for minors having left the system).

Segment structure

Structure ADT_A23: MSH, EVN, PID, PD1, PV1 (optional).

Real-world example

Delete test fixture MRN000TEST:

MSH|^~\&|HIS|HOSP01|EHR|CLINIC02|20260516153000||ADT^A23^ADT_A23|MSG00023001|P|2.5.1|||AL|NE
EVN|A23|20260516153000|||DRJONES^Jones^Sarah^^^DR.|TEST DATA CLEANUP
PID|1||MRN000TEST^^^HOSP^MR||TEST^FIXTURE^^^MR.||19990101|M
PV1|1|O|||||||||||||||||||TEST123|||||||||||||||||HOSP01

Acknowledgment (ACK)

MSH|^~\&|EHR|CLINIC02|HIS|HOSP01|20260516153001||ACK^A23^ACK|ACK00023001|P|2.5.1
MSA|AA|MSG00023001

Common errors

• A23 on a patient with clinical data: rejected by any compliant EHR — orphaned references violate referential integrity.
• A23 in production without audit trail: legal traceability impossible. EVN-7 (Event Occurred) and EVN-4 (Event Reason) must justify.
• A23 / A18 confusion: A23 deletes, A18 merges. The PID must NEVER be deleted after a successful merge; it becomes the surviving alias.

Related ADT events

See also: ADT^A18.