Merge patient information

MRG carries the prior patient identifiers, account numbers, visit numbers, and names needed when merging duplicate records or transferring a patient to a new account. It appears in ADT merge and move messages alongside PID to indicate which prior identifiers are being retired.

Create an MRG segment and read its fields directly:

from zato.hl7v2.v2_9 import MRG, CX, XPN

mrg = MRG()
mrg.prior_patient_identifier_list = CX(
    id_number='12345',
    assigning_authority='WELLNESS'
)
mrg.prior_patient_name = XPN(
    family_name='SMITH', given_name='JOHN')
mrg.prior_patient_account_number = CX(
    id_number='98765')

prior_id = mrg.prior_patient_identifier_list
prior_name = mrg.prior_patient_name
prior_acct = mrg.prior_patient_account_number

Positions 2 (prior alternate patient ID) and 4 (prior patient ID) were withdrawn in HL7 v2.9. The fields are retained as gaps to preserve the positional numbering of all subsequent fields. This is standard HL7v2 practice for deprecated fields.

The prior_patient_identifier_list field uses the CX (extended composite ID) datatype:

from zato.hl7v2.v2_9 import MRG, CX

mrg = MRG()
mrg.prior_patient_identifier_list = CX(
    id_number='12345',
    assigning_authority='WELLNESS'
)

The prior_patient_name field uses the XPN (extended person name) datatype:

from zato.hl7v2.v2_9 import MRG, XPN

mrg = MRG()
mrg.prior_patient_name = XPN(
    family_name='SMITH',
    given_name='JOHN',
    middle_name='A'
)

Zato connects to any system that speaks HL7v2 over MLLP or FHIR over REST. This includes Epic, Cerner, Meditech, Allscripts, and other EHR platforms.

Yes, Zato has built-in MLLP support for sending and receiving HL7v2 messages. MLLP channels handle the framing protocol automatically.

Zato supports HL7 v2.9, which is backward compatible with earlier versions including v2.3, v2.5, and v2.7. Standard segments and datatypes are available as typed Python classes.

Yes. Zato handles both HL7v2 and FHIR natively, so you can parse v2 messages and build FHIR resources with IG-specific extensions in the same service. Typed Python classes are available for both protocols, including extensions from US Core, UK Core, Da Vinci, and other Implementation Guides.