Diagnosis and procedure

DPS communicates diagnosis and procedure codes that define coverage policy rules. It specifies which diagnoses are covered, limited, excluded, or require prior authorization, along with effective date ranges. It appears in master file messages for distributing payer coverage policies.

The diagnosis_code_mcp field uses the CWE datatype with HL7 table 0051:

from zato.hl7v2.v2_9 import DPS, CWE

dps = DPS()
dps.diagnosis_code_mcp = CWE(
    identifier='J18.9',
    text='Pneumonia unspecified',
    name_of_coding_system='ICD10'
)

The type_of_limitation field uses the CNE datatype with HL7 table 0940:

from zato.hl7v2.v2_9 import DPS, CNE

dps = DPS()
dps.type_of_limitation = CNE(
    identifier='LIM',
    text='Limited coverage',
    name_of_coding_system='HL70940'
)

Field 2 is not defined in the DPS segment specification. The segment jumps from position 1 (diagnosis code) directly to position 3 (effective date/time). This is an intentional gap in the HL7v2 standard.

Use the effective_date_time and expiration_date_time fields to define the coverage window:

from zato.hl7v2.v2_9 import DPS

dps = DPS()
dps.effective_date_time = '20240101'
dps.expiration_date_time = '20241231'

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.