Huli FHIR Core Implementation Guide (R4)
0.1.0 - Release

Huli FHIR Core Implementation Guide (R4) - Local Development build (v0.1.0) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

Extension: Huli Second Lastname

Official URL: https://fhir.huli.ai/r4/StructureDefinition/second-lastname Version: 0.1.0
Active as of 2026-09-11 Computable Name: HuliSecondLastname

The patient's second family name, following multi-surname naming conventions (LATAM, Iberian, Filipino, etc.). Placed on HumanName to preserve the boundary between the primary surname (HumanName.family) and the secondary one.

In Mexico, this maps to the apellido materno required by CURP and official documents; in Chile, to the segundo apellido. The extension is neutral about lineage — different cultures fill it from either parent.

Context of Use

    This extension may be used on the following element(s)

Usage info

Usages:

You can also check for usages in the FHIR IG Statistics

Formal Views of Extension Content

Description of Profiles, Differentials, Snapshots, and how the XML and JSON presentations work.

This structure is derived from Extension

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. Extension 0..* Extension Huli Second Lastname
... extension 0..0 Extension
... url 1..1 uri "https://fhir.huli.ai/r4/StructureDefinition/second-lastname"
... value[x] 1..1 string Value of extension

doco Documentation for this format
NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. Extension 0..* Extension Huli Second Lastname
... id 0..1 string Unique id for inter-element referencing
... extension 0..0 Extension
Slice: Unordered, Open by value:url
... url 1..1 uri "https://fhir.huli.ai/r4/StructureDefinition/second-lastname"

doco Documentation for this format

This structure is derived from Extension

Summary

Simple Extension with the type string: The patient's second family name, following multi-surname naming conventions (LATAM, Iberian, Filipino, etc.). Placed on HumanName to preserve the boundary between the primary surname (HumanName.family) and the secondary one.

In Mexico, this maps to the apellido materno required by CURP and official documents; in Chile, to the segundo apellido. The extension is neutral about lineage — different cultures fill it from either parent.

Differential View

This structure is derived from Extension

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. Extension 0..* Extension Huli Second Lastname
... extension 0..0 Extension
... url 1..1 uri "https://fhir.huli.ai/r4/StructureDefinition/second-lastname"
... value[x] 1..1 string Value of extension

doco Documentation for this format

Snapshot View

NameFlagsCard.TypeDescription & Constraints    Filter: Filtersdoco
.. Extension 0..* Extension Huli Second Lastname
... id 0..1 string Unique id for inter-element referencing
... extension 0..0 Extension
Slice: Unordered, Open by value:url
... url 1..1 uri "https://fhir.huli.ai/r4/StructureDefinition/second-lastname"

doco Documentation for this format

This structure is derived from Extension

Summary

Simple Extension with the type string: The patient's second family name, following multi-surname naming conventions (LATAM, Iberian, Filipino, etc.). Placed on HumanName to preserve the boundary between the primary surname (HumanName.family) and the secondary one.

In Mexico, this maps to the apellido materno required by CURP and official documents; in Chile, to the segundo apellido. The extension is neutral about lineage — different cultures fill it from either parent.

 

Other representations of profile: CSV, Excel, Schematron

Constraints

Id Grade Path(s) Description Expression
ele-1 error **ALL** elements All FHIR elements must have a @value or children hasValue() or (children().count() > id.count())
ext-1 error **ALL** extensions Must have either extensions or value[x], not both extension.exists() != value.exists()