Infherno: End-to-end Agent-based FHIR Resource Synthesis from Free-form Clinical Notes

Johann Frei, Nils Feldhus, Lisa Raithel, Roland Roller, Alexander Meyer, Frank Kramer


Abstract
For clinical data integration and healthcare services, the HL7 FHIR standard has established itself as a desirable format for interoperability between complex health data. Previous attempts at automating the translation from free-form clinical notes into structured FHIR resources address narrowly defined tasks and rely on modular approaches or LLMs with instruction tuning and constrained decoding. As those solutions frequently suffer from limited generalizability and structural inconformity, we propose an end-to-end framework powered by LLM agents, code execution, and healthcare terminology database tools to address these issues. Our solution, called Infherno, is designed to adhere to the FHIR document schema and competes well with a human baseline in predicting FHIR resources from unstructured text. The implementation features a front end for custom and synthetic data and both local and proprietary models, supporting clinical data integration processes and interoperability across institutions. Gemini 2.5-Pro excels in our evaluation on synthetic and clinical datasets, yet ambiguity and feasibility of collecting ground-truth data remain open problems.
Anthology ID:
2026.eacl-demo.13
Volume:
Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 3: System Demonstrations)
Month:
March
Year:
2026
Address:
Rabat, Marocco
Editors:
Danilo Croce, Jochen Leidner, Nafise Sadat Moosavi
Venue:
EACL
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
163–174
Language:
URL:
https://preview.aclanthology.org/ingest-eacl/2026.eacl-demo.13/
DOI:
Bibkey:
Cite (ACL):
Johann Frei, Nils Feldhus, Lisa Raithel, Roland Roller, Alexander Meyer, and Frank Kramer. 2026. Infherno: End-to-end Agent-based FHIR Resource Synthesis from Free-form Clinical Notes. In Proceedings of the 19th Conference of the European Chapter of the Association for Computational Linguistics (Volume 3: System Demonstrations), pages 163–174, Rabat, Marocco. Association for Computational Linguistics.
Cite (Informal):
Infherno: End-to-end Agent-based FHIR Resource Synthesis from Free-form Clinical Notes (Frei et al., EACL 2026)
Copy Citation:
PDF:
https://preview.aclanthology.org/ingest-eacl/2026.eacl-demo.13.pdf