Cross-Border Patient Data Exchange in Europe: Architecture, Standards, and Real-World Challenges

Separate the exchange service from the access decision

MyHealth@EU supports cross-border patient summaries and ePrescriptions/eDispensations, with availability depending on participating countries and services. Check the Commission’s cross-border health-service information before promising a particular exchange route.

Consider a traveller whose treating clinician requests a patient summary: verify identity and access first, request the supported document through the approved national connection, preserve its source and timestamp, and distinguish an unavailable response from an empty clinical history. Terminology translation must not silently change clinical meaning.

Use the patient identity guide for matching risks and the GDPR rights guide for governance workflows.

Introduction

Every year, millions of Europeans travel across borders for work, tourism, or healthcare. When a German tourist has a medical emergency in Portugal, or a French worker needs a prescription filled in Belgium, the treating clinician needs access to the patient's health data — allergies, medications, chronic conditions — to provide safe care.

This is the problem MyHealth@EU solves. It is the operational cross-border health data exchange infrastructure that has been running since 2019 and is expanding rapidly under the EHDS regulation. As someone who builds healthcare interoperability systems, I find the MyHealth@EU architecture to be one of the most technically interesting — and challenging — integration problems in European healthcare.

What MyHealth@EU Exchanges Today

MyHealth@EU currently supports two cross-border services:

Patient Summary (PS)

A structured document containing the essential clinical information a clinician needs in an unplanned care encounter:

• Active diagnoses and medical problems
• Current medications
• Allergies and adverse reactions
• Surgical procedures history
• Medical devices and implants
• Vaccination history

The Patient Summary follows the European Patient Summary (EPS) specification, which is closely aligned with the HL7 International Patient Summary (IPS) standard.

ePrescription / eDispensation

Enables patients to fill prescriptions issued in their home country at pharmacies in another EU member state:

1. A doctor in Country A issues an electronic prescription
2. The patient visits a pharmacy in Country B
3. The pharmacist queries MyHealth@EU to retrieve the prescription
4. The medication is dispensed and a dispensation record is sent back to Country A

The Technical Architecture

MyHealth@EU uses a federated peer-to-peer architecture where each participating country operates a National Contact Point for eHealth (NCPeH):

Country of Affiliation (A)          Country of Treatment (B)
(Patient's home country)            (Where patient seeks care)

┌─────────────────────┐            ┌─────────────────────┐
│   National Health    │            │   Point of Care     │
│   Infrastructure    │            │   (Hospital/Pharmacy)│
│   (EHR Systems)     │            │                     │
└─────────┬───────────┘            └─────────┬───────────┘
          │                                  │
          ▼                                  ▼
┌─────────────────────┐            ┌─────────────────────┐
│     NCPeH-A         │            │     NCPeH-B         │
│  ┌───────────────┐  │            │  ┌───────────────┐  │
│  │  Translation  │  │            │  │  Translation  │  │
│  │  Service      │  │            │  │  Service      │  │
│  ├───────────────┤  │  eHDSI     │  ├───────────────┤  │
│  │  Security     │  │◄──────────►│  │  Security     │  │
│  │  Gateway      │  │  (TLS +    │  │  Gateway      │  │
│  ├───────────────┤  │  eIDAS)    │  ├───────────────┤  │
│  │  Document     │  │            │  │  Document     │  │
│  │  Transform    │  │            │  │  Transform    │  │
│  └───────────────┘  │            │  └───────────────┘  │
└─────────────────────┘            └─────────────────────┘

The Exchange Flow

When a clinician in Country B needs a patient summary from Country A:

1. Patient identification — the patient is identified using their national health insurance card or European Health Insurance Card (EHIC)
2. NCPeH-B queries NCPeH-A — a cross-border query is sent through the eHDSI infrastructure using IHE XCA (Cross-Community Access) profiles
3. NCPeH-A retrieves the patient summary from the national health infrastructure
4. Translation and transformation — the document is translated from the national format to the European exchange format, and clinical terms are transcoded to international terminologies
5. NCPeH-B receives and renders — the clinician sees the patient summary in their local language

Standards Under the Hood

The eHDSI (eHealth Digital Service Infrastructure) uses a combination of standards:

The Real-World Challenges

1. Terminology Translation

This is arguably the hardest problem in cross-border health data exchange. Each country uses different coding systems for medications, diagnoses, and procedures:

• Medications — Germany uses PZN (Pharmazentralnummer), France uses CIP codes, Switzerland uses GTIN. All must be mapped to ATC (Anatomical Therapeutic Chemical) classification for cross-border exchange.
• Diagnoses — most countries use ICD-10, but with national extensions (ICD-10-GM in Germany, ICD-10-FR in France). SNOMED CT adoption varies significantly.
• Procedures — no common European procedure coding system exists. SNOMED CT procedure codes are the target, but national systems (OPS in Germany, CCAM in France) still dominate.

Automated terminology mapping works for straightforward cases, but edge cases require manual curation. I have seen medications that exist in one country but have no equivalent in another — a situation that cannot be fully resolved technically.

2. Data Quality and Completeness

The quality of cross-border patient summaries depends entirely on the quality of the source data. If a patient's home country EHR has incomplete medication lists or uncoded diagnoses, the cross-border summary will reflect those gaps.

Common data quality issues I have encountered:

• Free-text only diagnoses that cannot be coded to SNOMED CT or ICD-10
• Incomplete medication records where over-the-counter medications are missing
• Outdated information from systems that do not regularly update patient summaries
• Missing allergy data — the distinction between "no known allergies" and "allergy status not recorded" is critical and often lost

3. Language and Localization

Clinical documents must be human-readable in the language of the treating clinician. This requires:

• Coded term translation — SNOMED CT and ICD-10 have multilingual descriptions, but coverage is inconsistent
• Free-text translation — clinical notes in free text require medical-grade translation, which is not always available
• Cultural context — medication brand names, dosage conventions, and clinical practices vary by country

4. Patient Consent and Identification

Each country has different consent models for health data sharing:

• Some countries require explicit opt-in consent for cross-border sharing
• Others allow sharing under the assumption of implied consent for treatment purposes
• The EHDS will harmonize this, but the transition period creates legal complexity

Patient identification across borders remains challenging. The European Health Insurance Card (EHIC) provides a starting point, but matching EHIC data to national health records is not always straightforward — name transliterations, date format differences, and missing data can all cause matching failures.

5. Infrastructure Reliability

Cross-border exchanges depend on the availability of both countries' NCPeH infrastructure. In practice:

• Downtime windows differ by country — a query sent during one country's maintenance window will fail
• Response times vary significantly — some countries return patient summaries in seconds, others take minutes
• Error handling must account for partial failures — one country's NCPeH being unavailable should not block access to data from other countries

Where It Is Heading

Expansion Under EHDS

The Commission’s EHDS implementation timeline distinguishes the first priority exchange group in March 2029 from medical images, laboratory results and discharge reports in March 2031. These are phased application milestones, not evidence that every exchange is available today.

FHIR Migration

FHIR and the International Patient Summary are useful design references. Confirm the document format, profile version and validation rules required by the actual national service; do not assume a universal FHIR replacement for existing CDA exchanges.

The European EHR Exchange Format

As discussed in my EHDS article, the Commission will define a European EHR Exchange Format that standardizes data categories, terminologies, and technical formats. This will gradually reduce the fragmentation that makes cross-border exchange so challenging today.

What Developers Should Know

If you are building systems that need to participate in cross-border health data exchange:

1. Assess the International Patient Summary (IPS) alongside the profiles required by the connected service
2. Adopt international terminologies — select SNOMED CT, LOINC, ATC and other code systems according to the exchange specification and applicable licences
3. Design for multilingual content — your system must handle clinical data in multiple languages
4. Build robust error handling — cross-border queries will fail, timeout, or return partial results. Your UI must handle these gracefully
5. Understand the consent landscape — cross-border data sharing consent requirements vary by country and are evolving under the EHDS

Conclusion

Cross-border patient data exchange in Europe is a remarkable technical achievement — and an ongoing challenge. The combination of federated architecture, terminology translation, multilingual requirements, and varying national regulations makes it one of the most complex integration problems in healthcare. But it is also one of the most impactful — enabling safe care for millions of Europeans who travel across borders.

If you are working on cross-border health data exchange or need to make your system MyHealth@EU-compatible, feel free to get in touch.