NHS North West Genomics - Local Development build (v0.1.0) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

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Overview

Diagnostic testing plays a central role in supporting clinical processes by providing objective information that guides decision-making throughout a patient’s care journey. Its use spans from initial assessment to long-term management and evaluation of outcomes.

Genomic diagnostic testing supports clinical decision making by analysing a patient’s DNA or RNA to identify genetic variations that influence disease risk, diagnosis, treatment, and prognosis. By providing highly specific, personalised information, it enhances the precision and effectiveness of clinical care.

graph TD;

    A[Assessment]-->|Creates Observations| B;
    A--> |Needs Diagnostic Testing and Completes| T;
    B[Diagnosis]-->|Creates Condition| C;
    T[<b>Order Placer</b><br/>Genomics Test Order]--> |"Sends Laboratory Order - LAB-1<br/>FHIR Message O21"| AN;
    T --> |Asks for| S
    S[Specimen Collection] --> |Sends Specimen| AN;
    AN["<b>Order Filler</b><br/>Diagnostic Testing"] --> |"Requests further tests <br/>(reflex order)"| T;
    AN --> |"Creates Laboratory Report - LAB-3<br/>HL7 v2 ORU_R01"| B;
    AN --> |Sends Laboratory Report| A;
    C[Plan]-->|Creates Goals and Tasks| D;
    D[Implement/Interventions]-->|Actions Tasks| E;
    E[Evaluate]--> |Reviews Care| A;
    
    click T Questionnaire-GenomicTestOrder.html
    click AN Questionnaire-GenomicTestReport.html
    click S ExampleScenario-BiopsyProcedure.html

    classDef purple fill:#E1D5E7;

    classDef yellow fill:#FFF2CC;
    classDef pink fill:#F8CECC
    classDef green fill:#D5E8D4;
    classDef blue fill:#DAE8FC;
    classDef orange fill:#FFE6CC;

    class A pink
    class B yellow
    class C green
    class D blue
    class E orange

    class O,S,T,AN purple

NHS North West Genomics is a new NHS service that brings together clinical diagnostic genomic testing services across the North West of England. While regionally delivered, the service supports genomic testing requests from across the UK. The service is hosted by Manchester University NHS Foundation Trust.

As part of this transition, existing electronic ordering and reporting systems will be supported by a Regional Integration Engine (RIE) and a Genomic Clinical Data Repository. These components enable interoperability between local clinical systems and regional genomic laboratory services.

Messaging

Point To Point Messaging

The diagram below illustrates point to point messaging between an Order Placer and an Order Filler. The Order Filler is typically a Laboratory Information Management System (LIMS), while the Order Placer is usually a clinical system such as an Electronic Patient Record (EPR).

Not all interactions will necessarily be electronic. For example, reports may be sent by email, and orders may be submitted via email or physically accompany the specimen.

graph LR
    OrderPlacer --> |1. General Order<br/>HL7 v2 ORM_O01| OrderFiller
    OrderFiller --> |2. Laboratory Report<br/>HL7 v2 ORU_R01| OrderPlacer  

In many NHS Trusts, a Trust Integration Engine (TIE) is used to facilitate this point-to-point messaging.

graph LR

    OrderPlacer --> |1. General Order<br/>HL7 v2 ORM_O01| TIE[Trust Integration Engine]
    TIE --> |2. General Order<br/>HL7 v2 ORM_O01| OrderFiller
    OrderFiller --> |3. Laboratory Report<br/>HL7 v2 ORU_R01| TIE
    TIE --> |4. Laboratory Report<br/>HL7 v2 ORU_R01| OrderPlacer  

TIEs typically handle transformations between the different HL7 v2 variants used by Order Placers (e.g. EPRs) and Order Fillers (e.g. LIMS).

Message Routing

The regional service may support more than 20 NHS Trusts, each using different clinical systems. Within NHS North West Genomics itself, multiple LIMS and supporting clinical systems are in use.

graph TD
    
    subgraph NHSA[NHS Trust A]
        OrderPlacer1[Order Placer] --> |General Order<br/>HL7 v2 ORM_O01| TIE1[Trust Integration Engine]
        TIE1 --> |Laboratory Report<br/>HL7 v2 ORU_R01| OrderPlacer1  
    end 
    subgraph NHSB[NHS Trust B]
        OrderPlacer2[Order Placer] --> |General Order<br/>HL7 v2 ORM_O01| TIE2[Trust Integration Engine]
        TIE2 --> |Laboratory Report<br/>HL7 v2 ORU_R01| OrderPlacer2 
    end 

    subgraph GMSA[NHS North West Genomics]
        RIE[Regional Integration Engine] --> |General Order<br/>HL7 v2 ORM_O01| OrderFiller1[Order Filler<br/>LIMS 1]
        OrderFiller1 --> |Laboratory Report<br/>HL7 v2 ORU_R01| RIE   
        RIE[Regional Integration Engine] --> |General Order<br/>HL7 v2 ORM_O01| OrderFiller2[Order Filler<br/>LIMS 2]
        OrderFiller2 --> |Laboratory Report<br/>HL7 v2 ORU_R01| RIE          
    end 
    
    TIE1 --> |Order<br/>HL7 v2 ORM_O01| RIE
    RIE --> |Laboratory Report<br/>HL7 v2 ORU_R01| TIE1 
    TIE2 --> |Order<br/>HL7 v2 ORM_O01| RIE
    RIE --> |Laboratory Report<br/>HL7 v2 ORU_R01| TIE2 

While this architecture is complex, it builds on existing interfaces. The RIE’s primary role is message distribution and routing rather than altering the underlying interaction patterns.

The Regional Integration Engine introduces message routing across the region. From a Trust perspective, interactions remain largely unchanged: reports are returned to the originating Order Placer. For example, if Alder Hey places an order, the laboratory report is returned to Alder Hey.

graph LR
    OrderPlacer[Order Placer<br/><br/>NHS Trust inc. EPR and TIE] --> |1. Laboratory Order<br/>HL7 v2 OML_O21<br/><br/><b>IHE LTW LAB-1</b>| RIE[Regional Integration Engine]
    RIE --> |4. Laboratory Report<br/>HL7 v2.5.1 ORU_R01<br/><br/><b>IHE LTW LAB-3</b>| OrderPlacer 

    subgraph GMSA[NHS North West Genomics]
        RIE --> |2. Laboratory Order<br/>HL7 v2 ORM_O01| OrderFiller
        OrderFiller --> |3. Laboratory Report<br/>HL7 v2 ORU_R01| RIE
    end

Data Contracts (Domain Entities)

This model requires coordination between NHS Trusts and regional standardisation of HL7 (v2 and FHIR). Key changes include:

• Medical Record Number (MRN): MRNs may overlap across Trusts, so they are augmented with the ODS code of the originating NHS organisation.
• Patient Identifiers: NHS Number, CHI Number, and HSNI become the primary patient identifiers. NHS Numbers must be verified against national demographic services.
• Clinical Coding: SNOMED CT and LOINC are used for OBX segments and observations. Local codes may still be included where required.
• Specimen Messaging: Specimen information must be included in orders, requiring the use of HL7 v2.5.1 OML_O21 rather than ORM_O01. This supports distributed genomic testing, where multiple tests may be performed on a single specimen across several laboratories.

Key data contracts are:

The RIE will not perform transformation of HL7 messages. Responsibility for message transformation remains with each NHS Trust’s TIE and all parties are expected to use the same Data Contracts.

Domain Archetypes

The Data Contracts are used to form Domain Archetypes which provide a high level model for both orders and reports.

The domain archetypes also provide details around SNOMED CT and LOINC codes.

Event Contracts

Finally, HL7 itself does not define workflow expectations between Order Placers and Order Fillers. These are specified in

• ​IHE Laboratory Testing Workflow (LTW) profile
• ​IHE Inter Laboratory Workflow (ILW) profile (Future)
• IHE Specimen Event Tracking (SET) profile (Future)

Genomic Data and Document Sharing

One of the main issues with messaging is that it focuses on interactions betwee two parties, the order placer and the order filler. It does not address the wider sharing of genomic data and documents between NHS Trusts, GP Practices, and many other practitioners. To rectify this a central genomic clinical data repository will be established. This will provide a FHIR RESTful (read only API). This repository is populated by data being passed via the RIE.

API Contracts

It is expected that the CDR will follow emerging IHE Europe standards for sharing clinical data and documents. At present these include:

• IHE Mobile access to Health Documents (MHD) ITI-66 and ITI-67 HL7 FHIR
• IHE Query for Existing Data for Mobile (QEDm) PCC-44 HL7 FHIR
• IHE Patient Demographics Query for Mobile (PDQm) ITI-78 HL7 FHIR
• IHE Internet User Authorization (IUA) OAuth2
• IHE Basic Audit Log Patterns (BALP) HL7 FHIR

How to Read this IG

SNOMED CT

UK edition of SNOMED (83821000000107)

Dependencies

IG	Package	FHIR	Comment
NHS North West Genomics	fhir.nwgenomics.nhs.uk#0.1.0	R4
HL7 Terminology (THO)	hl7.terminology.r4#7.0.1	R4	Automatically added as a dependency - all IGs depend on HL7 Terminology
FHIR Extensions Pack	hl7.fhir.uv.extensions.r4#5.2.0	R4
fhir.r4.ukcore.stu3.currentbuild	fhir.r4.ukcore.stu3.currentbuild#0.0.19-pre-release	R4
Genomics Reporting Implementation Guide	hl7.fhir.uv.genomics-reporting#3.0.0	R4
HL7 Terminology (THO)	hl7.terminology.r4#6.1.0	R4
FHIR Extensions Pack	hl7.fhir.uv.extensions.r4#5.1.0	R4
HL7 Europe Laboratory Report	hl7.fhir.eu.laboratory#0.1.1	R4
HL7 Terminology (THO)	hl7.terminology.r4#6.2.0	R4
International Patient Summary Implementation Guide	hl7.fhir.uv.ips#1.1.0	R4
HL7 Terminology (THO)	hl7.terminology.r4#5.0.0	R4
fhir.dicom	fhir.dicom#2022.4.20221006	R4
Structured Data Capture	hl7.fhir.uv.sdc#3.0.0	R4
FHIR Tooling Extensions IG	hl7.fhir.uv.tools.r4#0.8.0	R4	for example references

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