Anti-Nuclear Antibody (ANA) Connective Tissue Disease (CTD) Screen & ANA Hep2 immunofluorescence (IIF)
The presence of ANA is a gateway criteria for the diagnosis of SLE (EULAR/ACR 2019). ANA are also found in a number of other autoimmune diseases, such as Sjögren’s syndrome (60%), rheumatoid arthritis, autoimmune liver disease, scleroderma, mixed connective tissue disease, poly/dermatomyositis, Hashimoto’s thyroiditis and autoimmune haemolytic anaemia. A positive ANA is a risk factor for uveitis in patients with juvenile idiopathic arthritis (JIA).
Weak positive (titres up to 1/320) ANA reactions are not uncommon, especially in the elderly, and may have no clinical significance. ANA may be present during acute and chronic infection.
The laboratory performs a connective tissue disease (CTD) screen (ANA screen) first line for the most common ANA. Any positive results will be further tested by ANA immunofluorescence (Hep2 IIF, ANA IIF) and confirmatory ENA profile plus quantitative double stranded DNA antibodies. ANA IIF is reported in accordance with the International Consensus on ANA Patterns (ICAP) recommendations and more details of pattern associations can be found on their website https://anapatterns.org/index.php.
The CTD screen is a bead based fluoroenzymeimmunoassay containing the following recombinant antigens; dsDNA, Ro52, Ro60, SSB/La, Sm, U1RNP (RNP-70, A, C), Jo-1, Scl-70, CENP-B, Mi-2, RNA Pol III, PM-Scl, PCNA, Ribosomal P, and Fibrillarin.
Suspected connective tissue disease.
Suspected autoimmune liver disease (request ANA IIF and liver autoantibody screen).
ANA Immunofluorescence = Negative titre <1/160 (range verified in house)
CTD screen = Negative ratio <0.7 (range verified in house)
Record last updated
August 13, 2025
Sample Container
5ml RST Vacutainers (Rust top)
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Test Results
Yes, we have a Pathology User Guide
Yes. Please email your request to Imperial.nwlpcustomerservice@nhs.net
Results are communicated to clinical staff and are normally not communicated direct to patients either on telephone requests or in written report. If you need to contact us please click here to view the contact details page
Please contact the Customer Service Team Monday to Friday from 8:30am – 6:00pm on 0203 313 5353. Alternatively, see the Pathology User Guide for how to contact the relevant department. If advice is not urgent you can also email your query to Imperial.nwlpcustomerservice@nhs.net
Additional tests may be added by discussion with the relevant laboratory. The time limit for adding additional tests to a sample already received in the laboratory will depend on the type of sample and the department it was sent to.
Information on the repertoire of tests performed by pathology, including reference ranges, turnaround times and specimen requirements, can be found in the test directory.
Phlebotomy services are not managed by NWLP. For further information please see:
Imperial College Healthcare Trust Phlebotomy services
Chelsea and Westminster Hospital NHS Foundation Trust Phlebotomy services
NWLP operates UKAS accredited medical laboratories as per the references below. The current scope of accreditation for all NWLP’s laboratories can be found on the UKAS website.
See the following UKAS ref numbers:
- Clinical Biochemistry Ref: 8673
- Haematology and Blood Transfusion Ref: 8674
- Infection & Immunity Sciences (Including Immunology, Virology, Microbiology and Histocompatibility and Immunogenetics ) Ref: 8659
- Cellular Pathology (Including Histopathology, Cytology and Molecular Pathology) Ref: 9615
If you require copies of our certificate of accreditation and associated documentation please contact Imperial.nwlpcustomerservice@nhs.net.
UKAS requires the laboratories to be accredited for a particular repertoire/scope (ISO15189), any changes or additions to repertoire require assessment by UKAS (extension to scope).
The BD Hospital Tube Guide, BD GP Tube Guide and BD Paediatric Tube Guide provide visual references to the correct tube types and collection instructions.
Home testing
INSTRUCTION SHEET FOR BLOOD SAMPLE COLLECTION
We also have two instruction videos available (one with subtitles and one without) – please click on the links to view the videos on Google.
Our accreditations
Upholding excellence in diagnostic standards
Our laboratories are accredited by the UK Accreditation Service (UKAS) against the international standard ISO15189:2022. UKAS is the accreditation body for the UK that assesses medical laboratories.
Find out more about our accreditations on the UKAS website.
UKAS website