Skip to content

Scl-70 Antibody

Published: July 27, 2026Updated: August 25, 2026

The Scl-70 antibody is a specific marker used to aid in the diagnosis of systemic sclerosis (scleroderma), an autoimmune connective tissue disorder.

Quick summary

Scl-70 antibody is a diagnostic marker for systemic sclerosis.

Medically reviewed by WellAlly Editorial TeamLast reviewed August 25, 2026Editorial policy

Key facts at a glance

Units
U/mL
Clinical utility
diagnostic
Result kind
quantitative
FDA-cleared
Roche Scl-70, Abbott Scl-70, Siemens Scl-70
interpretation: {"text":"Scl-70 antibody levels within the reference range (0–20 U/mL) suggest a low likelihood of systemic sclerosis.","label":"Negative"}; {"text":"Levels above 20 U/mL may indicate the presence of systemic sclerosis, warranting further clinical evaluation.","label":"Positive"}

Scl-70 antibody is an antinuclear antibody (ANA) that targets DNA topoisomerase I, an enzyme involved in DNA replication and transcription. Its presence is highly specific for systemic sclerosis, particularly the diffuse cutaneous form.

The detection of Scl-70 antibodies in patient serum can help clinicians confirm a diagnosis of systemic sclerosis, especially when clinical symptoms are ambiguous. It is often used in conjunction with other diagnostic tools.

Levels of Scl-70 antibodies are typically reported in U/mL, with a reference range of 0–20 U/mL. Elevated levels beyond this range may indicate the presence of systemic sclerosis.

Frequently asked questions

What is the significance of a positive Scl-70 antibody test?
A positive test indicates a high specificity for systemic sclerosis, particularly the diffuse form, and can aid in early diagnosis and management.
Can Scl-70 antibodies be present in other conditions?
While Scl-70 antibodies are highly specific for systemic sclerosis, they may occasionally be found in patients with other autoimmune disorders, albeit at lower frequencies.
  1. 1
    Systemic Sclerosis: Diagnosis and ManagementSource
  2. 2
    Antinuclear Antibodies (ANA) TestSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 25, 2026. · Read our editorial policy