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Quinidine-induced lupus erythematosus.
Annals of Internal Medicine
|June 1, 1984
Summary
Quinidine therapy can trigger drug-induced antinuclear antibodies (ANA) primarily targeting histones. Discontinuation of quinidine led to symptom resolution and normalization of these autoantibodies.
Area of Science:
- Rheumatology
- Clinical Immunology
- Pharmacology
Background:
- Drug-induced autoimmune syndromes are increasingly recognized.
- Quinidine, an antiarrhythmic drug, has been implicated in various adverse reactions.
Observation:
- A 60-year-old male developed fever, polyarthritis, pleurisy, and lymphopenia during quinidine treatment.
- Antinuclear antibody (ANA) testing became positive after five months of quinidine therapy.
Findings:
- The patient's quinidine-induced ANAs were of IgM and IgG classes.
- These autoantibodies predominantly targeted nuclear histones (H1 and H2B).
- Antibodies to native DNA and nonhistone antigens were absent.
Implications:
- This case highlights quinidine as a potential cause of drug-induced lupus-like syndrome.
- The findings suggest histone-specific autoantibodies may be a marker for quinidine-induced autoimmunity.
- Prompt withdrawal of the offending drug is crucial for managing such conditions.
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