From the Guidelines
Medications such as hydralazine, procainamide, and tumor necrosis factor (TNF) inhibitors like etanercept can induce a positive Antinuclear Antibody (ANA) test. The development of a positive ANA test can occur in patients taking certain medications, including anti-TNF agents, as reported in a study published in the Journal of the American Academy of Dermatology 1. Some of the key medications that can cause a positive ANA test include:
- Hydralazine
- Procainamide
- Isoniazid
- Minocycline
- Certain anticonvulsants like phenytoin and carbamazepine
- Chlorpromazine
- Methyldopa
- Quinidine
- TNF inhibitors such as infliximab and etanercept
- Biologics, including anti-TNF agents and interferon therapy
- Certain antibiotics like sulfasalazine and tetracyclines These medications can induce autoantibody production by altering self-antigens, promoting immune complex formation, or directly activating lymphocytes. When evaluating a positive ANA test, it's essential to obtain a thorough medication history to identify potential drug-induced causes before pursuing extensive autoimmune workups, as drug-induced ANA positivity generally doesn't require immunosuppressive treatment beyond stopping the causative medication, as noted in the context of anti-TNF therapy 1.
From the FDA Drug Label
Laboratory Tests Complete blood counts and antinuclear antibody titer determinations are indicated before and periodically during prolonged therapy with hydrALAZINE even though the patient is asymptomatic A positive antinuclear antibody titer requires that the physician carefully weigh the implications of the test results against the benefits to be derived from antihypertensive therapy with hydrALAZINE Laboratory tests such as complete blood count (CBC), electrocardiogram and serum creatinine or urea nitrogen may be indicated depending on the clinical situation, and periodic rechecking of the CBC and ANA may be helpful in early detection of untoward reactions
Medications that can induce a positive Antinuclear Antibody (ANA) test:
Key points:
- Both hydralazine and procainamide can induce a positive ANA test.
- Patients should be monitored for signs of autoimmune disorders when taking these medications.
- The decision to continue therapy should be weighed against the potential benefits and risks.
From the Research
Medications that Induce a Positive ANA Test
Medications can induce a positive Antinuclear Antibody (ANA) test, which is a common marker for autoimmune disorders such as Systemic Lupus Erythematosus (SLE). The following medications have been associated with a positive ANA test:
- Hydralazine 4, 5, 6, 7, 8
- Procainamide 4, 5, 7, 8
- Isoniazid 4, 5, 7, 8
- Methyldopa 4, 7
- Chlorpromazine 4, 7
- Quinidine 4, 7
- Minocycline 4, 8
- Calcium channel blockers 5, 8
- Angiotensin-converting enzyme inhibitors 5, 8
- Thiazide diuretics 5, 8
- Terbinafine 5, 8
- Tumor necrosis factor (TNF)-alpha antagonists 5, 8
- Fluorouracile agents 8
- Interferons 5, 7
- Beta-blockers 7
- Sulfonamides 7
- Sulfasalazine 7
- Penicillamine 7
Mechanism of Action
The exact mechanism of how these medications induce a positive ANA test is not fully understood, but it is thought to be related to the interaction between the drug and DNA or histones, rendering them immunogenic 7. In some cases, it may be due to disruption of the cytokine network 7.
Clinical Presentation
The clinical presentation of drug-induced lupus can vary, but it is often characterized by arthralgia, myalgia, pleurisy, rashes, and fever, in association with antinuclear antibodies in the serum 7. More serious features of idiopathic lupus, such as nephritis and cerebral disease, are rare in drug-induced disease 7.