Drug-Induced Lupus Erythematosus

The clinical and serologic picture of drug-induced lupus erythematosus is often indistinguishable from that of SLE.
A syndrome resembling SLE can be induced by certain drugs: hydralazine, procainamide, phenytoin, isoniazid, quinidine, beta-blockers, sulfasalazine, minocycline, and lithium; however, patients with drug-induced lupus syndromes develop cutaneous lesions much less commonly than is typically seen in SLE.
Arthralgia or arthritis, generally affecting the small joints, is often the only clinical symptom. Myalgia, pleuritis, pericarditis, fever, and hepatosplenomegaly may occur.
The classic SLE-type skin lesions such as the butterfly rash and mucosal ulcerations are usually absent in drug-induced lupus erythematosus. CNS manifestations and renal involvement are also rare.
In 90% of patients, ANAs are present in a homogenous or speckled pattern.
Withdrawal of the offending drug, followed by a regression of symptoms, helps confirm the diagnosis

Management

Sun-related Symptoms

Excessive sun exposure should be avoided and the patient should be counseled in the use of broad-spectrum sunscreens.

Severely Ill Patients

The mainstays of therapy for systemic disease are systemic steroids (prednisone), given in a dosage of 0.5 to 1 mg/kg/day.
Administration of oral antimalarials such as hydroxychloroquine(Plaquenil) and chloroquine (Aralen) are sometimes used as first-line therapy. They both may be very effective in the treatment of skin lesions and as steroid-sparing agents.

Other therapeutic agents include the following:

Dapsone, gold, oral retinoids such as isotretinoin (Accutane), and immunosuppressive drugs such as azathioprine (Imuran) and cyclophosphamide (Cytoxan) and methotrexate may be helpful.
Mycophenolate (CellCept) as well as interferon alpha-2a and alpha-2b (Roferon and Intron A) may also be administered.
Immunosuppressive agents are used as adjuvant therapy to treat systemic disease due to their steroid-sparing effects.
Thalidomide and intravenous g-globulin are used to control recalcitrant cases.