Lupus induced by Isoniazid

Introduction. The drug-induced lupus represents 10% of lupus. Several drugs are involved. Among the antituberculous, the most incriminated is Isoniazid. The overall incidence of adverse effects of this antituberculous is estimated at about 5% of patients treated. They correspond mainly to liver damage and nervous system, rarely a lupus syndrome: the isoniazidinduced lupus occurs in less than 1% of cases and is completely regressive at stopping treatment. The diagnosis of drug-induced lupus is done front of clinical symptoms of lupus, positive antinuclear antibody without a history of systemic lupus erythematosus associated with the improvement after elimination of the drug abuser. Antibodies anti-histones are found in 75% of lupus drug against 20% of idiopathic lupus. Observation. We report the case of a patient of 27 years, without medical history including no lupus, treated with rifampicin, isoniazid and pyrazinamide for smear-negative pulmonary tuberculosis, who presents, a month after starting treatment, warm Generalized erythematous Rash associated with arthralgia. The diagnosis of lupus is held front of this clinical symptomatology associated with positive antinuclear antibodies and positive anti-histone. After discontinuation of isoniazid, an improvement in clinical symptoms was noted, and a negativity of Immunological at the third week after the arrest. Conclusion. Lupus induced by isoniazid is a rare (less than 1% of induced lupus) whose mechanisms remain poorly understood. The diagnosis is difficult due to the absence of clear consensus