Relapsed hydroxychloroquine induced thrombocytopenia in a systemic lupus erythematosus patient.

Hydroxychloroquine is used in the long-term therapy of systemic lupus erythematosus (SLE). Although considered to be a safe treatment, side effects have been documented. An uncommon side effect is thrombocytopenia. In order to establish the diagnosis of thrombocytopenia secondary to Hydroxychloroquine, non-pharmacological causes must be ruled out and it is necessary to determine a recurrence after re-exposure to the drug. We present one case of severe thrombocytopenia occurring in a patient with SLE undergoing treatment with Hydroxychloroquine.