[Thrombocytopenia induced by rifampicin not previously sensitized: a case presentation]

Thrombocytopenia induced by rifampicin in the absence of prior sensitization is exceptional, especially when it occurs in a patient without risk factors. We report the case of a patient aged 25 years with no past history of medical, surgical or knowledge of having taken rifampicin previously, who was hospitalized for treatment of thrombocytopenic purpura occurring after the initiation of fixed combination quadruple therapy (isoniazid, rifampicin, pyrazinamide and ethambutol) for pulmonary tuberculosis. The biological pretreatment and therapeutic education had not been made. The patient presented with thrombocytopenic purpura 30000/mm(3) on day 9 after the initiation of treatment. The platelet count returned to normal 10 days after discontinuation of treatment. We elected not to reintroduce rifampicin given the strong likelihood that it was responsible for this complication. We conducted a phased reintroduction of isoniazid, ethambutol and pyrazinamide. No recurrence of the thrombocytopenia occurred. Thus, the diagnosis of rifampicin-induced thrombocytopenia appears to have been confirmed and the patient tolerated the remainder of their treatment well.