A Novel Case of Cytomegalovirus Pneumonia in an Acquired Thrombotic Thrombocytopenic Purpura Patient Treated With Rituximab.

Thrombotic thrombocytopenic purpura (TTP) is thrombotic microangiopathy that is universally fatal if not promptly recognized and treated. Standard treatment includes plasma exchange (PLEX) therapy and immunosuppression. We present a case of an 80 years old African American male with a past medical history significant for essential hypertension, chronic obstructive pulmonary disease, and a recent TTP diagnosis for which he was treated with PLEX, glucocorticoids, and rituximab. The patient presented with complaints of shortness of breath of four days duration. He was hypoxemic on presentation; other vital signs were within normal limits. The basic metabolic panel and complete blood count were unremarkable. A computed tomography (CT) of the chest with contrast showed right lower lobe segmental and subsegmental pulmonary emboli. He was initiated on intravenous heparin therapy. During hospitalization, he had progressive clinical deterioration with progressive hypoxemia. A repeat CT scan demonstrated bilateral pulmonary infiltrates. The patient underwent bronchoscopy due to concerns of opportunistic infections in view of his recent immunosuppressive treatment. Bronchoalveolar lavage revealed cytomegalovirus (CMV), and the patient was initiated on ganciclovir. CMV pneumonia has been reported after rituximab therapy in patients with lymphomas and lymphoproliferative disorders. To our knowledge, this is the first case of CMV pneumonia after rituximab therapy in a patient with TTP.