Pneumocystis jiroveci pneumonia secondary to blinatumomab therapy: a case report

Abstract

Background With the increasing use of Blinatumomab in relapsed or refractory, as well as MRD-positive, B-cell precursor acute lymphoblastic leukemia (ALL), the recognition of its adverse effects has gradually improved, in which pneumocystis jiroveci pneumonia (PCP) is rare. Case presentation We present a case of PCP in patients undergoing Blinatumomab therapy. A 70-year-old female patient diagnosed with Philadelphia-like, CRLF2 overexpression B-cell precursor ALL received Blinatumomab as consolidation therapy after achieving complete remission with prior induction chemotherapy. On the second day of Blinatumomab infusion, she developed intermittent low-grade fever with chest computed tomography revealing subtle infiltrates and nodules. Though empirically treated with trimethoprim-sulfamethoxazole (TMP-SMX) for PCP prophylaxis, she progressed to significant shortness of breath and type I respiratory failure, with increased lactate dehydrogenase and β-D-glucan assays. Chest computed tomography showed diffuse ground-glass opacities with scattered small nodules. Because of dry cough, next-generation sequencing of peripheral blood was tested and showed positive for pneumocystis jiroveci without evidence of other pathogens. Consequently, the patient was diagnosed with PCP. The first cycle of Blinatumomab had to be discontinued, and therapeutic dosages of TMP-SMX and dexamethasone were administered, followed by a full recovery and stable station during follow-ups. Discussion PCP was rare in B-cell precursor ALL patients receiving blinatumomab therapy, but is early onset and with rapid disease progression. Besides, PCP infection could not be ignored though prophylaxis has been given. Thus, more attention should be paid to when using blinatumomab therapy.