Pneumocystis jirovecii pneumonia after CD4+ T-cell recovery subsequent to CD19-targeted chimeric antigen receptor T-cell therapy: A case report and brief review of literature.

The patient in the present case developed PJP despite a CD4+ T-cell count of >200/μL after CAR-T cell therapy, probably because of inadequate CD4+ T-cell activation caused by B-cell depletion after CAR-T cell therapy and repeated abnormal macrophage immune responses after CBT. It is important to determine the duration of TMP/SMX for prophylaxis after CAR-T cell therapy according to each case, as well as the CD4+ T-cell count.