CD4 and B-cell chronic lymphocytic leukemia: These PcP cases occurred in previously untreated CLL patients receiving ibrutinib monotherapy and presented in a “nontypical” way [100]: (a) patients were asymptomatic or had only mild, often chronic respiratory symptoms; (b) there was no long-term use of steroids or other immunosuppressive drugs; (c) chest computed tomography scan revealed nontypical multifocal nodular infiltrates; (d) CD4+ T-cell counts were high (>500 per microliter), (e) and no patient required intravenous therapy, adjunctive steroid treatment or mechanical ventilation.