Abstract
Idelalisib, a phosphoinositide 3-kinase delta (PI3Kδ) inhibitor, effectively treats relapsed chronic lymphocytic leukemia (CLL). While this targeted approach offers a therapeutic edge, particularly in B-cell malignancies, it is associated with complications such as pneumonitis. This report details idelalisib-induced pneumonitis, highlighting the importance of early diagnosis and tailored treatment in achieving a favorable patient outcome.