Lymphocyte dynamics as the central mediator in osimertinib-induced CD4+ T-cell depletion, fulminant cytomegalovirus pneumonitis, and progressive pulmonary fibrosis: a case report
Year: 2025
Type: article
Study design: Case Report
Abstract: Osimertinib-induced severe lymphocytopenia can create a profound immunodeficiency state, facilitating opportunistic infections and progressive fibrotic lung disease. A 75-year-old female with EGFR-mutant NSCLC developed respiratory failure with diffuse ground-glass opacities and profound lymphocytopenia (ALC 0.48×10 9 /L). Overreliance on BAL-NGS detection of Mycobacterium avium complex delayed diagnosis of cytomegalovirus pneumonia. Guideline-discordant erlotinib rechallenge accelerated lymphocyte depletion, culminating in high-grade CMV viremia with CD4 + lymphocytopenia (0.16×10 9 /L) and irreversible pulmonary fibrosis despite ganciclovir-induced virologic clearance. This case demonstrates an immune-fibrotic axis wherein TKI-induced lymphocytopenia enables CMV pneumonitis and fibrotic remodeling. Lymphocytopenia in this setting mandates urgent viral exclusion before attributing injury to drug toxicity and precludes TKI rechallenge during active infection or severe immunosuppression. BAL-NGS requires rigorous clinicoradiologic correlation.
Source: Frontiers in Immunology
Institution: Yangtze University
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $3,801
OpenAlex ID: W4417415187
