Target sign of the lung

Area of Science:

• Pulmonology
• Radiology
• Toxicology

Background:

• The lung target sign is a specific radiological finding characterized by a ring-like opacity and a central nodule.
• Previously, this sign was exclusively documented in cases of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection and organizing pneumonia.

Observation:

• This report details a case presenting a lung target sign.
• The patient's clinical presentation and history were evaluated for potential causes of this radiological finding.

Findings:

• The observed lung target sign was not associated with SARS-CoV-2 infection or organizing pneumonia.
• The findings suggest a potential link between the target sign and drug-induced lung injury, representing a novel association.

Implications:

• This discovery expands the differential diagnosis for the lung target sign.
• It highlights the importance of considering medication side effects in patients presenting with this radiological pattern.
• Further research is warranted to confirm this association and elucidate the underlying mechanisms of drug-induced lung injury presenting as a target sign.