Ct shows 2 mm & smaller indeterminant pulmonary nodules, in the right lower lobe. tiny subpleural lymph nodes along the fissures. what causes this?

Pulmonary nodule: Scarring, infection, or benign granulomatous disease can cause small lung nodules. When they are very small such as 2 mm they cannot be easily characterized on ct scan and normally it suggested for a repeat ct of the thorax in 3 to 6 months to monitor any growth or progression of disease. If the findings are stable it suggest a benign cause if there is enlargement then a pet scan or biopsy may be indicated.

A lot of things: If just 2 mm, i would just monitor with a ct scan every 6 months for a year and then every year thereafter. Possibilties include exposure to fungus, old infection, dust or malignancy but this is less likely. Hope this helps.