Hello,

Thanks for posting your query.

On an x-ray, four basic densities exist: air, fat, fluid filled tissue, and bone.

Bone appears the whitest on x-ray because it is the densest and the other tissues are relatively less dense with air filled lung tissues being radiolucent appearing black.
On x-ray chest if there are patchy densities in the region indicating lung tissue then they are called infiltrates.

Prominent infiltrates are commonly seen due to inflammatory fluid in lung parenchyma either due to infection or hemorrhage or any pathology like malignancy, etc. In pneumonia the infiltrates will be more dense and localized to a particular lobe and called consolidation on x-ray finding.
But sometimes in systemic infections there may be some chest congestion and mild infiltrates visible on chest x-ray bilaterally, which may be normal or temporary due to increased blood circulation.

So the bottom line is pulmonary infiltrates on x-ray can be of any reason from normal to serious pneumonitis. And clinical correlation is very important for diagnosis.

In your case you seem to be having a respiratory infection causing infiltrates in lung and which is being appropriately treated with antibiotics (azithromycin). It is likely to resolve after adequate treatment.

Hope I have answered your query. Please accept my answer in case you do not have further queries.

Regards

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