Rare diseases · Sign or symptom
Pulmonary opacity
HP:0031457
What it means
Opacity refers to any area that preferentially attenuates the x-ray beam and therefore appears more opaque than the surrounding area. It is a nonspecific term that does not indicate the size or pathologic nature of the abnormality.
Increased pulmonary opacity is caused by a decrease in the ratio of gas to soft tissue (blood, lung parenchyma and stroma) in the lung.
Rare diseases that can present with this4
Common30–79%
3The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.
Part of the broader category
Tracking symptoms like this for someone? Eleplan keeps symptoms, diagnoses, medications and every specialist in one plan.
Start free with EleplanThis page uses the Human Phenotype Ontology (2026-06-23) — Human Phenotype Ontology Consortium, hpo.jax.org. Disease associations from Orphanet (INSERM), CC BY 4.0. Content is educational and is not medical advice.