Perihilar infiltrates are found on imaging studies of the chest like X-rays and CT. The term perihilar infiltrates does not indicate a specific diagnosis but is a descriptive term to describe an observed abnormality.
Perihilar infiltrates meaning
The hila are seen on the right and left sides where the lung meets the mediastinum. This is the root of the lung on each side. The blood vessels and bronchi (airways) enter and leave the lungs here. This is located midway up the chest on the inner part of the lungs where they meet the mediastinum.
Anything that causes the normal air filled dark lungs to lose this appearance and be whiter can be referred to as perihilar infiltrates. This can be on one or both sides. This term does not imply a specific diagnosis but simply that an abnormality is observed around the hila.
Causes of perihilar infiltrates
Infections are perhaps the most common appearance that can cause perihilar infiltrates or loss of normal lung appearance around the hila. Pneumonia can commonly have this appearance. Viral pneumonia in kids can give this appearance.
Pulmonary edema can cause perihilar infiltrates. There may be additional helpful findings and clinical history to indicate this diagnosis.
Inhalational injury, bleeding into the lungs, and certain cancers can also occasionally have this appearance.
Bilateral perihilar infiltrates
This means we see the infiltrates on the right and left sides. This can tell us that process is more extensive and involves both lungs.
Unilateral (left or right) perihilar infiltrates
This is an infiltrate that is seen only on one side around the hilum. This can tell us that the process is more localized to one area. This may help us narrow the diagnostic possibilities.
Perihilar infiltrates on X-ray
Perihilar infiltrates on X-ray appear as white areas around the hila. Normally the lung is black in this region. There can be thickening of the bronchi depending on the cause. There can be associated findings in the lungs which can help narrow the diagnosis.
Perihilar infiltrates symptoms
The symptoms often depend on the cause. Pneumonias may have more recent onset with cough, fever, and breathlessness while cancer is a more long standing progressive process.
Pulmonary edema or fluid in the lungs may be seen from multiple causes but is commonly seen in patients with heart failure.
Bleeding into the lungs may be associated with coughing up blood.
Are perihilar infiltrates dangerous?
They can be depending on the cause. While viral pneumonias often go away with time and supportive care, pulmonary edema and cancerous perihilar infiltrates will require more specific treatment.
Perihilar infiltrates treatments
The treatment will depend on the cause of the perihilar infiltrates. Some pneumonias may require antibiotics while others need supportive care like viral pneumonias. Cancerous perihilar infiltrates may need chemotherapy or other cancer treatments. Fluid in the lungs will be treated based on the cause.
Perihilar infiltrates: summary
Perihilar infiltrates is an abnormality seen on chest X-rays and CT around the hila either on one or both sides. This means that the normally dark air filled lung is replaced with a whiter appearance. There are multiple causes of perihilar infiltrates. Other imaging findings and the clinical history can help us narrow the diagnosis.