Differential Diagnosis for Bilateral Perihilar and Lower Lung Infiltrates
Single Most Likely Diagnosis
- Heart Failure: This is often the most common cause of bilateral perihilar infiltrates, especially in the context of known heart disease. The infiltrates are due to pulmonary edema, which can also extend to the lower lobes, especially if the condition is severe.
Other Likely Diagnoses
- Pneumonia (Community-Acquired or Hospital-Acquired): Various types of pneumonia can present with bilateral lung infiltrates. The distribution can vary but often involves the perihilar regions and can extend to the lower lobes.
- Chronic Obstructive Pulmonary Disease (COPD) Exacerbation: Patients with COPD can develop worsening symptoms and bilateral infiltrates due to an exacerbation, often triggered by an infection or air pollution.
- Asthma Exacerbation: Severe asthma attacks can lead to bilateral infiltrates, particularly if there is associated allergic bronchopulmonary aspergillosis or other complicating factors.
- Interstitial Lung Disease (ILD): Certain types of ILD, such as nonspecific interstitial pneumonia (NSIP) or cryptogenic organizing pneumonia (COP), can present with bilateral infiltrates that may have a perihilar and lower lobe distribution.
Do Not Miss Diagnoses
- Pulmonary Embolism: While pulmonary embolism typically presents with unilateral findings, bilateral emboli can occur, and the diagnosis is critical due to its high mortality rate if untreated.
- Acute Respiratory Distress Syndrome (ARDS): This is a life-threatening condition characterized by rapid onset of widespread inflammation and injury to the lungs, leading to bilateral infiltrates on imaging.
- Influenza or Other Viral Pneumonias: Especially during outbreaks, these can present with severe bilateral pneumonia and are critical to diagnose due to the potential for severe illness and the need for specific antiviral treatment.
Rare Diagnoses
- Eosinophilic Pneumonia: A rare condition characterized by an accumulation of eosinophils in the lungs, which can present with bilateral infiltrates.
- Lymphangitic Carcinomatosis: Metastatic disease to the lungs that can cause bilateral infiltrates, particularly in a perihilar distribution.
- Sarcoidosis: An autoimmune disease that can affect the lungs, among other organs, and present with bilateral hilar lymphadenopathy and lung infiltrates.
- Idiopathic Pulmonary Hemosiderosis: A rare condition characterized by recurrent episodes of diffuse alveolar hemorrhage, leading to bilateral lung infiltrates.