Jvahmed

Alveolar Lung Disease

Causes:

Alveolar lung disease may be divided into acute or chronic. Causes of acute alveolar lung disease include pulmonary edema (cardiogenic or neurogenic), pneumonia (bacterial or viral), pulmonary embolism, systemic lupus erythematosus, bleeding in the lungs (e.g., Goodpasture syndrome), idiopathic pulmonary hemosiderosis, and granulomatosis with polyangiitis.

Chronic alveolar lung disease can be caused by pulmonary alveolar proteinosis, alveolar cell carcinoma, mineral oil pneumonia, sarcoidosis (alveolar form), lymphoma, tuberculosis, metastases, or desquamative interstitial pneumonia.

Development of the Disease

Diagnosis

Initial evaluation and Testing

Patients with alveolar lung disease may have cough or difficulty breathing.

A physician will listen to the patient’s lungs to help determine if there is likely a lower lung disease. Depending on the type of alveolar lung disease, the listener may hear “crackles” that indicate an excess of fluid in the lungs or an absence of lung sounds in certain regions which may indicate poor ventilation due to consolidation of pus or fibrosis.

A pulse oximeter is a device that measures the amount of oxygen available in the blood. This is an important measurement in evaluation of a patient with difficulty breathing with suspected alveolar lung disease.

Imaging

Chest x-ray is the initial imaging modality of choice for evaluation of potential alveolar lung disease. Bedside ultrasound may also be utilized.

The absence of radiographic evidence early on in the course of disease does not exclude alveolar disease.

Alveolar disease is visible on chest radiography as small, ill-defined nodules of homogeneous density centered on the acini or bronchioles. The nodules coalesce early in the course of disease, such that the nodules may only be seen as soft fluffy edges in the periphery.

When the nodules are centered on the hilar regions, the chest x-ray may develop what is called the "butterfly," or "batwing" appearance. The nodules may also have a segmental or lobar distribution. Air alveolograms and air bronchograms can also be seen.

These findings appear soon after the onset of symptoms and change rapidly thereafter.

A segmental or lobar pattern may be apparent after aspiration pneumonia, atelectasis, lung contusion, localized pulmonary edema, obstructive pneumonia, pneumonia, pulmonary embolism with infarction, or tuberculosis.

Lab

Treatment

The focus of treatment for alveolar disease is typically to maintain oxygenation and ventilation to ensure that adequate oxygen is being delivered to blood, and to resolve the underlying insult to the alveoli.

Maintaining oxygenation and ventilation in alveolar lung disease is achieved through a number of methods. The mechanism of these treatments is primarily to keep the alveoli open so that they can take up oxygen from and deliver it to the bloodstream.

In cases where methods to support the lungs to provide oxygen to the blood fail, ECMO, or extracorporeal membrane oxygenation can be considered.

Treating underlying causes of damage to alveoli is also essential in most alveolar lung disease.  

Some more commonly seen instances of alveolar lung disease include pulmonary edema and pneumonia.

Pulmonary edema can be cardiogenic or non-cardiogenic.

For cardiogenic pulmonary edema, medical treatment in addition to measures to maintain ventilation include diuretics to remove excess fluid from the lungs.

In viral pneumonia

Sources:

https://link.springer.com/chapter/10.1007/978-3-642-03709-2_19

https://books.google.com/books?id=LxdsAAAAMAAJ&q=%22Alveolar+lung+disease%22+-wikipedia&dq=%22Alveolar+lung+disease%22+-wikipedia&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwj59Ynx2sLoAhV8hHIEHTRGC64Q6AEwCHoECAgQAg

Pulmonary physiology in lung disease