Lung abscess: what it is, symptoms, causes and treatment

A lung abscess is a cavity that contains pus inside, caused by necrosis of the lung tissue, due to a microbial infection.

Generally, the abscess forms between 1 and 2 weeks after contamination by the microorganism, which, in most cases, occurs due to a complication of pneumonia caused by aspiration of the contents of the mouth or stomach, as they contain bacteria more prone to developing this type. of injury. Understand how aspiration pneumonia arises.

The diagnosis is made by the doctor through evaluation of the clinical picture, lung radiography and blood tests. Then, it is essential to start treatment with antibiotics that help fight the causing microorganisms, in association with nutritional support and physiotherapy. In more serious cases, lung drainage may be necessary.

Lung abscess symptoms

The main symptoms of lung abscess include:

• Fever;
• Shortness of breath and tiredness;
• Cough with mucopurulent secretion, which may contain an unpleasant odor and streaks of blood;
• Chest pain that worsens with breathing;
• Loss of appetite;
• Weight loss;
• Night sweats and chills.

The worsening of the clinical condition can take days to weeks, depending on the bacteria that caused the infection, the health conditions and defenses of the affected person’s body. Generally, only one abscess is formed, measuring more than 2 cm in diameter, however, in some cases multiple abscesses may appear during the infection.

When signs and symptoms appear that may indicate this type of lung infection, it is necessary to consult a pulmonologist as soon as possible, or go to the emergency room, so that the cause can be identified and appropriate treatment can be started immediately.

How is the diagnosis

The diagnosis of lung abscess is made by the doctor, through the analysis of symptoms, physical examination, in addition to tests such as chest x-ray, which demonstrates the presence of secretion infiltrates in the lung and the cavitation area, generally rounded, filled with pus and air.

Blood tests, such as a blood count, can help demonstrate the presence of an infection and assess its severity. Computed tomography of the chest can help to better define the location of the abscess, and observe other complications such as a lung infarction or accumulation of pus in the pleural fluid.

Identification of the microorganism may be necessary in some cases, especially to guide treatment, and for this purpose a lung sputum culture may be performed, or material from the infection may be collected by tracheal aspirate or thoracentesis, for example, or even by blood culture. . See how the exam is performed to identify the best antibiotic to treat the infection.

What causes lung abscess

Lung abscess is caused when microorganisms, usually bacteria, settle in the lung and cause necrosis of its tissue. The penetration of microorganisms can occur through the following mechanisms:

• Aspiration of infectious material (most common cause): more common in cases of alcoholism, drug use, coma or anesthesia, in which loss of consciousness facilitates the aspiration of contents from the mouth or stomach, as well as in cases of sinusitis, infections in the gums, tooth decay or even when you are unable to cough effectively;
• Pulmonary infection;
• Cancer;
• Direct traumatic penetrations into the lungs;
• Spread of infections from a neighboring organ;
• Pulmonary embolism or infarction.

When lung abscess arises from direct infection of the lung, it is characterized as primary. In cases where it arises due to complications of pulmonary changes, such as the spread of an infection from other organs or a pulmonary embolism, it is called secondary.

Some of the most common microorganisms causing lung abscess are Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa or Streptococcus pyogenes, or anaerobic bacteria, such as Peptostreptococcus, Prevotella or Bacteroides sp, for example. Abscesses caused by fungi or mycobacteria are rarer and appear more frequently in people with very weakened immunity.

How the treatment is carried out

Treatment for lung abscess involves the use of antibiotics such as Clindamycin, Moxifloxacin or Ampicillin/Sulbactam, for example, for an average of 4 to 6 weeks, depending on the causative microorganism and the patient’s clinical conditions.

During the acute phase, nutritional support and respiratory physiotherapy are also indicated. If the initial treatment is not effective, surgery must be performed to drain the abscess, and as a last resort, remove the part of the necrotic lung.

Physiotherapy for Lung Abscess

Physiotherapy is important to aid recovery, and is done through:

• Postural Drainage: after locating the lung abscess, the individual is positioned towards the source bronchus for subsequent elimination of secretions through coughing;
• Respiratory kinesiotherapy: breathing exercises are aimed at increasing chest expansibility and normalizing lung volumes;
• Incentive spirometry: the person is instructed to inhale deeply (pull air into the lungs) and hold it for a few seconds. It can be done using devices such as Respiron;
• Aspiration of secretions if the person is unable to cough.

Physiotherapy for lung abscess is most effective in collaborative people who respond to requests for coughing and breathing exercises. Find out more about how respiratory physiotherapy is done and what it is for.