A pleural rub is a distinctive sound heard during auscultation of the chest. It is caused by friction between the pleural membranes as a result of loss of lubrication and indicates an inflammatory process is occurring inside the patient’s chest. The sounds can be indicative of a number of different medical conditions. Interviewing the patient and completing an exam can provide a doctor with more information to use in the development of a diagnosis.
In healthy individuals, a layer of lubrication separates the pleural membranes, allowing them to move freely while the patient breathes. If the layer of lubrication is reduced or disappears because of inflammation, friction builds up and the pleural membranes rub or grate against each other. The sound of a pleural rub can vary, but is often grating and squeaky. It is most noticeable when the patient breathes in or out. When asked to take deep breaths, the patient’s pleural rub can be especially noticeable.
Squeaky sounds in the chest can also be associated with a pericardial rub, where the layers of tissue that surround the heart become inflamed and rub against each other. To differentiate between the two noises, a doctor can ask a patient to hold a breath. If the sounds continue, they are being caused by a pericardial rub. If they stop, it means they are caused by inflammation in the pleural membranes.
Pleurisy or pleuritis, where the pleura become inflamed, is a common cause of a pleural rub. These sounds can also be associated with pneumothorax, pneumonia, and other conditions involving the lungs. The physician will also listen for breath sounds, take the patient’s temperature, listen to the heart, and perform other evaluations to gather data about the patient’s overall condition. Clusters of clinical signs paired with a pleural rub can point to a diagnosis, or a doctor may need to order medical tests and imaging studies.
Conditions involving inflamed pleura can be serious for a patient. Treatment options vary, depending on the cause, but can include anti-inflammatory drugs, medications like antibiotics to kill infectious organisms, and breathing treatments to help patients breathe more freely. It is important to receive treatment for breathing problems. If left untreated, the patient can rapidly deteriorate and be put at risk of serious complications. People with chronic breathing disorders like asthma are especially vulnerable to complications as a result of diseases involving the lungs and bronchial passages.