What Are the Causes of a Dry Cough?

Dry cough refers to a cough without sputum; Dry cough is one of the common symptoms of clinical lung diseases, and the cause is complicated.

Basic Information

English name: dry cough
Visiting department: Respiratory Medicine

Common causes: Infection, inflammation, allergy, reflux, etc.
Common symptoms: No or little sputum

Causes of dry cough and common diseases

Dry cough can be caused by lesions in different parts such as the nose, trachea, lungs, stomach, and esophagus. The causes are also diverse. Infections, inflammation, allergies, reflux, etc. can cause cough. A cough that lasts less than 3 weeks becomes an acute cough. The most common cause is a common cold. Other common causes include acute bronchitis, acute sinusitis, allergic rhinitis, acute episodes of chronic bronchitis, and bronchial asthma. A cough that lasts 3 to 8 weeks is called subacute cough. Patients should go to the hospital to check for lung diseases. Common causes include cough after a cold (also known as cough after infection), upper airway cough syndrome, and bronchial asthma. Unexplained cough that lasts more than 8 weeks is called chronic cough, and most chronic coughs (91% to 94%) are caused by the following four reasons: upper airway cough syndrome, cough variant asthma, and gastroesophageal reflux And chronic bronchitis, and in patients who do not smoke, do not take angiotensin-converting enzyme inhibitor (ACEI) drugs, and have normal chest imaging, almost all are caused by the first three diseases.

Differential diagnosis of dry cough

Pharyngitis

Chronic pharyngitis is a common pharyngeal disease, and its prominent symptom is irritating dry cough. Patients with pruritus and discomfort feel often cleared of dry coughs of the pharynx, and the symptoms are more pronounced during speech. The symptoms can be relieved after drinking water or after swallowing. Most are secondary to infectious lesions of the upper respiratory tract, allergic rhinitis, gastroesophageal reflux, or frequent smoking, and are more common among alcoholics and those exposed to certain harmful dust or gases. Examination of the pharynx shows congestion of the pharynx. Many dilated capillaries and a small number of lymphoid follicles can be seen on the mucosal surface of the posterior pharynx. The mucosa of the posterior pharynx and some exposed to harmful dust or gas are more common.

Laryngitis

The main symptom is hoarseness, which often occurs intermittently in the early stage, and often occurs when there is a lot of pronunciation. If the disease worsens, hoarseness can continue, but it is rare that no one has aphasia. The patient has a dry cough to reduce symptoms. Direct laryngomucosal examination. In patients with chronic simple laryngitis, the larynx mucosa is congested, the vocal cords are tarnished, there are dilated blood vessels distributed, and mucus secretions are increased. When the disease worsens and develops into chronic proliferative laryngitis, the mucosa Significant thickening is dark red, and the edges are hypertrophic with rounded marks. The pronunciation is often incomplete and the laryngeal zone is often thickened by compensatory activities. Chronic atrophic laryngitis is rare. Yellow-green The crusts have a burning or sore throat.

Dry cough check

The laboratory examination must be summarized and analyzed based on the objective materials of the medical history and physical examination, from which the possibility of several diagnoses is proposed, and then the actual examination room is used to confirm the diagnosis. Therefore, in view of dry cough and its associated symptoms, blood tests, lung X-rays, and laryngoscopes can be performed.