Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, coughing, chest tightness, and shortness of breath. These may occur a few times a day or a few times per week. Depending on the person, asthma symptoms may become worse at night or with exercise.
A cough is a sudden expulsion of air through the large breathing passages which can help clear them of fluids, irritants, foreign particles and microbes. As a protective reflex, coughing can be repetitive with the cough reflex following three phases: an inhalation, a forced exhalation against a closed glottis, and a violent release of air from the lungs following opening of the glottis, usually accompanied by a distinctive sound.
Sputum is mucus that is coughed up from the lower airways. In medicine, sputum samples are usually used for a naked eye examination, microbiological investigation of respiratory infections and cytological investigations of respiratory systems. It is crucial that the specimen does not include any mucoid material from the nose or oral cavity.
Eosinophils, sometimes called eosinophiles or, less commonly, acidophils, are a variety of white blood cells and one of the immune system components responsible for combating multicellular parasites and certain infections in vertebrates. Along with mast cells and basophils, they also control mechanisms associated with allergy and asthma. They are granulocytes that develop during hematopoiesis in the bone marrow before migrating into blood, after which they are terminally differentiated and do not multiply. They form about 2 to 3% of white blood cells in the body.
Acute bronchitis, also known as a chest cold, is short-term bronchitis – inflammation of the bronchi of the lungs. The most common symptom is a cough. Other symptoms include coughing up mucus, wheezing, shortness of breath, fever, and chest discomfort. The infection may last from a few to ten days. The cough may persist for several weeks afterward with the total duration of symptoms usually around three weeks. Some have symptoms for up to six weeks.
Bronchoconstriction is the constriction of the airways in the lungs due to the tightening of surrounding smooth muscle, with consequent coughing, wheezing, and shortness of breath.
Eosinophilic pneumonia is a disease in which an eosinophil, a type of white blood cell, accumulates in the lungs. These cells cause disruption of the normal air spaces (alveoli) where oxygen is extracted from the atmosphere. Several different kinds of eosinophilic pneumonia exist and can occur in any age group. The most common symptoms include cough, fever, difficulty breathing, and sweating at night. Eosinophilic pneumonia is diagnosed by a combination of characteristic symptoms, findings on a physical examination by a health provider, and the results of blood tests and X-rays. Prognosis is excellent once most eosinophilic pneumonia is recognized and treatment with corticosteroids is begun.
Acute severe asthma, also known as status asthmaticus, is an acute exacerbation of asthma that does not respond to standard treatments of bronchodilators (inhalers) and corticosteroids. Asthma is caused by multiple genes, some having protective effect, with each gene having its own tendency to be influenced by the environment although a genetic link leading to acute severe asthma is still unknown. Symptoms include chest tightness, rapidly progressive dyspnea, dry cough, use of accessory respiratory muscles, fast and/or labored breathing, and extreme wheezing. It is a life-threatening episode of airway obstruction and is considered a medical emergency. Complications include cardiac and/or respiratory arrest. The increasing prevalence of atopy and asthma remains unexplained but may be due to infection with respiratory viruses.
Eosinophilic esophagitis (EoE) is an allergic inflammatory condition of the esophagus that involves eosinophils, a type of white blood cell. In healthy individuals, the esophagus is typically devoid of eosinophils. In EoE, eosinophils migrate to the esophagus in large numbers. When a trigger food is eaten, the eosinophils contribute to tissue damage and inflammation. Symptoms include swallowing difficulty, food impaction, vomiting, and heartburn.
Reactive airway disease (RAD) is an informal label that physicians apply to patients with symptoms similar to those of asthma. An exact definition of the condition does not exist. Individuals who are typically labeled as having RAD generally have a history of wheezing, coughing, dyspnea, and production of sputum that may or may not be caused by asthma. Symptoms may also include, but are not limited to, coughing, shortness of breath, excess mucus in the bronchial tube, swollen mucous membrane in the bronchial tube, and/or hypersensitive bronchial tubes. Physicians most commonly label patients with RAD when they are hesitant about formally diagnosing a patient with asthma, which is most prevalent in the pediatric setting. While some physicians may use RAD and asthma synonymously, there is controversy over this usage.
Allergic bronchopulmonary aspergillosis (ABPA) is a condition characterised by an exaggerated response of the immune system to the fungus Aspergillus. It occurs most often in people with asthma or cystic fibrosis. Aspergillus spores are ubiquitous in soil and are commonly found in the sputum of healthy individuals. A. fumigatus is responsible for a spectrum of lung diseases known as aspergilloses.
Bronchitis is inflammation of the bronchi in the lungs that causes coughing. Bronchitis usually begins as an infection in the nose, ears, throat, or sinuses. The infection then makes its way down to the bronchi. Symptoms include coughing up sputum, wheezing, shortness of breath, and chest pain. Bronchitis can be acute or chronic.
Obstructive lung disease is a category of respiratory disease characterized by airway obstruction. Many obstructive diseases of the lung result from narrowing (obstruction) of the smaller bronchi and larger bronchioles, often because of excessive contraction of the smooth muscle itself. It is generally characterized by inflamed and easily collapsible airways, obstruction to airflow, problems exhaling, and frequent medical clinic visits and hospitalizations. Types of obstructive lung disease include; asthma, bronchiectasis, bronchitis and chronic obstructive pulmonary disease (COPD). Although COPD shares similar characteristics with all other obstructive lung diseases, such as the signs of coughing and wheezing, they are distinct conditions in terms of disease onset, frequency of symptoms, and reversibility of airway obstruction. Cystic fibrosis is also sometimes included in obstructive pulmonary disease.
In medicine, exhaled nitric oxide (eNO) can be measured in a breath test for asthma and other respiratory conditions characterized by airway inflammation. Nitric oxide (NO) is a gaseous molecule produced by certain cell types in an inflammatory response. The fraction of exhaled NO (FENO) is a promising biomarker for the diagnosis, follow-up and as a guide to therapy in adults and children with asthma. The breath test has recently become available in many well-equipped hospitals in developed countries, although its exact role remains unclear.
An acute exacerbation of chronic obstructive pulmonary disease, or acute exacerbations of chronic bronchitis (AECB), is a sudden worsening of chronic obstructive pulmonary disease (COPD) symptoms including shortness of breath, quantity and color of phlegm that typically lasts for several days.
Chronic obstructive pulmonary disease (COPD) is a type of progressive lung disease characterized by long-term respiratory symptoms and airflow limitation. The main symptoms of COPD include shortness of breath and a cough, which may or may not produce mucus. COPD progressively worsens, with everyday activities such as walking or dressing becoming difficult. While COPD is incurable, it is preventable and treatable. The two most common types of COPD are emphysema and chronic bronchitis and have been the two classic COPD phenotypes. Emphysema is defined as enlarged airspaces (alveoli) whose walls have broken down resulting in permanent damage to the lung tissue. Chronic bronchitis is defined as a productive cough that is present for at least three months each year for two years. Both of these conditions can exist without airflow limitation when they are not classed as COPD. Emphysema is just one of the structural abnormalities that can limit airflow and can exist without airflow limitation in a significant number of people. Chronic bronchitis does not always result in airflow limitation but in young adults who smoke the risk of developing COPD is high. Many definitions of COPD in the past included emphysema and chronic bronchitis, but these have never been included in GOLD report definitions. Emphysema and chronic bronchitis remain the predominant phenotypes of COPD but there is often overlap between them and a number of other phenotypes have also been described. COPD and asthma may coexist and converge in some individuals. COPD is associated with low-grade systemic inflammation.
Chronic cough is long-term coughing, sometimes defined as more than several weeks or months. Generally a cough lasting for more than eight weeks for an adult would meet the clinical definition of a chronic cough; and for children this threshold is lower. The term can be used to describe the different causes related to coughing, the three main ones being upper airway cough syndrome, asthma and gastroesophageal reflux disease. It occurs in the upper airway of the respiratory system. Generally, a cough lasts around one to two weeks; however, chronic cough can persist for an extended period of time defined as six weeks or longer. People with chronic cough often experience more than one cause present. Due to the nature of the syndrome, the treatments used are similar; however, there are a subsequent number of treatments available, and the clinical management of the patients remains a challenge.
Lirentelimab is a humanized nonfucosylated monoclonal antibody that targets sialic acid-binding Ig-like lectin 8 (SIGLEC8). In a randomized clinical trial, lirentelimab was found to improve eosinophil counts and symptoms in individuals with eosinophilic gastritis and duodenitis. Adverse reactions include infusion reactions, which are mild to moderate and typically occur following the first infusion.
Asthma triggers are factors or stimuli that provoke the exacerbation of asthma symptoms or increase the degree of airflow disruption, which can lead to an asthma attack. An asthma attack is characterized by an obstruction of the airway, hypersecretion of mucus and bronchoconstriction due to the contraction of smooth muscles around the respiratory tract. Its symptoms include a wide range of manifestations such as breathlessness, coughing, a tight chest and wheezing.
Asthma-Chronic Obstructive Pulmonary Disease (COPD) Overlap (ACO), also known as Asthma-COPD Overlap Syndrome (ACOS) is a chronic inflammatory, obstructive airway disease in which features of both asthma and COPD predominate. Asthma and COPD were once thought of as distinct entities, however in some, there are clinical features of both asthma and COPD with significant overlap in pathophysiology and symptom profile. It is unclear whether ACO is a separate disease entity or a clinical subtype of asthma and COPD. The pathogenesis of ACO is poorly understood, but it is thought to involve both type 2 inflammation as well as type 1 inflammation. The incidence and prevalence of ACO are not well known. The risk factors for ACO are also incompletely understood, but tobacco smoke is known to be a major risk factor.
