Antibiotics and asthma: a tricky tributary of the hygiene hypothesis

The human respiratory tract, comprising the upper and lower segments, serves as a critical interface with the external environment. The upper respiratory tract (URT)—including the nostrils, sinuses, pharynx, and oropharynx—is heavily colonized by microbes, while the lower respiratory tract (LRT), composed of the larynx, trachea, bronchi, and lungs, was long thought to be sterile. However, recent molecular studies have revealed that the lungs are not devoid of microbes but act more...

Asthma is a chronic inflammatory disorder of the airways characterized by variable airflow obstruction and heightened bronchial responsiveness to a wide range of triggers. The underlying inflammation leads to airway swelling, mucus hypersecretion, and smooth muscle constriction, all of which narrow the airway lumen and impede airflow. Clinically, asthma presents with recurrent episodes of wheezing, shortness of breath, chest tightness, and coughing, symptoms that typically vary in intensity and...

Asthma is a chronic respiratory ailment that requires careful management due to its varying symptoms and influencing factors. It is characterized by airway inflammation, bronchial hyperresponsiveness, and reversible airflow obstruction, leading to symptoms like wheezing, shortness of breath, chest tightness, and coughing. The symptom frequency and intensity may vary considerably over time. It is also linked to immune system responses to allergens and irritants, highlighting the complex...

Asthma is a chronic pulmonary condition involving inflammation of the airways, hyper-reactivity, and reversible obstruction of the airways. This condition can significantly impact a person's quality of life, making breathing difficult and leading to distressing symptoms.
Asthma is classified as allergic and non-allergic. Allergens such as dust mites, pollen, and pet dander trigger allergic asthma, while factors like cold air, intense emotions, or exercise can induce non-allergic asthma.

Asthma is a prevalent chronic respiratory condition marked by inflammation and hyperresponsiveness of the airways. Its pathophysiology involves complex interactions among inflammatory pathways, immune responses, and neural mechanisms.
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:

Leukotriene modifiers, or cysteinyl leukotriene receptor antagonists, are medications used to manage chronic asthma. These agents target specific inflammatory mediators produced during arachidonic acid metabolism, an essential process in generating inflammation in the body.
Leukotriene modifiers work through two distinct mechanisms: