Asthma, characterized by shortness of breath, chest tightness, is one of the chronic of lung with the wheezing due to airflow obstruction and bronchospasm with episodes of attacks seen mostly in night and early morning time. It mostly affects the school aged children and is increasing day by day. According to WHO (world health organization) 235 million people suffer from asthma. As it mention above the asthma is chronic condition so there is episode of attack is present.
It is classified as mild, moderate and severe asthma. Mild is attack usually I < 2 time per week. Moderate is daily and continuous multiple episodes.
Causes :
Most common causes of asthma are listed as below
1) Environmental factors:
Allergens:
It includes allergies and air pollution and other environmental factors: indoor allergens like household dust mites in bedding, carpets and stuffed furniture, pollution and cockroaches, animal dander whereas outdoor allergens are pollen and mounds. Besides person can also be allergic to fruits like apple, perfume
Tobacco smoke:
Smoking during pregnancy and after delivery is the main cause of asthma that not only developed asthma and also increase the risk and severity of asthma. Chemical irritants, air pollution, cotton factory worker are at high risk of developing asthma and severity increase to those who had already got asthma
2) Drugs
Certain drugs also induce asthma. Acetaminophen (Paracetamol) can induce asthma. But this side effect of Paracetamol is not seen usually. Perhaps if a mother is taking Paracetamol during pregnancy the risk of asthma is increase. Use of aspirin can also cause asthma. Use of beta blocker such as levatol, propranolol can cause asthma if a person who has risk of developing asthma. Early Use of antibiotics in life has been linked to the development of asthma.
3) Virus and Bacteria toxin
Respiratory syncytial virus (RSV) and rhinovirus. Cause asthma. In the similar way some bacterial toxin can also cause asthma in adult but in children
4) Genetic factor s
Family history is most important cause of asthma. If a mother or father or any other family member had history of asthma then the risk of asthma in child is increase. Most of the case of asthma during childhood has family history of asthma. Over 100 genes are associated with asthma also some genes cause asthma if they mixed with environmental factors or bacterial toxin. 25 genes had been associated with asthma in six or more separate populations, including GSTM1, IL10, CTLA-4, SPINK5, LTC4S, IL4R and ADAM33, among others.
5) Medical conditions
Hypersensitive reaction type 1, Rhinitis especially allergic Rhinitis is most commonly associated with asthma.
Â
PATHOPHYISOLOGY OF ASTHMA
As asthma is chronic inflammatory condition, inflammation of respiratory tract occurs which then cause contraction of smooth muscles and narrowing the airway that ultimately produce wheezing. This inflammation is then mediated by eosinophil and the further thickening of airway will be there with increase mucus secretion. T lymphocytes, macrophages, and neutrophils are also play important role in inflammation of airway .Other components of the immune system including such as cytokines, chemokines, histamine, and leukotrienes can also increase the thickness of smooth muscle cells too
 Other similar conditions like asthmas
These are the sum of other conditions that can mimic the asthma.
- Bronchiolitis
- Emphysema
- Croup
- Foreign Body aspiration
- Chronic obstructive pulmonary disease (COPD)
DIAGNOSES OF ASTHMA
Diagnosis can be done by
Family history,
Spirometry test
- ask patient to take deep breath as possible as they can and hold it for least for six seconds for adult and 3 second for children under 10 year of age and then put nose clip in order to prevent the air out
- Put spirometer on mouth around the lip and exhaled out the air as fast and hardly as u can and stop until your health taker say.
- Repeat this process 3 times for accurate result.
patient doing spirometry test
Methcholine test
Inhaled methacholine that cause narrow of airway and there will be wheezing sound.
TREATMENT
Life style modification.
Avoid the causative agents like smocking, pats, aspirin inducing asthma, exposure of allergens (dust, perfumed, dust). Use mask to prevent from air pollution
Taking caffeine can help for bronchio-dialator as well
MEDICATION:
Corticosteroids, beta 2 adergenic that prevent bronchospasm like salbutamol , salmeterol and formoterol , Leukotriene receptor blocker such as montelukast and zafirlukast ,Mast cell stabilizers such as cromolyn sodium,Bronchodilators like Theophylline are generally used medications. Cortocosteriods along with long and short acting anti bronchospasmtic medication are used inhaler for the prompt action. Beside if have severe asthma, nebulization with salbutamol, atropine and theophylline or normal saline (NaCl) are also used. If the patient is worsening and no response to the medication then may need mechanical ventilation.
References
CDC Asthma
Treatment Guidelines
Wiki Asthma
WebMed
Compiled by: zaara,Final Year MBBS medical student at Yangtze University,China