diease

Hay Fever


Hay Fever overview and Definition

Hay fever is an allergic reactions to certain materials.

Common triggers include pollen, ragweed, and cats.

It is also called as allergic rhinitis, there are two types: seasonal, which happens only during the time of year in which certain plants pollinate, and perennial, which happens year-round.

 

The  term Rhinitis refers to the inflammation of the inner lining of the nose. Hay fever occurs more than 4 weeks.


Pathophysiology

Hay fever is described as an acute  infection which shows inflammation in the pulmonary airway and bronchial hyperresponsiveness to an allergen resulting in asthmatic condition .inflammatory cells are accumulated in respiratory bronchioles.

Physiologically, allergen inhaled results in provocation of the inflammatory system of the respiratory system resulting in increased secreation of inflammatory mediators such as methacalmine and histamine. Release of histamine from the mast cells results in activation of the prostaglandins and leukotrienes.In addition to that cytokines are also released from the mast cells which leads to Increased vascular permeability, wheezing and bronchospasm.Triggering factors that results in  blockage of the pulmonary airway include cold air, exercise, viral upper respiratory infection, cigarette smoke, and respiratory allergens. Bronchial provocation with allergen induces a prompt early phase immunoglobulin E (IgE)-mediated decrease in bronchial airflow. Initially there is an increase in the leukocyte count in the pulmonary ares with help of CD4+ cells. The activated T-lymphocytes also direct the release of inflammatory mediators from eosinophils, mast cells, and lymphocytes. The cross-linkage of two IgE molecules by allergen causes mast cells to degranulate, releasing histamine, leukotrienes, and other mediators that perpetuate the airway inflammation. Histolopathology of the bronchial airway might shows  an inflammatory infiltrate such as mast cells, neutrophils, lymphocutes.


Clinical signs & symptoms

Nasal congestion

Post Nasal drip

Sneezing

Itching in eyes, nose and throat

cough

Difficulty breathing, cough.

Swelling of your face, throat or mouth tissue.

Wheezing or difficulty swallowing.

Restlessness and anxiety.

Loss of smell

Feeling of tightedness in the chest


Differential Diagnosis

A nasal endoscopy:

It is the instrument where a thin tube with a light source and visualizing unit at one end (ebdoscope) is inserted up to your nose so the physician can view the internal structure of nose clearly

A nasal inspiratory flow test:

A small device is placed over the mouth and nose to measure the air flow when you inhale the air through the nose.

Spirometry:

It  is a type of lung function test that measures how hard a person can blow air out of their lungs. It can determine the level of obstruction in the airway. The test is performed using a machine called a spirometer


Prognosis

 

The hay fever shows good prognosis but it might make day to day life little difficult.

Try to avoid triggering factors

 


Prevention

Stay away from the triggering factors

If any surgical correction is indicated do it early

Follow healthy lifestyle

Use a vacuum cleaner fitted with a high efficiency particulate air such as HEPA filter- it can remove more dust than ordinary vacuum cleaners.

Intake of vitamin c and zinc complements to boost the immunity.