00:00 / 00:00
Respiratory system
Acute respiratory distress syndrome
Cyanide poisoning
Decompression sickness
Methemoglobinemia
Pulmonary changes at high altitude and altitude sickness
Congenital pulmonary airway malformation
Pulmonary hypoplasia
Tracheoesophageal fistula
Pneumonia
Lung cancer
Pancoast tumor
Superior vena cava syndrome
Apnea of prematurity
Meconium aspiration syndrome
Neonatal respiratory distress syndrome
Sudden infant death syndrome
Transient tachypnea of the newborn
Alpha 1-antitrypsin deficiency
Asthma
Bronchiectasis
Chronic bronchitis
Cystic fibrosis
Emphysema
Hypersensitivity pneumonitis
Idiopathic pulmonary fibrosis
Restrictive lung diseases
Sarcoidosis
Apnea, hypoventilation and pulmonary hypertension: Pathology review
Cystic fibrosis: Pathology review
Deep vein thrombosis and pulmonary embolism: Pathology review
Lung cancer and mesothelioma: Pathology review
Obstructive lung diseases: Pathology review
Pleural effusion, pneumothorax, hemothorax and atelectasis: Pathology review
Pneumonia: Pathology review
Respiratory distress syndrome: Pathology review
Restrictive lung diseases: Pathology review
Tuberculosis: Pathology review
Allergic rhinitis
0 / 11 complete
of complete
2022
2021
2020
2019
2018
2017
2016
phenylephrine for p. 243
type I hypersensitivity p. 110
“Rhin” refers to the nose and “itis” refers to inflammation, so rhinitis is nasal inflammation.
Allergic rhinitis is also called hay fever, and it’s typically caused by allergens like hay, as well as pollen, dust, animal hair, or mold spores.
When the main trigger is pollinating plants, allergic rhinitis will flare up at specific times of the year.
Allergic rhinitis is a type 1 hypersensitivity reaction, which is a type of allergic reaction that starts with exposure to an environmental allergen.
So - let’s say that a bit of pollen enters the nose. It can get picked up by a dendritic cell which is a type of immune cell that gobbles up foreign particles and presents it to a nearby lymphocyte called a T cell.
If the T cell gets activated, it kicks into action, producing cytokines which helps to get other immune cells involved.
The exact type of T cell determines the type of immune response, and in allergic rhinitis there’s a bit of a T cell imbalance.
There are too many T cells that, when activated, stimulate B cells, another group of lymphocytes, to produce IgE antibodies.
Those IgE antibodies get released into the bloodstream and bind to mast cells, which are immune cells in the tissue that carry within themselves a load histamine.
Once bound by IgE the mast cells are “primed”, meaning if pollen enters the body again in the future, those mast cells degranulate and release their histamine into the local tissue.
Copyright © 2023 Elsevier, its licensors, and contributors. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
Cookies are used by this site.
USMLE® is a joint program of the Federation of State Medical Boards (FSMB) and the National Board of Medical Examiners (NBME). COMLEX-USA® is a registered trademark of The National Board of Osteopathic Medical Examiners, Inc. NCLEX-RN® is a registered trademark of the National Council of State Boards of Nursing, Inc. Test names and other trademarks are the property of the respective trademark holders. None of the trademark holders are endorsed by nor affiliated with Osmosis or this website.