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Eyes, ears, nose, and throat
Age-related macular degeneration
Bitemporal hemianopsia
Cataract
Color blindness
Cortical blindness
Diabetic retinopathy
Glaucoma
Hemianopsia
Homonymous hemianopsia
Retinal detachment
Neonatal conjunctivitis
Retinoblastoma
Retinopathy of prematurity
Corneal ulcer
Periorbital cellulitis
Uveitis
Keratitis
Orbital cellulitis
Hordeolum (stye)
Conjunctivitis
Neonatal conjunctivitis
Allergic rhinitis
Choanal atresia
Nasal polyps
Nasopharyngeal carcinoma
Thyroglossal duct cyst
Thyroid cancer
Hyperparathyroidism
Hypoparathyroidism
Eye conditions: Inflammation, infections and trauma: Pathology review
Eye conditions: Refractive errors, lens disorders and glaucoma: Pathology review
Eye conditions: Retinal disorders: Pathology review
Nasal, oral and pharyngeal diseases: Pathology review
Parathyroid disorders and calcium imbalance: Pathology review
Thyroid nodules and thyroid cancer: Pathology review
Vertigo: Pathology review
Allergic rhinitis
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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.
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