Week 1/2 - F - Allergic rhinitis - Pharmacology 4/ENT - symptoms, pathogenesis, causes, classification, diagnoses, treatment Flashcards
Rhinitis is a common and often debilitating disease involving acute, intermittent or chronic (persistent), inflammation of the nasal mucosa which is characterised by what symptoms?
Rhinitis caused by: Rhinorrhea - runny nose Sneezing Itching Nasal congestion and obstruction
Why is there nasal congestion and obstruction in rhinitis?
There is nasal congestion and obstruction due t swelling of the nasal mucosa largely due dilated blood vessels, also can be due to swelling of the turbinates due to irritation (nasal conchae)
There are many causes of rhinitis - this flashcard set shall focus mainly on allergic rhinitis Allergic rhinitis and allergic asthma are strongly linked and have many similarities What is the pathogenesis of the allergy mechansim? (why is IgE produced, what do they bind to, what is produced, what does this cause) - what does the delayed response contribute to
* Upon exposure to an allergen, atopic individuals have CD4+cells bind to APC - promote T helper cells producing allergen specific IgE * The IgE binds to receptors on basophils & mast cells * On re-exposure to allergen, degranulation causes the release of eg histamine, CystLT causing ACUTE itching, sneezing, rhinorrhea, nasal congestion DELAYED response caused by recruitment of lymphocyte and eosinophils contributes to nasal congestion and obstruction
What interleukin released from the Th2 cells prmotes B cell maturation into allergen specific IgE? What interleukin released from the Th2 cells prmotes esoiniphil differentiation and activation? This is the same for allergic asthma and allergic rhinitis
IL-4 released from the Th2 help promote B cells maturation into allergen specific IgE and help bind IgE to mast cells IL-5 released from Tcells promotes eosinophil differentiation and activation for delayed phase
What is non-allergic rhinitis? What are some causes?
This is any rhinitis, acute or chronic, that does not involve IgE mediate response Many causes eg Infection - mainly viral Occupational exposure to chemical irritants Medications Hormonal imbalance eg pregnancy
Allergic rhinitis can be classified as intermittent (seasonal) or persistent (perennial) by the ARIA (Allergic Rhinitis and its Impact on Asthma) classification What are common allergens that can cause allergic rhinitis? State which would classify as perennial or seasonal
House dust mite (HDM) faces and pet hair - usually cause perennial allergies Pollen of grasses, trees and weeds - usually cause seasonal allergies
ARIA classification allows you to classify allergic rhinits as intermittent or persistent State the factors for these classifications
Intermittent allergic rhinitis * Symptoms less than 4 days per week * or * Symptoms for less than 4 weeks Persitent allergic rhinitis * Symptoms greater than 4 days per week * or * Symptoms persistent for greater than 4 weeks
Intermittent allergic rhinitis - less than 4 days/week or less than 4 weeks Persistent allergic rhinitis - greater than 4 days/week or greater than 4 weeks Now we classify as mild or moderate/severe How is this done?
Mild - normal sleep and no impairment on quality of life or function Moderate/severe - one or more of the following Abnormal sleep Impacts quality of life or function eg missing work/school, daily exercise/performance, troublesome symptoms
The diagnosis of allergic rhinitis can often be made clinically and a theraputic trial of meds to confirm Should tests be carried out, what would they be?
Allergy testing may involve skin prick testing Serum testing may be used when skin prick testing is not possible, or skin prick testing taken with the clinical history give equivocal (ambiguous) results. - measuring the levels of serum-specific immunoglobulin (Ig) E to allergens such as house dust mites, pollen, and animal dander (radioallergosorbent test [RAST])
Once the diagnosis is confirmed, either clinically or after skin prick testing (or radioallergosorbent testing (RAST)), treatment! What is the non-pharmacological treatment advise given?
AVOIDANCE -Wash sheets at 60 - Remove carpets - Damp dusting - Ideally stay away from the pets - Avoid pollenated areas
What are the pharmacological step 1 treatments provided to for patients and how long are they continued for to see results? * Mild intermittent, or mild persistent symptoms * Moderate-to-severe symptoms
* Mild intermittent, or mild persistent symptoms - prescribe an antihistamine nasal spray (H1-receptor antagonist) or second generation non sedating oral antihistamine (loratadine/cetirizine) * Moderate-to-severe symptoms - prescribe an * antihistamine nasal spray + intransal steroid spray (eg fluticasone or mometasone) * or oral antihistamine + intransal steroid spray
Why are intranasal antihistamines preferred to oral? What is the name of the intranasal antihistamine?
Advise that intranasal antihistamines (azelastine) have a faster onset of action and are more effective than oral preparations
If step 1 treatment fails to resolve symptoms and the patient has a history of asthma, what can be considered for treatment?
Can try giving the patient a Cysteinyl-Leukotriene 1 receptor antagonists eg monteleukast or zafirlukast
If the patients symptoms remain persistent and severe, what options can be given?
If the person has severe, uncontrolled symptoms that are significantly affecting quality of life, consider prescribing a short course of oral corticosteroids to provide rapid symptom relief Specialist immunotherapy may be appropriate for people with symptoms on allergen exposure, objective confirmation of IgE sensitivity, and persistent symptoms
What are the immunotherapy routes of administration and how long is it continued for? Name a drug option that can be given?
Immunotherapy aim at exposing the person to increasing amounts of the specific allergen to induced clinical and immunological tolerance - treatment is sublingual or subcut and is continued for up to 3 years Immunotherapy is the only treatment that can modify disease progression, with long-term remission possible following the end of treatment.
