Allergic rhinitis

What is asthma?

Up to 50 percent of patients with asthma have allergic rhinitis. In children, cough and wheeze are the most common symptoms and are often more prominent with exertion.

What is the epidemiology of allergic rhinitis?

Allergic rhinitis is common, affecting 10 to 30 percent of children and adults in the United States and other industrialized countries. The prevalence in the industrialized world is increasing, particularly in urban areas.

What conditions are associated with allergic rhinitis?

Allergic rhinitis occurs in association with a number of other disorders, including allergic conjunctivitis, acute or chronic sinusitis, asthma, and atopic dermatitis (eczema).

How does allergic rhinitis present clinically?

Allergic rhinitis presents with paroxysms of sneezing, rhinorrhea, nasal obstruction, and nasal itching. Postnasal drip, cough, irritability, and fatigue are other common symptoms.

What is late nasal reaction?

A late-phase nasal allergic reaction develops in approximately 50 percent of patients with seasonal rhinitis, which peaks at 6 to 12 hours after nasal allergen challenge. This secondary inflammatory response is thought to be important in establishing the chronicity of the disorder. During this later phase, symptoms may recur after a second release of mast cell mediators that is coincident with maximum mast cell cytokine production. The late-phase allergic reaction is associated with elevated levels of the same mediators noted in the immediate reaction, except that PGD2 is not detected.

What is the natural history of allergic rhinitis?

Allergic rhinitis typically requires a few years of allergen exposure to develop. Accordingly, it is uncommon in children under two years of age. If a very young child appears to have persistent nasal symptoms, other disorders should be considered. Sensitization to aeroallergens generally precedes the appearance of rhinitis symptoms. In children, sensitization and then clinical allergy develop first to allergens that are continually present in the environment (eg, dust mites or animal danders) and then to pollens and other seasonal allergens. After the age of two, the prevalence of allergic rhinitis steadily increases, demonstrating a bimodal peak in the early school and early adult years.

What is allergic rhinitis?

Allergic rhinitis, or allergic rhinosinusitis, is characterized by paroxysms of sneezing, rhinorrhea, and nasal obstruction, often accompanied by itching of the eyes, nose, and palate.

What is the treatment for severe allergic rhinitis in children under two years?

Changing to a glucocorticoid nasal spray is the next step for children with severe symptoms not responsive to the above measures.

What differential diagnoses should be considered when evaluating a patient for allergic rhinitis?

Children under two years of age: -Adenoidal hypertrophy -Acute or chronic sinusitis -Congenital abnormalities -Foreign bodies -Nasal polyps Older children and adults: -Acute infectious rhinitis -Chronic nonallergic rhinitis -Rhinitis medicamentosa -Rhinitis due to systemic medications -Atrophic rhinitis -Rhinitis associated with hormonal changes -Unilateral rhinitis or nasal polyps -Rhinitis with immunologic disorders

What is the treatment for persistent or moderate-to-severe allergic rhinitis in older children and adults?

Glucocorticoid nasal sprays are the most effective pharmacologic therapy for allergic rhinitis and are recommended by guidelines as the best single therapy for patients with persistent or moderate-to-severe symptoms, including seasonal symptoms. For patients with moderate-to-severe symptoms and/or in those who fail to respond adequately to initial therapy with glucocorticoid nasal sprays, a second agent can be added: -Antihistamine spray -Minimally sedating oral antihistamine -Minimally sedating oral antihistamine/decongestant combination

How does the oropharynx appear in allergic rhinitis?

Hyperplastic lymphoid tissue lining the posterior pharynx, which resembles cobblestones (a finding called "cobblestoning").

What are the two types of nasal reactions?

Immediate and late nasal reactions.

What is atopic dermatitis (eczema)?

In children, atopic dermatitis presents with intensely pruritic erythematous patches with papules and some crusting, usually affecting the face, scalp, extremities, or trunk, with sparing of the diaper areas.

What are common physical findings of allergic rhinitis?

Infraorbital edema and darkening due to subcutaneous venodilation, findings that are sometimes referred to as "allergic shiners". Accentuated lines or folds below the lower lids (Dennie-Morgan lines), which suggests concomitant allergic conjunctivitis. A transverse nasal crease caused by repeated rubbing and pushing the tip of the nose up with the hand (the "allergic salute"). "Allergic facies," which are typically seen in children with early-onset allergic rhinitis, consist of a highly arched palate, open mouth due to mouth breathing, and dental malocclusion.

What are patterns of symptoms in allergic rhinitis?

Intermittent - Symptoms are present less than four days per week or for less than four weeks. Persistent - Symptoms are present more than four days per week and for more than four weeks. Mild - None of the items listed below for "moderate-severe" are present. Moderate-severe - One or more of the following items is present: •Sleep disturbance •Impairment of school or work performance •Impairment of daily activities, leisure, and/or sport activities •Troublesome symptoms

What is allergen-specific testing?

It is not necessary to perform testing for allergen-specific IgE either with blood tests or skin testing before making the presumptive diagnosis of allergic rhinitis and initiating treatment. Primary care clinicians treat the majority of patients with allergic rhinitis and often initiate therapy empirically, identifying possible triggers only through the clinical history. This approach is adequate for many patients. Immediate hypersensitivity skin testing (prick skin tests) is a quick and cost-effective way to identify the presence of allergen-specific IgE.

What is sinusitis?

Nasal inflammation associated with allergic rhinitis can also cause obstruction of the sinus ostiomeatal complex, thereby predisposing to bacterial infection of the sinuses. Symptoms of bacterial sinusitis include nasal congestion, purulent rhinorrhea or postnasal drip, facial or dental pain, and cough. Purulent rhinorrhea, purulent postnasal drip, pain in a maxillary tooth or, in children, persistent cough, are the most useful predictors of bacterial sinusitis.

When should patients with allergic rhinitis be referred?

Patients whose symptoms are severe or refractory to therapy should be referred to an allergy specialist for a more definitive evaluation. Referral to an allergy or pulmonary specialist is also useful for patients with concomitant allergic rhinitis and asthma, and an otolaryngologist may be helpful in managing patients with recurrent episodes of sinusitis or otitis media.

What is the treatment for mild or episodic allergic rhinitis in older children and adults?

Patients with mild or episodic symptoms that are related to predictable allergen exposures (visiting a relative's house with a pet) can be managed with one of the following options: ●A second-generation oral antihistamine ●An antihistamine nasal spray (eg, azelastine or olopatadine) ●A glucocorticoid nasal spray (more effective than antihistamines) ●Cromolyn nasal spray administered regularly or as needed (ideally 30 minutes before an exposure).

What are laboratory findings in allergic rhinitis?

Routine laboratories are usually normal. Neither peripheral blood eosinophil counts nor total serum immunoglobulin E (IgE) levels (elevated in only 30 to 40 percent of patients) are sensitive enough to help diagnose allergic rhinitis.

What is seasonal allergic rhinitis?

Seasonal allergy rhinitis is usually caused by pollen from trees, grasses, and weeds. Depending upon the geographic area, pollination periods for certain types of plants are well known.

What are impacts of allergic rhinitis on quality of life/cognitive function?

Sleep-disturbed breathing is one of the most important sequelae of untreated allergic rhinitis. Fatigue and generalized malaise are common, although patients rarely report these symptoms directly. Allergic rhinitis is associated with a host of cognitive and psychiatric issues in children and adolescents, including attention deficit hyperactivity disorder, lower exam scores during peak pollen seasons, poor concentration, impaired athletic performance, and low self-esteem.

What is the treatment for allergic rhinitis in children under two years?

The development of allergic rhinitis requires repeated exposure to inhaled allergens and is therefore uncommon in children under two years of age. If a child under two years of age is determined to have allergic rhinitis after an evaluation for other causes, treatment options include the following: Cromolyn (sodium cromoglycate) nasal spray is available without a prescription and has essentially no adverse effects because it is not absorbed systemically. Minimally-sedating antihistamines (cetirizine, loratadine, and fexofenadine) are available in liquid formulations.

How is allergic rhinitis diagnosed?

The diagnosis of allergic rhinitis can be made on clinical grounds based upon the presence of characteristic symptoms (ie, paroxysms of sneezing, rhinorrhea, nasal obstruction, nasal itching, postnasal drip, cough, irritability, and fatigue), a suggestive clinical history (including the presence of risk factors), and supportive findings on physical examination. Allergy skin testing confirms that the patient is sensitized to aeroallergens, although it is not necessary for the initial diagnosis.

What are risk factors for allergic rhinitis?

The following are proposed or identified risk factors for allergic rhinitis: ●Family history of atopy (ie, the genetic predisposition to develop allergic diseases) ●Male sex ●Birth during the pollen season ●Firstborn status ●Early use of antibiotics ●Maternal smoking exposure in the first year of life ●Exposure to indoor allergens, such as dust mite allergen ●Serum immunoglobulin E (IgE) >100 international units/mL before age 6 ●Presence of allergen-specific IgE

What is the general management of allergic rhinitis?

The management of allergic rhinitis involves the following components: -Pharmacotherapy -Allergen avoidance -Allergen immunotherapy

How do the nasal turbinates appear in allergic rhinitis?

The nasal mucosa of patients with active allergic rhinitis frequently has a pale bluish hue or pallor along with turbinate edema Clear rhinorrhea may be visible anteriorly, or if the nasal passages are obstructed, rhinorrhea may be visible dripping down the posterior pharynx.

What is the physical examination for allergic rhinitis?

The nose, oropharynx, tympanic membranes, and eyes should be examined, as each of these structures may show findings of allergic rhinitis or associated disorders.

What is allergic conjunctivitis?

Up to 60 percent of patients with allergic rhinitis have concomitant allergic conjunctivitis. Allergic conjunctivitis presents with itching, tearing, conjunctival edema, hyperemia, watery discharge, burning, and photophobia. Eyelid edema is also common. Symptoms are usually bilateral.

What is the mechanism of upper airway allergic reactions?

Upon exposure to an allergen, atopic individuals respond by producing allergen-specific immunoglobulin E (IgE). These IgE antibodies bind to IgE receptors on mast cells in the respiratory mucosa and to basophils in the peripheral blood. When the same allergen is subsequently inhaled, the IgE antibodies are bridged on the cell surface by allergen, resulting in activation of the cell. Mast cells in the nasal tissues release preformed and granule-associated chemical mediators, which cause the symptoms of allergic rhinitis. Histamine is the most important preformed mediator in allergic rhinitis.

What is immediate nasal reaction?

Within seconds to minutes of allergen exposure, an immediate allergic response is observed, which peaks in 15 to 30 minutes. Sneezing correlates with the appearance of measurable histamine, the kininogen product tosyl-L-arginine methyl ester (TAME esterase), and prostaglandin D2 (PGD2) in nasal washes. The presence of histamine, tryptase, and PGD2 indicate the central role of the mast cell in the early response to allergen.