Seasonal Allergic Rhinitis (SAR)

In most parts of the developed world, there are three distinct times of the year in which patients with SAR may become symptomatic. These three times of symptom expression correspond to the periods at which various plant families pollinate, and can broadly be correlated with the spring, summer, and fall seasons. As a general rule, in more temperate climates these pollen seasons are relatively distinct, with tree pollen commonly present in the spring, grass pollen in the summer, and weed pollen in the fall. In addition, mold spores are often present in warmer weather, and can be present for much of the year in warmer and more humid climates.

Understanding the seasonality of SAR and geographic variations in the climate and expression of various pollens is an important tool for clinicians in treating patients with SAR. Since there is wide variability in the type of plants present in various climates and geographic locations, there is a corresponding variation in the types of pollens present. Furthermore, not all pollens stimulate SAR with the same degree of robustness. It is important for clinicians to be familiar with these local variations in planning therapy for their patients.

Perennial Allergic Rhinitis (PAR)

Patients with PAR tend to express nasal symptoms throughout most of the year, since the antigens to which they are reactive are present to some degree in the environment at all times. There can be some waxing and waning of the symptoms of PAR, both with concurrent seasonal triggers in patients with coexistent seasonal sensitivities, and with normal variations in the presence of and exposure to these antigens. For example, levels of indoor antigen often rise in the winter months, when patients will keep their windows closed and their houses tighter to preserve warmth in the home. In addition, patients may be exposed to antigens such as animal dander in a variable manner, as when visiting a relative who owns a a pet.

ARIA Classification of Allergic Rhinitis

While most of the literature on the diagnosis and treatment of allergic rhinitis has utilized this dichotomous classification based on seasonality of symptoms, expert opinion has recently suggested a new system for the classification of AR. This approach, which is based upon the chronicity and severity of symptoms of AR, was presented through a report entitled the ARIA Guidelines (Allergic Rhinitis and Its Impact on Asthma).³ The ARIA report suggests that a similar system should be used for the classification of allergic rhinitis to that used in classifying asthma.

The ARIA approach has four diagnostic categories that are used to classify the severity and chronicity of symptoms: (1) mild intermittent AR; (2) moderate-severe intermittent AR; (3) mild persistent AR; and (4) moderate-severe persistent AR (Figure 3.1). In this system, chronicity is divided into two categories: intermittent and persistent. Intermittent AR is defined as a symptomatic period lasting less than 4 days a week or less than 4 weeks a year. Persistent AR is defined as symptomatic periods lasting more than 4 days a week and occurring more than 4 weeks a year. In classifying the severity of rhinitis, the ARIA system defines two levels based upon the clinician’s assessment of the impact of rhinitis symptoms on daily function, sleep, or quality of life. Mild disease is characterized by symptoms that are bothersome to the patient, but do not cause significant impact on sleep, daily function, or quality of life. Moderate-severe disease differs from mild disease, in that it is characterized by symptoms that interfere with daytime function, adversely impact sleep quality or duration, or cause a decrease in global or disease-specific quality of life. Based upon an evaluation of severity and chronicity, the ARIA guidelines suggest a pattern of pharmacologic and nonpharmacologic interventions.

Figure 3.1 ARIA guidelines for classification of allergic rhinitis.

(Reproduced with permission from Bousquet J, et al. Allergy 2002;57:841–855; Blackwell Publishing.)

Irritative-toxic (Occupational) Rhinitis

Bachert described irritative-toxic rhinitis as rhinitis related to exposure to airborne irritants or toxic agents, such as chemicals, solvents, dyes, inks, and tobacco smoke. These irritative agents cause direct irritation of the nasal mucosa.

Hormonal Rhinitis

Hormonal influences are commonly associated with rhinitis. For example, nasal congestion is common during pregnancy, related to increased levels of various hormones.

Drug-induced Rhinitis

Bachert notes that many medications can affect nasal physiology. Many classes of medications, including angiotensin-converting enzyme (ACE) inhibitors, beta-blockers and other antihypertensive agents, oral contraceptives, psychotropic medications, topical nasal decongestants, nonsteroidal anti-inflammatory medications, and phospodiasterase type-5 inhibitors (PDE-5) have been shown to have effects on the nose (Box 3.2).

Idiopathic (Vasomotor) Rhinitis

Vasomotor rhinitis is a common nonimmune condition associated with copious clear rhinorrhea and intermittent congestion. The etiology is difficult to determine, but appears to be associated with environmental irritants, changes in atmospheric conditions, and odors or aromas. It appears to be more prevalent in older than in younger adults or children

Nonallergic Rhinitis with Eosinophilia (NARES)

Patients with NARES present with paroxysmal sneezing episodes, profuse watery rhinorrhea, nasal pruritis, nasal congestion, and hyposmia/anosmia. In contrast to allergic rhinitis patients, however, these patients fail to demonstrate any evidence for allergy on testing, yet have numerous eosinophils on nasal smears.⁶ Although its etiology is unknown, NARES shares clinical characteristics with Samter’s triad (aspirin sensitivity, asthma, and nasal polyposis), and may reflect a variant of that disease.

Overview

As noted above, rhinitis can be defined as an inflammatory or irritative disorder of the nasal membranes. Rhinitis presents with a pattern of symptoms that usually includes sneezing, nasal itching, rhinorrhea, and nasal congestion.⁷ In addition, patients with rhinitis will often complain of changes in the sense of smell, facial pressure or fullness, headache, and aural blockage. During periods of increased symptoms, patient with rhinitis experience a significant impact on both function and quality of life.

While nasal symptoms of rhinitis can be bothersome to patients and significantly interfere with normal function, the comorbidities of rhinitis can be quite serious and even life-threatening. Rhinitis represents inflammation in one part of the respiratory system, and can be associated with other common and serious respiratory illnesses such as rhinosinusitis and asthma.⁸ In fact, among patients with asthma, the prevalence of rhinitis in that population approaches 90%.⁹ In addition, rhinitis appears to play a role in the severity of symptoms among individuals with obstructive sleep apnea.¹⁰ Furthermore, the treatment of patients with chronic rhinosinusitis is often less successful among patients with allergic rhinitis than it is among their nonallergic counterparts. Because of its functional impairment and its serious comorbidities, rhinitis is therefore not a trivial disease, but one that can have serious medical and functional consequences.

Burden of rhinitis

The economic impact of rhinitis is significant. Direct costs annually attributable to the treatment of allergic rhinitis alone were estimated in 2003 to range between US$2 and 5 billion.¹¹ In addition, the indirect costs of AR significantly contribute to the economic burden of the disease, with an estimated US$5–10 billion annually attributable to the morbidity of this common disease.¹¹ In another recent estimate, over US$6 billion was outlayed specifically for prescription medications used for treating the symptoms of allergic rhinitis.¹² Worldwide treatment of rhinitis would certainly account for a significant increment in these US figures.

In addition to the direct and indirect financial costs of allergic and nonallergic rhinitis, quality of life, daytime function, and sleep are frequently compromised among patients, not only by the disease states but also by treatments whose adverse effects further adversely impact function. Patients with allergic and nonallergic rhinitis experience a wide range of cognitive and social issues that can be disruptive in their daily activities and interpersonal relationships. Fatigue, confusion, distractibility and other cognitive symptoms are common among patients with rhinitis, and can be worsened by treatment with pharmacologic agents such as sedating antihistamines. Among children with allergic rhinitis similar effects can be seen, resulting in decrements in learning and attention in the classroom.¹³ In addition, patients with AR experience disruption in normal patterns of sleep, which can contribute to daytime symptoms.¹⁴

Prevalence of Rhinitis

Allergic and nonallergic rhinitis are common illnesses. Prevalence studies worldwide suggest that the rates of AR within the population vary between 10% and 20%.^15,16 It has been reported that 58 million Americans annually experience symptoms of allergic rhinitis, while 19 million Americans experience symptoms of nonallergic rhinitis.¹⁵ As was noted earlier, many patients have both nonallergic and allergic triggers for their symptoms. This mixed rhinitis can occur in up to 44% of patients with AR.¹⁵

In addition to these absolute values, there is evidence that the prevalence of AR is increasing. Several studies have shown that the rates of AR have increased at least twofold over the past two decades.^17,18 While several hypotheses have been suggested to explain this increasing prevalence, the reasons for this steady increase remain speculative.

History

The evaluation of the patient with symptoms of rhinitis in large part depends on a thorough and careful history. Patients with both allergic and nonallergic rhinitis will present with characteristic symptoms that can be elicited through the history. In addition, the patient’s history can often distinguish AR from nonallergic rhinitis (Table 3.1).

Since allergic rhinitis usually has its onset in childhood, the majority of patients with AR will report a history of atopic symptoms beginning early in life. While rhinitis may not have been present in childhood, other atopic diseases such as asthma and eczema may have been present. In addition, patients may have experienced other upper respiratory diseases such as recurrent otitis media or rhinosinusitis. The age of onset is therefore an important factor to assess in the patient’s history.

In addition to age of onset, AR is a disease with a strong genetic component. It is common for patients with AR to have one or both parents who have a history of AR specifically or other atopic diseases. While the absence of a family history does not exclude a diagnosis of AR, it is less likely to occur among patients without a clear family history of atopic disease.

While not all patients with AR complain of seasonal triggers or fluctuations related to time of the year, seasonal variability of the patient’s nasal symptoms is also important to assess. The symptoms of SAR demonstrate a clear relationship with the increase of pollen in the environment during discrete seasons of the year. This variability of symptoms is an important component of the history among patients with rhinitis, and suggests a diagnosis of SAR. Patients with PAR may also have a seasonal worsening of symptoms, but will have significant symptoms between traditional pollen seasons. Many patients with AR will present with complaints characteristic of both SAR and PAR.

Many patients with SAR and PAR will be able to identify discrete exposures that elicit the onset of symptoms. They have learned that avoidance of these factors will decrease symptoms while exposure often brings about a prominent expression of symptoms. Not all patients have awareness of these discrete triggers, however. In taking the patient’s history, the clinician should determine if the patient is aware of any discrete symptomatic triggers that will predictably create symptoms. While patients with nonallergic rhinitis will also note specific triggering stimuli that cause symptoms, these triggers are nonimmune in nature, and include factors such as tobacco smoke, scents, paints, colognes, and similar irritants. Triggers for patients with AR, by contrast, are seasonal and perennial allergens.

Physical Examination

The physical examination of the patient with symptoms of rhinitis involves not only a careful evaluation of the nose itself, but also a comprehensive evaluation of the head, neck, and chest as well. The physical examination begins with an inspection of the face. The clinician will examine the face for external signs suggesting nasal inflammation. These signs include facial puffiness, edema, facial asymmetry, or infraorbital discoloration (Figure 3.3). The eyes are examined for evidence of conjunctival injection, irritation or erythema. Infraorbital darkening of the skin implies venous stasis due to nasal congestion. Allergic patients often demonstrate fine creases in the eyelids, noted as Dennie’s lines. These fine creases occur due to spasms of Mueller’s muscles, and are often seen in children with AR.

Figure 3.3 Facial appearance of a child with rhinitis.

(Reproduced with permission from Zitelli BJ. Atlas of pediatric physical diagnosis, 3rd edn, published by Mosby, 1997.)

Stay updated, free articles. Join our Telegram channel

Join