Diagnosis of Hay Fever
Accurate diagnosis of hay fever is essential for effective treatment and long-term symptom control. A proper diagnosis of hay fever helps distinguish allergic rhinitis from other conditions with similar symptoms such as viral infections, sinusitis, or non-allergic rhinitis. Identifying the specific allergens responsible for the reaction allows for personalised treatment plans, improved outcomes, and reduced risk of complications such as asthma exacerbation or chronic sinus issues.
Diagnosis typically begins with a detailed medical history and symptom review. A healthcare provider will ask about the timing, frequency, and severity of symptoms. Key indicators include sneezing, nasal congestion, runny nose, itchy eyes, throat irritation, postnasal drip, and coughing. Symptoms that worsen during certain seasons or when exposed to pets, dust, or mould often suggest allergic rhinitis.
The healthcare professional may also inquire about family history of allergies, the presence of eczema or asthma, and environmental exposures. This helps assess whether the individual is likely to have an atopic predisposition. Distinguishing between seasonal and perennial hay fever is important for guiding treatment. Seasonal hay fever typically flares up during specific times of the year, while perennial hay fever persists year-round due to indoor allergens.
Diagnosis of Hay Fever
Physical examination supports the diagnostic process. Common findings include swollen or pale nasal turbinates (internal nasal structures), clear nasal discharge, and red or watery eyes. Children may display signs such as allergic shiners (dark circles under the eyes), nasal crease (a line across the bridge of the nose from frequent rubbing), and mouth breathing.
Allergy testing confirms the diagnosis and identifies specific allergens. Skin prick testing is the most common method. A small amount of potential allergens is applied to the skin, and the area is pricked lightly. If a raised bump (wheal) forms, the person is allergic to that substance. Blood tests such as specific IgE testing (RAST or ImmunoCAP) can also detect allergen-specific antibodies, particularly useful for people with skin conditions or those unable to stop antihistamines before testing.
In some cases, nasal smears may be used to examine the type of cells present in nasal secretions. Eosinophils—a type of white blood cell—in high quantities indicate an allergic response. While not commonly done, this can help distinguish allergic rhinitis from viral or bacterial conditions.
Diagnosis of Hay Fever
Differential diagnosis is critical. Many upper respiratory conditions mimic hay fever. Chronic sinusitis may cause similar symptoms but is usually associated with facial pain, purulent nasal discharge, and poor response to antihistamines. Nasal polyps, medication-induced rhinitis, and non-allergic rhinitis with eosinophilia syndrome (NARES) must also be ruled out.
Ultimately, a thorough and accurate diagnosis of hay fever ensures that treatment targets the correct cause. Without proper diagnosis, individuals may use inappropriate treatments that fail to relieve symptoms or cause unnecessary side effects. As allergen exposure continues year after year, untreated hay fever can worsen over time, reinforcing the need for early and precise evaluation.
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