Spring sneezin’ season: Clarifying diagnoses for spring respiratory allergy symptoms

As winter respiratory viruses linger and spring aeroallergens begin to rise, primary care physicians face increasing diagnostic complexity in the exam room. During this seasonal transition, patients may cycle through multiple empiric treatments for weeks or months, contributing to persistent symptoms, cumulative inflammation and repeat visits with their primary care provider without getting to the root cause of their symptoms.

There is good news for physicians and patients: Early diagnostic clarification can help primary care physicians and other clinicians improve diagnostic accuracy, health care resource utilization and, most importantly, patient health outcomes during the seasonal shift from winter to spring.

As winter respiratory illnesses taper and spring allergies begin, why does this period create heightened diagnostic uncertainty for primary care physicians and patients?

The transition from late winter into early spring is a perfect overlap of respiratory triggers. During this time, viral infections are still circulating and causing airway inflammation, and outdoor respiratory allergens like tree pollens are beginning to rise.

Viral rhinitis, allergic rhinitis and nonallergic rhinitis share many of the same symptoms, like sneezing, rhinorrhea, nasal congestion, cough and postnasal drip, so it can be difficult to distinguish the root cause of patients’ symptoms.

For patients, especially those with no notable history of respiratory conditions, a sudden onset of symptoms may leave them feeling uncertain or scared about what they’re experiencing.

How have patterns of seasonal respiratory illnesses and allergies evolved in recent years? And why are these patterns important for physicians to be mindful of?

A review in Laryngoscope found that climate change is altering pollen seasons and concentrations, allergic rhinitis disease prevalence, allergy sensitization and allergic rhinitis symptom severity. Additionally, research suggests that climate change is altering the seasonality and geographic range of viral respiratory infections, with peaks shifting toward warmer seasons and epidemic dynamics becoming increasingly unpredictable.

These extended symptom seasons are only increasing the overlap between respiratory viruses and aeroallergen exposure, which includes inhaling airborne particles like pollen, mold, dust mites and pet dander, leading to increased disease burden.

When seasonal pollens are added into the mix this spring, they can layer on top of that perennial exposure. If a patient also recently had a viral infection, the inflammation from that infection can further lower their symptom threshold. This layered phenomenon is why patients often blame the most visible allergic trigger, like spring pollen season, when year-round allergens or residual inflammation may be contributing equally to their symptoms. Because allergy is a cumulative threshold disease, not a binary one, physicians should be mindful of potential perennial allergies contributing to patients’ symptoms during their assessment, as well as any lingering symptoms caused by viral respiratory infections.

How do year-round perennial allergies compound the onslaught of pollen allergies in the spring along with potential viral illnesses?

Because up to 80% of patients with allergies experience polysensitization, meaning they’re allergic to more than one thing, and allergens are additive, understanding what allergens the patient is sensitized to and that are contributing to their symptom threshold is critical. Sneezing, runny nose (rhinorrhea), nasal congestion, cough and postnasal drip are common to all three conditions. Itchy eyes and throat may point more strongly toward allergy, but even that isn’t exclusive.

Nonallergic rhinitis — such as vasomotor rhinitis — can also present with congestion and rhinorrhea triggered by irritants like perfumes, pollution, cigarette smoke or weather changes. Infectious rhinitis (like rhinovirus) can also produce similar symptoms, especially early in its course.

For example, a patient may already have baseline inflammation from perennial allergens like dust mites or pet dander or increased airway inflammation from a recent viral infection, but when pollen season begins, that additional trigger can push them over their symptom threshold. This layered exposure creates diagnostic ambiguity and makes it risky to rely on seasonality alone.

What symptoms are most likely to cause confusion between lingering viral illness, allergic disease or nonallergic inflammation?

The overlap between the three is significant, with symptoms like sneezing, runny nose, nasal congestion, cough and postnasal drip — all of which are common to each condition. Itchy eyes and throat may point more strongly toward a clinical allergy, but these symptoms aren’t exclusive to allergies.

Nonallergic rhinitis, such as vasomotor rhinitis, can also present with congestion and rhinorrhea triggered by irritants like perfumes, pollution, cigarette smoke or weather changes. Infectious rhinitis can produce similar symptoms, particularly early on in its course.

Because symptom patterns alone, though helpful, are insufficient to determine a diagnosis, relying solely on a patient’s symptom history could lead to misdiagnosis without diagnostic confirmation. One study found that up to 65% of patients who had received multiple prescriptions for nonsedating antihistamines had a negative IgE test result, underscoring how easily these symptom clusters can be confused.

Are there particular patient populations or risk factors that make distinguishing viral, allergic or inflammatory symptoms especially challenging?

Patients with polysensitization are particularly complex, since some may reach their symptom threshold only with layered exposures. For example, a patient may have allergies to dust mites and grass pollen, but they don’t experience symptoms until the summer, when grass pollen counts are at their highest and push them over their symptom threshold. In this instance, this can make it especially difficult to identify their other allergy to dust mites and create a truly effective symptom management plan where they reduce exposure to all their allergic triggers.

Women may present more frequently with nonallergic rhinitis, which affects an estimated 17 million to 19 million Americans and has been reported to occur about twice as often in women. Patients who frequently self-manage with over-the-counter antihistamines may also make it more difficult to reach a diagnosis, especially when combination antihistamine/decongestant products mask symptoms.

Additionally, patients with asthma may experience worsening respiratory symptoms during high pollen counts, further complicating diagnosis. One study found that outdoor pollen exposure may have an impact on asthma attacks and asthma-related hospitalizations, and that individuals with asthma may need to take preventive measures during pollen seasons.

How would a physician know when to recommend allergy testing for their patient when symptoms are unclear?

When patients present with suspected allergy symptoms, it’s a great opportunity for a comprehensive allergy assessment, starting with the most important test: an allergy-focused clinical history. Having a full picture of the patient’s symptom history is critical. If a patient has tried over-the-counter treatments like antihistamines without adequate relief and diagnosis remains uncertain after reviewing their clinical history, further clarification with diagnostic testing is important to help guide their care pathway.

If seasonal respiratory allergy symptoms are present, a comprehensive respiratory allergen sensitization profile specific to the patient’s geography will help confirm pollen and other environmental allergies and inform a personalized management plan that includes appropriate therapeutics and environmental mitigation strategies to reduce exposure to identified aeroallergens. Primary care physicians play a key role in early clarification of symptoms, especially if referral decisions are being made, to confidently manage allergic patients within their practice.

What does current research or real-world data tell us about the impact of early symptom clarification on patients’ health outcomes and health care resource utilization?

Allergy self-diagnosis or misdiagnosis can have negative or harmful impacts on patients’ allergy care, but failing to test for suspected allergens can also leave allergies undetected, leading to avoidable symptoms and a worse quality of life for patients. Underdiagnosed allergies can also put patients at risk for repeated emergency visits, heightened anxiety around uncertainty and unnecessary treatments for presumed allergies. This leaves the root cause of their symptoms unaddressed. A study from Molina Healthcare showed that identifying environmental sensitizations through specific IgE testing in patients with asthma was associated with significant reductions in asthma-related health care utilization costs.

When patients have a clear understanding of their specific triggers and take steps to avoid them, they reduce the likelihood of emergency room visits and hospitalizations, reducing overall health care resource utilization and the risk of negative health outcomes. By combining a detailed symptom history with comprehensive allergy testing, physicians can identify the true cause of a patient’s symptoms, guide more effective care, use health care resources more efficiently and improve patient safety, particularly during the late winter and early spring.

Gary Falcetano, PA, is the senior manager, Global Medical & Scientific Affairs, Allergy, at Thermo Fisher Scientific. He is a licensed physician assistant with more than 25 years of diverse experience in emergency and disaster medicine, primary care, and allergy and immunology.