Aspirin-Exacerbated Respiratory Disease (AERD), often referred to as Samter’s Triad, is a chronic medical condition characterized by a combination of asthma, sinus disease with recurring nasal polyps, and a distinctive sensitivity to aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs). This sensitivity stems from NSAIDs inhibiting cyclooxygenase-1, an enzyme in the body. Reactions to these drugs typically manifest as respiratory issues when ingested or inhaled, although the precise mechanism behind these reactions remains unclear. AERD affects approximately 9% of adults with asthma and a significant 30% of individuals who have both asthma and nasal polyps. The onset of AERD is usually abrupt and occurs in adulthood, most commonly between the ages of 20 and 50, often without a discernible initial trigger.
Symptoms of AERD: Recognizing the Triad
Patients with AERD commonly experience a cluster of symptoms including asthma, persistent nasal congestion, and the recurrence of nasal polyps. These symptoms are often resistant to standard treatments. Chronic sinus infections are frequently reported, and a diminished sense of smell is a common complaint among individuals with AERD.
A hallmark of AERD is the adverse reaction to aspirin and other NSAIDs. These reactions typically involve both upper and lower respiratory tract symptoms. Upper respiratory symptoms may include increased nasal congestion, frontal headaches or sinus pressure, and episodes of sneezing. Lower respiratory symptoms can manifest as coughing, wheezing, and chest tightness. In addition to respiratory symptoms, some individuals may experience skin flushing, rashes, abdominal pain, and, in some cases, vomiting following NSAID exposure.
Interestingly, alcohol consumption can also trigger reactions in about 75% of AERD patients. These reactions are usually mild to moderate respiratory symptoms and can occur with various types of alcohol, even after consuming a small amount, such as less than one glass.
Diagnosing AERD: Clinical Evaluation and Aspirin Challenge
The diagnosis of AERD is primarily clinical, relying on the patient’s medical history and symptom presentation rather than a single definitive test. The presence of the classic triad – asthma, nasal polyps, and respiratory reactions to NSAIDs – is crucial for AERD diagnosis. However, when there is uncertainty about a patient’s history of NSAID reactions, an aspirin challenge is often conducted to confirm the diagnosis of aspirin sensitivity and AERD.
An aspirin challenge is a medical procedure performed under close supervision in a hospital or clinic setting by experienced medical professionals. This challenge can be administered orally, or through a combination of intranasal and oral methods. It involves gradually increasing doses of aspirin to observe if a reaction occurs, thereby confirming aspirin sensitivity and supporting the AERD diagnosis.
Furthermore, individuals with AERD often exhibit elevated levels of eosinophils, a type of white blood cell involved in inflammation, in their nasal polyps and sometimes in their blood. While not a mandatory criterion for AERD diagnosis, the presence of increased eosinophils can provide additional supportive evidence for clinicians. Therefore, eosinophil levels can be a helpful insight during the diagnostic process, complementing the clinical picture and aspirin challenge results.
Treatment and Management Strategies for AERD
For individuals diagnosed with AERD who have not undergone aspirin desensitization, strict avoidance of all NSAIDs is essential to prevent adverse reactions. However, even with NSAID avoidance, the underlying symptoms of asthma, nasal congestion, and polyp recurrence persist and require ongoing management. Acetaminophen (paracetamol) is generally considered safe at lower doses (up to 500mg per dose) for pain relief in AERD patients.
The cornerstone of AERD management involves daily medications to control symptoms. Inhaled corticosteroids are frequently prescribed for asthma management. Intranasal steroid sprays or sinus rinses can help alleviate nasal symptoms, and oral steroids may be used periodically to manage nasal polyps. Additionally, non-steroidal medications like leukotriene modifiers (zileuton, montelukast, and zafirlukast) are available to target specific inflammatory pathways and reduce symptom burden. Despite comprehensive medical management, surgical removal of nasal polyps is often necessary in AERD patients, although polyp recurrence rates post-surgery remain high.
Aspirin desensitization followed by daily high-dose aspirin therapy represents a significant treatment strategy for some AERD patients, potentially reducing reliance on steroids. Aspirin desensitization is a carefully controlled procedure performed in specialized medical facilities. The goal is to enable patients to tolerate daily aspirin, which, in some cases, can slow down nasal polyp regrowth and decrease the need for corticosteroid medications.
The advent of newer biologic medications has further expanded treatment options for AERD, particularly for those with severe asthma and nasal polyps. Biologics such as mepolizumab, benralizumab, reslizumab, and dupilumab are indicated for severe eosinophilic asthma. Omalizumab is used for severe allergic asthma and chronic rhinosinusitis with nasal polyps, while mepolizumab and dupilumab also have indications for chronic rhinosinusitis with nasal polyps. These specialized medications offer targeted approaches to managing inflammation and improving outcomes for many individuals living with Aspirin-exacerbated respiratory disease (AERD).
