Does suppression of IL-4 synthesis by aspirin explain the therapeutic benefit of aspirin desensitization treatment?

Samter's Triad: State of the Art

Samter’s triad (ST) is a well-known disease characterized by the triad of bronchial asthma, nasal polyps, and aspirin intolerance. Over the past few years, a rapid development in the knowledge of the pathogenesis and clinical characteristics of ST has happened. The aim of this paper is to review the recent investigations on the pathophysiological mechanisms and genetic background, diagnosis, and different therapeutic options of ST to advance our understanding of the mechanism and the therapeutic control of ST. As concern for ST increase, more application of aspirin desensitization will be required to manage this disease successfully. There is also a need for continued research efforts in pathophysiology, treatment, and possible prevention.

Aspirin induces IL-4 production: augmented IL-4 production in aspirin-exacerbated respiratory disease

Aspirin hypersensitivity is a hallmark of aspirin-exacerbated respiratory disease (AERD), a clinical syndrome characterized by the severe inflammation of the respiratory tract after ingestion of cyclooxygenase-1 inhibitors. We investigated the capacity of aspirin to induce interleukin-4 (IL-4) production in inflammatory cells relevant to AERD pathogenesis and examined the associated biochemical and molecular pathways. We also compared IL-4 production in peripheral blood mononuclear cells (PBMCs) from patients with AERD vs aspirin-tolerant asthma (ATA) upon exposure to aspirin. Aspirin induced IL-4 expression and activated the IL-4 promoter in a report assay. The capacity of aspirin to induce IL-4 expression correlated with its activity to activate mitogen-activated protein kinases, to form DNA-protein complexes on P elements in the IL-4 promoter and to synthesize nuclear factor of activated T cells, critical transcription factors for IL-4 transcription. Of clinical importance, aspirin upregulated IL-4 production twice as much in PBMCs from patients with AERD compared with PBMCs from patients with ATA. Our results suggest that IL-4 is an inflammatory component mediating intolerance reactions to aspirin, and thus is crucial for AERD pathogenesis.

Aspirin desensitization for patients with aspirin-exacerbated respiratory disease: A randomized double-blind placebo-controlled trial

The effect of aspirin desensitization (AD) on immunologic profile of patients with AERD has been poorly understood. This study is aimed at investigating the effect of AD on clinical and immunological markers of patients with AERD. This randomized double-blind placebo-controlled trial comprised 34 adult patients (67.6% female) with chronic rhinosinusitis, nasal polyps, and aspirin-intolerant asthma. The active group underwent AD over a 2-day period with increasing doses of aspirin (60, 125, 325, and 625 mg), followed by receiving aspirin 625 mg twice daily for 6 months. Symptom scores and medication needs of patients with AERD who have undergone AD were significantly lower compared to the placebo group after 6 months (7.5 ± 3.5 vs. 10.6 ± 3.8 and 9.3 ± 2.0 vs. 11.0 ± 3.1, respectively, all p < 0.05). However, no significant difference was observed in serum concentration of IL-10, IFN-γ, and TGF-β between two groups neither at baseline nor at the end of study.

Immunomodulatory treatments for aspirin exacerbated respiratory disease

BACKGROUND

Aspirin triad is a subclass of chronic sinusitis characterized by nasal polyposis, nonallergic induced asthma, and aspirin sensitivity. Also known as Samter's triad or aspirin-exacerbated respiratory disease, aspirin triad commonly affects the adult population and is seldom found in pediatric patients.

METHODS

This rhinosinusitis has multiple layers of pathological process, but the ultimate predicament is caused by cysteinyl leukotrienes (cysLTs).

RESULTS

Pharmacotherapies include oral steroid, lipoxygenase inhibitor, and cysLT receptor inhibitor drugs, which can provide some relief for these patients.

CONCLUSION

Immunomodulation via aspirin desensitization is considered when pharmacotherapy has failed. When aspirin triad is unmanageable with medical treatment alone, endoscopic sinus surgery with polypectomy can alleviate the patient's symptoms, allowing for a better response to postoperative medical management such as topical medication as well as delivery of topical medications.

Role of aspirin desensitization in the management of chronic rhinosinusitis

PURPOSE OF REVIEW

This review is set to revisit the pathogenesis of aspirin-exacerbated respiratory disease (AERD), the diagnostic method used, and finally the real impact of aspirin desensitization on chronic sinusitis with nasal polyposis (CRSwNP) in aspirin intolerant patients.

RECENT FINDINGS

In AERD, increased baseline production of cysteinyl-leukotriene (Cys-LT) is associated with upregulation of Cys-LT receptors on nasal inflammatory cells. This is further aggravated by inhibition of cyclooxygenase-1 by aspirin and other NSAIDs. New-found genetic markers need further study. Oral aspirin challenge is still the gold standard of diagnosis and can be safely conducted in a specialized outpatient clinic. Oral and endonasal aspirin desensitization show positive impact on CRSwNP course with decreased polyp recurrence, decreased number of hospitalizations, and decreased need for corticosteroids. Modulation of arachidonic acid metabolism and inhibition of intracellular biochemical pathways in key inflammatory cells involving anti-inflammatory cytokines interleukin (IL)-4 and IL-13 explain the clinical outcomes.

SUMMARY

Future studies should focus on establishing the lowest possible dose to maintain disease under check, allowing more widespread use of this underutilized and underrecognized treatment modality.