Autologous serum skin test reactivity and basophil histamine release test in patients with nasal polyposis: preliminary results

The causal relationship between multiple autoimmune diseases and nasal polyps

Background

Although previous sporadic studies have reported the associations between a few autoimmune diseases and nasal polyps, these studies have limitations such as conflicting results, small sample sizes, and low levels of evidence.

Methods

Several autoimmune diseases were selected as exposures while the nasal polyps were selected as outcomes. Bidirectional univariable Mendelian randomization and multivariable Mendelian randomization analyses were performed after rigorous screening of instrumental variables. Then mediation analyses were conducted to further investigate the underlying mechanisms.

Results

For the first time, we investigated the causal relationships between nine autoimmune diseases and nasal polyps in different genders and found: (1) there was a causal association between adult-onset Still's disease and nasal polyps; (2) sarcoidosis, ulcerative colitis, type 1 diabetes, and Crohn's disease had no significant associations with nasal polyps; (3) celiac disease showed a suggestive positive association with female nasal polyps, whereas juvenile arthritis and multiple sclerosis showed suggestive positive associations with male nasal polyps. By contrast, arthropathic psoriasis showed a suggestive negative association with nasal polyps. In addition to these nine diseases, previous controversial issues were further investigated: (1) there was a causal relationship between rheumatoid arthritis and nasal polyps, which was partially mediated by "BAFF-R for IgD+ B cells"; (2) ankylosing spondylitis showed suggestive positive associations with the female but not the male nasal polyps. Besides, we validated that there was no causal effect of autoimmune hyperthyroidism on nasal polyps.

Conclusion

Specific conclusions regarding the causal effects of multiple autoimmune diseases on nasal polyps are the same as above. By comparing results between different genders, we have initially observed the sex bimodality in the causal effects between autoimmune diseases and nasal polyps, with those on male nasal polyps being stronger than those on female nasal polyps. Our study lays a solid foundation for further research in the future, not only helping identify individuals susceptible to nasal polyps early but also improving our understanding of the immunopathogenesis of these heterogeneous diseases.

Evidence and role of autoantibodies in chronic rhinosinusitis with nasal polyps

In this study, we review our current knowledge of the autoimmune etiopathogenesis of chronic rhinosinusitis with nasal polyps including bacterial infections, viral infections and immunomediated mechanisms and to discuss pathogenesis with relevance for pharmacotherapy. Relevant publications on the etiopathogenesis and treatment of chronic rhinosinusitis with nasal polyps (CRSwNP) from 1977 to 2013 were analyzed. The characteristic signs and symptoms include appearance of relapsing nasal polyps, with typical symptoms such as nasal obstruction, nasal discharge and, usually, loss of the sense of smell. The etiology and pathogenesis remain unknown. Proposed theories of causation include bacterial or viral infections and immunomediated mechanisms. The autoimmune aetiology of unknown origin or failure to respond to classic pharmacological treatments with nasal and oral steroids is now suspected. At present, the nature of the antigen trigger, the exact role played by B/T cells and anti-dsDNA autoantibodies in the pathogenesis of nasal polyposis remains unclear. Corticosteroids and surgery are the first line of treatment in CRSwNP. In the case of corticosteroid treatment failure, other drugs can be used such as rituximab, belimumab or omalizumab which have demonstrated clinical efficacy in the treatment of nasal polyposis with comorbid asthma. Immunosuppressive drugs such as methotrexate, and cyclophosphamide have also been used with varying degrees of success.

Inflammatory Markers: Serum Amyloid A, Fibrinogen and C-Reactive Protein — A Revisited Study

The acute phase response is the part of the innate defence system of an animal against trauma, inflammation or infection. During this response, there is increased production and release of certain plasma proteins known as acute phase proteins, which include C-reactive protein (CRP), serum amyloid A (SAA) and fibrinogen (Fg). CRP consists of five identical subunits of 206 amino acids with a molecular weight of approximately 23 kDa. There is strong evidence from numerous studies that CRP is a predictor of inflammation. The acute-phase protein serum amyloid A (SAA) is a clinically useful marker of inflammation. SAA plays not only an important role in the development of AA amyloidosis (an important complication of rheumatoid arthritis) but also interacts with events closely involved in the metabolic syndrome as a high- and low-grade inflammatory modulator. Fibrinogen (Fg) is a high molecular weight plasma adhesion protein and is a biomarker of inflammation. It is synthesized and assembled in hepatocytes and fibroblasts and when secreted into the circulation, its plasma half-life ranges from 3 to 4 days. Several cytokines, are involved in the induction of acute phase protein synthesis, but the mutual importance of these cytokines seems to be cell-type specific and to vary in various experimental settings. Here we revisited the classic acute phase proteins SAA, C-Reactive protein and fibrinogen in their role in inflammation and their interrelationship with some cytokines.