xRead - Nasal Obstruction (September 2024) Full Articles

20426984, 2021, 3, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/alr.22741 by Stanford University, Wiley Online Library on [01/07/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License

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International consensus statement on rhinosinusitis

state, or ciliary dyskinesia. 88 Optional allergy and immune function testing may be helpful. 88 Other conditions may produce episodic sinus symp tom mimics leading to misdiagnosis. The differential diag noses include headache (migraine, tension headache, clus ter headache), AR, non-AR, TMJ disorder, dental pain, trigeminal neuralgia, or nonspecific facial pain. Among 27 patients presenting to an otolaryngologist for “sinus” symptoms, Barham et al. showed that only 1 patient demonstrated acute CT changes consistent with RARS; the final diagnoses for the remaining patients were rhini tis (47%), headache/migraine (37%), and nonspecific facial pain (12.5%). 205 Schreiber et al. (n = 2991) showed that 88% of patients with a history of “sinus” headaches actually met International Headache Society criteria for migraine-type headache, originally misdiagnosed due to the false belief that nasal and ocular symptoms are not associated with migraine due to a tendency to asso ciate nasal and ocular symptoms as being uncharacter istic of migraine. 491 Bhattacharyya et al. discovered that the unfamiliarity with RARS as a diagnosis, particularly among non-otolaryngologists, and the underuse of nasal endoscopy and CT imaging for RARS suggested an under diagnosis of disease, resulting in significant health care costs. 232 Accurate diagnosis remains difficult but essential for optimal treatment outcome. VIII.C Pathophysiology of RARS VIII.C.1 Contributing Factors for RARS: Allergy, Immunologic Defects, and Resistant Bacteria Pathophysiologically, inflammatory edema of the sinonasal mucosa is thought to lead to obstruction of the sinus ostia, decreased MCC, and retained secretions. Several factors can predispose an individual to RARS. These include immunologic deficiencies, colonization with resistant bacteria, and allergies. Although RARS is well characterized as its own entity, few studies specif ically delineate RARS from CRS or ABRS and some of what follows is informed from conglomerated data of these various conditions. Patients with immunodeficiency are predisposed to developing RARS. The most common immunologic defi ciency in patients with RARS is humoral in nature includ ing selective IgA deficiency, IgG deficiency (both total and selective subtypes), and combined variable immunode ficiency (CVID). 492,493 Although the exact prevalence of immune deficiency in patients with RARS is unknown, a study by Chee et al. found that 40% of patients with RARS had some form of anergy. 493 Many patients with

mild immunodeficiencies, especially selective IgA defi ciency can be otherwise asymptomatic, increasing the dif ficulty in diagnosis. Patients with RARS have been found to have abnormalities in the antimicrobial factors of their nasal glandular secretion; specifically decrease in levels of IgA, lactoferrin, and lysozyme proteins. 494 In patients with CVID, approximately 66% will develop RARS. 495 Other causes of immune deficits can also predispose patients to RARS such as human immunodeficiency virus-acquired immunodeficiency syndrome (HIV-AIDS) or patients with hematopoietic stem cell transplantation. 496,497 In patients with HIV-AIDS, there appears to be a correla tion between decreasing CD4 count and increasing rates of ABRS. 496 The microbiology of ABRS is well established with the most common pathogens being Streptococcus pneumoniae , Haemophilus influenzae , and Moraxella catarrhalis . 498 Studies have shown similar bacterial pathogens implicated inRARS. 10 However, in patients with RARS, about 62.5% of bacterial isolates develop antimicrobial resistance. 499 In addition, the bacterial isolate during repeat culture changes in 59% of patients. 499 These changes can prove challenging in treatment of patients with RARS encourag ing the use of culture driven antibiotic therapy and avoid ance of incorrect antibiotic overuse. The relationship between allergies and RARS is contro versial. The inflammation associated with allergic disor ders can lead to increased susceptibility to recurrent sinus infections. Some reports demonstrated an increase in posi tive allergy testing in patients with RARS while others sug gested lower rates of allergies in patients with RARS com pared to CRS. 500,501 This difference may be explained by difficulty in differentiating RARS from an acute on chronic rhinosinusitis exacerbation. In an attempt to differentiate AR from RARS, 1 study found an increase in the expres sion of toll-like receptor 9 in the sinonasal epithelium in patients with AR and RARS compared with patients with ARalone. 502 This finding may be the result of the upregu lation of innate markers after repeated microbial insults. In conclusion, there is a paucity of information on the pathophysiology of RARS in the literature and what is available is controversial. The available data suggests that patients with immunologic deficits, allergies, and colo nization with resistant bacteria are predisposed to RARS (Table VIII-3).

Allergy, Immunologic Defects, and Resistant Bacteria as a Contributing Factor for RARS Aggregate Grade of Evidence: C (Level 3: 4 studies, Level 4: 6 studies; Table VIII-3).