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Wise et al.

Page 158

Inner ear disease— Meniere’s disease is characterized by recurring episodes of tinnitus, hearing loss, aural fullness, and vertigo. The basic pathophysiologic defect in Meniere’s disease appears to be a dysregulation of endolymph in the inner ear (endolymphatic hydrops). 1975 An immunologically-mediated disturbance in fluid handling by the endolymphatic sac has been postulated as 1 cause for the disease. 1976 The notion that “allergy” of the inner ear is a cause of Meniere’s disease predates our modern understanding of type 1 IgE-mediated hypersensitivity, and is still evoked as a possible causative or contributing factor for the disease in some individuals. Indeed, AR has been postulated as a cause of inner ear dysfunction, 1977 and a connection between allergy and inner ear disorders such as Meniere’s disease is plausible based on compiled circumstantial evidence. Derebery and colleagues have published studies suggesting that inhalant and food allergies are more common in Meniere’s patients, 1978 and that allergy treatment including AIT results in improved Meniere’s disease symptoms. 1979,1980 However, these studies generally provide low grade evidence, and aside from 1 small study that also found a higher prevalence of IgE mediated hypersensitivity in Meniere’s patients, 1981 these findings have not been duplicated by others. Case-control studies examining total serum IgE levels have provided conflicting results. 1981,1982 A few small studies have shown changes in objective parameters such as the electrocochleographic summating potential/action potential (SP/AP) ratio in response to aeroallergen or food challenge in Meniere’s patients. 1983,1984 Overall, the evidence supporting a connection between type 1 IgE-mediated hypersensitivity and Meniere’s disease is of low grade, with substantial defects in study design (Table X.G-3). • Aggregate Grade of Evidence: C (Level 3b: 4 studies; Level 4: 4 studies; Table X.G-3). X.H. Cough— Cough is a sudden reflex used to clear the breathing passage of any foreign particles or irritants. There is evidence that vagal afferent nerves regulate an involuntary cough; yet, there is also cortical control of this overall visceral reflex. 1985 Cough is often considered a comorbidity of AR. The rhinobronchial reflex is 1 of the mechanisms that may explain the ability of stimuli on the nasal mucosa, such as an allergen, to result in direct bronchospasm. 1986 The role of descending secretions (postnasal drip) from the upper to lower airways is a second theory. While many practitioners link postnasal drainage to cough, there is very little evidence to support this. When functioning normally, the vocal folds protect the lower airways from upper airway secretions and foreign bodies. Third, a direct mechanism due to diffuse inflammation and activation of eosinophils may be responsible for the common upper and lower airway manifestations. The American College of Chest Physicians evidence-based clinical practice guidelines on cough suggest the term upper airway cough syndrome, rather than postnasal drip syndrome, when discussing a cough originating from the upper airway due to the varying possible causes. 1985 AR and asthma may coexist and may indeed produce a continuum of the same airway disease. 1167 Associations with cough in AR patients can relate to their underlying asthma or a seasonal asthma during peak pollen season. The Asia Pacific Burden of Respiratory Diseases study, a 1000-person cross-sectional observational study, revealed that cough was the primary reason for a visit to the physician for patients with asthma and or COPD. However, AR patients were more likely to present with classic watery, sneezing, runny nose.

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Int Forum Allergy Rhinol . Author manuscript; available in PMC 2020 June 10.