Factors confusing the diagnosis of laryngopharyngeal reflux: the role of allergic rhinitis and inter-rater variability of laryngeal findings

Abstract

The objective of the study was to determine the inter-rater variability in assessment of laryngeal findings and whether diagnosing laryngopharyngeal reflux based on the laryngeal findings and history alone without considering allergic rhinitis leads to the overdiagnosis and overtreatment of laryngopharyngeal reflux. Patients with positive and negative skin prick tests were recruited from an allergy clinic in a tertiary teaching university hospital. All subjects completed the Reflux Symptom Index (RSI) and underwent laryngeal examinations by three physicians blinded to the skin prick test results and the Reflux Finding Score (RFS) was determined. RFS >7 or RSI >13 was considered reflux positive. Fleiss' kappa (κ) was used to measure inter-rater agreement. The inter-rater agreement was low for pseudosulcus vocalis (κ = 0.078), ventricular obliteration (κ = 0.206), diffuse laryngeal edema (κ = 0.204), and posterior laryngeal hypertrophy (κ = 0.27), intermediate for laryngeal erythema/hyperemia (κ = 0.42) and vocal fold edema (κ = 0.42), and high for thick endolaryngeal mucus (κ = 0.61). Although the frequency of allergy was high, there was no significant difference between allergy-positive and laryngopharyngeal reflux-positive patients. On logistic regression analysis, thick endolaryngeal mucus was a significant predictor of allergy (p = 0.012, odds ratio 0.264, 95 % confidence interval 0.093-0.74). The laryngeal examination for reflux is subject to marked inter-rater variability and allergic laryngitis was not misdiagnosed as laryngopharyngeal reflux. The presence of thick endolaryngeal mucus should alert physicians to the possibility of allergic rhinitis/laryngitis.

The factors associated with allergic rhinitis in the dysphonic professional voice users

“…Some authors think that the studies made until now did not confirm that LPR is so much present among dysphonic patients (26)(27)(28), and there is a significant overlap in the symptomatic presentation of patients with LPR and allergic laryngitis (15,28). The LPR and AR are difficult to be differentiated because they have similar signs and symptoms as reported.…”

Reflux and Voice Disorders: Have We Established Causality?

“…Specificity and reliability of the RFS and laryngeal LPR findings in general, have been scrutinized and challenged by several studies. 33–39 In its initial validation, the RFS was found to have an inter-rater correlation coefficient (ICC) of 0.90; indicating near perfect agreement among laryngologist-raters. 32 Since, documented inter-rater agreement has been less impressive, ranging from poor to fair.…”

“…32 Since, documented inter-rater agreement has been less impressive, ranging from poor to fair. 33, 35, 37, 39, 40 In one study, for example, only 35% of those with abnormal RFS had pathological reflux on pH studies, suggesting that true identification of LPR is occurring about 1/3 of time in clinical settings that primarily rely on physical findings to diagnose LPR in symptomatic patients. 38 Other authors reported discordance between RFS and pH results in 53% of participants referred for LPR evaluation.…”

“…44 It has therefore been posited that these signs represent a tissue continuum rather than distinct pathology. These ratings can also be confounded by a number of conditions and diagnostic variables including presence of allergic rhinitis, 39 type of scope used to evaluate the larynx, 43 and the endoscopist a priori knowledge of patient symptoms. 35 After reviewing the evidence, the American College of Gastroenterology rejected the notion that reflux can be diagnosed by laryngoscopy alone.…”

Factors associated with lingual tonsil hypertrophy in Canadian adults

“…There is also an emerging body of evidence that suggests environmental allergies may cause laryngeal symptoms, however, the symptom overlap and comorbidity between allergy and LTH has yet to be fully elucidated [4, 5]. The purpose of this study was to determine what factors are associated with LTH in a population of Canadian adults.…”