Post-tonsillectomy taste dysfunction: Myth or reality?

Lingual branches of the glossopharyngeal nerve (CN Ⅸ) are at risk of injury during ton-sillectomy due to their proximity to the muscle layer of the palatine tonsillar bed. However, it is unclear how often this common surgery leads to taste disturbances. We conducted a literature search using PubMed, Embase, Cochrane Library, Google Scholar, PsychInfo, and Ovid Medline to evaluate the available literature on post-tonsillectomy taste disorders. Studies denoting self-reported dysfunction, as well as those employing quantitative testing, i.e., chemogustometry and electrogustometry, were identified. Case reports were excluded. Of the 8 original articles that met our inclusion criteria, only 5 employed quantitative taste tests. The highest prevalence of self-reported taste disturbances occurred two weeks after surgery (32%). Two studies reported post-operative chemical gustometry scores consistent with hypogeusia. However, in the two studies that compared pre- and post-tonsillectomy test scores, one found no difference and the other found a significant difference only for the left rear of the tongue 14 days post-op. In the two studies that employed electrogustometry, elevated post-operative thresholds were noted, although only one compared pre- and post-operative thresholds. This study found no significant differences. No study employed a normal control group to assess the influences of repeated testing on the sensory mea-sures. Overall, this review indicates that studies on post-tonsillectomy taste disorders are limited andambiguous.Future researchemploying appropriate control groups andtaste testingprocedures are needed to define the prevalence, duration, and nature of post-tonsillectomy taste disorders.

Impact of antibiotics on smell dysfunction

Objective: Viral or bacterial respiratory infections can cause long-lasting olfactory dysfunction. Antibiotic therapy is indicated in severe cases; however, it is unclear whether antibiotic use produces a positive, negative, or null effect on olfactory function. This retro-spective study sought to determine whether antibiotic use has an influence on odor identifica-tion and detection threshold test scores of patients with smell dysfunction secondary to upper respiratory infections (URIs), lower respiratory infections (LRIs), or rhinosinusitis. Methods: Data from a total of 288 patients presenting to the University of Pennsylvania Smell and Taste Center were evaluated. Results: Patients with a URI etiology who had taken bactericidal antibiotics had lower detec-tion thresholds than did patients who had not taken antibiotics (P < 0.023; analysis of covari-ance with age and time since infection onset as covariates). Moreover, thresholds were lower for bactericidal antibiotic users than for bacteriostatic antibiotic users with either URI (P = 0.023) or rhinosinusitis (P = 0.028) etiologies. No meaningful influences of antibiotics on the odor identification test scores were evident. Conclusions: These findings, which need to be confirmed in prospective double-blind studies, suggest that bactericidal antibiotic therapy may be beneficial in mitigating, at least to some degree, chronic decrements in smell sensitivity due to URIs and rhinosinusitis.

Measurement of chemosensory function

Although hundreds of thousands of patients seek medical help annually for disor-ders of taste and smell, relatively few medical practitioners quantitatively test their patients' chemosensory function, taking their complaints at face value. This is clearly not the approach paid to patients complaining of visual, hearing, or balance problems. Accurate chemosensory testing is essential to establish the nature, degree, and veracity of a patient's complaint, as well as to aid in counseling and in monitoring the effectiveness of treatment strategies and de-cisions. In many cases, patients perseverate on chemosensory loss that objective assessment demonstrates has resolved. In other cases, patients are malingering. Olfactory testing is crit-ical for not only establishing the validity and degree of the chemosensory dysfunction, but for helping patients place their dysfunction into perspective relative to the function of their peer group. It is well established, for example, that olfactory dysfunction is the rule, rather than the exception, in members of the older population. Moreover, it is now apparent that such dysfunction can be an early sign of neurodegenerative diseases such as Alzheimer's and Parkin-son's. Importantly, older anosmics are three times more likely to die over the course of an ensuring five-year period than their normosmic peers, a situation that may be averted in some cases by appropriate nutritional and safety counseling. This review provides the clinician, as well as the academic and industrial researcher, with an overview of the available means for accurately assessing smell and taste function, including up-to-date information and normative data for advances in this field.

Preface

Although often taken for granted, odors and tastes signifi-cantly impact our everyday lives, influencing our eating habits, nutrition, and safety. How many of us look forward to the aroma of brewing coffee and sizzling bacon in the morning and a delicious dinner accompanied by a fine wine in the evening?