Risk Factors for Olfactory and Gustatory Dysfunctions in Patients with SARS-CoV-2 Infection.

INTRODUCTION: Smell and taste loss are characteristic symptoms of SARS-CoV-2 infection. The aim of this study is to investigate the prevalence and risk factors associated with olfactory and gustatory dysfunctions in coronavirus disease (COVID-19) patients. METHODS: We conducted an observational, retrospective study on 376 patients with documented SARS-CoV-2 infection admitted to the San Gerardo Hospital in Monza, Italy, from March to July 2020. All patients answered a phone questionnaire providing information on age, sex, smoking status, and clinical characteristics. Adjusted odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated through logistic regression models including relevant covariates. RESULTS: The prevalence of olfactory and gustatory dysfunctions in COVID-19 patients was 33.5 and 35.6%, respectively. Olfactory dysfunctions were significantly directly associated with current smoking and history of allergy, the multivariable ORs being 6.53 (95% CI 1.16-36.86) for current smokers versus never smokers, and 1.89 (95% CI 1.05-3.39) for those with an allergy compared to those without any allergy. Respiratory allergy in particular was significantly associated with olfactory dysfunctions (multivariable OR 2.30, 95% CI 1.02-5.17). Significant inverse associations were observed for patients aged 60 years or more (multivariable OR 0.33, 95% CI 0.19-0.57) and hospitalization (multivariable OR 0.22, 95% CI 0.06-0.89). Considering gustatory dysfunctions, after allowance of other variables a significant direct association was found for respiratory allergies (OR 2.24, 95% CI 1.03-4.86), and an inverse association was found only for hospitalization (OR 0.21, 95% CI 0.06-0.76). CONCLUSION: Our study indicates that current smoking and history of allergy (particularly respiratory) significantly increase the risk for smell loss in COVID-19 patients; the latter is also significantly associated to taste loss. Hospitalization has an inverse association with the risk of olfactory and gustatory dysfunctions, suggesting that these may be symptoms characteristics of less severe SARS-CoV-2 infection.

Recognition of taste in patients during antineoplastic therapy with platinum drugs.

Taste changes caused by the use of platinum drugs have been described. However, few studies qualify the impaired tastes and whether these changes are derived exclusively from chemotherapy (QTx). AIMS: Evaluation of changes in sweet, sour, salty, bitter, and umami tastes in patients receiving QTx with platinum drugs was the aim of this study. METHODS: A total of 43 subjects, 21 from the study group and 22 from the control, were studied in two time periods, one before the start of QTx (T0) and another after two cycles of QTx (T1). The usual dietary intake, body mass index (BMI), handgrip strength and fatigue (through the fatigue pictogram) were evaluated to characterize the group studied. Taste Strips tests were performed for all 4 tastes and umami was studied by comparing Likert's scale using monosodium glutamate (GMS) food. Statistical analysis was performed using repeated measures (ANOVA), mixed model, with significance level p≤0.05. RESULTS: Salty and sour were the most affected tastes in the study group (p = 0.001 and 0.05); as well as the ionotropic receptors (p = 0.02) responsible for identifying these tastes. There was a difference between the times for BMI, dynamometry and impact in daily activities, by the fatigue pictogram (p = 0.008, 0.009 and 0.006 respectively). CONCLUSION: These findings suggest an important role in altering taste recognition, mainly in salty and sour tastes, identified by ionotropic receptors, which seems to be related to dietary changes. QTx has demonstrated a contribution to impairment of functionality and fatigue.

Hypoglossal acupuncture for acute chemotherapy-induced dysgeusia in patients with breast cancer: study protocol of a randomized, sham-controlled trial.

BACKGROUND: Distortion of taste sensations is a common chemotherapy-induced side effect; however, treatment evidence is limited. Pilot data indicated that acupuncture might be able to improve symptoms of dysgeusia. Thus, the aim of this study is to investigate the effects and side effects of hypoglossal acupuncture in the treatment of dysgeusia in patients with breast cancer undergoing chemotherapy. METHODS/DESIGN: The study is a randomized controlled trial comparing a single verum acupuncture treatment with two active comparators: sham acupuncture and dietary recommendations. Sample size calculation revealed a total of 75 patients pending an alpha of 0.05, a power of 0.8, and an estimated effect size of 0.80. Patients with breast cancer undergoing platinum- or taxane-based chemotherapy will be included if they present with phantogeusia (abnormal taste sensations without an external oral stimulus) with an intensity of 4 points or above on an 11-point numeric rating scale (NRS). The primary outcome is phantogeusia; secondary outcomes include parageusia (abnormal taste of food), hypogeusia (reduced taste sensations), hypergeusia (increased taste sensations), xerostomia (dry mouth), stomatitis, appetite, and functional impairment. All outcomes will be assessed at baseline and prior to the next chemotherapy administration using an 11-point NRS for each. All adverse events will be recorded. DISCUSSION: The results of this study will demonstrate the extent to which hypoglossal acupuncture may influence the intensity of and functional impairment due to chemotherapy-induced dysgeusia. TRIAL REGISTRATION: Clinical Trials.gov, NCT02304913 . Registered on 19 November 2014.

The experience of dysgeusia in allogeneic haematopoietic cell transplantation survivors: a qualitative study.

BACKGROUND: Taste disorders are one of the most common side effects of treatment in oncology patients and often occur after allogeneic haematopoietic cell transplantation (allo-HCT). Dysgeusia does not receive close medical attention, and information about this disorder is largely based on the clinician's own experience. However, taste disorders can have an impact on the quality of life and nutritional status of survivors of allo-HCT. The number of performed annual transplantations is growing, as the number of older long-term survivors increases, but only few research studies examine survivors of allo-HCT with taste disorders. We conducted a qualitative descriptive study to explore experiences of dysgeusia in patients undergoing allo-HCT and to examine what strategies they used to mitigate it. METHODS: Using purposeful sampling, survivors of allo-HCT were recruited. Audiotape interviews were conducted until data saturation was achieved. Each interview was transcribed verbatim, and content analyses were performed to extract significant themes and subthemes. RESULTS: Three major themes embracing various aspects of allo-HCT survivors' experiences were identified: (1) the shape of taste; (2) everything is irritating and it is arduous to eat; (3) finding new strategies to overcome the problems. Together, they highlight the experiences of survivors showing how the taste disorders can affect the physical, psychological and social dimensions of a person. CONCLUSION: A cumulative burden is the result of dysgeusia and its clinical course reinforced also by related symptoms. Healthcare professionals must focus their attention on the management of these symptoms and offer interventions to safeguard the patient's social, physical and psychological well-being.

Salty taste thresholds and preference in patients with chronic kidney disease according to disease stage: A cross-sectional study.

AIM: The present study was performed to evaluate the differences in salty taste thresholds among normal controls and non-dialysis chronic kidney disease (CKD) patients according to disease stage and to evaluate the relationship between salty taste thresholds or preferences and mean spot urine sodium concentrations. METHODS: This cross-sectional study enrolled 436 patients with non-dialysis CKD and 74 normal controls. We evaluated detection and recognition thresholds, salty taste preferences and salt usage behaviours (through a questionnaire) in CKD patients and normal controls. We averaged the three most recent spot urine sodium concentrations and used this 'mean spot urine sodium' value to estimate sodium intake in CKD patients. RESULTS: Detection thresholds of stages 3 and 5 and recognition thresholds of stage 3 CKD patients were higher than those of normal controls. Salty taste preferences of stage 5 and salt usage behaviour scores of stages 4 and 5 CKD patients were lower than those of normal controls. Univariate analysis showed that estimated glomerular filtration rate (eGFR), salt usage behaviour score, salty taste preference, smoking, gender and zinc level were significantly associated with mean spot urine sodium in CKD patients. Multiple regression analysis showed that the eGFR and salty taste preference were independently correlated with mean spot urine sodium. CONCLUSIONS: Education to change salty taste preferences and regular follow up are necessary to decrease salt intake in CKD patients.

Unlocking the Complex Flavors of Dysgeusia after Hematopoietic Cell Transplantation.

Dysgeusia is a frequently occurring symptom after hematopoietic cell transplantation (HCT) that has important long-term effects on physical, nutritional, and immunologic recovery, as well as on quality of life. Despite the relevance of this symptom, the study of dysgeusia in patients undergoing HCT has been limited, owing in part to its complexity. In this article, we review normal taste function and its clinical evaluation, discuss how dysgeusia uniquely affects patients undergoing HCT, and examine distinct, transplantation-related contributors to dysgeusia that may help elucidate strategies to ultimately reduce this symptom burden after transplantation.

Change of somatosensory function of the tongue caused by chorda tympani nerve disorder after stapes surgery.

OBJECTIVES: Patients after middle ear surgery often complain of taste disturbance and a lingual numbness. The purpose of this study was to objectively assess changes in the somatosensation of the tongue and taste function in patients undergoing stapes surgery. STUDY DESIGN: Prospective study. METHODS: Symptoms of taste disturbance and tongue numbness after surgery were investigated before and after surgery in 41 patients (13 males, 28 females; mean age 41.8 years) who underwent stapes surgery. Twenty-eight patients (9 males, 19 females; mean age 43.1 years) underwent sensory and taste function tests before and after surgery. Sensory function of the tongue was measured at the operated side and the nonoperated side using the 2-point discrimination test and an electrostimulator test. Taste function was assessed with electrogustometry (EGM). RESULTS: The chorda tympani nerve (CTN) was gently touched or stretched in all patients. Postoperative thresholds on the operated side were significantly higher than preoperative thresholds in all tests in the patients who underwent all three kinds of tests. Tongue somatosensory symptoms improved significantly earlier than the taste disturbance postoperatively, and the sensory thresholds returned to the baseline along with recovery of symptoms. CONCLUSION: These findings suggest that dysfunction of the CTN occurred following surgery even when the CTN was preserved, and that the sensory nerve threshold of the tongue correlated with the symptom of lingual numbness. The CTN may play a role not only in taste function but also in the somatosensory function of the tongue. LEVEL OF EVIDENCE: 4. Laryngoscope, 128:701-706, 2018.

Recovery of taste organs and sensory function after severe loss from Hedgehog/Smoothened inhibition with cancer drug sonidegib.

Striking taste disturbances are reported in cancer patients treated with Hedgehog (HH)-pathway inhibitor drugs, including sonidegib (LDE225), which block the HH pathway effector Smoothened (SMO). We tested the potential for molecular, cellular, and functional recovery in mice from the severe disruption of taste-organ biology and taste sensation that follows HH/SMO signaling inhibition. Sonidegib treatment led to rapid loss of taste buds (TB) in both fungiform and circumvallate papillae, including disruption of TB progenitor-cell proliferation and differentiation. Effects were selective, sparing nontaste papillae. To confirm that taste-organ effects of sonidegib treatment result from HH/SMO signaling inhibition, we studied mice with conditional global or epithelium-specific Smo deletions and observed similar effects. During sonidegib treatment, chorda tympani nerve responses to lingual chemical stimulation were maintained at 10 d but were eliminated after 16 d, associated with nearly complete TB loss. Notably, responses to tactile or cold stimulus modalities were retained. Further, innervation, which was maintained in the papilla core throughout treatment, was not sufficient to sustain TB during HH/SMO inhibition. Importantly, treatment cessation led to rapid and complete restoration of taste responses within 14 d associated with morphologic recovery in about 55% of TB. However, although taste nerve responses were sustained, TB were not restored in all fungiform papillae even with prolonged recovery for several months. This study establishes a physiologic, selective requirement for HH/SMO signaling in taste homeostasis that includes potential for sensory restoration and can explain the temporal recovery after taste dysgeusia in patients treated with HH/SMO inhibitors.

[Taste dysfunction (dysgeusia) and radioiodine therapy of thyroid cancer - be aware of side effects by antidepressants and sedatives. Vorschädigung durch Antidepressiva und Sedativa beachten]. / Geschmacksstörung (Dysgeusie) und Radioiodtherapie des Schilddrüsenkarzinoms. Vorschädigung durch Antidepressiva und Sedativa beachten.

In addition to xerostomia, taste dysfunction (hypo-, dysgeusia) is an independent side effect of radioiodine therapy of thyroid cancer. Hypogeusia results from damage of the small mucous salivary glands in the vicinity of the taste buds. Particularly in those patients, who are treated with drugs such as antidepressants or sedatives, taste dysfunction becomes frequently clinically symptomatic. If feasible, therapy regimens bearing a potential risk for taste dysfunction should be switched. Additional damage to taste function should be minimalized, including cessation of smoking, change of agents for dental hygiene, and change of toothpaste. If the medical indication for ablative radioiodine therapy is based on the patient's decision, the patient should be informed about alternative strategies. Potential clinical consequences of the sialadenitis (xerostomia, alteration in taste, risk of caries and tooth extraction, lacrimal gland dysfunction, tearing and need of dacryocystorhinostomy) should be revealed completely. Adapted to the initial risk of relapse, the 131I-activity for ablation should be reduced to the latest standard of care. Clinical data are currently too heterogeneous to decide whether rhTSH might reduce the rate of dysgeusia. The specialist in nuclear medicine should be aware of the multifactorial causes of taste dysfunction, in particular if the patient seeks medical advice after radioiodine therapy.

The Impact of Aging and Medical Status on Dysgeusia.

Disorders of taste and smell can cause an aversion to food in a sick patient and therefore affect his/her ability to maintain optimal nutrition. This can lead to a reduced level of strength, muscle mass, function, and quality of life. Additionally, reduced ability to differentiate between various intensities or concentrations of a tastant can result in increased intake of salt and sugar and exacerbation of chronic diseases such as heart failure and diabetes. These implications can be heightened in the elderly, who are particularly frail and are challenged by polypharmacy and multiple comorbid conditions. In this article, we will review the prevalence, etiology, and management of taste disorders. Additionally, we will review the association between taste and smell disorders and how disorders of smell can affect perception of taste.

Taste sensation following cochlear implantation surgery.

OBJECTIVES: The chorda tympani nerve (CTN) is at risk of damage during cochlear implantation, especially during posterior tympanotomy. The aim of this study was, therefore, to elicit the risk of taste disorders following cochlear implantation surgery involving a mastoidectomy and a posterior tympanotomy approach. METHOD: Twenty-six patients underwent a taste test before, 3 days after, and 6 weeks after cochlear implantation surgery. The taste sensations - sweet, sour, salt and bitter - were determined. Patients' self-ratings of taste function were also obtained. In addition, the surgeons provided information concerning the intraoperative status of the CTN. RESULTS: In total, 19.2% (5 of 26) of the patients had postoperative taste dysfunction, as measured either subjectively or objectively or both. One of these five individuals had taste disturbance as assessed by both subjective and objective measures; in another, it was merely reported subjectively. Three patients were subjectively asymptomatic but the postoperative taste test revealed a dysfunction. Sixteen percent of the patients in whom the CTN was reported to be preserved intraoperatively had a postoperative taste dysfunction. Although the CTN was rerouted in five patients, only two of them (40%) had transient gustatory dysfunction. In two of those patients with postoperative taste dysfunction, the CTN was not intraoperatively exposed (being protected by bone) despite these individuals' experiencing postoperative taste problems. The recovery rate was 100% at 6 weeks after surgery. CONCLUSION: Our study indicates that cochlear implantation entails only a minimal risk of taste dysfunction and that this is chiefly a transient problem.

Taste disorders after tonsillectomy: a long-term follow-up.

In a former study, taste disturbances after tonsillectomy seemed to be more frequent than expected. Eight percent of patients reported subjective taste disorders 6 months after tonsillectomy. Fifteen patients from the initial trial, who reported taste disorders after tonsillectomy, were contacted again for this long-term follow-up. A telephone interview using the same questionnaire addressing the current self-estimate of taste function was performed. At 32 ± 10 months following surgery, two (0.9%) patients still reported suffering from taste disturbance. This long-term follow-up study shows that dysgeusia following tonsillectomy occurs in approximately 1% of patients. These data should be considered when patients are informed about complications after tonsillectomy.

Taste impairment following tonsillectomy and adenoidectomy: an unusual complication.

Tonsillectomy and adenoidectomy is a relatively safe procedure, but it is nevertheless associated with certain complications. Some of these include throat pain, otalgia, dehydration, hemorrhage, nasopharyngeal stenosis, velopharyngeal insufficiency, burns, soft-tissue injury, dentomandibular trauma, atlantoaxial subluxation, and respiratory compromise. One unusual complication is altered taste. To the best of the author's knowledge, only 29 cases of altered taste associated with palatine tonsillectomy have been previously reported in the literature since 1966. In this article, the author reports a new case and discusses the features of this unlikely complication.

[Impaired gustatory sensitivity of the tongue to table salt as a risk factor of arterial hypertension].

The study included 630 patients with verified diagnosis of arterial hypertension (AH) in whom 24 hr AP monitoring was performed, threshold gustatory sensitivity of the tongue to table salt (TGS) measured, and habit to add salt to the cooked food evaluated. Measurement of Na in daily urine of 442 patients was followed by estimation of salt consumption. The results were compared with those obtained in 100 patients with newly diagnosed AH. The control group comprised 288 subjects. TGS in AH patients was significantly higher than in controls and directly related to clinical features of the disease, high AP values, age, smoking habits, hypercholesterolemia, abdominal-type obesity, and hereditary predisposition. TGS positively correlated with daily urinary excretion of NaCl (r = 0.4-0.7; p < 0.05-0.01). High TGS decreased under effect of hypotensive therapy.

Salivary dehydroepiandrosterone (DHEA) levels in patients with the complaint of burning mouth: a case-control study.

OBJECTIVE: This study was conducted to evaluate salivary dehydroepiandrosterone (DHEA) levels, salivary flow rate (SFR), depression, and hopelessness in patients with the complaint of burning mouth (BM). STUDY DESIGN: Thirty female patients with BM and 30 age-matched control women without any complaint of burning mouth were enrolled. After anamnesis and oral examination, the salivary flow rate was determined. Depression and hopelessness were evaluated by the application of inventories. Two saliva samples were collected for DHEA analysis. RESULTS: Dysgeusia (P = .045) and xerostomia (P = .003) were significantly higher in the BM group. The BM patients showed significantly lower salivary flow rate, both under stimulation (P = .001) and at rest (P < .001). Significant differences between the groups were not found in the depression (P = .416) or hopelessness (P = .597) scores. The BM group revealed significantly lower salivary DHEA levels in the morning samples (P = .003). CONCLUSION: Patients with BM exhibit decreased morning salivary DHEA as well as dysgeusia and hyposalivation more frequently than control subjects. Additional investigations are needed to clarify this association.

Taste change following cochlear implantation.

Taste change is a well documented but under emphasised complication of middle ear surgery and is usually related to damage to the chorda tympani nerve (CTN). However, the taste outcomes following cochlear implantation have not been previously recorded. One hundred and forty one patients who had received cochlear implants between January 1997 and April 2006 were questioned using a postal survey regarding changes in the sense of taste following cochlear implantation. Sixty seven per cent of questionnaires were returned. Forty three patients (45%) experienced changes in taste following their surgery. Eighteen patients (19%) said that their symptoms had not resolved by the end of the follow up period (mean 51 months). CTN division produced taste change in 86%. Fifty per cent of patients who had CTN preservation developed taste change, presumably related to occult trauma to the nerve. The difference in the number of patients describing taste change in the two groups was statistically significant (p < 0.05). Resolution of symptoms took a mean of 20 weeks. For those patients in whom taste change was noted, resolution of symptoms was more likely if the CTN was divided rather than preserved although the difference was not statistically significant (p < 0.5). This may reflect neuronal injury during surgery which then fails to heal normally. These results are comparable to taste outcomes in patients undertaking middle ear surgery for non-inflammatory disease such as stapedectomy. The symptoms can be extremely troublesome and may not resolve with time. Careful consideration of the CTN intra-operatively is recommended and in the event of injury, the taste outcome may be better if the nerve is divided rather than left in situ but damaged. These findings have significant implications for patients as bilateral implantation becomes more commonplace.

Concurrence of non-myasthenic symptoms with myasthenia gravis.

Myasthenia gravis (MG) is a disease that is known to be accompanied by various complications. But the relationship between these complications and MG and the treatment for these complications still partly remain unknown. We report two cases of MG with unusual complications. The first one is a case of a 72-year-old woman with lingual dyskinesia, and the second is a 28-year-old man with dysgeusia. Both symptoms improved in parallel after the treatment of MG. Here we report these cases and review similar cases in the literature.