A Case of Cronkhite-Canada Syndrome Whose Major Complaint,Taste Disturbance,Was Improved by Zinc Therapy

A patient whose major complaint was taste disturbance and who was diagnosed as having Cronkhite-Canada syndrome was prescribed zinc sulfate. Improvement in taste disturbance was noted after 3 weeks of treatment, followed by gradual improvement in skin and gastrointestinal symptoms. Cronkhite-Canada syndrome can be considered a zinc-deficiency disorder caused by gastrointestinal polyposis.     

Taste disturbance after stapes surgery: an evaluation of frequency,severity, duration,and quality-of-life

Conclusion: The incidence of taste disturbance after stapes surgery is high (61.9%), whereas the majority (94.8%) recovers within 1 year. More severe surgical nerve trauma caused more disturbance, implying that the nerve should be handled carefully during surgery.

Objectives: Patients operated on for otosclerosis seem more often to complain about post-operative taste disturbance than those operated on for chronic otitis media, although the chorda tympani nerve more seldom becomes maltreated in stapedotomy. These observations seem paradoxical. It is unclear to what extent a post-operative taste disturbance affects the quality-of-life. This study aims to shed light on the occurrence of post-operative taste disturbances, on possible prognostic factors, and to what extent post-operative taste disturbance impairs the quality-of-life.

Methods: One hundred and thirty-four adults undergoing primary stapedotomy were included. Questionnaires on taste disturbance and quality-of-life (SF-36) were answered before and after surgery, until 1 year post-operatively.

Results: Eighty-three (61.9%) study persons reported post-operative taste disturbance. Seven (5.2%) reported persisting disturbance at 1 year. Surgically more traumatized chorda tympani nerves correlated with more severe taste disturbance post-operatively than less traumatized. Taste disturbance at 1 year post-operatively correlate with a decrease of the physical function domain in the SF-36.     

Clinical study of flavor disturbance

OBJECTIVE: We have observed that, in cases of smell loss, patients often complain of taste loss as well even though they actually have normal gustatory acuity according to gustatory tests; we have defined such symptoms as "flavor disturbance". The clinical features of flavor disturbance are reported in this paper. MATERIAL AND METHODS: A total of 297 patients (99 males, 198 females; mean age 55.5 years) were treated for olfactory disturbance at the hospital of Hyogo College of Medicine between July 1995 and August 2001. Sixty-six out of 297 patients (22.5%) also experienced taste disturbance, and 49 of these 66 cases were evaluated by means of smell and taste tests. These 49 patients who complained of taste and smell loss were classified into two groups according to the results of their smell and taste tests. Patients who only complained of olfactory disturbance were also reviewed. RESULTS: There was no relationship between the severity of olfactory disturbance and the degree of flavor disturbance. The incidence of flavor disturbance was high in patients with sudden olfactory disturbance after upper respiratory tract infection or head trauma and low in those with slowly progressive olfactory disturbance. The symptoms of flavor disturbance improved regardless of whether smell was improved or not. CONCLUSIONS: The patients with flavor disturbance tended to misrecognize that they had taste loss because of sudden smell loss, and there were more of these cases than we expected. When patients with smell and taste loss are treated, flavor disturbance should also be considered.     

Course of Recovery from Taste Receptor Disturbance

The course of recovery from taste receptor disturbance was studied in 119 patients with moderate-to-severe taste receptor disturbance that was cured or improved with zinc therapy. Taste receptor disturbance was idiopathic in 45 patients, drug-induced in 38 and due to zinc deficiency in 36. Recovery of taste, evaluated by filter paper disk testing and electrogustometry, followed 1 of 3 patterns: (i) in 54 (45.4%) of the 119 cases, taste improved simultaneously in the anterior (innervated by the chorda tympani nerve) and posterior (innervated by the glossopharyngeal nerve) portions of the tongue; (ii) in 53 (44.5%) of the cases, taste improved in the posterior portion first; and (iii) in 12 (10.1%) of the cases, taste improved in the anterior portion first. Zinc therapy was more effective in patients with the "posterior" pattern of recovery, and these patients also recovered the ability to sense sweet and bitter tastes earlier than other tastes. These results indicate that recovery of taste begins on the posterior portion of the tongue, which has an abundance of taste buds. The results of electrogustometry were not helpful in assessing recovery from taste disturbance, but testing for taste using the filter paper disk method on the posterior portion of the tongue was useful for identifying the onset of recovery.     

Course of recovery from taste receptor disturbance

The course of recovery from taste receptor disturbance was studied in 119 patients with moderate-to-severe taste receptor disturbance that was cured or improved with zinc therapy. Taste receptor disturbance was idiopathic in 45 patients, drug-induced in 38 and due to zinc deficiency in 36. Recovery of taste, evaluated by filter paper disk testing and electrogustometry, followed 1 of 3 patterns: (i) in 54 (45.4%) of the 119 cases, taste improved simultaneously in the anterior (innervated by the chorda tympani nerve) and posterior (innervated by the glossopharyngeal nerve) portions of the tongue; (ii) in 53 (44.5%) of the cases, taste improved in the posterior portion first; and (iii) in 12 (10.1%) of the cases, taste improved in the anterior portion first. Zinc therapy was more effective in patients with the "posterior" pattern of recovery, and these patients also recovered the ability to sense sweet and bitter tastes earlier than other tastes. These results indicate that recovery of taste begins on the posterior portion of the tongue, which has an abundance of taste buds. The results of electrogustometry were not helpful in assessing recovery from taste disturbance, but testing for taste using the filter paper disk method on the posterior portion of the tongue was useful for identifying the onset of recovery.     

Treatment outcome in patients with taste disturbance

The importance of taste has been recently evaluated from the standpoint of quality of life, but few reports exist on the clinical status of taste disturbance. We classified taste disturbance by cause and studied the effect of treatment and recovery duration. Subjects were 321 patients with taste disturbance, i.e., 131 men and 190 women (mean age: 59.9 years). Electrogustometry (EGM) and filter paper disks (FPD) were used to assess taste function in all subjects. We also asked them all about the degree of symptoms using visual analog scale (VAS). Statistical analysis was done using the unpaired t-test, with p<0.05 considered significant. Patients were treated with zinc sulfate, ferrotherapy, herbal medicine, and minor tranquilizers. Causes of taste disturbance were classified into idiopathic, post-common-cold, drug-induced, psychogenic, constitutional, and iron deficiency. Idiopathic taste disturbance was the commonest cause (125 cases, 38.9%), followed by drug-induced (62 cases, 19.3%), and post common cold (38 cases, 11.8%). Drug induced and psychogenic taste disturbance have increased. Recovery from symptoms was 79/103 (76.7%) in idiopathic taste disturbance, 24/33 (72.7%) in post-common-cold, and 14/17 (82.4%) in iron deficiency. Recovery took 22.2 weeks. Recovery was 32/50 cases (62.4%) in drug induced, taking 48 weeks. For all causes, EGM and FPD results were not associated with the degree of symptoms. Both tests tended to show delayed improvement compared to symptoms. Cases taking more than 6 months from symptom onset to medical examination showed significantly lower improvement and longer recovery time than those taking 6 months on less (p = 0.04).     

治疗阻塞性睡眠呼吸暂停低通气综合征的咽成形术对嗅觉和味觉的影响

目的:观察治疗阻塞性睡眠呼吸暂停低通气综合征(OSAHS)的咽成形术对嗅、味觉的影响。方法:总结2005年4月~12月行咽成形术的39例患者中有嗅、味觉改变的主诉情况。结果:4例诉术后味觉改变,其中1例诉同时有嗅觉改变。例1嗅觉减退,酸和咸感觉丧失,2个月后部分恢复,对甜感觉过敏;例24种味觉均减退;例3对酸的感觉过度敏感;例4感痰中有酸和苦的感觉,属味幻觉。味觉改变的发生率达10%。结论:嗅觉和味觉的改变可能是咽成形术的并发症,影响患者的生活质量,必须给予重视,术前应向患者交代清楚,以免引起不必要的医疗纠纷。术中尽可能避免损伤味觉功能,如果发生嗅、味觉损伤,术后需给予处理。     

Taste and olfactory disturbances after treatment for acne with isotretinoin,a 13-cis-isomer of retinoic acid

Summary We report an olfactory disturbance after acne treatment with isotretinoin. A disturbance in taste was also reported by the patient. Examination of the nose showed no pathological findings. A CT scan was done to exclude a tumor or a lesion at the lamina cribrosa. Taste and smell examinations were performed and verified the lost qualities.     

Taste disturbance after tonsillectomy and laryngomicrosurgery

OBJECTIVE: To investigate the incidence of taste disturbance after tonsillectomy and laryngomicrosurgery. STUDY DESIGN: A prospective study. METHODS: Thirty-five consecutive patients underwent tonsillectomy with electric coagulator at Kanebo Memorial Hospital from September 2002 to May 2004. Another 35 consecutive patients underwent laryngomicrosurgery in a routine way during the same period. Both procedures were performed by two experienced doctors. The postoperative taste function was evaluated with questionnaire, electrogustometry (EGM), and serum levels of Zn, Cu and Fe. RESULTS: After tonsillectomy, 3/35 patients (8.6%) complained of taste disturbance, due to the pressure on the tongue in two, and Zn deficiency after lack of intake in one. All three patients recovered taste within 1.5 months. None of our patients had taste disturbance due to surgical insult of the lingual branch of the glossopharyngeal nerve. After laryngomicrosurgery, only one patient (2.9%) complained of taste disturbance with elevation of the EGM threshold that resulted from the pressure on the tongue. In addition, abnormal sensation in the tongue occurred in 9 cases (25.7%) after tonsillectomy and in 2 cases (5.7%) after laryngomicrosurgery, and feeling of thirst occurred in 12 cases (34.3%) and in 8 cases (22.9%), respectively. CONCLUSION: Taste disturbance occurs in few cases when experienced surgeons perform tonsillectomy or laryngomicrosurgery. However, it is recommended to inform the patients of the potential postoperative complications such as taste disturbance and abnormal sensation of the tongue.     

The effect of early division of the chorda tympani on gustatory function

This study was undertaken to assess dysgeusia in patients who have undergone middle ear surgery for chronic suppurative otitis media (CSOM) when the surgeon's practice was to cleanly divide the chorda tympani without prior manipulation, if it in any way hindered operative access or the aims of surgery. We wanted to determine whether lower rates of taste disturbance might be obtained by early, clean division of the nerve. We followed 110 patients prospectively and asked them to complete a postoperative dysgeusia questionnaire 1 year after surgery. The "cut nerve" group included 81 patients, and the "uncut nerve" group included 29 patients. In the uncut group, the nerve was untouched or underwent minimal handling. In the cut nerve group, 68% of patients had no taste disturbance after surgery; 4% of patients in this group had ongoing symptoms at 1 year postoperatively. In the uncut nerve group, 67% were asymptomatic, while 11% had ongoing taste disturbance at 1 year. Statistical analysis of symptoms beyond 1 year showed a mean difference of 7%, but this is not statistically significant (p = 0.38). These results suggest that early division of the chorda tympani without prior manipulation in patients with chronic suppurative otitis media does not result in higher rates of taste disturbance than in patients with uncut nerves. Indeed rates of taste disturbance in our cut group were lower than in the uncut group, and lower than or comparable to those seen in other studies.     

Drug-Related Taste Disturbances

Drug-induced change in taste is the second most common cause of taste disturbance among our patients, accounting for &#44 25% of cases. About 170 drugs have been associated with taste disturbances, either when used alone or in combinations. We studied the zinc-chelating capability of 20 drugs associated with taste disturbance, using the pH titration test, DC polarography, spectrophotometry and tests of intestinal absorption of zinc in the presence of these drugs. The results of these analyses and our review of the literature indicate that there are a number of possible mechanisms for drug-related taste disturbance and that zinc plays a key role.     

Drug-related taste disturbances

Drug-induced change in taste is the second most common cause of taste disturbance among our patients, accounting for approximately 25% of cases. About 170 drugs have been associated with taste disturbances, either when used alone or in combinations. We studied the zinc-chelating capability of 20 drugs associated with taste disturbance, using the pH titration test, DC polarography, spectrophotometry and tests of intestinal absorption of zinc in the presence of these drugs. The results of these analyses and our review of the literature indicate that there are a number of possible mechanisms for drug-related taste disturbance and that zinc plays a key role.     

Unusual complication of tonsillectomy: taste disturbance and the lingual branch of the glossopharyngeal nerve

Taste disturbance is an unusual complication of tonsillectomy of which there are very few reports in the literature. The possible causes of this rare complication are: (1) direct or indirect damage to the glossopharyngeal nerve or its lingual branch (LBGN), (2) lack of dietary zinc, and (3) habitual drug intake. We report a 41-year-old man, who complained of taste disturbance following tonsillectomy that was performed for chronic tonsillitis and unilateral (left) tonsillar hypertrophy. During surgery, hypertrophic tonsils were found to be sited deeply into the tonsillar bed, especially at the lower pole of the left tonsil. Pathologic examination following tonsillectomy revealed a keratinous cyst and chronic infection at the left tonsil, and lymphoid hyperplasia and chronic infection at the right tonsil. Although his complaint had been getting better, qualitative examination of his taste function revealed bilateral impairment of the sense of sweet taste on the base of his tongue two months after the surgery, and a taste disturbance of sweet taste on the left side persisted the 10th month after the surgery. His serum zinc value was normal, and he did not take any drug that could affect his sense of taste. Depending on the literature data, possible indirect damage to the LBGN was suspected as the cause of the taste disturbance. This symptom may be reversible within two years after tonsillectomy, but it can also be irreversible. Therefore, tonsillectomy should be performed with minimal trauma to the tonsillar bed, especially when there is an additional pathology extending into the lower pole, and such a patient should be informed of the risk of post-operative taste disturbance after tonsillectomy as being one of the rare complications of this surgery.     

Chorda tympani nerve function after middle ear surgery.

OBJECTIVE: To assess chorda tympani nerve function before and after different types of middle ear surgery. The hypothesis was that in cases with cholesteatoma, iatrogenic injury to the nerve results in less postoperative taste disturbance than those undergoing myringoplasty or stapedectomy. STUDY DESIGN: Prospective questionnaire study. SETTING: ENT Department of a district general hospital in England. PATIENTS: Adult patients undergoing middle ear surgery in which there would be elevation of the anulus. MAIN OUTCOME MEASURE: Patients' change in taste sensation after surgery with follow-up to demonstrate subsequent recovery. RESULTS: A significantly higher incidence of taste disturbance follows myringoplasty and stapedectomy than for procedures in which the initial diagnosis was cholesteatoma, regardless of the extent of injury sustained by the nerve. The most common complaint after chorda tympani nerve injury is of a metallic taste sensation. CONCLUSION: Despite the small patient cohort, the results support the hypothesis that iatrogenic chorda tympani nerve injury in surgery for cholesteatoma results in less postoperative taste disturbance than that for otosclerosis. This may be because the disease process of cholesteatoma renders the nerve hypofunctional. The situation after myringoplasty is less clear. A larger study may help validate these findings.     

Taste Disturbance in Two Patients after Dental Anesthesia by Inferior Alveolar Nerve Block

We report two cases of temporary taste disturbance after inferior alveolar nerve block. The first patient to present with this rare complication of anesthesia for dental surgery was a 41-year-old woman. She lost the sense of taste on the left side of her tongue after local anesthesia for treatment of a left mandibular molar and first visited our outpatient clinic complaining of taste disorder 3 months later. Electrogustometry (EGM) and filter paper disk (FPD) testing revealed a taste disturbance in the innervation area of the left chorda tympani nerve and atrophy of the fungiform papillae on the left side of the tongue was observed. Eleven months after the dental treatment, the fungiform papillae and the results of EGM were normal. The second patient, a 22-year-old woman, received local anesthetic for extraction of a right mandibular molar and subsequently developed loss of taste on the right side of the tongue. When she visited our outpatient clinic 3 months later, atrophy of the fungiform papillae on the right side was observed. Her gustatory sense began to improve 4 months after the dental surgery and was normal at 13 months. From these findings we conclude that taste disturbance on the same side as the inferior alveolar nerve block in each case was due to direct injury to the chorda tympani and lingual nerves during administration of the local anesthetic. The results of EGM and FPD testing were diagnostic: atrophy of the fungiform papillae on the same side and disappearance of taste on the same side in the intravenous taste test provided complementary diagnostic information. The outcome was satisfactory in both cases.     

Taste disturbance in two patients after dental anesthesia by inferior alveolar nerve block

We report two cases of temporary taste disturbance after inferior alveolar nerve block. The first patient to present with this rare complication of anesthesia for dental surgery was a 41-year-old woman. She lost the sense of taste on the left side of her tongue after local anesthesia for treatment of a left mandibular molar and first visited our outpatient clinic complaining of taste disorder 3 months later. Electrogustometry (EGM) and filter paper disk (FPD) testing revealed a taste disturbance in the innervation area of the left chorda tympani nerve and atrophy of the fungiform papillae on the left side of the tongue was observed. Eleven months after the dental treatment, the fungiform papillae and the results of EGM were normal. The second patient, a 22-year-old woman, received local anesthetic for extraction of a right mandibular molar and subsequently developed loss of taste on the right side of the tongue. When she visited our outpatient clinic 3 months later, atrophy of the fungiform papillae on the right side was observed. Her gustatory sense began to improve 4 months after the dental surgery and was normal at 13 months. From these findings we conclude that taste disturbance on the same side as the inferior alveolar nerve block in each case was due to direct injury to the chorda tympani and lingual nerves during administration of the local anesthetic. The results of EGM and FPD testing were diagnostic: atrophy of the fungiform papillae on the same side and disappearance of taste on the same side in the intravenous taste test provided complementary diagnostic information. The outcome was satisfactory in both cases.     

Olfactory and gustatory disturbances caused by digitalism: a case report

It is known that an overdose of digoxin causes visual disturbance, but the effect on the senses of smell and taste is not known. A case of olfactory and gustatory disturbance caused by digitalism is reported. In a 62-year-old male patient suffering from chronic digitalism, the serum digoxin level rose to 6.0 ng/ml. The patient was diagnosed not only with visual disturbance but also hyposmia and hypogeusia. The patient recovered from visual and chemosensory disturbances after the serum digoxin concentration returned to normal. Because the similarity of intracellular signal transduction between photoreceptor cells and olfactory and/or taste receptor cells is known, it is suspected that the influence of digoxin to chemosensory organs was caused by intermediation of sodium–potassium–adenosine triphosphatase (Na–K–ATPase) of the chemosensory receptor cells.     

Changes in taste bud volume during taste disturbance

On-line mapping and serial volume measurements of taste buds with confocal laser scanning microscopy provide information on the peripheral gustatory organ over time. We report the volumetric measurements of four selected fungiform papillae over 8 weeks in a 62-year-old man with taste disturbance, which was more apparent on the right than on the left side. In the two papillae on the right side, no taste buds were detected within the fungiform papillae in the sixth and eighth week. During sixth and eighth week, there was no response to the highest presented stimuli in electrogustometry (1 mA) on the right-sided tongue tip nor at the tongue edge. The morphology (shape, diameter) of the fungiform papillae on both sides remained unchanged. Comparison of the time course of the volume changes revealed differences corresponding to gustatory sensitivity. These findings suggest that the time course of volume changes indicated taste disturbance in our patient, rather than morphological changes in the fungiform papillae.