Chemotherapy A major cause of<unk>  is chemotherapy for cancer. Chemotherapy often induces damage to the oral cavity, resulting in oral mucositis, oral infection, and salivary gland dysfunction. Oral mucositis consists of inflammation of the mouth, along with sores and ulcers in the tissues. Healthy individuals normally have a diverse range of microbial organisms residing in their oral cavities; however, chemotherapy can permit these typically non-pathogenic agents to cause serious infection, which may result in a decrease in saliva. In addition, patients who undergo radiation therapy also lose salivary tissues. Saliva is an important component of the taste mechanism. Saliva both interacts with and protects the taste receptors in the mouth. Saliva mediates sour and sweet tastes through bicarbonate ions and glutamate, respectively. The salt taste is induced when sodium chloride levels surpass the concentration in the saliva. It has been reported that 50% of chemotherapy patients have suffered from either<unk>  or another form of taste impairment. Examples of chemotherapy treatments that can lead to<unk>  are cyclophosphamide, cisplatin, vismodegib, and etoposide. The exact mechanism of chemotherapy-induced<unk>  is unknown. Taste buds Distortions in the taste buds may give rise to<unk> . In a study conducted by Masahide Yasuda and Hitoshi Tomita from Nihon University of Japan, it has been observed that patients suffering from this taste disorder have fewer microvilli than normal. In addition, the nucleus and cytoplasm of the taste bud cells have been reduced. Based on their findings,<unk>  results from loss of microvilli and the reduction of Type III intracellular vesicles, all of which could potentially interfere with the gustatory pathway. Radiation to head and neck also results in direct destruction of taste buds, apart from effects of altered salivary output. Zinc deficiency Another primary cause of<unk>  is zinc deficiency. While the exact role of zinc in<unk>  is unknown, it has been cited that zinc is partly responsible for the repair and production of taste buds. Zinc somehow directly or indirectly interacts with carbonic anhydrase VI, influencing the concentration of gustin, which is linked to the production of taste buds. It has also been reported that patients treated with zinc experience an elevation in calcium concentration in the saliva. In order to work properly, taste buds rely on calcium receptors. Zinc “is an important cofactor for alkaline phosphatase, the most abundant enzyme in taste bud membranes; it is also a component of a parotid salivary protein important to the development and maintenance of normal taste buds.” Drugs There are also a wide variety of drugs that can trigger<unk> , including zopiclone, H1-antihistamines, such as azelastine and emedastine. Approximately 250 drugs affect taste. The sodium channels linked to taste receptors can be inhibited by amiloride, and the creation of new taste buds and saliva can be impeded by antiproliferative drugs. Saliva can have traces of the drug, giving rise to a metallic flavor in the mouth; examples include lithium carbonate and tetracyclines. Drugs containing sulfhydryl groups, including penicillamine and captopril, may react with zinc and cause deficiency. Metronidazole and chlorhexidine have been found to interact with metal ions that associate with the cell membrane. Drugs that act by blocking the renin - angiotensin - aldosterone system, for example by antagonizing the angiotensin II receptor (as eprosartan does), have been linked to<unk> . There are few case reports claiming calcium channel blockers like Amlodipine also cause dysguesia by blocking calcium sensitive taste buds. Pregnancy Changes in hormone levels during pregnancy, such as estrogen, can affect the sense of taste. A study found that 93 percent of pregnant women reported some change in taste during pregnancy. Miscellaneous causes Xerostomia, also known as dry mouth syndrome, can precipitate<unk>  because normal salivary flow and concentration are necessary for taste. Injury to the glossopharyngeal nerve can result in<unk> . In addition, damage done to the pons, thalamus, and midbrain, all of which compose the gustatory pathway, can be potential factors. In a case study, 22% of patients who were experiencing a bladder obstruction were also suffering from<unk> .<unk>  was eliminated in 100% of these patients once the obstruction was removed. Although it is uncertain what the relationship between bladder relief and<unk>  entails, it has been observed that the areas responsible for urinary system and taste in the pons and cerebral cortex in the brain are close in proximity.<unk>  often occurs for unknown reasons. A wide range of miscellaneous factors may contribute to this taste disorder, such as gastric reflux, lead poisoning, and diabetes mellitus. A minority of pine nuts can apparently cause taste disturbances, for reasons which are not entirely proven. Certain pesticides can have damaging effects on the taste buds and nerves in the mouth. These pesticides include organochloride compounds and carbamate pesticides. Damage to the peripheral nerves, along with injury to the chorda tympani branch of the facial nerve, also cause<unk> . A surgical risk for laryngoscopy and tonsillectomy include<unk> . Patients who suffer from the burning mouth syndrome, most likely menopausal women, are often suffering from<unk>  as well. Normal function The sense of taste is based on the detection of chemicals by specialized taste cells in the mouth. The mouth, throat, larynx, and esophagus all have taste buds, which are replaced every ten days. Each taste bud contains receptor cells. Afferent nerves make contact with the receptor cells at the base of the taste bud. A single taste bud is innervated by several afferent nerves, while a single efferent fiber innervates several taste buds. Fungiform papillae are present on the anterior portion of the tongue while circumvallate papillae and foliate papillae are found on the posterior portion of the tongue. The salivary glands are responsible for keeping the taste buds moist with saliva. A single taste bud is composed of four types of cells, and each taste bud has between 30 and 80 cells. Type I cells are thinly shaped, usually in the periphery of other cells. They also contain high amounts of chromatin. Type II cells have prominent nuclei and nucleoli with much less chromatin than Type I cells. Type III cells have multiple mitochondria and large vesicles. Type I, II, and III cells also contain synapses. Type IV cells are normally rooted at the posterior end of the taste bud. Every cell in the taste bud forms microvilli at the ends.
Dysgeusia
Dysmelia
Misophonia
Anotia
Hyperorgasmia
Diplophonia
Dysgraphia
Lonomia