Can photobiomodulation restore anosmia and ageusia induced by COVID-19? A pilot clinical study.

Along with other COVID-19 clinical manifestations, management of both olfactory and gustatory dysfunction have drawn a considerable attention. Photobiomodulation (PBM) has emerged to be a possible effective therapy in restoring taste and smell functionality, but the evidence is scarce. Hence, the present pilot study is aimed to evaluate the effectiveness of intranasal and intraoral PBM administrations in management of anosmia and ageusia respectively. Twenty Caucasian subjects who diagnosed with anosmia and ageusia were recruited. Visual analogue scale was utilised to evaluate patients' self-reported for both olfactory and gustatory functionality. The laser-PBM parameters and treatment protocols for anosmia and ageusia were as follows respectively: 660 nm, 100 mW, two points intranasally, 60 J/session, 12 sessions; dual wavelengths (660 nm and 808 nm), 100 mW, three points intraorally, 216 J/session, 12 sessions. Our results showed a significant functionality improvement of both olfactory and gustatory functionality. Extensive studies with large data and long-term follow-up period are warranted.

Anosmia and Ageusia: Not an Uncommon Presentation of COVID-19 Infection in Children and Adolescents.

Since the emergence of a cluster of viral pneumonia cases in Wuhan, Hubei Province, People's Republic of China, at the end of December 2019, caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2), a novel coronavirus also known as "coronavirus disease 2019 (COVID-19)," as of 7 April 2020, more than 1,214,466 cases of COVID-19 have been reported in more than 200 countries and territories, resulting in more than 67,767 deaths. The disease was recognized by World Health Organization (WHO) as a pandemic on 11 March 2020. Published reports of adult patients with COVID-19 infection described symptoms including fever, cough, fatigue, sputum production, headache, dyspnea and diarrhea. Children usually showed milder respiratory symptoms or were asymptomatic, while loss of taste or sensation of smell were seldom reported. In this paper, we report three cases of pediatric patients with COVID-19 infection who presented with anosmia and/or ageusia.

Recurrent hypogeusia in a patient with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).

Hypogeusia, a condition with diminished sense of taste, is caused by several conditions, including zinc deficiency and as a side-effect of drugs, but is not common in neurological disorders. A 55-year-old Japanese man with a 30-year history of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) presented with hypogeusia during hospitalization for a recurrence of CIDP. The hypogeusia improved after treatment with high-dose intravenous methylprednisolone (HIMP). Two years later, hypogeusia developed again. A complete taste deficit was revealed by a filter paper test. Brain MRI showed enhancement of the bilateral facial nerve ganglia. Hypogeusia was partially ameliorated after extensive immunosuppressive therapy with repeated HIMP and plasma exchange. Improvement was more prominent in the area innervated by the chorda tympani nerve than that innervated by the glossopharyngeal nerve. To our knowledge, this is the first report of recurrent hypogeusia, which might be caused by cranial nerve injury associated with CIDP.

[Dysfunction of the chemical senses smell and taste]. / Störungen des Riechens und Schmeckens.

Dysfunction of the senses of taste and smell may strongly affect our lives. During the last years reliable techniques for the standardized investigation of the 2 senses have been introduced to clinical routine. These techniques are highly standardized and can be easily used, for example, for quality control before and after surgery. Although there are proven therapeutic approaches to taste or smell loss, by far not all patients can be helped. New ideas need to tested within rigorous double-blind studies. The regenerative capacity within the chemical senses provides a major basis for hopes on therapeutic success.

Biology of taste buds and the clinical problem of taste loss.

Taste buds are the anatomical structures that mediate the sense of taste. They comprise taste cells and nerve fibers within specialized epithelial structures. Taste cells are traditionally described by histologic methods as basal, dark, intermediate, and light cells, with the nerve fibers surrounding and infiltrating the taste buds. By means of immunohistochemical methods, taste cells and gustatory nerve fibers can be classified in functional groups based on the expression of various cell adhesion molecules and other proteins. When taste buds become damaged, the loss of the ability to taste results. This loss is not uncommon and can impact health and quality of life. Patients who receive radiation therapy for head and neck cancer often experience taste loss, which leads to compromised nutritional intake and a worse outcome than patients who do not experience taste loss. The mode of radiation damage to taste cells and nerve fibers has been investigated using cell adhesion molecules, synaptic vesicle proteins, and other cell markers. The light and intermediate cells are preferentially affected by ionizing radiation, whereas the nerve fibers remain structurally intact. Experimental studies of radiation-induced taste loss are performed via a unique animal/human model.

[Disorders of smell and taste. Standard and recent methods in diagnosis and therapy]. / Riech- und Schmeckstörungen Bewährtes und Neues zu Diagnostik und Therapie.

Compared to disorders of the ears and eyes, diseases of smell and taste seem to be far less outstanding: however, the unimpaired perception of odours and flavours comprises an important part of our well-being, as can be seen in the perfume industry or in drinking and eating habits. The ENT-specialist covers organic causes of these senses, as he has the tools to explore and treat in the depth of the nasal and oral cavities. The "Arbeitsgemeinchaft Olfaktologie/Gustologie der Deutschen Gesellschaft für Hals-Nasen-Ohrenheilkunde, Kopf- und Halschirurgie" therefore is in process of establishing a new set for a standardised smell and taste test, which is based in part on the sniffin'sticks, which were developed by Prof. Kobal, Erlangen. The examination procedure of nasal and oral chemosensory performance requires a high test-retest reliability and an efficiency comparable to internationally established measurements in order to render valid results in diagnostic and therapeutic procedures. The new test kit with the sniffin'sticks is presented in this paper, followed by an overview on some disorders of smell and taste perception and proposals for actual therapeutic procedures.

[Ageusia as the aftereffect of oxyfedrine use]. / Ageusia jako nastepstwo ubocznego dzialania oksyfedryny.

Out of oxyfedrine++ side effects known up to the present (mild agitation, stupor, heat sensation, pains in the epigastrium++, skin allergy) 24 cases of ageusia appearing usually after 4 weeks of treatment with oxyfedrine++ were presented. Disturbances of taste are found to be unpleasant for patients, and result in remarkable exacerbation of their general feeling. The complaints subside completely after finishing treatment, and the time of taste disorder withdrawal is prolonged according to the time of oxyfedrine++ treatment.

Oral complications of cancer radiotherapy.

Injury to surrounding tissues during radiotherapy for oral cancer can have devastating physical and psychologic consequences for the patient. Oral complications include xerostomia, dental decay, mucositis, taste loss, osteoradionecrosis, infection, and trismus. In many instances, these problems can be eradicated or controlled with appropriate treatment.