The temporal course of COVID-19 anosmia and relation to other clinical symptoms.

OBJECTIVE: This study aimed to define the clinical course of anosmia in relation to other clinical symptoms. METHODS: 135 patients with COVID-19 were reached by phone and subsequently included in the study. Olfactory functions were evaluated using a questionnaire for assessment of self-reported olfactory function. Patients were divided into four subgroups according to the presence of olfactory symptoms and temporal relationship with the other symptoms: group1 had only olfactory complaints (isolated, sudden-onset loss of smell); group2 had sudden-onset loss of smell, followed by COVID-19 related complaints; group3 initially had COVID-19 related complaints, then gradually developed olfactory complaints; and group4 had no olfactory complaints. RESULTS: In total, 59.3% of the patients interviewed had olfactory complaints during the disease course. The olfactory dysfunction severity during COVID-19 infection was significantly higher in group1 compared to groups 2 and 3. In groups1-3, the odor scores after recovery from COVID-19 disease were significantly lower compared to the status prior to disease onset. The residual olfactory dysfunction was similar between groups1 and 2, but was more evident than group3. Mean duration for loss of smell was 7.8 ± 3.1 (2-15) days. Duration of loss of smell was longer in groups1 and 2 than in group3. Odor scores completely returned back to the pre-disease values in 41 (51.2%) patients with olfactory dysfunction. Rate of complete olfactory dysfunction recovery was higher in group3 compared to groups1 and 2. CONCLUSION: In isolated anosmia cases, anosmia is more severe, and complete recovery rates are lower compared to the patients who have other clinical symptoms. LEVEL OF EVIDENCE: Level 4.

Ear nose throat-related symptoms with a focus on loss of smell and/or taste in COVID-19 patients.

PURPOSE: To determine the frequency and severity of general and ear nose throat (ENT)- related symptoms, especially smell and/or loss of sense of taste (STL) in COVID-19 disease, as well as to investigate the recovery process of STL. MATERIALS AND METHODS: Patients with a positive COVID-19 diagnosis were given a questionnaire consisting of general questions (age, sex, date of symptoms, smoking history, concomitant diseases), questions about the most obvious symptom at presentation (one option only), the severity and frequency of symptoms (general and ENT), and STL (recovery time and degree of recovery). RESULTS: The study population consisted of 172 patients, 18-65 years old (mean age, 37.8 ± 12.5 years; 51.2% female; 76.2% nonsmokers). Cough (n = 30, 17.4%) and loss of sense of smell (n = 18, 10.4%) were the most obvious general and ENT symptoms, respectively. Eighty-eight patients (51.2%) reported loss of sense of smell, and 81 patients (47.1%) reported loss of sense of taste. The mean recovery times for loss of sense of smell and loss of sense of taste were 8.02 ± 6.41 and 8.20 ± 7.07 days, respectively. The loss of sense of smell and loss of sense of taste were the unique symptoms in four (4.54%) and one (1.23%) patients, respectively. CONCLUSION: STL is a common symptom in COVID-19 and may be the first and/or only symptom of this disease. In patients presenting with STL complaints, surveillance for possible COVID-19 disease and screening tests will facilitate the struggle against the disease.