Study of the Evolution of Olfactory Disorders in Patients With Persistent Loss of Smell Following COVID-19

Prospective monocentric descriptive study. Evaluation of COVID-19 patients with persistent loss of smell during 2 visits at 1 year intervals (V1 and V2).

V1 :The following examinations will be carried out specifically for the research.

• Clinical examination;
• Blood sampling;
• Recording of olfactory evoked potentials;
• Neurological examination and neuropsychological assessment;

V2 :

All examinations performed at V1 will be repeated at V2.

If the following examinations are not carried out during care within 3 weeks of V2, they will be carried out as part of the research during this V2 visit.

• Nasal endoscopy ;
• Assessment of olfactory and gustatory functions.

The following explorations will be carried out:

• Passing of two olfactory and gustatory scales; Olfactory and gustatory disorders will be quantified using two scales, the visual analogue scale VAS and the modified TSS;
• Sniffin Stick test.

In addition, MRI data from clinical care will be collected.

Inclusion criteria

• Adults < 55 years
• History of symptomatic COVID over 1 year +/- 4 months with a positive PCR diagnosis of SARS-CoV-2
• Olfactory complaint
• Able to understand simple questionnaires in French.
• Subject covered by French Social Security (except for Aide Médicale d'Etat).

Exclusion criteria

• Contraindication to nasal swabbing (for morphological reasons, haemostasis disorders, taking aspirin in the 15 days prior to swabbing or anticoagulants, contraindications to the use of a local anaesthetic such as a history of allergy to local anaesthetics or any other reasons judged by the clinical investigator)
• To have been placed in the intensive care unit following COVID-19.
• Known previous nasal-sinus pathology.
• History of psychiatric pathology according to DSM IV criteria, ischaemic, neoplastic, inflammatory, infectious or neurodegenerative (meningitis, encephalopathy, encephalitis, stroke, neurodegenerative disease) known or suspected.
• History of loss of sense of smell prior to COVID infection.
• Patient affiliated to the Aide Médicale d'Etat.
• Person deprived of liberty by judicial or administrative decision, or subject to legal protection.