Skip to main content
OpenTrials
Recruiting

NCT Number: NCT06482138

Dysfunction of Olfaction After COVID-19 Infection: Morphological and Histomolecular Investigation

Investigation of the mechanisms of persistent SARS-CoV-2 associated olfactory dysfunction (OD) in patients with well-documented olfactory function. The investigators plan to collect olfactory cleft biopsies and cytobrushes in COVID-19 patients and controls.

Recruiting

Interested in participating?

Request Info

Key information

Conditions

Covid19 Anosmia COVID-19 Coronaviridae Infections Coronavirus Infections Infections Lung Diseases Nervous System Diseases Neurologic Manifestations Nidovirales Infections Olfaction Disorders Olfactory Dysfunction Pathological Conditions, Signs and Symptoms Pneumonia Pneumonia, Viral RNA Virus Infections Respiratory Tract Diseases Respiratory Tract Infections Sensation Disorders Signs and Symptoms Virus Diseases

Age range

18 year–70 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Cliniques Universitaires Saint-Luc, Brussels, Brussels Capital, Belgium

Loading trial locations.

About this study

An explorative prospective clinical study using human body materials of living post-COVID-19 patients with and without OD, to study the mechanisms of persisting olfactory dysfunction. Patients consult ENT specialist for medical purposes and undergo standard-of-care diagnostics and management. The collected tissues from the olfactory cleft mucosa will be analyzed using single cell RNA sequencing and RNAscope combined with immunohistochemistry.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Olfactory Dysfunction group: Presence of evident OD (Parosmia, Threshold-Discrimination-Identification (TDI)-score ≤24, Subjective abnormal quantitative olfactory function; measured by a visual analogue score (VAS) of smell impairment ≥5/10
  • Control group: No OD (TDI-score >30.5.)

Exclusion criteria

  • Presence of concomitant nasal mucosal pathology that might affect olfactory function or bias the study investigations
  • Use of anticoagulation therapy
  • Allergy to local anesthetics

Treatment and study plan

Biopsy and Cytobrush

Procedure

Collection of olfactory cleft biopsies and cytobrushes

Primary outcomes

  1. Analysis of olfactory cleft biopsies

    Time frame: From enrollment of 1 patient until analyzed, 1 month

    Morphological and histomolecular differences between OD and control patients

    • Evaluating tissue pathology:
    • Metaplasia
    • hypertrophy
    • aberrant scar formation
    • apoptosis
    • presence of inflammatory cells [H&E, CD68 and CD3 stainings, RNAscope]
    • Presence of SARS-CoV-2 RNA
    • Percentage of OSNs versus sustentacular cells; maturation of OSNs

  2. Analysis of olfactory cytobrushes

    Time frame: From enrollment of 1 patient until analyzed, 1 month

    Morphological and histomolecular differences between OD and control patients

    • Evaluating tissue pathology:
    • Metaplasia
    • hypertrophy
    • aberrant scar formation
    • apoptosis
    • presence of inflammatory cells [H&E, CD68 and CD3 stainings, RNAscope]
    • Presence of SARS-CoV-2 RNA
    • In the olfactory epithelium: percentage of OSNs versus sustentacular cells; maturation of OSNs

Interested in participating?

Recruiting

Interested in participating?

Request Info

Sponsors and collaborators

Lead sponsor

Universitaire Ziekenhuizen KU Leuven

Other

Collaborators

  • Max Planck Research Unit for Neurogenetics
  • University Hospital Carl Gustav Carus
  • University Hospital, Geneva
  • University of Zurich

Registry information

Official study title

Dysfunction of Olfaction After SARS-CoV-2 Infection: Morphological and Histomolecular Investigation of Olfactory Cleft Biopsies and Cytobrushes

Acronym: DysOSMIC

Important dates

Study start
2024
Primary completion
2026
Study completion
2026
First posted
Jul 1, 2024
Registry last updated
May 6, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.