Characterization of Bacterial and Mycosis Skin Flora in Seborrheic Macular Hypopigmentation - Microbiome (Microbiome_SHM)

Characterization of Bacterial and Mycosis Skin Flora in Seborrheic Macular Hypopigmentation - Microbiome_SHM

Hypopigmented skin changes are commonly encountered by dermatologists. A new dermatological entity was identified as scattered, hypopigmented oval-shaped macules and patches distributed mostly in seborrheic area of the face and of the trunk in dark skinned individuals. This patterned presentation of hypopigmentation was first described in the literature under the name of hypochromic vitiligo or vitiligo minor. Nerveless, histopathological patient's specimens analyzed by Krueger et al. clearly highlight that there is no tangible causal correlation with a diagnosis of vitiligo. They propose to rename this entity to Seborrheic Macular Hypopigmentation (SMH). The etiopathology of this dermatosis is still unknown preventing to propose any satisfactory treatment for this disfiguring affection.The objective of this study is to analyze the bacterial and fungal skin microbiome on hypochromic lesions of SMH compared to the surrounding non-lesional skin of the same patients and to healthy volunteers

Study Overview

• Status: Recruiting
• Conditions: Hypopigmentation
• Intervention / Treatment: Other: Skin's lesion patients; Other: Skin's lesion vulunteers

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Thierry Passeron, PhD; Phone Number: +33492036488; Email: passeron.t@chu-nice.fr
• Study Contact Backup: Name: Emmanuelle Pradelli; Phone Number: +33492036488; Email: pradelli.e@chu-nice.fr

Study Locations

• France
  • Colmar, France, 68024
    • Recruiting
    • Hôpital Louis Pasteur, hôpitaux Civils de Colmar
    • Contact: Antoine Mahé, PHD; Phone Number: +33389124158; Email: antoine.mahe@ch-colmar.fr
    • Principal Investigator: Antoine MAhé, PhD
  • Alpes-Maritimes
    • Nice, Alpes-Maritimes, France, 06200
      • Recruiting
      • CHU de Nice - Hôpital de l'Archet
      • Contact: Thierry Passeron, PhD; Phone Number: +33492036488; Email: passeron.t@chu-nice.fr
      • Principal Investigator: Thierry Passeron, PhD
  • Ile de France
    • Paris, Ile de France, France, 75010
      • Recruiting
      • Hôpital Saint-Louis - APHP
      • Contact: Christelle Comte; Phone Number: 0650728909; Email: dr.ch.comte@gmail.com
      • Principal Investigator: Christelle Comte

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Female and male patients ≥ 18 years of age
2. Clinical diagnosis of SMH with lesion of the face
3. Written informed consent obtained before any assessment is performed
4. Affiliation with a social security scheme
5. Physical and psychological ability to participate

Exclusion Criteria:

1. Use of systemic antibiotics or any systemic antifungal treatments within 4 weeks before the inclusion visit
2. Use of topical antibiotics or any topical antifungal treatments on the face within 2 weeks before the inclusion visit
3. Use of any topical cream, gel, serum or ointment within 2 days before the inclusion visit
4. Laser, radiofrequency, peeling or any other procedure on the face in the past 3 months before the inclusion visit
5. Vulnerable patients: minors, patients under guardianship or curatorship, pregnant or breast-feeding women

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Patients; The study population will consist of adult subjects (≥ 18 years) with Seborrheic Macular Hypopigmentation.	Other: Skin's lesion patients; Skin swabs will be obtained from the patient's facial lesional (FLS) and perilesional sites (FPS) using a sterile cotton swab. The microbiota of the same anatomical face regions will be collected on volunteers, once the 10 SMH patients have been enrolled. The swab is premoistened in a specific cocktail solution and rubbed onto the skin surface for 45sec. The pressure during the sampling involves rubbing the area of interest with a smear over the entire zone. The skin reddens slightly under the exerted pressure.
Other: Vulunteers; Volunteers will be included once the required number of SMP patients has been attained. Volunteers are going to be recruited only at the coordinator center, the CHU of Nice. Recruitment will be communicated to medical and/or Inserm staff, via an announcement in the respective departments.	Other: Skin's lesion vulunteers; Skin swabs will be obtained from the patient's facial lesional (FLS) and perilesional sites (FPS) using a sterile cotton swab. The microbiota of the same anatomical face regions will be collected on volunteers, once the 10 SMH patients have been enrolled. The swab is premoistened in a specific cocktail solution and rubbed onto the skin surface for 45sec. The pressure during the sampling involves rubbing the area of interest with a smear over the entire zone. The skin reddens slightly under the exerted pressure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The bacterial skin microbiome of SMH patients vs voluntheers	For each sample, the bacterial profiles determined by real time PCR, will be described and compared as follows: seborrheic macular hypopigmented lesions versus same anatomic area in healthy volunteers.	at baseline

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The bacterial skin microbiome of SMH patients compare to the non-lesional surrounded skin of the same patients.	For each sample, the bacterial profiles determined by real time PCR, will be described and compared as follows: intra-individual hypochromic macula lesions versus perilesional areas located at least 1cm away from any hypopigmented macules.	at baseline

Collaborators and Investigators

• Sponsor: Centre Hospitalier Universitaire de Nice
• Investigators: Principal Investigator: Thierry Passeron, PhD, CHU de Nice, Service de Dermatologie

Study record dates

Study Major Dates

• Study Start (Actual): June 25, 2025
• Primary Completion (Estimated): January 25, 2026
• Study Completion (Estimated): June 25, 2026

Study Registration Dates

• First Submitted: March 17, 2025
• First Submitted That Met QC Criteria: April 1, 2025
• First Posted (Actual): April 3, 2025

Study Record Updates

• Last Update Posted (Estimated): July 1, 2025
• Last Update Submitted That Met QC Criteria: June 27, 2025
• Last Verified: June 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolism, Inborn Errors; Genetic Diseases, Inborn; Metabolic Diseases; Infections; Eye Diseases; Skin Diseases; Eye Diseases, Hereditary; Bacterial Infections and Mycoses; Pigmentation Disorders; Skin Diseases, Genetic; Amino Acid Metabolism, Inborn Errors; Albinism; Mycoses; Albinism, Oculocutaneous; Hypopigmentation
• Other Study ID Numbers: 24-PP-17

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No