This study aimed to assess the serum level of Leucine-rich alpha-2 glycoprotein 1 (LRG1) in Acne vulgaris (AV) individuals and evaluate the effect of probiotic therapy on these serum levels.

Acne vulgaris (AV) is a common inflammatory disorder of the pilosebaceous units, characterized by the presence of inflammatory, non-inflammatory, or a combination of both types of lesions.

Recent attention has turned toward biomarkers that reflect the inflammatory activity in acne and might act as indicators of disease severity, treatment response, or prognostic risk. One such candidate is Leucine-rich alpha-2 glycoprotein 1 (LRG1).

Probiotics are live microorganisms that, when administered in sufficient quantities, can modulate the composition of the gut microbiota, helping reduce microbial dysbiosis, regulate the immune response, and decrease inflammatory mediators, thereby reducing systemic inflammatory burden, which is called the gut-skin-axis relationship.

Inclusion Criteria:

• Age ≥18 years.
• Both sexes.
• Had not used systemic or topical acne therapy for at least two months or two weeks before the research, respectively.
• Participants with clinically diagnosed mild to moderate acne vulgaris (AV) based on the Global Acne Grading System (GAGS)

Exclusion Criteria:

• Pregnancy.
• Lactation.
• History of hypersensitivity to probiotic components.
• Smoking.
• Presence of infections.
• Autoimmune or malignant diseases.
• Receiving any systemic therapy likely to affect the microbiome or inflammatory biomarkers.

This case-control study was conducted on all participants enrolled from the Dermatology & Andrology Outpatient Clinic at Benha University Hospital, Egypt, between October 2024 and September 2025.

The data will be available upon a reasonable request from the corresponding author after the end of study for one year.

After the end of study for one year.

The data will be available upon a reasonable request from the corresponding author.