Inclusion Criteria:
* Ankylosing spondylitis
* Age between 19 and 60 at the time of consent
* Diagnosis of ankylosing spondylitis based on the Modified New York criteria and the 2010 diagnosis of spondyloarthritis
* Willingness to participate voluntarily after comprehensively understanding the study and agreeing to adhere to the specified precautions
Family members of patients with ankylosing spondylitis
* Age between 19 and 65
* Must be a primary immediate family member (parent, brother, or sister) of the patient, who is related to the patient and has never been diagnosed with ankylosing spondylitis, and currently resides with the patient
* Willingness to participate voluntarily after attentively listening to the study's explanation, fully comprehending its details, and agreeing to adhere to the specified precautions
Exclusion Criteria for Ankylosing Spondylitis Patients:
1. Individuals who have taken antibiotics (oral/injected) within the last 3 months.
2. Individuals who have consumed lactic acid bacteria (health functional food) within the last 3 months.
Exclusion Criteria for Family Members of Ankylosing Spondylitis Patients:
Within a pre-planned period from the date of microbiome collection:
1. Individuals with a history of medication use listed in "drug use".
2. Individuals who have received a vaccine within the last 1 month (4 weeks) from the date of microbiome collection.
3. Individuals who have used topical antibiotics or topical steroids on the face, scalp, neck, arms, forearms, and hands within 24 hours of the date of microbiome collection.
4. Individuals who have used vaginal/vulvar medications, including antifungal drugs, within 24 hours from the date of microbiome collection.
5. Patients with acute illness (e.g., moderate or severe disease with or without fever, but sampling can be postponed until the subject recovers).
6. Patients with chronic and clinically significant medical conditions affecting the liver, digestive system, circulatory system, kidney, nervous system, respiratory system, endocrine system, immune system, blood system, malignant tumors, psychiatric history, or history of substance abuse.
7. Individuals who have made drastic changes to their diet for the purpose of rapid weight gain and loss within 4 weeks from the date of microbiome collection.
8. Individuals with gastrointestinal disorders that may affect microbiome analysis and are currently not medically controlled, or who are being treated for symptoms corresponding to the following diseases: Inflammatory bowel disease (e.g., Crohn's disease, ulcerative colitis), Irritable bowel syndrome (requiring medication), ulcers, acute or chronic pancreatitis, etc.
9. Individuals who need to use diapers for urinary incontinence.
10. Individuals who are suspected, based on medical opinion, to have conditions that may affect the collection of samples at the time of microbiome sample collection.
