HLAB27

Immunity

Report in 12Hrs

At Home

No Fasting Required

Details

HLA-B27 is not a disease but is strongly associated with autoimmune disorders, especially seronegative spondyloarthropathies.

₹799₹1,100

27% OFF

HLA B27 Test Information Guide

Why is it done?
- Detects Human Leukocyte Antigen B27 (HLA-B27), a genetic marker present on white blood cells that plays a role in immune system function and is strongly associated with certain autoimmune and inflammatory diseases
- Aids in diagnosis of seronegative spondyloarthropathies including ankylosing spondylitis, reactive arthritis, psoriatic arthritis, and enteropathic arthritis
- Ordered when patients present with symptoms of chronic inflammation, back pain, joint pain, uveitis, or inflammatory bowel disease with arthritic manifestations
- Used for family screening when a relative has been diagnosed with an HLA-B27 associated condition
- Performed when evaluating patients with unexplained inflammatory arthritis, chronic back pain unresponsive to typical treatment, or recurrent uveitis
Normal Range
- Normal Result: Negative or Absent - indicates HLA-B27 antigen is not present on blood cells
- Abnormal Result: Positive or Present - indicates HLA-B27 antigen is detected; reported as percentage or presence/absence
- Typical Reference Range: Approximately 6-8% of the general Caucasian population carries HLA-B27; prevalence varies by ethnicity (lower in African Americans, higher in certain Scandinavian populations)
- Units of Measurement: Reported as Negative/Positive or Present/Absent; may be expressed as percentage of cells expressing the antigen
- Interpretation: Negative result suggests lower risk for HLA-B27 associated diseases; positive result increases suspicion but does not confirm diagnosis, as not all HLA-B27 positive individuals develop disease
Interpretation
- Positive HLA-B27 Result: Significantly increases risk for developing spondyloarthropathies; approximately 90% of ankylosing spondylitis patients are HLA-B27 positive; however, only 1-3% of HLA-B27 positive individuals develop clinically significant disease
- Negative HLA-B27 Result: Makes ankylosing spondylitis and reactive arthritis less likely but does not exclude diagnosis; approximately 10% of ankylosing spondylitis patients are HLA-B27 negative; other inflammatory conditions may still be present
- Clinical Context Importance: Results must be interpreted alongside clinical presentation, imaging findings, laboratory markers (elevated CRP, ESR), and physical examination findings
- Factors Affecting Results: Ethnic background (prevalence varies by population), age at testing, presence of active infection (may temporarily affect lymphocyte populations), recent immunosuppressive therapy, and technical factors in flow cytometry testing
- Clinical Significance of Different Patterns: Positive result with back pain, inflammatory markers, and morning stiffness strongly suggests ankylosing spondylitis; positive result with asymmetric peripheral arthritis suggests reactive arthritis; positive result with skin lesions and arthritis suggests psoriatic arthritis
- Prognostic Value: Positive HLA-B27 in patients with inflammatory arthritis predicts more aggressive disease course and greater likelihood of extra-articular manifestations
Associated Organs
- Primary Organ Systems Involved: Musculoskeletal system (joints and spine), immune system, eyes (uveal tissue), gastrointestinal tract, skin, and cardiovascular system
- Ankylosing Spondylitis: Progressive inflammatory condition affecting the spine and sacroiliac joints; 90% of patients are HLA-B27 positive; leads to vertebral fusion and reduced spinal mobility; affects approximately 0.1-1% of the population
- Reactive Arthritis: Sterile joint inflammation occurring after infection (gastrointestinal or genitourinary); 60-80% of patients with reactive arthritis carry HLA-B27; characterized by asymmetric lower extremity arthritis
- Psoriatic Arthritis: Inflammatory arthritis associated with psoriasis; 50-70% of psoriatic arthritis patients are HLA-B27 positive when spondylitis or axial involvement present; affects skin, joints, and connective tissues
- Enteropathic Arthritis: Joint inflammation associated with inflammatory bowel disease (Crohn's disease or ulcerative colitis); 50-75% of patients with enteropathic arthritis are HLA-B27 positive
- Acute Anterior Uveitis: Inflammation of the uvea (middle layer of the eye); 50% of acute uveitis cases are associated with HLA-B27; can lead to vision loss if untreated; often recurrent
- Extra-Articular Manifestations: Fatigue, fever, night sweats, weight loss, skin manifestations (keratoderma, nail dystrophy), mucosal ulceration, and systemic inflammation
- Potential Complications: Spinal fusion with loss of mobility, chronic pain, disability, vision impairment or blindness from recurrent uveitis, cardiac arrhythmias from myocarditis, pulmonary fibrosis, and psychological impacts from chronic disease burden
Follow-up Tests
- Initial Confirmation and Disease Assessment: Erythrocyte Sedimentation Rate (ESR), C-Reactive Protein (CRP), and Complete Blood Count (CBC) to assess inflammation levels
- Imaging Studies: Pelvic and lumbar spine X-rays or MRI to evaluate for sacroiliitis and vertebral changes; ultrasound of affected joints to assess inflammation and structural damage
- Rheumatologic Panel: Rheumatoid Factor, Anti-CCP antibodies, and Antinuclear Antibody (ANA) to rule out other autoimmune conditions
- Ophthalmologic Evaluation: Referral to ophthalmology for comprehensive eye examination, slit-lamp examination, and baseline visual acuity assessment in HLA-B27 positive patients
- Gastrointestinal Investigation: Colonoscopy or esophagogastroduodenoscopy if inflammatory bowel disease suspected; fecal calprotectin levels to assess gut inflammation
- Infection Screening: Testing for triggering infections (Chlamydia, Salmonella, Shigella, Yersinia) if reactive arthritis suspected; sexual history and urethritis evaluation
- Cardiovascular Assessment: Echocardiography and EKG if cardiac involvement suspected; assess for aortitis, aortic regurgitation, or conduction abnormalities
- Pulmonary Assessment: Chest X-ray and pulmonary function tests in long-standing disease to assess for pulmonary fibrosis
- Monitoring Frequency: ESR and CRP every 3-6 months during active disease; annual imaging for established ankylosing spondylitis; ophthalmology follow-up as needed (3-6 months intervals with uveitis); clinical assessment at each rheumatology visit
- Family Screening: HLA-B27 testing for first-degree relatives of affected individuals; genetic counseling recommended for high-risk families
Fasting Required?
- Fasting Requirement: NO - Fasting is not required for HLA-B27 testing
- Sample Collection: Simple blood test performed via venipuncture; blood sample is collected in EDTA (lavender top) tube for flow cytometry testing
- Specimen Handling: Sample should be sent to laboratory promptly; viable white blood cells required for accurate testing; keep at room temperature during transport
- Medications to Avoid: No specific medications need to be discontinued; however, immunosuppressive therapy may potentially affect lymphocyte counts; inform phlebotomist of current medications
- Pre-Test Preparation: No special preparation required; patient may eat and drink normally; adequate hydration may help with blood draw; arrive on time at collection site
- Timing Considerations: Test can be performed at any time of day; no temporal relationship to meals or activities; recent infection or active inflammation does not affect HLA-B27 expression
- Patient Instructions: Wear loose, comfortable clothing for easy blood draw access; inform phlebotomist of previous venipuncture difficulties; remain seated or lie down if prone to fainting

How our test process works!