HLA typing B51 locus Molecular typing, EDTA Blood

Immunity

Report in 48Hrs

At Home

No Fasting Required

Details

Genetic HLA matching.

₹9,842₹14,060

30% OFF

HLA Typing B51 Locus Molecular Typing - EDTA Blood

Why is it done?
- Test Purpose: Molecular identification of Human Leukocyte Antigen (HLA) B51 allele using DNA-based typing methods from blood samples collected in EDTA anticoagulant tubes
- Organ Transplantation: HLA typing is essential for donor-recipient matching in kidney, heart, liver, pancreas, and bone marrow transplantation to minimize rejection risk
- Disease Association: HLA-B51 is strongly associated with Behçet's disease, particularly in Mediterranean, Middle Eastern, and Asian populations
- Autoimmune Condition Screening: Identifies patients at risk for HLA-associated autoimmune and inflammatory conditions
- Immunological Research: Used in genetic studies, population screening, and immunological research protocols
- Timing: Performed before transplant procedures, during diagnostic evaluation for suspected Behçet's disease or related conditions, or as part of routine immunological assessment
Normal Range
- Result Format: Results are reported as the presence or absence of HLA-B51 allele; reported as either positive (HLA-B51 present) or negative (HLA-B51 absent)
- Reference Range: No standard "normal" or "abnormal" values exist. Results indicate presence or absence of the HLA-B51 allele with zygosity status (homozygous or heterozygous if present)
- Units: Qualitative (Presence/Absence) - genotype nomenclature (e.g., HLA-B*51:01)
- Normal (Negative) Result: HLA-B51 allele not detected; patient has two other HLA-B alleles; population prevalence is approximately 2-12% depending on ethnic background
- Abnormal (Positive) Result: HLA-B51 allele detected (heterozygous or homozygous); indicates genetic predisposition to HLA-B51-associated conditions; requires clinical correlation
- Interpretation Principle: HLA-B51 presence is necessary but not sufficient for disease development; clinical manifestations depend on additional genetic and environmental factors
Interpretation
- HLA-B51 Negative (Not Detected): Patient does not carry HLA-B51 allele; lower genetic risk for Behçet's disease and HLA-B51-associated conditions; may have different HLA-B alleles that may be associated with other autoimmune conditions
- HLA-B51 Positive, Heterozygous: Patient carries one copy of HLA-B51 allele; carries one other HLA-B allele; increased genetic susceptibility to Behçet's disease (odds ratio 10-50 in affected populations); approximately 40% of Behçet's patients are HLA-B51 positive
- HLA-B51 Positive, Homozygous: Patient carries two copies of HLA-B51 allele; carries both HLA-B chromosomes with B51; significantly increased genetic risk for Behçet's disease and related conditions; rare in general population (typically <1%)
- Transplantation Context: HLA-B51 presence in recipient and/or donor is matched to determine HLA compatibility score; more closely matched donor-recipient pairs have lower rejection rates and improved long-term outcomes
- Factors Affecting Results: Genetic inheritance patterns (Mendelian); ethnic/ancestral background (higher prevalence in Mediterranean, Middle Eastern, East Asian populations); laboratory methodology accuracy; sample quality and DNA extraction efficiency
- Clinical Significance for Behçet's Disease: HLA-B51 positivity increases pre-test probability in patients with clinical symptoms; associated with earlier disease onset (before age 40) and higher risk for ocular and vascular involvement; negative result makes diagnosis less likely but does not exclude Behçet's disease
- Asymptomatic Carriers: Many HLA-B51-positive individuals remain asymptomatic; presence of allele alone does not predict disease development; gene-environment interactions play important roles
Associated Organs
- Immune System: Primary system involved; HLA molecules present antigens to T-lymphocytes; HLA-B51 restricted CD8+ T-cell responses implicated in disease pathogenesis
- Eyes (Ocular Manifestations): Anterior uveitis, posterior uveitis, retinal vasculitis; HLA-B51 associated with severe ocular disease and vision loss; most common cause of morbidity in Behçet's disease
- Mouth and Genitals: Recurrent oral and genital ulcers; hallmark of Behçet's disease; immune-mediated inflammation of mucosal surfaces
- Skin: Erythema nodosum, papulopustular lesions, acneiform eruptions; cutaneous vasculitis manifestations
- Vascular System: Vasculitis affecting veins and arteries; thrombosis (venous more common than arterial); HLA-B51 predicts more severe vascular involvement
- Central Nervous System: Neuro-Behçet's disease with meningoencephalitis, brainstem involvement, spinal cord disease; myelopathy and stroke-like events
- Gastrointestinal Tract: Ulceration from mouth to anus; inflammation throughout GI tract; risk of perforation and bleeding
- Potential Complications from Abnormal Results: Blindness from recurrent uveitis; cardiovascular events from vasculitis; neurological disability; organ transplant rejection if not properly matched; bowel perforation; thrombotic events
- Associated Diseases: Primary: Behçet's disease; Secondary: Other HLA-B51-associated conditions including some cases of reactive arthritis and certain vasculitides
Follow-up Tests
- If HLA-B51 Positive with Suspected Behçet's Disease: Comprehensive ophthalmologic examination (slit lamp, fundoscopy); inflammatory markers (ESR, CRP); HLA-A, HLA-B, HLA-C, HLA-DR, HLA-DQ complete typing; Pathergy test; Rheumatologic assessment
- Transplantation Context: Complete HLA typing of all loci (A, B, C, DR, DQ, DP); Donor-specific antibody (DSA) screening; Panel-reactive antibody (PRA) assessment; Crossmatching studies; Kidney or organ-specific function tests
- Immunological Workup: Autoantibodies (ANA, anti-dsDNA, ANCA); Complete blood count with differential; Thyroid function tests; Liver and renal function tests
- Imaging Studies: MRI brain and spinal cord (if neuro-Behçet's suspected); Optical coherence tomography (OCT) for ocular involvement; Duplex ultrasound or angiography for vascular involvement; CT chest/abdomen for systemic disease
- Additional HLA Testing: High-resolution HLA-B locus typing to identify specific B51 allele subtypes (B*51:01, B*51:02, etc.); Other HLA-associated disease screening if indicated
- If HLA-B51 Negative with Clinical Symptoms: Alternative HLA associations tested; Complete HLA panel analysis; Rule out other autoimmune/inflammatory conditions; Repeat testing may be considered with different methodology
- Monitoring Frequency: HLA typing is performed once per patient (stable genetic marker); Does not require repeat testing unless new transplant or diagnosis considerations arise; Clinical disease activity monitored separately with periodic physician assessment
- Family Counseling: Genetic counseling for HLA-B51-positive patients; Family member screening may be considered if hereditary disease pattern; Inheritance pattern counseling (autosomal co-dominant)
Fasting Required?
- Fasting Requirement: No
- Patient Preparation: No fasting required; patient may eat and drink normally before blood draw; no special dietary restrictions
- Specimen Collection Requirements: Venipuncture blood collection into EDTA (ethylenediaminetetraacetic acid) anticoagulant tube (lavender-topped tube); EDTA preserves DNA integrity for molecular typing; Minimum 2-3 mL typically required
- Medications - No Special Restrictions: All routine medications may be continued as scheduled; HLA typing is not affected by medications; Take all regular medications normally on test day
- Sample Stability and Storage: EDTA blood sample stable at room temperature for 24-48 hours; Refrigeration at 2-8°C extends stability to 7 days; Protect from direct sunlight and extreme temperatures; Avoid hemolysis or clotting
- Timing Considerations: Can be performed at any time of day; no circadian variations affect results; Recent illness or infection does not affect HLA genotyping results
- Special Instructions: Notify laboratory of any recent blood transfusion (may affect results); Inform of pregnancy status if female; Report any recent medications or immunosuppressive therapy; Ensure proper tube labeling and patient identification

How our test process works!