HLA B27 Allele by PCR at Ayzal Lab

HLA B27 Allele by PCR at Ayzal Lab

The Human Leukocyte Antigen B27 (HLA-B27) Allele by Polymerase Chain Reaction (PCR) is a highly specialized molecular diagnostic test designed to detect the presence of the HLA-B27 gene variant on the surface of white blood cells. This specific allele is strongly associated with a group of chronic inflammatory autoimmune diseases known collectively as seronegative spondyloarthropathies. At Ayzal Lab in Lahore, Pakistan, this test is performed using advanced molecular diagnostic technology to ensure the highest level of clinical sensitivity and specificity. By utilizing PCR technology, the laboratory can directly amplify and identify the genetic material of the HLA-B27 allele, providing clinicians with definitive results that are crucial for early diagnosis, treatment planning, and patient management.

The HLA-B27 gene encodes a class I surface glycoprotein of the major histocompatibility complex (MHC). This protein plays a fundamental role in the immune system by presenting peptides to T-lymphocytes. However, the presence of this specific allele is linked to an increased susceptibility to autoimmune reactions, where the body’s immune system mistakenly attacks its own healthy tissues, particularly the joints of the spine, pelvis, and peripheral skeletal structures. The molecular detection of this allele is not a standalone diagnostic tool for any specific disease, but it serves as a critical diagnostic marker when evaluated alongside clinical symptoms, physical examinations, and radiological imaging. At Ayzal Lab, our molecular pathology department utilizes state-of-the-art thermal cyclers and real-time PCR assays to deliver highly accurate genetic profiling for patients presenting with symptoms of chronic joint inflammation.

Clinical Procedure: What to Expect

Patient Preparation

To ensure the integrity of the genetic sample and the accuracy of the PCR analysis, patients are advised to follow these preparation guidelines:

• No Fasting Required: There is no need to fast before this test. You may eat and drink normally prior to your appointment at Ayzal Lab.
• Medication Disclosure: Inform your physician and the laboratory staff about all medications you are currently taking, especially immunosuppressants, chemotherapy agents, or recent blood transfusions, as these can occasionally impact cellular yields.
• Hydration: Stay well-hydrated before the blood draw, as this makes the veins more accessible and the venipuncture process smoother.
• Identification and Documentation: Bring your physician’s referral slip and a valid government-issued identification card for verification purposes.

During the Procedure

The HLA B27 Allele by PCR test is a straightforward blood-based molecular investigation. The procedure involves the following steps:

• Patient Positioning: You will be asked to sit comfortably in a phlebotomy chair. The phlebotomist will locate a suitable vein, typically in the antecubital fossa (the crook of your elbow).
• Aseptic Preparation: The skin over the selected vein is thoroughly cleansed with an antiseptic solution (such as isopropyl alcohol) to prevent contamination of the sample.
• Venipuncture: A sterile, single-use needle is inserted into the vein to collect a whole blood sample. A mild pinching sensation may be felt during insertion.
• Sample Collection: The blood is drawn into an EDTA tube (purple top), which contains an anticoagulant necessary to preserve the white blood cells containing the genomic DNA.
• Post-Collection Care: Once the required volume of blood is collected, the needle is gently withdrawn, and a sterile cotton swab or bandage is applied to the puncture site. You will be asked to apply gentle pressure for a few minutes to stop any minor bleeding.
• Duration and Safety: The entire collection process takes less than 5 to 10 minutes. It is a highly safe, routine procedure with minimal risks, such as minor bruising or localized soreness at the needle insertion site.

When is an HLA B27 Allele by PCR Performed?

Ankylosing Spondylitis (AS)

Ankylosing Spondylitis is a chronic, progressive inflammatory arthritis that primarily affects the sacroiliac joints and the spine. Over time, it can lead to the fusion of the spinal vertebrae, causing severe stiffness, pain, and limited mobility. Physicians frequently request the HLA-B27 PCR test when a patient presents with chronic lower back pain that worsens with inactivity and improves with exercise. Because approximately 90% of patients with AS carry the HLA-B27 gene, a positive PCR result strongly supports the diagnosis when combined with characteristic radiographic findings of sacroiliitis.

Reactive Arthritis (Reiter’s Syndrome)

Reactive Arthritis is an inflammatory joint condition that develops in response to an infection in another part of the body, typically the gastrointestinal or genitourinary tract (caused by pathogens such as Chlamydia, Salmonella, or Campylobacter). Symptoms include joint pain, swelling, urethritis, and conjunctivitis. The HLA-B27 allele is present in 60% to 80% of these patients. Detecting this allele helps clinicians differentiate reactive arthritis from other forms of acute arthritis and predict a more severe or chronic disease course.

Psoriatic Arthritis

Psoriatic Arthritis is a form of inflammatory arthritis that affects some individuals who have psoriasis, a chronic skin condition characterized by red, scaly patches. When psoriatic arthritis primarily involves the spine (axial involvement), there is a strong association with the HLA-B27 allele. Testing for this marker helps rheumatologists classify the specific subtype of arthritis and tailor the therapeutic approach, which may include targeted biologic therapies.

Acute Anterior Uveitis

Acute Anterior Uveitis is the sudden inflammation of the middle layer of the eye (the uvea), specifically the iris and ciliary body. Patients experience eye pain, redness, photophobia (sensitivity to light), and blurred vision. Approximately 50% of patients with isolated acute anterior uveitis are HLA-B27 positive. Identifying this genetic marker is critical because uveitis associated with HLA-B27 is highly prone to recurrence and is frequently linked to underlying systemic inflammatory joint diseases.

Juvenile Idiopathic Arthritis (JIA)

Juvenile Idiopathic Arthritis refers to chronic joint inflammation in children under the age of 16. A specific subtype, enthesitis-related JIA, is closely linked to the HLA-B27 allele. Pediatric rheumatologists order this PCR test for children presenting with persistent joint pain, swelling, and inflammation at the sites where tendons or ligaments attach to bone (enthesitis). A positive result helps in early classification, risk stratification, and the initiation of aggressive therapy to prevent long-term joint damage.

What Does an HLA B27 Allele by PCR Detect?

The molecular analysis of the HLA-B27 allele at Ayzal Lab provides definitive genetic information. The test specifically detects:

• The presence or absence of the HLA-B27 gene sequence within the patient’s genomic DNA.
• Genetic predisposition to seronegative spondyloarthropathies.
• The specific molecular subtype of the HLA-B27 allele (when advanced typing is clinically indicated).
• Supportive evidence for the diagnosis of Ankylosing Spondylitis in symptomatic patients.
• Supportive evidence for the diagnosis of Reactive Arthritis following gastrointestinal or urogenital infections.
• Risk assessment for the development of systemic extra-articular manifestations, such as uveitis, aortitis, or pulmonary fibrosis.
• Differentiation between mechanical back pain and inflammatory back pain.
• Prognostic indicators for the severity and progression of inflammatory joint diseases.

Turnaround Time and Report Access at Ayzal Lab

At Ayzal Lab, we understand the anxiety and clinical urgency associated with diagnostic testing. The HLA B27 Allele by PCR is a complex molecular assay that requires precise DNA extraction, amplification, and detection phases. Typically, the verified test report is completed and authorized by our consultant molecular pathologist within 3 to 5 working days. Patients and referring physicians are notified via SMS once the report is ready. Reports can be easily accessed and downloaded online through the official Ayzal Lab patient portal, or collected in person from our main diagnostic center in Lahore.

HLA B27 Allele by PCR Findings Overview

Structure / Parameter Evaluated	Normal Findings	Possible Abnormal Findings
HLA-B27 Allele Status	Negative (Absent)	Positive (Present)
Genomic DNA Quality	Adequate for PCR amplification	Inadequate DNA yield (requires recollection)
Amplification Curve	No amplification detected	Sigmoid amplification curve indicating presence of allele
Clinical Correlation	Low probability of HLA-B27 associated autoimmune diseases	High susceptibility to Ankylosing Spondylitis, Reactive Arthritis, or Uveitis
Symptom Association	Symptoms likely due to mechanical or other non-HLA-B27 causes	Strong correlation with inflammatory back pain and joint stiffness

Note: Diagnostic findings should always be interpreted by a qualified healthcare professional together with the patient’s symptoms, medical history, physical examination, laboratory investigations, previous imaging studies, and other relevant clinical information. Additional investigations or specialist consultation may be recommended depending on the findings.

Why Choose Ayzal Lab for HLA B27 Allele by PCR?

• Experienced healthcare professionals: Our molecular pathology department is led by highly qualified pathologists and skilled laboratory technologists.
• Patient-focused care: We prioritize patient comfort, safety, and clear communication throughout the diagnostic process.
• Quality diagnostic services: Ayzal Lab adheres to strict internal and external quality control protocols to ensure reliable results.
• Professional reporting: Our reports are detailed, structured, and verified by consultant specialists for clinical accuracy.
• Modern diagnostic approach: We utilize advanced real-time PCR technology for high-sensitivity genetic testing.
• Comfortable environment: Our collection centers in Lahore are designed to provide a clean, hygienic, and welcoming environment.
• Convenient location: Easily accessible diagnostic facilities across Lahore make sample collection quick and hassle-free.
• Commitment to accurate diagnosis: We are dedicated to providing precise diagnostic insights that empower physicians to make informed treatment decisions.