Quantitative Faecal Immunochemical Test at Chughtai Lab

Quantitative Faecal Immunochemical Test (QFIT) at Chughtai Lab

The Quantitative Faecal Immunochemical Test (QFIT) is an advanced, highly sensitive diagnostic laboratory investigation designed to detect trace amounts of hidden (occult) human blood in stool samples. Unlike traditional chemical-based fecal occult blood tests (gFOBT), the QFIT utilizes specific antibodies that bind exclusively to human hemoglobin. This immunochemical methodology ensures that the test is highly specific to lower gastrointestinal bleeding, as hemoglobin originating from the upper digestive tract is typically degraded by gastric and intestinal enzymes before reaching the colon. By measuring the exact concentration of human hemoglobin in feces, the QFIT serves as a pivotal, non-invasive screening tool for colorectal cancer, premalignant adenomatous polyps, and various other inflammatory or structural disorders of the lower gastrointestinal tract.

To provide patients in Pakistan with access to world-class diagnostic standards, Chughtai Lab partners with The Doctors Laboratory (TDL) in the United Kingdom to perform this specialized analysis. TDL is one of Europe's leading clinical laboratories, renowned for its stringent quality control protocols, advanced molecular and immunochemical technologies, and international accreditations. When a patient submits a sample for the QFIT at Chughtai Lab, the specimen is carefully processed, stabilized, and transported under strict cold-chain logistics to TDL UK. This collaborative diagnostic pathway ensures that patients receive exceptionally accurate, quantitative results that clinical teams can confidently rely upon for critical decision-making regarding colonoscopies and further gastrointestinal interventions.

The primary clinical value of the QFIT lies in its ability to identify microscopic bleeding that is invisible to the naked eye. Early-stage colorectal malignancies and large adenomatous polyps often bleed intermittently and in minute quantities. Detecting this occult blood allows gastroenterologists and oncologists to intervene at a stage when colorectal cancer may be entirely asymptomatic and highly curable. Furthermore, because the test is quantitative, it provides a numerical value (measured in micrograms of hemoglobin per gram of feces, or µg/g) rather than a simple positive or negative result. This quantitative data helps clinicians stratify risk, determine the urgency of diagnostic colonoscopies, and monitor patients with known gastrointestinal pathologies over time.

Clinical Procedure: What to Expect

Patient Preparation

Proper patient preparation is essential to ensure the integrity of the stool specimen and the accuracy of the quantitative analysis. Because the QFIT utilizes immunochemical technology specific to human hemoglobin, patients do not need to follow restrictive dietary protocols prior to sample collection. However, specific clinical guidelines must be followed to avoid false-positive or false-negative results:

• No Dietary Restrictions: Unlike older guaiac-based tests, you do not need to avoid red meat, vitamin C, or specific fruits and vegetables before taking this test.
• Avoid Testing During Active Bleeding: Do not collect a stool sample if you have active bleeding from hemorrhoids (piles), anal fissures, or if you are currently menstruating. Wait at least three days after these bleeding episodes have completely resolved before collecting the sample.
• Medication Review: Inform your prescribing physician of all medications you are currently taking. While routine medications do not usually interfere with the QFIT, certain blood thinners, nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen or aspirin, and oral iron supplements can occasionally influence gastrointestinal bleeding patterns. Do not discontinue prescribed medications without consulting your doctor.
• Avoid Contamination: Ensure the stool sample does not come into contact with toilet water, urine, soap, or household cleaning chemicals, as these substances can degrade the hemoglobin proteins and invalidate the test results.
• Use the Provided Collection Kit: Only use the specialized collection device and transport container provided by Chughtai Lab. This kit contains a specific preservative buffer designed to stabilize human hemoglobin during transit to TDL UK.

During the Procedure

The collection of a stool sample for the Quantitative Faecal Immunochemical Test is entirely non-invasive, painless, and completed in the privacy of your home. The process involves the following clinical steps:

• Preparation: Wash your hands thoroughly and open the sterile collection kit. Write your full name, date of birth, and the exact date and time of collection on the tube label.
• Stool Collection: Pass stool into a clean, dry container, or onto a clean sheet of paper or plastic wrap suspended over the toilet bowl. Do not allow the stool to fall into the toilet water.
• Sampling: Unscrew the cap of the QFIT collection tube. Attached to the cap is a small sampling probe. Scrape the tip of the probe across the surface of the stool sample in several different areas. Only a very small amount of stool is required to fill the grooves on the probe.
• Securing the Sample: Insert the probe back into the collection tube and click the cap shut tightly. Do not reopen the tube after it has been sealed. Shake the tube gently to mix the sample with the liquid preservative buffer.
• Storage and Delivery: Place the sealed tube into the biohazard bag provided. Store the sample at room temperature or in a refrigerator (do not freeze) as instructed by Chughtai Lab staff, and return it to your nearest Chughtai Lab collection center as soon as possible, ideally within 24 hours of collection, to initiate the international transport protocol to TDL UK.

When is a Quantitative Faecal Immunochemical Test (QFIT) Performed?

Colorectal Cancer Screening

Physicians routinely request the QFIT as a primary screening tool for colorectal cancer in asymptomatic individuals, typically starting at age 45 or 50, or earlier for patients with a significant family history of gastrointestinal malignancies. Because early-stage colorectal tumors often shed microscopic amounts of blood into the stool long before physical symptoms develop, the QFIT assists in identifying high-risk individuals who require definitive diagnostic evaluation via colonoscopy.

Unexplained Iron Deficiency Anemia

When a patient presents with iron deficiency anemia without an obvious cause, clinicians must investigate potential sources of chronic, low-grade blood loss within the gastrointestinal tract. The QFIT is highly effective in detecting occult lower GI bleeding, helping physicians differentiate between nutritional deficiencies and organic pathologies such as occult malignancies, angiodysplasia, or inflammatory bowel disease.

Persistent Change in Bowel Habits

A sudden or gradual alteration in bowel habits, such as persistent diarrhea, unexplained constipation, or alternating patterns lasting for several weeks, warrants clinical investigation. Gastroenterologists utilize the QFIT to determine if these functional changes are accompanied by mucosal damage and occult bleeding, which helps guide the diagnostic pathway toward either functional bowel disorders or structural diseases.

Unexplained Weight Loss and Abdominal Pain

The combination of involuntary weight loss and chronic abdominal discomfort is a clinical red flag that requires comprehensive diagnostic evaluation. A QFIT is performed to screen for underlying inflammatory, infectious, or neoplastic processes in the large intestine that may be causing localized tissue damage, malabsorption, and chronic micro-bleeding.

Surveillance of High-Risk Individuals

For patients with a personal history of adenomatous polyps, inflammatory bowel disease, or a family history of hereditary colorectal cancer syndromes (such as Lynch syndrome), the QFIT may be utilized as an adjunct surveillance tool. While colonoscopy remains the gold standard for high-risk surveillance, the QFIT provides a valuable, non-invasive interval assessment to detect early signs of recurrent neoplastic activity.

What Does a Quantitative Faecal Immunochemical Test (QFIT) Detect?

The Quantitative Faecal Immunochemical Test is designed to detect and quantify human hemoglobin in stool, which serves as a clinical marker for several lower gastrointestinal conditions. A positive or elevated QFIT result can indicate the presence of:

• Colorectal adenocarcinoma (primary colon or rectal cancer)
• Advanced adenomatous polyps (premalignant growths in the colon)
• Benign colorectal polyps
• Ulcerative Colitis (active mucosal inflammation and ulceration)
• Crohn's Disease (transmural inflammation affecting the colon)
• Diverticular disease (diverticulosis or acute diverticulitis)
• Internal or external hemorrhoids with active micro-bleeding
• Anal fissures (small tears in the lining of the anus)
• Gastrointestinal angiodysplasia (malformed, fragile blood vessels)
• Infectious colitis (bacterial, viral, or parasitic infections causing mucosal damage)
• Ischemic colitis (compromised blood flow to the large intestine)
• Radiation proctitis (inflammation following pelvic radiation therapy)
• NSAID-induced colonic ulcers
• Solitary rectal ulcer syndrome
• Large bowel fistulas
• Intussusception or volvulus causing mucosal congestion and bleeding
• Colorectal endometriosis (rare mucosal bleeding during menstruation)
• Pseudomembranous colitis (Clostridioides difficile infection)
• Stercoral ulcers (ulceration caused by severe, impacted stool)
• Eosinophilic colitis

Turnaround Time and Report Access at Chughtai Lab

Because the Quantitative Faecal Immunochemical Test (QFIT) is an outsourced investigation performed at The Doctors Laboratory (TDL) in the United Kingdom, the turnaround time reflects the necessity of international transport, customs clearance, and specialized laboratory processing. Typically, results are available within 7 to 10 working days from the date of sample submission at Chughtai Lab. Chughtai Lab employs a state-of-the-art cold-chain logistics system to ensure that all outsourced specimens remain stabilized and preserved at optimal temperatures throughout their journey to London, maintaining the absolute integrity of the sample.

Once the analysis is completed by the consultant pathologists at TDL UK, the verified quantitative report is securely transmitted back to Chughtai Lab's integrated laboratory information system. Patients and their referring physicians are immediately notified via SMS when the report is ready. Reports can be accessed and downloaded digitally through the official Chughtai Lab website or the Chughtai Lab mobile application. Physical copies of the reports can also be collected from any Chughtai Lab diagnostic center or delivered directly to the patient's home through their dedicated dispatch service.

Quantitative Faecal Immunochemical Test (QFIT) Findings Overview

Structure / Parameter Evaluated	Normal Findings	Possible Abnormal Findings
Fecal Hemoglobin Concentration	< 10 µg/g (micrograms of hemoglobin per gram of feces)	≥ 10 µg/g (indicates significant lower GI bleeding)
Colorectal Mucosa	Intact, healthy mucosa with no active micro-bleeding	Ulcerated, inflamed, or friable mucosa shedding blood
Neoplastic Lesions	Absence of bleeding adenomas, carcinomas, or polyps	Bleeding colorectal adenocarcinoma or advanced adenomatous polyps
Vascular Integrity	Normal vascular structure without fragile or ruptured vessels	Bleeding angiodysplasia, varices, or hemorrhoidal complexes
Inflammatory Status	No active immunochemical signs of mucosal inflammation	Elevated hemoglobin secondary to active IBD or infectious colitis
Structural Anomalies	No bleeding associated with diverticula or structural defects	Bleeding diverticular pouches, fissures, or fistulas
Therapeutic Response	Undetectable fecal hemoglobin following successful treatment	Persistent elevated fecal hemoglobin indicating ongoing pathology

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 Chughtai Lab for Quantitative Faecal Immunochemical Test (QFIT)?

• International Collaboration: Chughtai Lab partners with The Doctors Laboratory (TDL) in the UK, ensuring your sample is analyzed using world-class European diagnostic standards.
• Advanced Cold-Chain Logistics: Specialized transport protocols guarantee that your stool specimen remains stabilized and preserved from Pakistan to the UK.
• Experienced Healthcare Professionals: A dedicated team of pathologists and laboratory technicians oversees the collection, pre-analytical preparation, and reporting processes.
• Convenient Sample Collection: With a vast network of collection centers across Pakistan, patients can easily obtain collection kits and drop off samples.
• Digital Report Access: Secure, rapid access to your quantitative reports via the Chughtai Lab mobile app and online portal.
• Quality Diagnostic Services: Strict adherence to international quality control guidelines and laboratory safety standards.
• Patient-Focused Care: Compassionate staff members are available to guide you through the correct sample collection procedures to prevent errors.
• Comprehensive Diagnostic Menu: Chughtai Lab offers seamless integration of follow-up diagnostic services, including radiology, pathology, and specialist consultations.