BUN (Blood Urea Nitrogen)

Urea is a metabolic end component produced by the liver during the catabolism process (urea cycle) which is filtered by the kidney and expelled in the urine. This test measures the blood urea nitrogen (BUN)) in the blood to examine the renal functions – KFT (kidney function test) and for diagnosis for kidney-related illnesses. It also helps in monitoring the outcome of the dialysis process and also in the efficacy of treatment (prognosis) modalities in acute and kidney diseases (restoring the physiological functions of kidneys by assessing the recovery of renal function).
Test Code: 446
₹ 100.00


Why Blood Urea Nitrogen Test?


Kidneys are vital organs performing various functions such as maintaining fluid and electrolyte balance, controlling blood pressure, eliminating metabolic end products, maintaining healthy bones, and maintaining normal RBC levels in the body. Various tests are performed to assess the health of the kidneys like blood urea, serum creatinine, blood urea nitrogen (BUN), glomerular filtration rate (GFR), creatinine clearance, urine proteins, urine micro-albumin, serum electrolytes, complete blood count, etc. Blood urea nitrogen levels provide insight into kidney functions and hence this test may be used for diagnosis, screening, or/and monitoring (prognosis). Sometimes BUN test is also interpreted along with creatinine to assess kidney function as BUN–to–Creatinine ratio (BUN: Creatinine). In pathological conditions the BUN–Creatinine ratio is altered. Thus BUN test is included as a part of the basic metabolic panel (BMP) or comprehensive metabolic panel (CMP). This screening test may also be prescribed during medical check-ups to screen as it provides insight into various multiple bodily symptoms as seen in some potential kidney conditions, liver diseases, diabetes, and cardiovascular-related disorders – congestive heart failure and in the prognosis of dialysis to monitor the current kidney function (to improve treatment modalities to prevent further damage of kidneys). BUN urea measures the amount of urea in the sample of blood. Urea is a metabolic end-product formed by the catabolism of proteins. This blood urea is also known as urea nitrogen is filtered out by kidneys from blood and thus eliminated from the body in the urine. Elevated levels of BUN levels can be due to usually common causes such as high protein diet, medications (amphotericin B, carbamazepine, cephalosporin, furosemide, methotrexate, methyldopa, rifampin, spironolactone, tetracycline, penicillin, steroids, vancomycin, sulfonamides, NSAIDS – ibuprofen, naproxen, proton pump inhibitors to treat gastric ulcers and/or GERD, etc), aging, high fat diet, high salt intake, sedentary life, over-hydration, stress, smoking, alcoholics and in pathologies like urinary tract obstruction, kidney stones, dehydration, shock, burn injuries, GI bleeding, etc. Low levels of BUN can be due to some normal physiological changes during pregnancy (second and third trimester of pregnancy which is reverted back to normal after childbirth), malnutrition –low protein diet, anemia, and in certain pathological conditions like diseases associated with liver and kidneys. Muscle cramps, numbness in the hands and legs, pain in the flank region, decreased urine output, burning sensation during urination, the appearance of urine may be red or brown, frequent urination especially at night, puffiness around face, wrist, and ankles, nausea and high blood pressure, etc could be reflected as clinical manifestations due to kidney-related diseases. Decreases in BUN levels associated with liver diseases may be exhibited as clinical manifestations like loss or gain in weight, weakness, nausea, vomiting, dark-colored urine, loss of appetite, swelling in the legs and ankles, etc. Higher levels of BUN are found in chronic kidney diseases with symptoms such as recurring fatigue, trouble sleeping, muscle cramps, itching, frequent urination and swelling in hands and legs, etc. 

General Instructions:

Sample Requirement: Specimen - Blood sample collected from the vein. Test Preparation: None.

NOTE - Sample for specimen collections may vary based on the patient’s condition/cases according to the patient’s presenting complaints/signs or symptoms:

SPECIMEN REQUIREMENT (Special or Rare Cases) - As instructed and guided by Physician / Clinician / Pathologist / as per Laboratory’s requirements, according to procedures and protocols.

Sample Requirement: A blood sample was taken from the vein

Test Preparation: None

This Multi-Specialty Clinical Referral Laboratory RT DIAGNOSTICS provides precise and accurate tests with an extensive range of testing services to the medical centers to help in the diagnosis and identification of pathology in the test specimens for infectious diseases and also to evaluate the function of organ systems of the patient. It prevents further complications and helps to stabilize and restore health to near normalcy at the earliest without delay.