yaya

• Urine investigations


  Screening for the presence of blood, protein, glucose, ketones, nitrates and leucocytes, and assessment of urinary pH and osmolality can be achieved by dipstick testing
• Urine color may vary


  Due to certain medications, foods, and medical conditions
• Red urine may indicate


  • Foods (beets, blackberries, rhubarb)
  • Drugs
  • Medical conditions: UTIS, renal stone, hemoglobinuria
• Orange urine may indicate

  • Foods (carrot, vitamin C)
  • Drugs (rifampin, phenazopyridine)
  • Dehydration
• Green urine may indicate


  • Food (asparagus)
  • Drugs (vitamin B, methylene blue, propofol, amitriptyline)
  • Medical condition: UTI
• Bilirubin should not be present in the urine
• Bilirubin


  Excreted in the urine in obstructive hepatobiliary conditions and in certain liver diseases, such as hepatitis
• Normal urinary proteins values are less than 150 mg/d and are undetectable using urinary dipstick
• The urinary dipstick only detects the presence of albumin and no other proteins
• When urinary protein values exceed 300-500mg/d


  The dipstick test result becomes positive
• The proteinuria on the dipstick


  Depends on the urine concentration, i.e. proteinuria increase with concentrated urine and vice versa
• The presence of leucocytes and nitrites in urine


  Is indicative of infection, inflammation, or contamination
• Urine pH


  Is useful for diagnosis of stones, infection, & acid-base imbalance
• Diet can also affect urinary pH levels


  Cranberries and high-protein diets create a more acidic PH, whereas citrus fruits and low-carbohydrate diets create a more alkaline PH
• Urine microscopy


  May detect dysmorphic erythrocytes, which suggest the presence of nephritis, or red cell casts, indicative of glomerular disease. White cell casts are strongly suggestive of pyelonephritis. Microscopy may also detect the presence of bacteria in cases of urinary infection, contamination, or if the urine left standing for too long in room temperature
• 24-hour urine collection period may be performed to measure excretion of solutes, such as calcium, oxalate and urate, and protein
• Ultrasonography(US)


  • Renal ultrasound is a valuable non-invasive technique that may be performed to assess renal size and texture and to investigate patients who have obstruction of the urinary tract, renal tumors, cysts or stones. Also it provide images of the prostate gland and bladder & reveal other abdominal, pelvic and retroperitoneal pathology
  • Doppler U/S imaging can be used to study blood flow in extrarenal and larger intrarenal vessels
  • Renal ultrasound is operator-dependent and the results are often less clear in obese patients
• Computed Tomography


  • Used to evaluate cysts and mass lesions in the kidney or filling defects within the collecting systems
  • It perform complete staging information and details of surrounding organs
  • Contrast enhancement is particularly useful for characterizing mass lesions within the kidney and differentiating benign from malignant lesions
  • Non-contrast CT of kidneys, ureters and bladder (CTKUB) is the method of choice for demonstrating stones within the kidney or ureter
  • Require contrast medium, which can cause renal dysfunction
  • The radiation dose is high
• Magnetic resonance imaging


  • Offers excellent resolution and gives good distinction between different tissue types
  • It is very useful for staging of prostate and bladder cancers
  • Magnetic resonance angiography (MRA) provides an alternative to CT for imaging renal vessels in cases of impaired renal function
  • No radiation
  • Involves administration of gadolinium-based contrast media, which may carry risks for patients with GFR<35
  • Expensive
  • Contraindicated in the presence of any metallic device (e.g. pacemaker, internal fixator, etc.)
• Urine dipstick


  • A standard urine test strip may comprise up to 10 different chemical reagents which react (change color) when immersed in, and then removed from, a urine sample. The test can be read 60 to 120 seconds after dipping
  • The analysis includes testing for the presence of protein, glucose, ketones, hemoglobin, bilirubin, urobilinogen, acetone, nitrite and leukocytes as well as testing of pH and specific gravity or to test for infection by different pathogens
  • The test strips consist of a ribbon made of plastic or paper of about 5-millimeter-wide, plastic strips have pads impregnated with chemicals that react with the compounds present in urine producing a characteristic color
  • The reading of the results is carried out by comparing the pad colors with a color scale provided by the manufacturer. Values are usually reported as: Trace, 1+, 2+, 3+ and 4+
• Advantages of urine dipstick


  • Decreased chance of human error
  • Rapid, cheap, and easy
• Disadvantages of urine dipstick


  • Not very accurate
  • False positive results is common, e.g. can occur with highly pigmented urine, ammonium compounds, chlorhexidine, and highly buffered alkaline urine
  • Can not differentiate the types of protein and is sensitive to albumin only