Blood

BLOOD

  • Haemoglobin contains a peroxidase which can liberate oxygen from hydrogen peroxide. This oxygen produces blue colour in the presence of benzidine.

Test (Click here for animation)

  • In a test tube, dissolve a small quantity of benzidine in glacial acetic acid
  • Add 2 ml of urine to this
  • Add one ml of fresh hydrogen peroxide and mix
  • Development of green to blue colour is positive for blood
    • Haematuria is the presence of whole blood in urine. Haemoglobinuria is the presence of haemoglobin in urine. Centrifuging the specimen of urine can differentiate this.
    • In haematuria, the red blood cells will settle as a layer at the bottom while the supernatant liquid is clear. In haemoglobinuria, the erythrocytes are ruptured and hence the fluid will be wine-red to brown.
Differentiate_Haematuria

Haematuria

    • Acute nephritis
    • Nephrosis – marked degeneration
    • Renal infarction
    • Passive congestion of kidneys
    • Neoplasms of kidney, bladder or prostate
    • Urolithiasis – renal, cystic or urethral
    • Abscess of kidney
    • Pyelonephritis
    • Ureteritis
    • Cystitis
    • Trauma to urethra – usually from improper catheterization
    • During estrus or postpartum in female due to contamination by uterine or vaginal discharge
    • Severe infection – anthrax, leptospirosis, infectious canine hepatitis
    • Chemical poisonings – Copper, Mercury, Sulfonamides and Phenol.
    • Thrombocytopaenia
    • Sweet clover poisoning
    • Parasites - Dioctophyma renale and Dirofilaria immitis in canines
    • Acute vegetative endocarditis and congestive heart failure in canine
  • If the blood is seen in the last drop of urine, then the source is bladder. If the urine is red throughout, the source of blood is kidney. If the first portion of urine is red, then the source of blood is some urethral lesions.

Haemoglobinuria

  • Parturient haemoglobinuria
  • Bacillary haemoglobinuria (Clostridium haemolyticum)
  • Leptospirosis
  • Piroplasmosis or Babesiosis
  • Haemolytic disease of the newborn
  • Photosensitization
  • Severe burns
  • Chemical haemolytic agents – sulfonamides, mercury and copper
  • Incompatible blood transfusion
  • Plant poisoning – Hellebose, Ranmunculus, Ash, Frosted turnips, Colchicum, convolvulus and other roots
  • Myoglobinuria
Last modified: Monday, 4 June 2012, 4:41 AM