Test for blood in urine

TEST FOR BLOOD IN URINE

Benzidine Test

  • Psuedo peroxidase reaction for detection of blood in urine.
  • To 2 ml of urine, add 1-2 drops of benzidine reagent and 4 ml of 3% H2O2.
  • Appearance of blue colour  indicates the presence of blood in urine.

Clinical significance

  • Hematuria (RBC in urine) occur in conditions like pyelonephritis, cystitis,   urolithiasis, neoplasms of kidney, presence of parasites such as Dictophyma renale and also in heavy metal poisonings.
  •  Hemoglobinuria (Hb in urine) is a common symptom in leptospirosis, piroplasmosis etc. Sometimes, they are caused by chemical hemolytic agents like Cu, Hg etc. and bacteria like clostridium hemolyticum.

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: Thursday, 1 December 2011, 7:09 AM