Test for Bilirubin / Bile pigment in urine ( Fouchet's test for bilirubinuria )

Test for bilirubin / bile pigment in urine ( Fouchet's test )

Bilirubin is breakdown product of haemoglobin.
Normally no bilirubin passed in urine.

Apparatus

Test tube, 10% barium chloride, filter paper, dropper, fouchet's reagent, urine.

Principal

Oxidises bilirubin convert into green biliverdin with the help of ferric chloride.

Procedure

• Take 10ml of urine in a test tube.
• Add 3 -5 ml 10% barium chloride.
• Filter through filter paper.
• To precipitate on filter paper, add a few drops of fouchet's reagent. 

Fouchet's reagent = Ferric chloriode + Trichloroacetic acid

Result

Development of green colour indicates bilirubin.

Causes of bilirubinuria

1. Obstructive jaundice
2. Hepatocellular jaundice. 

Test for bile salts ( Hay's test )

Test for bile salts ( Hay's test )

Apparatus

Test tube (capacity 50 or 100ml), Sulphur powder, urine.

Principle

If bile salts present in urine lower the surface tension of the urine.

Procedure

• Test tube fill  2/3 with urine.
• Sprinkle finely sulphur powder over it.

Hay's test

Results

If bile salts present in urine then sulphur powder sinks, otherwise floats.

Cause for bile salts in urine

• Obstructive jaundice

Test for ketonuria ( Rothera's test )

Test for ketonuria ( Rothera's test )

Apparatus

Test tube, Urine, Solid ammonium sulfate salt, Sodium nitroprusside, liquor ammonia.

Principle

Ketone bodies combine with alkaline solution of sodium nitroprusside formed purple complex.

Procedure

• Take 5ml urine in a test tube.
• Saturate it with solid ammonium salt, it will start settling to the bottom of the tube when it saturated.
• Add a few crystals of sodium nitroprusside and shake.
• Add liquor ammonia in test tube with the side of the inner wall.

Rothera's test

Results

Appearance of the purple coloured ring at the junction indicates presence of ketone bodies.

Causes of ketonuria

• Diabetes ketoacidosis
• Dehydration
• Hyperemesis gravidarum
• Fever
• Cachexia
• After general anaesthesia

Test for glucosuria ( Benedict's reagent test )

Test for glucosuria ( Benedict's reagent test )

Glucosuria is define is the excretion of sugar in urine.

Apparatus

Benedict's reagent, Test tube, Urine, Lighter, Candle,

Principle

Cupric ion reduced by glucose to cuprous oxide and a coloured precipitate is formed.

Procedure

• In test tube take 5ml of benedict's reagent.
• Add 8 drops or 0.5 ml urine.
• Heat to boiling for two minutes.
• Cool in water bath or running tap water.
• Than look for colour change and precipitation.

Benedict's test

Results

Normally 130 mg / day glucose comes out with urine.

• Blue colour (no change colour ) = Negative
• Greenish colour                          = Traces ( less than 0.5 g /day ).
• Green / cloudy green ppt            = + ( 0.5 - 1 g/dl ).
• Yellow ppt                                  = ++ ( 1-1.5 g / dl ).
• Orange ppt                                  = +++ ( 1.5 - 2 g / 100ml ).
• Brick ppt                                     = ++++ ( more than 2 g / dl ).

Semiquantitative interpretation

Causes

• Diabetes mellitus
• Renal glucosuria
• Severe burns
• Administration of corticosteroids
• Severe sepsis
• Pregnancy

Test for proteinuria ( Heat and acetic acid test )

Test for proteinuria (Test for protein in urine ) / Heat and acetic acid test

Apparatus 

Test tube, Acetic acid, Candle, Lighter, Test tube holder, Dropper, Urine.

Principle

Heat causes coagulation of protein.

Procedure

• Take 5ml test tube.
• Fill 2/3 with urine.
• Now acidify urine by the adding a few drops of 3% acetic acid, if urine is alkaline.
• Boil upper portion for two minutes ( boil upper portion because it can compare with the lower portion ).
• If turbidity appears, add a few drops of 3% acetic acid

Test for proteinuria

Results

If present...

• No cloudiness                             = Negative
• Faint cloudiness                          = Traces ( less than 0.1 g/dl ).
• Cloudiness without granularity   = + ( 0.1 g /100ml ).
• Granular cloudiness                     = ++ ( 0.1 - 0.2 g / 100ml ).
• Precipitation and flocculation      = +++ ( 0.2 -0.4 g/100ml ).
• Thick solid precipitation              = ++++ ( more than 0.5 g/100ml ).

Causes

Normally less than 150 mg/day protein comes with/in urine.

Mild proteinuria ( less than 1.0 gm/day ) occur in...

• Hypertension
• Polycystic kidney
• Chronic pyelonephritis
• UTI
• Fever

Moderate proteinuria ( 1-3 gm/day ) is seen in...

• Chronic glomerulonephritis
• Nephrosclerosis
• Multiple myeloma
• Pyelonephritis

Heavy proteinuria ( more than 3gm/day ) occur due to...

• Nephrotic syndrome
• Renal vein thrombosis
• Diabetes mellitus
• SLE