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