A comparative study of qualitative tests for ketones in urine and serum.

111E DETECTION OF KETONE BODIES has become an important clinical measurement during the past 50 years. The two types of reactions most commonly employed for ketone detection are nitroprusside tests, which react with acetone and acetoacetic acid, and ferric chloride tests, which react with acetoacetic acid but not with acetone. Ferric chloride tests are very insensitive, give false-positive reactions with such common drugs as salicylate, and develop, with biologic compounds, other colors which mask the true acetoacetic acid reaction. Each modification of the nitroprusside test has its own sensitivity resulting from variations in concentration and variations in actual chemical compounds used. The nitroprusside test was standardized some time ago by the development of a simple tablet test called Acetest’ and has recently become available as a dip and read test called Ketostix.2 The present report describes these tests and presents results obtained with each on ketotic urine and serum samples and on normal samples with and without added acetoacetate.