Basic Concepts in Clinical Biochemistry-A Practical Guide.7z

Qualitative Analysis of Ketone Bodies

in Urine^30

30.1 Theory

The three compounds, namely, acetone, acetoacetic acid, andβ-hydroxybutyrate, are
called ketone bodies. Ketone bodies are water-soluble and energy-yielding
substances. The synthesis of ketone bodies is called ketogenesis. The ketogenesis
process occurs in the liver particularly during periods of low food intake,
carbohydrate-restrictive diets, starvation, or in untreated type 1 diabetes mellitus.
Ketone bodies are transported from the liver to the extrahepatic tissues and converted
intoacetyl-CoAwhich then enters thecitric acid cycleand is utilized for energy
production (Fig.30.1). The liver, however, is unable to metabolize ketone bodies.
The tissues which lack mitochondria, i.e., erythrocytes, also cannot utilize ketone
bodies. Ketone bodies are major fuel source for the brain during starvation and can
meet 50–70% of total energy needs. The relative proportion of ketone bodies present
in blood may vary from 78% (β-hydroxybutyric acid) to 20% (acetoacetic acid) and
2% (acetone). Tests for ketone bodies should be done on fresh urine sample.

CH 3 CH 3 CH 3

O

C

O

O

O O

O

C

H

OH

CH 2 C CH 3 CCCH 2

Acetone Acetoacetate D-b-Hydroxybutyrate

Ketone bodies

#Springer Nature Singapore Pte Ltd. 2018
V. Kumar, K. D. Gill,Basic Concepts in Clinical Biochemistry: A Practical Guide,
https://doi.org/10.1007/978-981-10-8186-6_30

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