Randox has introduced the Ranbut assay, which offers high linearity and excellent sensitivity for detecting ketosis in humans and animals.
Ranbut measures the most abundant ketone body, D-3-hydroxybutyrate, which gives it advantages over nitroprusside methods that measure acetone and acetoacetate.
D-3-hydroxybutyrate is the most stable ketone body (~7 days at 4C) and increases the most during ketosis, meaning it is the most sensitive marker.
When carbohydrates are not available, fat is metabolised in the liver for energy production, resulting in the production of ketone bodies, consisting of acetone (two per cent), acetoacetate (20 per cent) and D-3-hydroxybutyrate (78 per cent).
Levels of ketone bodies in the blood are elevated (ketosis) when synthesis exceeds breakdown and can be life-threatening if untreated.
Monitoring for ketosis is important in many human and veterinary conditions, such as diabetes, hypoglycaemia, dieting, epilepsy, severe illness or injury, sepsis and twin lamb disease.
Detection of ketosis is most important in human healthcare in relation to diabetes, where the fall in D-3-hydroxybutyrate occurs ~two hours before the fall in blood glucose following insulin treatment.
This means monitoring D-3-hydroxybutyrate allows rapid detection of insulin over-treatment during intravenous therapy.
Many critically ill patients respond to starvation by metabolising fats and proteins, which leads to muscle wastage; this means monitoring ketone levels in these patients allows this problem to be diagnosed.
Ranbut helps to identify patients likely to benefit from nutritional support.
In a veterinary setting, high energy demand in animals - for example during pregnancy, milk production and immediately post-birth - may induce ketosis, leading to decreased milk yields, weight loss and infertility.
Ranbut can monitor animals at this time to ensure optimum health and production.
The Ranbut assay has high linearity to 3.2mmol/l, is highly sensitive (to 0.1mmol/l), is the only kinetic method for the measurement of D-3-hydroxybutyrate and has good stability of working reagents.
Ranbut uses serum rather than a urine sample, which eliminates the risk of false positives caused by drug interference.
Quality-control sera are also available for this test.