At the time of the examination your client was dieting. Significantly, this was a high protein, fasting, low carb, keto diet.
This type of ketogenic dieting results in the metabolism of fat which produces ketones. Ketones also can impart a sweet or fruity odor to the breath, which may be mistaken for alcohol which may mimic indicia of intoxication. In addition, ketones can cause drowsiness.
The ketone production leads to ketoacidosis. The ketones in ketoacidosis are a form of acetone. “Acetone may be converted to isopropanol in physiological conditions…,” (Detection of Isopropanol In Acetonemic Patients Not Exposed to Isopropanol by David N. Baily, MD of the Division of Laboratory Medicine, Department of Pathology, University of California Medical Center, San Diego, California, according to the article published in Clinical Toxicology, 28(4).459-466, (1990). The journal Clinical Toxicology is a peer reviewed journal. Additional publications in peer reviewed journals support these findings. For example, “…The detection of isopropyl alcohol may not represent an acute ingestion but, rather, a byproduct of acetone metabolism in certain disease states…” which appeared in Detection of Isopropyl Alcohol In A Patient With Diabetic Ketoacidosis by Alan E. Jones and Richard L. Summer, MD in the Journal of Emergency Medicine, Vol.19, No. 2 pps. 165-168, 2000, support these findings. The Journal of Emergency Medicine is also a peer reviewed journal.
Ketone bodies include acetone, acetoacetate and Beta-hydroxybutyrate. “…Under certain circumstances acetone is reduced in the body to isopropanol by hepatic alcohol dehydrogenase (ADH)” A.W. Jones and S. Rossner False-positive breath – alcohol test after a ketogenic diet, International Journal of Obesity (2007) 31, 559-561. Isopropanol is an alcohol that can be detected by evidentiary breath testing equipment.