Breath Acetone Analysis of Diabetic Dogs Using a Cavity Ringdown Breath Analyzer

Some dogs develop a form of diabetes mellitus (DM) similar to that seen in children (juvenile, or Type 1 DM). It is characterized by concurrent high blood glucose (BG) and urine glucose concentrations. Elevated breath acetone concentrations have been observed in Type 1 DM in humans, though a quantitative correlation between breath acetone and BG has yet to be determined. The study of breath acetone in diabetic dogs might allow the use of breath acetone as a biomarker for diabetes in both humans and animals. We report on breath acetone analysis of 51 dogs (37 nondiabetic dogs and 14 diabetic dogs). Breath samples were collected and simultaneous BG levels (if applicable) were measured. Breath acetone tests were conducted using a real-time breath acetone analyzer that is based on the cavity ringdown spectroscopy technique. Absolute breath acetone concentrations (upper limits) were determined without the need for breath sample preconcentration and measurement calibration. For the 37 nondiabetic dogs, their exhaled breath acetone concentrations ranged from 0.16 to 2.42 parts per million (ppm). For the 14 diabetic dogs, breath acetone concentrations ranged from 0.17 to 5.80 ppm with a BG range of 30-750 mg/dL. The mean breath acetone concentration in the 14 diabetic dogs is 1.25 ppm, which is higher than that in the 37 nondiabetic dogs, i.e., 0.60 ppm. The mean breath acetone concentration in nondiabetic dogs, 0.60 ppm, is close to the mean breath acetone concentration in healthy humans. Although diabetic dogs exhibit elevated mean breath acetone concentration, as in human Type 1 DM, no correlation was found between breath acetone concentration and BG level in the diabetic dogs in this paper.