The mean cell volume difference (dMCV) reflects serum hypertonicity in diabetic dogs

Area of Science:

• Veterinary Medicine
• Clinical Pathology
• Endocrinology

Background:

• Serum hypertonicity, often linked to hyperglycemia in diabetes mellitus, can cause adverse cellular and systemic effects.
• The mean cell volume difference (MCV) is a novel erythrocyte measure that increases with serum hypertonicity in non-diabetic dogs.
• It remains unknown if hyperglycemic hypertonicity affects MCV in diabetic dogs.

Purpose of the Study:

• To investigate if the mean cell volume difference (MCV) can detect serum hypertonicity in dogs with naturally-occurring diabetes mellitus.
• To determine the effect of hyperglycemia on MCV in diabetic dogs.
• To assess the predictive ability of MCV for serum hypertonicity in diabetic canines.

Main Methods:

• Prospective recruitment of thirty-two dogs with naturally-occurring diabetes mellitus over one year.
• Examination of serum hyperosmolality and hypertonicity, correlating them with serum glucose levels.
• Analysis of the mean cell volume difference (MCV) as a potential marker for serum hypertonicity, using a cut-off value of ≥ 3 μm³.

Main Results:

• Serum hyperosmolality and hypertonicity were present in 91% and 94% of diabetic dogs, respectively, primarily caused by hyperglycemia.
• Using a cut-off of ≥ 3 μm³, MCV identified serum hypertonicity (≥ 320 mmol/kg) with 79% sensitivity and 61% specificity.
• Elevated MCV (≥ 3 μm³) correlated with increased risk for clinically relevant serum tonicity (RR=2.2) and hyperglycemia (RR=2.3).

Conclusions:

• The mean cell volume difference (MCV) serves as a valuable surrogate marker for detecting serum hypertonicity in diabetic dogs.
• An elevated MCV is associated with a higher risk of significant hypertonicity and hyperglycemia in diabetic canines.
• This erythrocyte measure aids in assessing the impact of hyperglycemia on serum tonicity in veterinary diabetes mellitus cases.