Codocytosis in the Dog: 345 Cases (2020-2022).

Area of Science:

• Veterinary Hematology
• Canine Pathology
• Erythrocyte Morphology

Background:

• Codocytes, or target cells, are erythrocytes with increased surface area to volume ratio.
• The clinical significance of codocytosis in dogs is not well-established.
• Codocytosis is a common finding in routine canine blood smear evaluations.

Purpose of the Study:

• To investigate the clinical conditions associated with canine codocytosis.
• To assess the relationship between codocyte severity and hematologic, biochemical, and diagnostic findings.
• To understand the clinical relevance of codocytes in dogs.

Main Methods:

• Retrospective study of 345 dogs with codocytosis (grade ≥2+).
• Data collected included complete blood counts (CBCs), serum biochemistry, diagnoses, and medications.
• Codocytosis was semi-quantitatively graded (2+ to 4+); statistical analyses were performed.

Main Results:

• Codocytosis (≥2+) occurred in 2.5% of canine CBCs.
• Higher codocyte grades (3+ or 4+) correlated with elevated alanine transferase (ALT) and increased diagnoses of hepatobiliary and gastrointestinal diseases.
• Endocrine diseases, particularly diabetes mellitus, and antibiotic use were also associated with higher codocyte grades.

Conclusions:

• Canine codocytosis is associated with hepatobiliary, gastrointestinal, and endocrine diseases, rather than anemia or regeneration.
• The pathogenesis likely involves multifactorial processes, including altered lipid metabolism and membrane remodeling.
• Recognizing codocytosis can aid in identifying underlying systemic diseases in dogs.