Background

A panel of IgA-based serologic assays might aid in the diagnosis of chronic enteropathy (CE) in dogs, a syndrome encompassing conditions such as food-responsive enteropathy, immunosuppressant-responsive enteropathy, and inflammatory bowel disease (also referred to as chronic inflammatory enteropathy). However, it is unclear whether these biomarkers discriminate between CE and other types of primary intestinal disorders.

Objectives

To evaluate a diagnostic panel that measures serum concentrations of IgA directed against OmpC (ACA), canine calprotectin (ACNA), and gliadin-derived peptides (AGA) in dogs with well-characterized intestinal diseases.

Animals

Fifty-five dogs with primary intestinal disease.

Methods

Serum ACA, ACNA, and AGA concentrations were measured in 30 dogs with CE and 25 dogs with other intestinal diseases (non-CE population), including histoplasmosis, parasitism, E. coli-associated granulomatous colitis, and lymphoma. Serum IgA concentrations were compared among populations, and sensitivities and specificities were calculated using laboratory-provided cut-points.

Results

Twenty-six of 30 (87%) CE dogs and 21 of 25 (84%) non-CE dogs had abnormal concentrations (intermediate or high) of at least 2 markers; these proportions were not significantly different (P = .99). A serum ACA concentration ≥15 EU/mL was 86.7% (95% confidence interval [CI], 69.3%-96.2%) sensitive and 24.0% (95% CI, 9.4%-45.1%) specific for CE diagnosis. High AGA concentrations were observed in 16 of 25 (64%) non-CE dogs.

Conclusions and clinical importance

The evaluated serologic markers were poorly specific for CE diagnosis, which raises concerns that their use in clinical practice might lead to misdiagnoses and delayed or even detrimental treatments in dogs with non-CE intestinal diseases.

Background

Copper associated hepatitis (CAH) has been increasingly recognized in dogs, and speculation exists that hereditary defects in copper metabolism have been exacerbated by increased environmental copper exposure. However, no broad epidemiological investigations have been performed to investigate quantitative hepatic copper concentrations ([Cu]_H ) over time in both dogs that are (predisposed breed [PB]), and are not (non-predisposed breed [NPB]), considered at-risk for CAH.

Objectives

To investigate [Cu]_H in dogs and explore temporal, demographic, and histologic associations spanning 34 years.

Animals

546 archived liver specimens.

Methods

Retrospective study. Searches of the Michigan State University Veterinary Diagnostic Laboratory database identified dogs that had undergone hepatic histopathologic assessment. Cases with archived tissue were reviewed and classified by breed, time period, and presence or absence of hepatitis. Inductively coupled plasma mass spectrometry was used to determine [Cu]_H .

Results

In time period 2009-2015, median [Cu]_H were 101 μg/g and 313 μg/g greater than median [Cu]_H in time period 1982-1988 for NPB and PB dogs, respectively (P < .001 for both comparisons). The proportion of dogs with [CU]_H > 300 μg/g increased in NPB (28% to 49%) and PB dogs (48% to 71%) during these periods (P = .002 for both comparisons). Median [Cu]_H in dogs with hepatitis increased 3-fold over time in both NPB (P = .004) and PB populations (P < .001).

Conclusions and clinical importance

The frequent recognition of CAH in recent years is likely due to the observed increases in [Cu]_H over time. Importantly, effects are not limited to PB dogs.