Preliminary Notes on Equine Tissue Transglutaminase Serology and A Case of Equine Gluten-Sensitive Enteropathy and Dermatitis in an 11-Year-Old Dutch Warmblood Horse.

Abstract

It has been suggested that gluten may play a role in equine inflammatory small bowel disease (ISBD). Previous work showed an association between equine gluten-sensitive enteropathy and IgA antibodies to tissue transglutaminase (TGA) in serum. The purpose of this study is to investigate the prevalence of IgA antibodies to TGA in a group of healthy non-gluten-free sport ponies and to present a case of tentative gluten-sensitive enteropathy and dermatitis in a horse. Blood samples were obtained from 40 healthy jumping ponies. The ponies comprised 12 mares, 8 stallions, and 20 geldings with an average age of 9.0 &#xb1; 3.8&#xa0;years (&#xb1;SD; range 3-19&#xa0;years). Sera were tested for IgA antibodies against human recombinant TGA. Significance (P < .05) of the correlation between TGA titer and age in these ponies was assessed using Pearson test (two tailed). In addition, to further illustrate tentative equine gluten-sensitive enteropathy and dermatitis, the clinical course in an 11-year-old Dutch Warmblood sport horse gelding has been described. The average TGA titer was 21.4 &#xb1; 13.6 AU/mL (range 2-65 AU/mL). There was a significant (P&#xa0;= .013) correlation (r&#xa0;= 0.389) between age and TGA titer in ponies. One of the 40 ponies (2.5%) showed an elevated TGA titer. An elevated TGA titer decreased after a gluten-free ration for 3&#xa0;months in an 11-year-old Warmblood gelding with a tentative diagnosis of ISBD associated with full remission of the generalized skin reaction. To our best knowledge, this is the first study assessing TGA antibodies in sera from healthy non-gluten-free ponies and showing a correlation with age. The presented case could be the first one of a horse with a tentative diagnosis of gluten-sensitive enteropathy combined with dermatitis. Given the reported findings, this study warrants further investigations into gluten-sensitive enteropathy and dermatitis in individual horses affected with ISBD.