Assessment of disease severity and outcome of dietary, antibiotic, and immunosuppressive interventions by use of the canine IBD activity index in 21 dogs with chronic inflammatory bowel disease

Recently, the canine IBD activity index (CIBDAI) was developed for evaluation of the severity of illness, therapeutic strategies, and efficacy of therapy.The aim of the present study was to assess the severity of illness and the therapeutic strategy in dogs with IBD by the use of CIBDAI, serum albumin concentration, and histologic score (HPEG). Furthermore the use of CIBDAI and the efficacy of therapy in a prospective study during a 3 month treatment period were evaluated. Twentyone dogs with inflammatory bowel disease (lymphocytic-plasmacytic enteritis and enterocolitis) were examined in this study. In 11 dogs with IBD the severity of illness was assessed as low, according to CIBDAI and HPEG (CIBDAI score 4 or between 5 and 10 with HPEG score between 1 and 1.5). Six dogs were treated with hypoallergenic diet (Group D), five dogs were treated with hypoallergenic diet and metronidazole (15.6-22,3 mg/kg/day) (Group M). In 10 dogs with IBD the severity of illness was assessed as high (CIBDAI <10, or CIBDAI between 5 and 10 with HPEG score between 2 and 3 or hypoalbuminemia (< or = 2.5 g/dl)). This group (Group I) was treated with immunosuppressive therapy.Treatment consisted of prednisolone (n=10; 0.9-2 mg/kg/day), azathioprine (n=5; 0.9-2.3 mg/kg/day), sulfasalazine (n=4; 18.2-25 mg/kg/day) and hypoallergenic diet (n=10). Efficacy of therapy was evaluated prospectively 3 times in a 12 weeks treatment period. Remission (CIBDAI score < 4) indicated good therapeutic response, chronic or recurrent disease (CIBDAI score persistent or recurrent > or =4) indicated poor therapeutic response. Age, CIBDAI score and HPEG score were significantly different in IBD dogs with low severity of illness (age: median 60 months; CIBDAI score: median 5; HPEG score: median (1) and IBD dogs with high severity of illness (age: median 90 months; CIBDAI score: median 9.5; HPEG score: median 2.25) (p = 0.0101 and p = 0.0099, respectively). The presence of hypoalbuminemia was not significantly different between these two groups (p = 0.3108). There was no significant correlation between CIBDAI score and serum albumin concentration (r = 0.0394; p = 0.0802) or between CIBDAI score and HPEG score (r = 0.2587; p = 0.2574). In the treatment groups, HPEG score was only significantly different between D-group and group I (p < 0.01). The CIBDAI score decreased significantly in group I after 4 weeks of treatment (median 4th week: 3; p < 0.05), and in the D-group after 8 weeks of treatment (median 8" week 1; p < 0.05). No significant decrease of CIBDAI score was seen in the M-group (median 12th week: 1.75; p > 0.05). All dogs in group D, four of five dogs in group M, and six from ten dogs in group I went into remission. Poor therapeutic response (1 dog in group M and 5 dogs in group I; one dog died) was seen in 6 dogs, where as 15 dogs showed good therapeutic response. There was no significant association between efficacy of therapy and age (p = 0.8455), CIBDAI score (p = 0.3293), or serum albumin concentraton (p = 0.8455). Poor therapeutic response was weekly associated with HPEG score > or =2 (p = 0.0635). Using CIBDAI in dogs with IBD as a single parameter to assess the severity of illness and the therapeutic response, misinterpretations are possible.The assessment of the severity of illness by the combination of CIBAI, HPEG, and serum albumin concentration is leading to adaequate therapeutic results. Dogs with low grade IBD benefit from hypoallergenic diet, whereas dogs with high grade IBD benefit from immunosuppressive therapy. The effect of antibiotic treatment is questionable.