Canine Chronic Enteropathy: Diagnosis, Treatment, and Long-Term Management
By Tara Ghormley, DVM, DACVIM
Chronic gastrointestinal issues in dogs are frustrating for owners and clinicians alike. When diarrhea, vomiting, or weight loss last longer than three weeks and other causes have been excluded, veterinarians should consider a diagnosis of chronic inflammatory enteropathy (CIE). This condition, although nonspecific, is the most common cause of chronic GI signs in dogs and accounts for 1–2% of cases in referral hospitals.
What Does Chronic Enteropathy Look Like?
Dogs with CIE show a wide range of clinical signs: vomiting, diarrhea, weight loss, decreased appetite, nausea, abdominal pain, or even unusual behaviors like pica. Symptoms may be intermittent or persistent.
Any breed can be affected, though some breeds have an increased risk. German Shepherds, Yorkshire Terriers, and Cocker Spaniels are frequently represented, while Wheaten Terriers are prone to protein-losing enteropathy (PLE), Basenjis to immunoproliferative enteropathy, and Boxers/French Bulldogs to granulomatous colitis. The average age of onset is about 6 years, but even dogs under 2 may develop the condition.
Why Does It Happen?
The pathophysiology of CIE is complex and multifactorial:
Genetics: Certain breeds have predispositions.
Barrier defects: Damaged intestinal tight junctions allow harmless antigens to leak through, triggering inflammation.
Microbiome shifts: Changes in bacterial diversity and abundance (dysbiosis) can drive abnormal immune responses.
Immune dysfunction: Abnormal gut-associated lymphoid tissue (GALT) overreacts to normal dietary or microbial antigens.
Diagnosing CIE
Because CIE is a diagnosis of exclusion, a full workup is essential. Veterinarians typically start with:
Fecal testing to rule out parasites.
Minimum database labs. The finding of hypoproteinemia, hypocalcemia, and/or hypocholesterolemia suggest malabsorption; anemia may indicate blood loss.
Abdominal ultrasound may show intestinal wall changes or mesenteric lymphadenopathy, though results can be normal.
Vitamin tests. A low cobalamin or altered folate support malabsorption or dysbiosis.
Endoscopy and biopsy is the gold standard. Findings may include erythema, friability, erosions, or normal-appearing mucosa. Histopathology confirms inflammation but cannot distinguish CIE subtypes.
Two activity indices help track severity:
CIBDAI (Canine IBD Activity Index): evaluates activity, appetite, vomiting, stool, and weight loss.
CCECAI (Canine Chronic Enteropathy Clinical Activity Index): adds albumin, ascites, edema, and pruritus to the above indices.
Classifying Chronic Enteropathy
Classification of CIE is defined by treatment response rather than histopathology, as they often have similar microscopic findings. The four main categories are:
Food-Responsive Enteropathy (FRE):
The most common type (50–60%).
Typically affects dogs under 12 months.
Symptoms improve within 2 weeks of a hypoallergenic diet.
Prognosis is excellent, especially for large-bowel cases.
Antibiotic-Responsive Enteropathy (ARE):
Historically 15–35% of cases, diagnosed by improvement with antibiotics.
Today, evidence shows antibiotics disrupt the microbiome long-term.
True ARE may be rare and is better defined as microbiota-related modulation-responsive enteropathy.
Biotic therapies (pre/pro/syn/postbiotics) and fecal transplants are now preferred.
Immunosuppressant-Responsive Enteropathy (IRE):
Diagnosed when diet and biotic therapy fail.
Requires biopsy-proven inflammatory infiltrates, most often lymphoplasmacytic.
Treated with steroids (prednisone or budesonide) ± other immunosuppressants.
Non-Responsive Enteropathy (NRE):
Dogs that fail to respond to diet or immunosuppressants.
Prognosis is poor; small cell intestinal lymphoma may be a hidden cause.
Some breeds (e.g., Shiba Inu) are more prone to NRE.
A special subset, Protein-Losing Enteropathy (PLE), complicates any of the above categories. It results from lymphatic obstruction or leakage and requires an ultra-low-fat diet and occasionally immunosuppressants.
Management Approaches
Diet First
Nutrition is the cornerstone of therapy, and a food trial is considered part of the diagnostic workup of CIE. Options include hydrolyzed protein diets and novel protein diets. Dogs with chronic large bowel diarrhea may benefit from a high fiber gastrointestinal diet. Dogs initially classified as IRE may later respond to diet alone. Ultra-low-fat diets are critical in PLE, and many dogs achieve remission with food adjustments alone.
Immunosuppressant Options
Prednisone should be given at 2 mg/kg/day (max 60 mg), and tapered after 2–4 weeks to lowest dose possible.
Budesonide sometimes has comparable efficacy with fewer systemic effects.
Cyclosporine or chlorambucil are suitable for for resistant cases.
Octreotide is a somatostatin analog used as rescue therapy in severe PLE. Unfortunately it is not commonly used due to the cost of treatment.
Non-Specific Treatments
Biotics: Probiotics such as Visbiome (VSL#3) show some promise. Fecal microbiota transplants are still experimental but may help microbiota-driven cases.
Cobalamin supplementation: Deficiency is common (up to 75% in PLE). Supplementation is given by injection or orally and rechecked after treatment.
Folate, Vitamin D, and bile acid sequestrants address malabsorption, dysbiosis, or inflammation.
Antithrombotics: In PLE, the risk of thromboembolism is high. Drugs like clopidogrel or rivaroxaban may be used .
Prognosis
Outcomes vary widely:
Remission occurs in 57–100% of cases within 3 months.
Median survival time is >800 days for mild/moderate CIE, but shorter (~542 days) for severe cases.
For PLE: ~31% achieve long-term remission, 25% relapse, and 44% never achieve remission.
Relapses often occur from dietary indiscretion rather than disease progression.
Negative prognostic markers include:
Severe duodenal endoscopic changes.
Low cobalamin (<200 ng/L).
Hypoalbuminemia (<2 g/dL).
Severe vitamin D deficiency.
High CIBDAI (>9) or CCECAI (>12) scores .
Key Takeaways
CIE is not one disease but a spectrum, categorized by treatment response.
Dietary therapy is always first-line and often sufficient as a sole treatment.
Immunosuppressants are reserved for non-responders and true antibiotic-responsive enteropathy is increasingly rare.
PLE requires aggressive management with diet and antithrombotics. Occasionally immunosuppressants are required.
Long-term prognosis varies, but many dogs achieve remission with proper management.