Neoplasia is listed as a differential diagnosis for chronic diarrhea. Which statement is true?

• A. Neoplasia
• B. Chronic inflammatory enteropathy
• C. Toxins
• D. Hypoperfusion

Answer: (A)

Chronic diarrhea can arise from a range of causes, and neoplasia is one of the potential culprits to consider. Tumors in the gastrointestinal tract can disrupt normal mucosal function, absorption, and motility, leading to persistent, sometimes malabsorptive or secretory diarrhea. They may present with subtle or gradual signs such as weight loss, poor appetite, vomiting, abdominal discomfort, or intermittent diarrhea, and in some cases a palpable mass or segmental thickening is seen on imaging.

In practice, if diarrhea is chronic and not explained by more common inflammatory or infectious causes, veterinarians look for clues that raise suspicion for neoplasia: older age, progressive symptoms despite standard therapy, and imaging findings like focal intestinal thickening or a discrete intraluminal or mural mass, sometimes with regional lymphadenopathy. Definitive diagnosis usually requires tissue biopsy obtained via endoscopy or surgery, with histopathology allowing distinction from inflammatory enteropathy.

Chronic inflammatory enteropathy remains a frequent and important differential for chronic diarrhea, but recognizing that neoplasia can underlie persistent signs prompts appropriate diagnostic steps, including imaging and biopsy, to guide treatment. Toxins and hypoperfusion more commonly cause acute or subacute GI symptoms or systemic signs rather than a straightforward chronic diarrhea picture, so while they can contribute in specific scenarios, neoplasia is a recognized differential that warrants consideration in the right clinical context.