Protein‑Losing Enteropathy (PLE) in Cats: Vet Guide 🐱💧 2025

By Dr Duncan Houston BVSc, veterinarian & founder of Ask A Vet.

Protein‑Losing Enteropathy (PLE) is a syndrome where cats lose excessive plasma proteins into the intestine—exceeding replacement—leading to low blood protein, fluid loss, and potentially life-threatening complications. Though less common in cats than dogs, recognizing PLE and addressing its causes promptly is vital for your feline's health. This guide walks you through:

• 🔍 What PLE is and how proteins are lost from the bloodstream
• 🧬 Key causes—ranging from IBD and lymphoma to lymphatic dysfunction
• 🚨 Signs & complications like diarrhea, weight loss, edema, ascites
• 🧪 Thorough diagnostic protocol—labs, imaging, biopsy
• 💊 Treatments tailored to cause—including diet, meds, surgery
• 🥗 Diet strategies & nutritional support
• 📆 Prognosis, follow‑up, and long‑term management
• 🤝 How Ask A Vet telehealth supports you through every step

🔍 What Is Protein‑Losing Enteropathy?

In healthy cats, minimal protein leaks into the intestines and is reabsorbed. But in PLE—due to inflammation, neoplasia, lymphatic drainage issues—large amounts of serum proteins like albumin and globulins remain in the gut lumen and are lost through feces :contentReference[oaicite:3]{index=3}.

This results in:

• Hypoalbuminemia & hypoglobulinemia: low blood protein and weakened immunity
• Reduced oncotic pressure: fluid leaks into tissues—causing edema or ascites :contentReference[oaicite:4]{index=4}
• Extraintestinal signs: respiratory distress, clotting issues from protein loss :contentReference[oaicite:5]{index=5}

🧬 Common Causes of PLE in Cats

PLE isn't a single disease—it's a sign of various underlying issues:

• Inflammatory Bowel Disease (IBD): chronic mucosal inflammation increasing permeability :contentReference[oaicite:6]{index=6}
• Gastrointestinal lymphoma: lymphosarcoma is the most frequent feline cancer-type causing PLE :contentReference[oaicite:7]{index=7}
• Lymphangiectasia: abnormal lymph flow (primary or secondary, e.g., due to heart disease) :contentReference[oaicite:8]{index=8}
• Parasitic infection: e.g., Strongyloides, hookworms in young or stray cats :contentReference[oaicite:9]{index=9}
• Infection or ulceration: fungal, bacterial, viral agents
• Neoplasia or structural lesions: carcinoma, tumours, chronic ulceration
• Cardiac-related: congestive or constrictive pericarditis causing lymphatic backup :contentReference[oaicite:10]{index=10}

🚨 Clinical Signs & Complications

🧪 Diagnostic Approach

1. History & physical exam: chronic GI signs, weight loss, edema, fluid wave.
2. Bloodwork: CBC, chemistry—including low albumin/globulin, assessing liver and kidney values, electrolytes, cobalamin/folate :contentReference[oaicite:14]{index=14}.
3. Urinalysis: rule out kidney-related protein loss.
4. Fecal tests: flotation, PCR for parasites.
5. Imaging:
   • Ultrasound: thickened intestines, mesenteric lymphadenopathy, intestinal lymphangiectasia (striated mucosa) :contentReference[oaicite:15]{index=15}
   • X-ray for obstruction or tumor mass.
6. Alpha-1‑antitrypsin fecal test: quantifies GI protein loss :contentReference[oaicite:16]{index=16}.
7. Endoscopy or surgical biopsy: gold standard—allows histopathology to confirm IBD, lymphoma, lymphangiectasia :contentReference[oaicite:17]{index=17}.

💊 Treatment Options

1. Treat Underlying Cause

• IBD: dietary trials (novel/hydrolyzed protein), immunosuppressives (corticosteroids, chlorambucil) :contentReference[oaicite:18]{index=18}.
• Lymphoma: surgical resection and/or chemotherapy; prognosis depends on stage.
• Lymphangiectasia: low-fat diet, ± steroid therapy to reduce inflammation.
• Parasites: appropriate deworming based on diagnosis.
• Cardiac-related: manage pericardial/heart disease to reduce lymph pressure.

2. Supportive Care

• IV/subcutaneous fluids to correct dehydration/protein loss.
• Electrolytes—supplement potassium/magnesium if needed.
• Appetite support: antiemetics (maropitant), vitamin B12 injections.
• Pain control if ulceration or inflammation present.
• Diuretics in cases with effusion—carefully monitored by vets.
• Omega‑3 and medium‑chain triglyceride supplements to support gut healing.

3. Nutritional Management

• Novel/hydrolyzed protein diet to reduce antigenic stimulus.
• Low-fat diet for lymphangiectasia; include MCT oil and omega‑3s.
• Gradual diet transitions over 7–14 days to avoid GI upset :contentReference[oaicite:19]{index=19}.
• High-calorie support in hypoalbuminemic cats, including palatable wet diets.

📆 Prognosis & Follow‑Up

• Severe PLE has guarded prognosis—especially with lymphoma or protein loss >3 g/dL.
• IBD and lymphangiectasia respond well to therapy; remission possible with long-term diet and steroids :contentReference[oaicite:20]{index=20}.
• Monitor albumin, globulin, weight and GI signs every 2–4 weeks initially, then 3–6 months.
• Repeat imaging if signs recur.
• Relapses may require diet re‑trial, steroids, or antimicrobials.

🛡️ Prevention & Management

• Ongoing dietary management is key: consistent, prescription GI diets.
• Prevent parasite exposure with routine deworming (monthly).
• Manage cardiac diseases to reduce lymph pressure.
• Protecting gut lining—stress management, avoid NSAIDs, use gut-healing supplements.

📱 Role of Ask A Vet Telehealth

Ask A Vet supports you by:

• 📋 Reviewing lab results, symptoms, and imaging remotely
• 💬 Offering guidance on diet selection, steroid tapering, medication adjustments
• 🔄 Monitoring clinical response and guiding when in‑hospital care is needed
• 📅 Scheduling follow-ups to detect relapse early
• 🔧 Answering questions about deworming, fluid therapy, supplements

✅ Key Takeaways

• PLE is a serious syndrome—candidates: IBD, lymphoma, lymphangiectasia, parasites, cardiac disease.
• Signs include diarrhea, weight loss, edema, and low blood protein.
• Diagnosis requires labs, imaging, fecal alpha‑1‑antitrypsin, and biopsy.
• Treatment involves addressing the root cause, supportive care, and tailored nutrition.
• Prognosis varies—best for IBD/lymphangiectasia; guarded for lymphoma.
• Ask A Vet telehealth ensures the right treatment and monitoring every step of the way.

📞 Final Thoughts

Protein‑Losing Enteropathy in cats can be life-threatening—but early detection, cause‑specific treatment, dedicated supportive care, and expert guidance make remission possible. With Ask A Vet’s telehealth support, you can confidently manage your cat’s health and help them thrive. 😊

Need help interpreting labs, choosing a GI diet, or tracking recovery? Visit AskAVet.com and download the Ask A Vet app for full telehealth support!