Peritonitis in Cats

Peritonitis in cats is a serious condition characterized by inflammation of the peritoneum, the thin membrane that lines the abdominal cavity and surrounds internal organs. This inflammation can occur due to infections, injuries, or secondary to other diseases, and it requires immediate medical attention to prevent life-threatening complications. 

Peritonitis in Cats

Peritonitis is the inflammation of the peritoneum, a thin layer of tissue that lines the abdominal cavity and encloses the abdominal organs. This condition can arise when bacteria, fungi, or viruses enter the abdominal cavity, leading to infection and inflammation. The inflammation can be localized or spread throughout the abdominal cavity.

The two main types of peritonitis are:

• Infectious Peritonitis:
  Caused by bacterial, viral, or fungal infections. One well-known form of infectious peritonitis in cats is Feline Infectious Peritonitis (FIP), which is caused by a mutation of the feline coronavirus.
• Non-Infectious Peritonitis:
  Results from trauma, such as injuries to the abdomen, or ruptures of internal organs like the intestines or bladder. Non-infectious peritonitis can occur without the presence of pathogens, but it can lead to infection if not treated promptly.

Causes of Peritonitis in Cats

There are several potential causes of peritonitis in cats, including:

1. Feline Infectious Peritonitis (FIP):
FIP is a complex and fatal disease caused by a mutation of the feline coronavirus. It is the most common cause of infectious peritonitis in cats and has two forms: the wet form and the dry form. The wet form causes fluid buildup in the abdominal cavity, leading to severe inflammation of the peritoneum.

2. Trauma:
Blunt or penetrating injuries to a cat’s abdomen, such as being hit by a car or falling from a height, can cause internal organ damage and lead to peritonitis.

3. Gastrointestinal Perforation:
Perforation of the intestines, stomach, or colon can occur due to foreign objects being ingested, severe infections, or ulcers. This can allow bacteria to escape into the abdominal cavity, causing peritonitis.

4. Ruptured Bladder or Uterus:
A ruptured bladder due to urinary blockage or a ruptured uterus (usually due to complications during pregnancy) can cause urine or other fluids to leak into the abdominal cavity, triggering peritonitis.

5. Liver or Gallbladder Issues:
If the liver or gallbladder ruptures or leaks, bile can enter the abdominal cavity and cause inflammation.

6. Infections from Surgery:
Surgical procedures that involve the abdominal organs (e.g., spaying, exploratory surgery) may introduce bacteria into the abdomen, leading to post-operative peritonitis if complications arise.

Symptoms of Peritonitis in Cats

Peritonitis can present with a wide range of symptoms depending on its severity, cause, and whether the condition is infectious or non-infectious. Cats with peritonitis often show signs of severe illness, which may progress rapidly. Here are some common symptoms:

1. Abdominal pain and swelling:
Cats with peritonitis often experience severe abdominal discomfort. They may exhibit signs such as sensitivity to touch, a hunched posture, or vocalizing when the abdomen is touched.

2. Lethargy:
Cats suffering from peritonitis tend to be extremely lethargic, uninterested in their surroundings, and may isolate themselves.

3. Vomiting and diarrhea:
Digestive issues such as vomiting, diarrhea, or constipation are common in peritonitis cases, especially if the gastrointestinal tract is involved.

4. Loss of appetite (anorexia):
Cats with peritonitis may refuse food or water, leading to rapid weight loss and dehydration.

5. Fever:
A high fever may be present, especially in infectious cases of peritonitis. However, if the infection becomes overwhelming, the body may lose the ability to maintain a fever, leading to a drop in body temperature.

6. Dehydration:
Dehydration is common due to vomiting, diarrhea, and a lack of water intake.

7. Difficulty breathing:
In cases of FIP, particularly the wet form, fluid buildup in the abdominal or thoracic cavities can cause breathing difficulties.

8. Jaundice:
If the liver is affected or if bile leaks into the abdomen, the cat’s gums and eyes may turn yellow (jaundice).

9. Shock:
In advanced cases, cats may go into septic shock, characterized by pale gums, a rapid heart rate, cold extremities, and collapse. This is a life-threatening emergency.

Can a Cat Survive Peritonitis?

The prognosis for cats with peritonitis depends heavily on the underlying cause, the speed of diagnosis, and the aggressiveness of treatment. Cats with mild cases of non-infectious peritonitis may recover if treated early. However, the survival rate for infectious peritonitis, especially FIP, is much lower.

Feline Infectious Peritonitis (FIP):
FIP, particularly the wet form, is almost always fatal if left untreated. Recent advances in antiviral drugs, like GS-441524, have shown promise in treating FIP, with some cats surviving and recovering after undergoing treatment. However, access to these treatments may be limited due to regulatory constraints, and the cost can be high.

Non-FIP Infectious Peritonitis:
If the cause of peritonitis is bacterial or fungal, and the infection is localized, aggressive treatment with antibiotics, antifungals, and possibly surgery can lead to recovery. However, this requires early diagnosis, and the infection must not have progressed to sepsis (a systemic infection).

Non-Infectious Peritonitis:
If peritonitis is caused by trauma, organ rupture, or surgical complications, cats may survive if they receive prompt surgical intervention and supportive care. The success rate depends on the extent of the damage and whether the condition was caught before infection set in.

Treatment for Peritonitis in Cats

The treatment of peritonitis in cats depends on the underlying cause, but it is generally a medical emergency requiring immediate veterinary care. Here are the typical treatment options:

1. Stabilization

Cats with peritonitis are often in critical condition and require stabilization before any definitive treatment can be initiated. This typically includes:

• Intravenous (IV) fluids: To address dehydration and shock.
• Pain management: Strong pain relief medications are used to keep the cat comfortable.
• Nutritional support: Cats that refuse to eat may need assisted feeding or a feeding tube.

2. Antibiotics or Antifungal Medication

If the peritonitis is caused by a bacterial or fungal infection, broad-spectrum antibiotics or antifungal medications are administered while waiting for the results of cultures to identify the specific pathogen.

3. Surgery

In many cases of peritonitis, surgery is required to address the underlying cause. This may involve:

• Repairing organ damage:
  Surgery may be needed to repair ruptured intestines, bladder, or other abdominal organs.
• Removing foreign objects:
  If a foreign body is causing peritonitis, it must be surgically removed.
• Drainage of infected fluid:
  In cases of infectious peritonitis, abscesses or fluid buildup may need to be drained.

4. Supportive Care

After surgery or during treatment, cats require intensive supportive care. This can include:

• Oxygen therapy:
  For cats with respiratory distress, particularly those with fluid buildup in the chest (as seen in FIP).
• Anti-inflammatory medications:
  To reduce inflammation and pain.
• Nutritional support:
  If the cat cannot eat on its own, it may need intravenous nutrition or a feeding tube.

5. Feline Infectious Peritonitis (FIP) Treatment

For cats diagnosed with FIP, particularly the wet form, the treatment landscape has improved with the use of antiviral drugs like GS-441524. While these treatments are not yet widely approved, some veterinarians have had success using them off-label, and clinical trials are ongoing.

Conclusion

Peritonitis in cats is a grave condition that requires prompt recognition and aggressive treatment. The outcome for a cat with peritonitis largely depends on the underlying cause and the speed of intervention. Cats with non-infectious peritonitis or treatable infections have a higher chance of survival, but the prognosis for those with Feline Infectious Peritonitis (FIP) remains poor without advanced treatments. For any cat displaying symptoms of peritonitis, immediate veterinary care is essential to maximize the chances of recovery.