Peritonitis is an inflammation of the peritoneum, the thin membrane that lines the abdominal wall and covers most of the organs of the body. There are two major types of peritonitis. Primary peritonitis is caused by the spread of an infection from the blood and lymph nodes to the peritoneum. This type of peritonitis is rare – less than 1% of all cases of peritonitis are primary. The more common type of peritonitis, called secondary peritonitis, is caused by the entry of bacteria or enzymes into the peritoneum from the gastrointestinal or biliary tract. Both cases of peritonitis are very serious and can be life-threatening if not treated properly.

The signs and symptoms of peritonitis include:

• Swelling and tenderness in the abdomen; pain can range from dull aches to severe, sharp pain causing board-like rigidity
• Fever and chills
• Loss of appetite
• Nausea and vomiting
• Increased breathing and heart rates
• Shallow breaths
• Low blood pressure
• Limited urine production
• Inability to pass gas or feces

The cause of primary peritonitis is infection in the blood. It occurs most commonly in individuals with liver disease. Fluid accumulates in the abdomen, creating a prime environment for the growth of infectious microorganisms. Secondary peritonitis is caused by the spillage of bacteria, enzymes, or bile into the peritoneum from a hole or tear in the gastrointestinal or biliary tracts. Such tears can occur as a result of an infected organ, such as a ruptured appendix, or as a complication from surgery.

The following factors may increase an individual's risk for primary peritonitis:

• Liver disease (cirrhosis)
• Kidney damage
• Fluid in the abdomen
• Compromised immune system 
• Pelvic inflammatory disease 

Risk factors for secondary peritonitis include:

• Appendicitis (inflammation of the appendix)
• Stomach ulcers
• Torn or twisted intestine 
• Severely inflamed gallbladder 
• Damage to the pancreas
• Inflammatory bowel disease, such as Crohn's disease or ulcerative colitis 
• A twisted intestine that can cause obstruction 
• Injury caused by an operation
• Continuous ambulatory peritoneal dialysis (CAPD) – a procedure used for people with end-stage renal disease 
• Trauma 

Given that peritonitis can be a life-threatening condition, the physician will first conduct a physical examination to determine whether surgery to correct the underlying problem is necessary. During the physical exam, the physician will feel and press the abdomen to detect any swelling and tenderness in the area as well as signs that fluid has collected in the area. He or she may also listen to bowel sounds and check for difficulty breathing, low blood pressure, and signs of dehydration. The following procedures may be included to confirm the diagnosis of peritonitis:

• Blood tests – identifies the microorganism causing the condition
• Samples of fluid from the abdomen – identifies the microorganism causing the condition
• CT scan – identifies fluid in the abdomen, an accumulation of pus, or an infected organ
• Chest X rays – detects air in the abdomen, which indicates that a torn or perforated organ may be present
• Peritoneal lavage – large amounts of fluid may be injected into the peritoneum and removed to wash out any microorganisms causing the condition

The best way to prevent serious complications associated with peritonitis is to seek medical attention as soon as symptoms appear.

Peritonitis is a potentially life-threatening condition that requires immediate medical attention. Hospitalization is common. Surgery is often necessary to remove the source of infection, such as an inflamed appendix, or to repair a tear in the walls of the gastrointestinal or biliary tract. Antibiotics are prescribed to control infection and intravenous therapy is used to restore hydration. Once these steps have been taken, some dietary supplements, including glutamine and arginine, omega-3 and omega-6 fatty acids, vitamins A, E, and C, zinc, and various Chinese herbs may be used in addition to antibiotics to aid in the healing process, particularly during recovery.

Medications

The following medications are prescribed to control infection and reduce pain associated with peritonitis:

Antibiotics 

Antibiotic medications inhibit the growth of microorganisms and prevent further spread of infection. The antibiotics prescribed vary, depending on the type of peritonitis and the organism causing the condition.

Morphine 

Morphine may be prescribed in the hospital to reduce pain.

Surgery and Other Procedures

Surgery is often necessary for individuals with both primary and secondary peritonitis. It can be the fastest and most effective way to remove infectious agents and repair damaged organs. Most surgical procedures are designed to locate the source of the bacterial infection, to drain excess fluid, and to remove or repair damaged tissue.

Nutrition and Dietary Supplements

Many studies have been conducted to determine whether dietary supplements can control the spread of infection associated with peritonitis. The following supplements show promise in the prevention and treatment of peritonitis:

Glutamine and Arginine (amino acids)

Several studies indicate that a diet supplemented with glutamine may protect the lining of the intestine (which reduces the possibility of tears), inhibit the growth of bacteria, and improve survival rates in animals with peritonitis. Similar results were found in animals that consumed diets high in arginine. Other studies of patients at high risk for infection suggest that diets high in glutamine, arginine, and omega-3 fatty acids may lower the risk of infection by more than 50%, shortening the length of hospital stay. These results are controversial, however, as the mechanism by which these supplements appear to work involves an inflammatory response in the peritoneum – a reaction known to cause peritonitis.

Omega-3 and Omega-6 Fatty Acids

Omega-3 fatty acids, found in cold-water fish such as salmon and mackerel, improve resistance to infection and therefore may aid in the healing of peritonitis. Results of one animal study also suggest that a proper balance of omega-3 and omega-6 fatty acids (found in some vegetable oils) may reduce the symptoms of peritonitis more effectively than either type of essential fatty acid alone. These results have yet to be confirmed in humans.

Vitamin A

Animal studies indicate that vitamin A may enhance the immune system and inhibit the growth of bacteria. Some researchers suggest that vitamin A supplementation may prove to enhance the effects of antibiotic therapy for peritonitis in humans, but studies with people are needed before a definitive conclusion can be made.

Vitamin D

Some research indicates that vitamin D may contribute to improved immune defenses within the peritoneal cavity for those on CAPD.

Vitamins E and C

Animal studies suggest that antioxidant nutrients, such as vitamins E and C, may boost the immune response and protect the body against some secondary complications of peritonitis, such as respiratory infection.

Zinc

Zinc is known to play an important role in maintaining immune function, and some researchers suggest that supplementation may aid in the healing process.

Herbs

In China, the following herbal formula is used in conjunction with antibiotics to treat peritonitis associated with CAPD:

• Bupleurum (Bupleuri falcatum L)
• Skullcap (Scutellaria lateriflora)
• Bitter orange (Citrus aurantium)
• Pinelliae tuber (Pinelliae ternata)
• Peony root (Paeoniae lactiflora)
• Corydalis root (Corydalis rhizoma)
• Rhubarb (Rheum palmatum)
• Honeysuckle flower (Lonicerae flos)
• Dandelion (Taraxacum officinale)

In addition, professional herbalists typically would not recommend herbs as the primary treatment for peritonitis, but they may recommend the following as a therapy to supplement conventional medicine:

• Echinacea root (Echinacea purpurea) – to boost the immune system
• Mushrooms, such as reishi (Ganoderma) – to boost the immune system
• Milk thistle (Silymarin officinalis) – to protect the liver
• Nettles (Urtica dioca) – to protect the liver

Homeopathy

The use of homeopathic remedies for the treatment of peritonitis has yet to be thoroughly scientifically evaluated, but a trained specialist may recommend the following:

• Deadly nightshade (Belladonna) – for individuals who are hypersensitive to touch, have sudden attacks of pain that come and go, and have a high fever 
• Trioxide of arsenic (Arsenicum album) – for individuals with a swollen abdomen, unquenchable thirst, extreme chills, and symptoms that worsen at night 
• Bushmaster snake (Lachesis) – for individuals with a hot abdomen and a painful stiffness radiating down to the thighs 

Prognosis and Complications

Complications from peritonitis can include the following:

• Sepsis – an infection throughout the blood and body that can potentially cause multiple organ failure 
• Abnormal clotting of the blood (generally due to significant spread of infection) 
• Formation of fibrous tissue in the peritoneum 
• Adult respiratory distress syndrome– a severe infection of the lungs
• Some forms of chronic peritonitis do not respond to treatment 

The prognosis for peritonitis depends primarily on the type of the condition. For example, the outlook for those with secondary peritonitis tends to be poor (10% to 40% mortality rate), especially among the elderly, individuals with compromised immune systems, and those who have had symptoms for longer than 48 hours before treatment. While the long-term outlook for individuals with primary peritonitis related to liver disease also tends to be poor, the prognosis for primary peritonitis among children is generally very good after treatment with antibiotics.

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