Enterocolitis is inflammation in both of your intestines at once. You might have enterocolitis if you have an especially severe reaction to common infections. This usually occurs in infants and the immunocompromised.


What is enterocolitis?

Enterocolitis is an inflammation that occurs throughout your intestines. It combines “enteritis,” inflammation of the small intestine, with “colitis,” inflammation of the large intestine.

Inflammation in either of your intestines is common, but when it occurs in both, it tends to be more severe. It also tends to affect those with more vulnerable immune systems, especially infants.

How does enterocolitis affect my body?

Inflammation in your intestines typically affects the inner lining (mucosa). It causes swelling, tenderness and changes to the way your intestines secrete and absorb. This affects your digestion and your poop.

Inflammation is a response from your immune system when something is infecting or injuring your body. Your immune system may also cause general symptoms of illness along with local inflammation.


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Symptoms and Causes

Enterocolitis symptoms include abdominal pain and nausea.
Enterocolitis feels like a stomach bug that extends throughout your intestines.

What are the symptoms of enterocolitis?

Typical symptoms of enterocolitis include:

How long does enterocolitis last?

It depends on the cause. Infections, the most common causes, are usually temporary. Your immune system can often defeat them on its own, though sometimes, you might need medication.

Some of the less common causes, such as autoimmune diseases, can be long-lasting. Chronic diseases aren’t curable, but healthcare providers can treat the inflammation separately with medication.

What causes enterocolitis?

In theory, any of the normal causes of enteritis or colitis could also cause enterocolitis in both intestines. But this would indicate an unusually severe reaction and possibly a more vulnerable immune system.

Common causes of enteritis and colitis include viral infections, such as the stomach flu, parasite infections, like giardiasis, and bacterial infections, such as food poisoning.

Overuse of certain substances, such as alcohol, cocaine and over-the-counter drugs can cause bowel inflammation. Other causes include chronic bowel diseases such as celiac disease and Crohn’s disease.

You’re more likely to get enterocolitis in both intestines if your immune system is not at full strength. Infants and children are more commonly affected, as well as those with chronic illnesses such as HIV.


What are the specific types of enterocolitis?

Healthcare providers have given names to certain types of enterocolitis that come from certain causes. These causes represent trickier infections and diseases that are more likely to affect both intestines.

Specific types include:

Necrotizing enterocolitis

Necrotizing enterocolitis (NEC) affects ill and premature infants, who are already immunocompromised. These babies’ intestines react severely when exposed to normal bacteria through feeding. Inflammation and swelling are so severe that the blood supply to their intestinal lining is cut off, causing tissue death. This is what “necrotizing” means.

Doctors aren’t sure what the original cause of inflammation is in NEC. It might be due to the diminished blood supply to these babies’ intestines, or it might be due to bacterial infections that find it easier to take hold when the blood supply is low. Both factors seem to contribute.

Pseudomembranous enterocolitis

Pseudomembranous enterocolitis is also known as antibiotic-associated enterocolitis. It’s caused by a bacterial infection, but also, ironically, by antibiotics. This particular bacterium — Clostridium difficile (C. diff) tends to infect people who’ve recently taken antibiotics to treat a different infection. Many common antibiotics don’t kill C. diff, but they do kill the other bacteria in your gut that would kill C. diff. This allows C. diff to easily grow out of control.

As it grows, the bacterium releases toxins into your intestinal lining. Some people have a particularly severe reaction to those toxins, which can lead to enterocolitis. This infection is common in hospitals and nursing homes, due to the combination of compromised immune systems, antibiotics use and C. diff’s ability to live for a long time on surfaces.

Hemorrhagic enterocolitis

E. coli infections can cause hemorrhagic enterocolitis. E. coli is a bacterium that commonly and harmlessly lives in our intestines. The danger comes from a particular strain known as enterohemorrhagic E. coli (EHEC), also known as Shiga toxin-producing E. coli (STEC). This strain produces toxins (called Shiga toxins) that adhere to your intestinal lining, causing inflammation and bleeding (hemorrhage.)

“Enterohemorrhagic” means bleeding in your small intestine. Those who react more severely to Shiga toxins may have enterocolitis and bleeding in both intestines. This will cause bloody diarrhea (dysentery.) Hemorrhagic enterocolitis most commonly affects the very young and old.

Food protein-induced enterocolitis

Food protein-induced enterocolitis syndrome (FPIES) is a food allergy reaction that mostly affects children under two. It causes an inflammatory immune response in their intestinal lining. FPIES is a non-IgE mediated allergy, which makes it different from other allergies you may be familiar with.

Most allergies cause your immune system to produce specific antibodies to the allergen, called IgE antibodies. These antibodies cause an immediate reaction that you may experience as symptoms in your nose, throat, lungs or skin. Non-IgE mediated allergies don’t produce IgE antibodies. Instead, they cause a delayed reaction in your intestines alone, leading to symptoms of enterocolitis.

Hirschsprung-associated enterocolitis

Hirschsprung-associated enterocolitis is a common and dangerous complication of Hirschprung disease, a birth defect that affects the large intestine. Babies with Hirschprung disease are missing certain cells in the lining of their large intestines, usually in one segment. These cells are involved in the muscle contractions that move poop through the large intestine (peristalsis.)

In the segment where the cells are missing, poop doesn’t continue to move through and builds up, causing a blockage. This blockage creates a breeding ground for bacteria to overgrow. Bacterial overgrowth can spread to both intestines and eventually degrades the intestinal lining, allowing the bacteria to infiltrate the lining. All of these factors may contribute to causing enterocolitis.

Neutropenic enterocolitis

Neutropenic enterocolitis affects people experiencing neutropenia, lower-than-normal levels of white blood cells called neutrophils. These are the cells that would normally help protect you from infections. People who have neutropenia are prone to more serious infections that may lead to enterocolitis.

Most people with neutropenic enterocolitis have undergone chemotherapy for blood cancers such as leukemia and lymphoma. These conditions cause neutropenia, and chemotherapy itself contributes to weakening the intestinal mucosa. But it can also occur in people with neutropenia due to other conditions, such as HIV/AIDS and autoimmune diseases.

Diagnosis and Tests

How is enterocolitis diagnosed?

The signs and symptoms of enteritis, colitis and enterocolitis are similar. A healthcare provider might not know right away which parts of your intestines are affected, but they will suspect inflammation based on your physical signs and symptoms. After that, their job will be to identify the cause. This will allow them to diagnose the specific type of enterocolitis.

Healthcare providers use blood tests, poop tests and imaging tests to look for information about what’s causing your condition. Imaging tests, such as an abdominal ultrasound or CT scan can show evidence of inflammation and possible complications in your bowels. Blood tests and poop tests can help identify specific infections or diseases that may be involved.


Management and Treatment

How do healthcare providers treat enterocolitis?

Treatment will be targeted to the cause. Acute treatments might include:

In severe cases, some people need:

  • Drainage of fluids, gas or solids from your intestines or peritoneal cavity.
  • Surgical interventions to repair a hole, relieve a blockage or remove dead tissue.
  • A temporary colostomy or ileostomy to redirect food from the bowels while they heal.
  • IV nutrition.

Outlook / Prognosis

Will my baby recover from enterocolitis?

Enterocolitis that affects infants, including necrotizing enterocolitis and Hirschsprung-associated enterocolitis, can be life-threatening. However, with timely diagnosis and treatment, most infants recover. Some may continue to have recurring infections or other long-term complications.

What are the possible complications of severe enterocolitis?

Complications can include:

  • Stricture and obstruction. Chronic inflammation and wounding of the intestinal lining can lead to scarring of the tissues. Scar tissue can cause the intestines to narrow (stricture,) which can obstruct the passage of solids through the intestines.
  • Ischemia and necrosis. Loss of blood supply to the tissues lining the intestines can cause tissue death. Dead tissue must be removed to preserve the rest.
  • Short bowel syndrome. Children who need to have part of their intestines removed due to complications may have trouble absorbing enough nutrients from their food (malabsorption.) This can lead to malnutrition, failure to thrive and growth and development delays.
  • Cholestasis. Children who are unable to feed normally through their digestive system during enterocolitis may have a build-up of bile in their bile ducts. When bile doesn’t flow normally to the intestines to help with digestion, it becomes static, which can lead to sedimentation and gallstones. Bile can also back up in the gallbladder and liver, causing inflammation.
  • Intestinal perforation. Necrosis, severe ulceration or bacterial infiltration can degrade the intestinal lining until it breaks or tears. This allows intestinal bacteria to escape.
  • Septicemia, sepsis and shock. Infection that escapes your intestines into your peritoneal cavity (peritonitis) can spread to your bloodstream next (septicemia.) This can lead to whole-body inflammation and blood clotting (sepsis.) Sepsis is an emergency. In the most severe cases, it can lead to septic shock, which involves multiple organ failure and a high fatality rate.

A note from Cleveland Clinic

Inflammation in the intestines is common, especially as a response to infection. But when it affects both your small and large intestines, it tends to be more serious. Enterocolitis more often affects people with weaker-than-normal immune systems. This can make it scarier than normal for those affected and their loved ones. But with careful attention and quick response, healthcare providers and treat it before complications arise. If you or a loved one is immunocompromised, stay alert to the risk of enterocolitis.

Medically Reviewed

Last reviewed on 01/19/2023.

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