Crohn’s disease is a type of inflammatory bowel disease. It affects the digestive tract and causes diarrhea, abdominal pain, and weight loss.

The symptoms may appear suddenly, but they can also develop gradually and can get worse over time. They may vary according to the part of the digestive tract that Crohn’s affects and the severity of the disease.

Experts do not know why Crohn’s disease happens. It may result from an autoimmune reaction, in which the body’s immune system attacks healthy cells.

In this article, we examine the signs and symptoms of Crohn’s disease and explain how they can differ depending on which part of the gut they affect. We also look at diagnosis and when to see a doctor.

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Crohn’s disease is most likely to appear in people aged 15–30 years or 40–60 years. However, it can start at any age.

The symptoms can vary depending on which part of the intestine Crohn’s affects. It usually occurs in the large intestine (colon). This can lead to the following symptoms:

Common symptomsdiarrhea
unexplained weight loss
stomach pain or cramping
bloating
Other symptomsloss of appetite
anemia
fever
tiredness
eye pain or redness
tender, red bumps under the skin
nausea
joint pain
blood and mucus in the stool
Severe or advanced symptomsabscesses
fistulas

If Crohn’s affects the small intestine, a person may experience the following:

Common symptomsdiarrhea
malabsorption
weight loss
abdominal pain
low appetite
Severe or advanced symptomsfistulas leading to:
urinary tract infections
air bubbles in urine
feculent vaginal discharge

In children

In children, Crohn’s disease can lead to:

  • cramping
  • abdominal pain
  • regular episodes of watery diarrhea
  • fatigue
  • fever
  • nausea
  • loss of appetite, which can affect growth and weight gain
  • malnutrition due to a low calorie intake
  • nutritional deficiencies due to malabsorption
  • delays in puberty in some cases
  • bleeding in the digestive system
  • anemia, leading to pale skin, faintness, and other symptoms

Around 30% of children with Crohn’s disease develop perianal disease. They may have:

  • abscesses
  • fissures
  • skin tags
  • pain when using the bathroom

As the disease progresses, a child may experience:

  • obstruction of the large intestine, leading to constipation, cramping, and vomiting
  • lesions in or around the mouth, which affect 40% of children with the disease
  • painful, small, raised, red bumps on the skin, especially on the shins
  • burning or itching in the eyes due to inflammation
  • joint pain or arthritis

Other conditions and complications

Other signs and complications that commonly occur with Crohn’s disease include:

Symptoms worsen during a flare-up and improve in times of remission. Stress and certain foods may trigger or worsen symptoms.

People should visit a doctor if they experience any of the following symptoms:

  • diarrhea that lasts for 7 days or longer
  • frequent stomach pain, cramping, and discomfort
  • blood in the stool
  • unexplained weight loss

A doctor will start by asking about signs and symptoms. However, the most common symptoms of Crohn’s disease can also occur with other disorders.

For this reason, a person will likely undergo various tests to confirm whether their symptoms are due to Crohn’s disease.

The doctor may:

  • ask about pain and other symptoms
  • ask about personal and family medical history
  • carry out a physical examination

They may also recommend some of the following tests:

  • a rectal examination
  • CT scan or MRI scan of the abdominal area
  • X-rays to check for blockages
  • stool sample to check for an infection or other diseases
  • blood tests
  • colonoscopy

A colonoscopy involves inserting a thin, flexible tube into the digestive tract through the anus. The tube has a light and camera on it. It enables the doctor to see what is happening inside the gut.

People may often mistake the early signs and symptoms of Crohn’s disease for those of other conditions, such as:

It is best to visit a doctor if symptoms persist for more than 2 weeks. They can look for the cause of the problem and recommend suitable treatment.

There are five types of Crohn’s disease, which differ according to the part of the digestive tract that they affect. They also have slightly different symptoms, which helps doctors diagnose them correctly.

Below is a quick overview of each of the five types of Crohn’s disease and their symptoms. To learn more about these types, click here.

Ileocolitis

This is the most common type. It affects both the large intestine and the end of the small intestine.

Common symptoms are:

  • pain or cramping in the center or lower right region of the abdomen
  • diarrhea
  • sudden, unexplained weight loss

Ileitis

This type affects the ileum, the narrowest and final section of the small intestine.

Its symptoms resemble those of ileocolitis, but complications can arise. These include fistulas or abscesses in the lower right part of the abdomen.

A fistula in the gut is a passage that develops between the digestive tract and another part of the body.

Crohn’s colitis

Crohn’s colitis, also known as granulomatous colitis, only affects the large intestine, also known as the colon.

Common symptoms include:

  • ulcers, fistulas, and abscesses around the anus
  • joint pain
  • skin changes
  • diarrhea
  • bleeding from the rectum

Gastroduodenal Crohn’s disease

With gastrodudenal Crohn’s disease, severe inflammation occurs in the stomach and the first part of the small intestine.

Symptoms include:

  • loss of appetite
  • weight loss
  • nausea
  • vomiting

Jejunoileitis

This type affects the upper half of the small intestine, called the jejunum.

Symptoms include:

  • diarrhea
  • stomach cramping or discomfort after eating
  • fistulas in severe cases

Crohn’s disease and ulcerative colitis (UC) are both types of inflammatory bowel disease (IBD). Irritable bowel syndrome and celiac disease can also produce similar symptoms.

This table shows some of the similarities and differences between them.

Crohn’sUCIBSCeliac disease
AgeAny, but especially 15–30 years and also 50–70 yearsAny, but especially 15–30 years and 40–60 yearsAny, but especially in the youngAny, but especially 30s-40s
SexAnyAnyEspecially in femalesTwice as common in females
Area affectedColonAny part of the digestive tractColonSmall intestine
Common symptomsDiarrhea and bleedingPain, diarrhea, weight lossAbdominal pain and cramping relieved by defecation; bloating, diarrhea and constipationDiarrhea and other symptoms, depending on age at start
Risk factorsSmokingGenetic factorsPsychological stressHaving another condition, particularly an autoimmune disorder

Here, find out how Crohn’s compares with other digestive disorders.

There is no cure for Crohn’s disease, but people can make certain lifestyle changes and take medicines to relieve symptoms and manage the condition.

Depending on the type of Crohn’s disease, the severity of symptoms, and the person’s medical history, doctors may recommend one or more of the following treatment options:

  • steroids or other medicines to reduce inflammation
  • anti-diarrheal medication to treat mild diarrhea
  • sulfasalazine to manage mild symptoms
  • surgery to remove a part of the stomach or intestine
  • antibiotics to destroy any bacteria that may cause infection
  • draining any abscesses
  • biologic agents, such as anti-tumor necrosis factor (anti-TNF) drugs and anti-integrin agents

Biologic drugs can help manage and prevent flares by affecting the way the immune system works.

Examples of anti-TNF drugs include:

  • infliximab (Remicade)
  • adalimumab (Humira)
  • golimumab (Simponi)

Anti-integrin agents for Crohn’s include natalizumab (Tysabri) and vedolizumab (Entyvio).

Dietary tips

The National Institute of Diabetes and Digestive and Kidney Diseases suggests some dietary changes to help reduce the symptoms of Crohn’s disease. They include:

  • avoiding fizzy drinks
  • avoiding high-fiber foods, such as popcorn
  • drinking more liquid
  • eating small, frequent meals
  • keeping a food diary to help identify triggers

Other lifestyle measures

Apart from diet, the following lifestyle tips may help manage Crohn’s disease:

Prevention

As experts do not fully understand the cause of Crohn’s disease, they cannot recommend a way to prevent it. However, the following may help:

  • avoiding or quitting smoking
  • following a low-fat diet
  • discussing the risk with a doctor before using NSAIDs, birth control pills, and some antibiotics

How close are we to a cure for Crohn’s disease?

The early signs and symptoms of Crohn’s disease can resemble those of other conditions.

Anyone who notices new and persistent gastointestinal symptoms should seek medical help. Early treatment can help manage symptoms and prevent flares and complications.

Most people with Crohn’s disease will need life-long management. Maintaining contact with a medical team and following a treatment plan can help manage the symptoms and improve quality of life. Having support from others who understand the condition can also help.

IBD Healthline is a free app that you can download from the AppStore or Google Play. It can provide support for people with IBD, including Crohn’s disease.

Read the article in Spanish.