Bloating, gas, diarrhea, and abdominal pain are symptoms that could apply to any number of gastrointestinal (GI) conditions. It’s also possible to have more than one problem with overlapping symptoms.

That’s why diagnosing GI disorders can be such a painstaking process. It may take a series of diagnostic tests to eliminate some diseases and find evidence of others.

While you’re probably eager for a quick diagnosis, it’s worth waiting for the correct one. Though the symptoms are similar, all GI disorders are different. The wrong diagnosis can lead to delayed or incorrect treatment. And without proper treatment, some GI disorders can have life-threatening complications.

You can help the process along by telling your doctor about all of your symptoms, personal medical history, and family medical history. Don’t leave anything out. Things like lack of appetite and weight loss are important clues.

Once you have a diagnosis, your doctor can explain all your treatment options so you can get on the path to feeling better. It can also be a good idea to get a second opinion if you think any of your diagnosis has been overlooked.

Keep reading to learn about some GI conditions with overlapping symptoms that can complicate diagnosis.

EPI is when your pancreas doesn’t produce the enzymes you need to break down food. EPI and a number of other GI disorders share symptoms such as:

  • abdominal discomfort
  • bloating, always feeling full
  • gas
  • diarrhea

When compared to the general population, you’re at higher risk of EPI if you have:

  • chronic pancreatitis
  • cystic fibrosis
  • diabetes
  • pancreatic cancer
  • pancreas resection procedure

It’s also possible to have EPI plus another GI condition such as:

  • inflammatory bowel disease (IBD)
  • celiac disease
  • irritable bowel syndrome (IBS)

Getting this diagnosis right is important. EPI interferes with the ability to absorb essential nutrients. Delayed diagnosis and treatment can lead to poor appetite and weight loss. Without treatment, EPI can also lead to malnutrition. Signs of malnutrition include:

  • fatigue
  • low mood
  • muscle weakness
  • weakened immune system, causing frequent illness or infection

There’s no one specific test to diagnose EPI. Diagnosis usually involves a series of tests, including a pancreatic function testing.

Crohn’s disease and ulcerative colitis are both chronic inflammatory bowel diseases. Together, they affect more than in the United States and several million around the world.

Some of the symptoms are:

  • abdominal pain
  • chronic diarrhea
  • fatigue
  • rectal bleeding, bloody stools
  • weight loss

Ulcerative colitis affects the inner layer of the large intestine and the rectum. It tends to impact more men than women.

Crohn’s disease involves the entire GI tract from the mouth to the anus and involves all layers of the intestinal wall. It affects more women than men.

The diagnostic process for IBD can be very challenging since symptoms of Crohn’s disease and ulcerative colitis are similar. Plus, they overlap with symptoms of other GI disorders. But getting to the correct diagnosis is crucial to choosing the right treatment and avoiding serious complications.

IBS affects about 10 to 15 percent of the population worldwide. If you have IBS, your body is very sensitive to gas in the system and your colon contracts too often. Symptoms can include:

  • abdominal pain, cramping, and discomfort
  • alternating diarrhea, constipation, and other changes to your bowel movements
  • gas and bloating
  • nausea

IBS is more common in women than men and usually starts in adults in their 20s and 30s.

Diagnosis is based mainly on symptoms. Your doctor may order a series of tests to rule out IBS and some other GI disorders, especially if you have:

  • additional symptoms such as bloody stools, fever, weight loss
  • abnormal lab tests or physical findings
  • family history of IBD or colorectal cancer

Diverticulosis is a condition in which tiny pockets form in weak spots in the lower large intestine. Diverticulosis is rare before age 30, but common after age 60. There usually aren’t any symptoms, so you're unlikely to know you have it.

A complication of diverticulosis is diverticulitis. This happens when bacteria gets trapped in the pockets, causing infection and swelling. Symptoms can include:

  • bleeding
  • chills, fever
  • cramping
  • tenderness in the lower abdomen
  • obstruction of the colon

Symptoms can be similar to those of IBS.

The correct diagnosis is important because if the intestinal wall tears, waste products can leak into the abdominal cavity. This can lead to painful abdominal cavity infection, abscesses, and intestinal blockages.

Ischemic colitis is when narrowed or blocked arteries reduce blood flow to the large intestine. As it deprives your digestive system of oxygen, you might have:

  • abdominal cramping, tenderness, or pain
  • diarrhea
  • nausea
  • rectal bleeding

Symptoms are similar to those of IBD, but abdominal pain tends to be on the left side. Ischemic colitis can happen at any age but is more likely after age 60.

Ischemic colitis can be treated with hydration and sometimes resolves on its own. In some cases, it can damage your colon, making corrective surgery necessary.

If you have undiagnosed GI problems, your specific symptoms and medical history will help your doctor determine the next steps. Some other GI conditions with overlapping symptoms include:

  • bacterial infection
  • celiac disease
  • colon polyps
  • endocrine disorders such as Addison’s disease or carcinoid tumors
  • food sensitivities and allergies
  • gastroesophageal reflux disease (GERD)
  • gastroparesis
  • pancreatitis
  • parasitic infection
  • stomach and colorectal cancers
  • ulcers
  • viral infection

If you’re experiencing GI symptoms like those listed above, make an appointment with your doctor. Be sure to go over all your symptoms and how long you’ve been having them. Be ready to talk about your medical history and any allergies you may have.

The details of your symptoms and their possible triggers are crucial information for your doctor to diagnose your condition and treat you properly.