Diagnosis: Intestinal pain

It is better to refer to "intestinal pain" as abdominal pain, because a person can rarely tell that the pain originates exactly from the intestines. Although intestinal or abdominal pain can arise from the tissues of the abdominal wall that surrounds the abdominal cavity, the term abdominal pain is used to describe the pain originating from organs within the abdominal cavity.

What are the borders of the abdomen? Well, the abdomen is an anatomical area that bounds the lower margin of the ribs above, the pelvic bone below, and the flanks on each side. [1]

These organs include:

• Organs related to digestion — the stomach, the end of the esophagus, the small and large intestines, the liver, the gallbladder, and the pancreas.
• The abdominal aorta — a large blood vessel that runs straight down from the thorax into the inside of the abdomen.
• The appendix — an organ in the lower right abdomen that no longer has a function (and is, as such, an evolutionary remnant).
• The kidneys — two bean-shaped organs that lie deep within the abdominal cavity. [1]

However, the pain may originate from somewhere else like your chest or pelvic region. You may also have a generalized infection affecting many parts of your body, like the flu, candida or strep throat. 

“Referred” Pain 

In some rare cases, the pain felt in the abdomen isn’t related to any organ in the abdominal cavity. There is a theory that explains this conclusion. Abdominal pain has the unusual ability to travel along the deep nerve pathways and emerge at sites away from the source of the problem. For example, the lower lungs, the kidneys, and the uterus or ovaries can project pain into the abdomen. We call this type of pain "referred pain". Although the pain originates outside the abdomen, we attribute it to the abdominal area. [2]

Some examples of referred pain are [2]:

• The right shoulder can project into the diaphragm, gallbladder, and liver capsule
• The left shoulder can project into the diaphragm, spleen, the tail of the pancreas, stomach, splenic flexure, and pneumoperitoneum
• The right scapula can project into gall bladder, biliary tree
• Left scapula projects into spleen and tail of the pancreas