The descending colon is a part of the large intestine. The colon’s left side is the one that descends. It is in charge of keeping the leftovers of digested food until they are eliminated through the rest of the colon and rectum.
The large intestine is involved in nutrient absorption. It also prepares the body’s waste products for removal.
The colon is the section of the large intestine that is the longest. Water and salt are absorbed, and liquid waste is solidified into stool. The ascending, transverse, descending, and sigmoid colons are the four primary parts.
Ulcerative colitis (UC), Crohn’s disease, and colorectal cancer are just a few of the disorders that can impact the function of this section of the digestive tract.
We’ll look at the structure of the descending colon, as well as its function and the disorders that can affect it, in this article.
What is it?
The colon is the largest and longest part of the large intestine, and it is divided into four sections:
- the sigmoid colon
- the ascending colon
- the descending colon
- the transverse colon
The big intestine is a component of the gastrointestinal tract that connects to the small intestine on one end and the anus on the other.
The descending colon connects the transverse colon to the sigmoid colon and is the third primary portion. It begins from the splenic flexure, or bend, and finishes at the sigmoid colon’s junction. It’s called a retroperitoneal organ because it’s located behind the peritoneum. The peritoneum is the tissue that covers most of the abdominal organs and borders the abdominal wall.
The descending colon measures 10–15 cm in length. It’s in the abdomen’s left lumbar area. This area is located in the middle of the abdomen to the left. In this area, the descending colon runs in front of and down the left kidney.
Function
The descending colon’s major function is to store hardened stool that will eventually empty into the rectum and be removed from the body.
The teniae coli, or smooth muscle bands, produce a series of pouches, or haustra, in all four sections of the colon. The colon appears segmented as a result of this.
The gastrocolic reflex is activated when the colon fills with digested food, causing peristalsis, which is a sequence of wave-like muscular contractions that assist move food along the digestive tract. Food can now pass from the descending colon to the rectum.
The colon’s overall function includes:
- forming and moving stool forward into the rectum for removal
- producing and absorbing vitamins
- absorbing water and electrolytes
Conditions
The function of the descending colon and the colon as a whole may be affected by certain disorders. They may have an effect on the colon’s ability to absorb nutrients and create stool.
The following are some of the most prevalent descending colon health issues:
Crohn’s disease
Another chronic inflammatory disease is Crohn’s disease. It’s an autoimmune condition that can affect any region of the digestive tract, including the colon, from the mouth to the anus.
The skin, joints, bones, eyes, kidneys, and liver are all affected, though the digestive system is the most common. Furthermore, it causes intestinal ulcers, which cause discomfort and pain.
Experts are unsure what causes Crohn’s disease, but they believe it is caused by an aberrant immunological response. Other factors, like as genetics and the environment, could also be at play.
Irritable bowel disease (IBD) includes both UC and Crohn’s disease.
Colonic perforation
A colonic or bowel perforation is a type of gastrointestinal perforation that occurs in the colon.
A cut, tear, or puncture in the colon’s wall can be caused by an injury, but it can also be caused by infection, obstruction, or inflammation.
A colonic perforation causes significant abdominal pain and often necessitates emergency surgery, which may include the removal of a portion of the intestines.
UC
UC is an inflammatory condition that lasts for a long time. It is caused by immune system abnormalities that cause inflammation in the colon.
Ulcers form in the lining of the colon lining as a result of UC. This might cause in stool pain and the urge to stool regularly.
Experts are unsure of the actual cause of UC, however it could be caused by a condition of variables, including:
- infections
- environmental factors
- immune reactions
Colorectal cancer
Cancer that begins in the colon or rectum is known as colorectal cancer. This happens when cancer cells in the colon start to grow out of control.
Colorectal cancers typically begin as polyps on the inner lining of the colon. However, not all polyps become cancerous, and the likelihood of a polyp becoming cancerous varies depending on the type of tumor present.
The size and location of tumors, whether the cancer is recurring, and a person’s overall health will all influence treatment. Among the possibilities are:
Diverticulitis
Diverticulitis is a condition in which small pouches or sacs called diverticula form and push outward through weak areas in the colon wall, causing inflammation.
These protrusions may not always be problematic, but when they get inflamed, they can cause symptoms like:
- pain in the abdomen
- diarrhea
- constipation
They can also cause problems including perforation and bleeding.
The following treatments may be used:
- using antibiotics
- in some cases, undergoing surgery
- increasing one’s dietary fiber intake
- taking pain relief medication
Tips for a healthy colon
People should eat a well-balanced diet, drink lots of water, and exercise regularly to maintain a healthy colon.
The American Cancer Society provides the following colon health recommendations to help minimize the risk of colorectal cancer:
- reducing consumption of red and processed meats
- reaching or maintaining a moderate body weight
- limiting or avoiding alcohol consumption
- having a diet that is rich in vegetables, fruit, and whole grains
- quitting smoking
- exercising
- increasing dietary fiber intake
Conclusion
The big intestine includes the descending colon. It joins the transverse and sigmoid colon and is used to hold stool before it is emptied into the rectum.
The colon as a whole is responsible for absorbing nutrients from the diet as well as producing and releasing wastes.
IBD, colonic perforation, and diverticulitis are just a few of the health problems that can affect colon function.
Making healthy lifestyle choices, such as eating a balanced diet, exercising regularly, and limiting or avoiding processed meats and alcohol, can help to preserve intestinal health.
Sources:
- https://training.seer.cancer.gov/colorectal/anatomy/
- https://www.ncbi.nlm.nih.gov/books/NBK507857/
- https://www.cancer.org/cancer/colon-rectal-cancer.html
- https://www.niddk.nih.gov/health-information/digestive-diseases
- https://www.ncbi.nlm.nih.gov/books/NBK537224/
- https://www.ncbi.nlm.nih.gov/books/NBK470577/
- https://www.medicalnewstoday.com/articles/descending-colon
- https://www.ncbi.nlm.nih.gov/books/NBK549888/
- https://www.crohnscolitisfoundation.org/what-is-crohns-disease/overview
- https://www.crohnscolitisfoundation.org/what-is-ulcerative-colitis/overview
- https://www.cancer.gov/publications/dictionaries/cancer-terms/def/retroperitoneal
- https://www.training.seer.cancer.gov/anatomy/digestive/regions/intestine.html
- https://www.cdc.gov/ibd/what-is-IBD.htm
