Colitis Cystica Profunda - Causes, Symptoms, Diagnosis, and Treatment

What Is CCP?

It is an inflammatory condition characterized by the presence of mucus-filled cysts in the muscular mucosa (outermost layer of the mucosa) of the colon; although it may diffusely involve the entire colon, this disease primarily affects the pelvic colon and the rectum.

Mucus-filled cyst forms due to cystic dilation of the mucus glands in the colon; based on the location, these cysts are of two types-

1) Colitis Cystic Superficialis (CCS)- In this type, the cysts are minute and are diffusely distributed throughout the entire colon.

2) Colitis Cystica Profunda (CCP)- Here, the cysts are submucosal in nature and are confined to the rectum and the pelvic colon. They are large in size compared to the lesions seen in the CCS; some of them are as large as two centimeters in diameter. There are three types of CCP-

• Diffuse CCP- This form is frequently associated with inflammatory bowel disease (IBD); the lesions are observed throughout the colon and macroscopically appear as pedunculated polypoid lesions that are evenly ulcerated.
• Segmental CCP- It is characterized by the presence of polypoid lesions, typically in the rectosigmoid tract.
• Localized CCP- The lesion is situated along the anterior wall of the rectum, usually 5 cm to 12 cm from the anal orifice.

Common symptoms pertaining to CCP include rectal bleeding, mucus discharge, altered bowel habits, and long-standing constipation. The cause of CCP is unclear; however, it is associated with rectal prolapse (a condition where part of the large intestine slips out of the anus) in 50 % of the cases.

The endoscopic appearances of CCP are not unique, leading to a missed diagnosis of polyp or malignancy. Treatments of CCP include re-education of bowel habits to avoid straining, administration of fiber and laxatives, and biofeedback.

What Causes CCP?

The exact cause of CCP is unknown, but it’s histopathological (pathological changes in the tissue) features bear a close resemblance to those of solitary rectal ulcer syndrome (SRUS), leading to the belief that the causes responsible for the latter are also responsible for CCP. Some of the most accepted theories for CCP and SRUS are-

• Straining: Lengthened straining during bowel movements in a patient who suffers from constipation may result in direct trauma to the mucosa.

• Self-Induced Trauma: Self-instrumentation can occur when individuals try to remove impacted stools by rectal digitization and injure the mucosa in the process.

• Paradoxical Contraction of Puborectalis Muscle: Uncoordinated muscle contraction in the puborectalis muscle has been indicated to be associated with increased intrarectal pressure resulting in ischemia, ulceration, and cyst formation.

• Rectal Prolapse and Intussusception: Intussusception is where one part of the intestine slides into another. Rectal intussusception can lead to localized vascular trauma and consequently the onset of SRUS and CCP.

What Are the Symptoms of CCP?

The symptoms of CCP are nonspecific and often resemble those of IBD; some of them are-

• Rectal pain.

• Bleeding.

• Pain.

• Tenesmus (feeling like pooping even though the bowels are empty).

• Mucus in the stool.

• Chronic and severe constipation.

• Lengthened straining on defecation.

• Pelvic discomfort.

• Sense of incomplete evacuation.

Nearly 25 % of the patients are asymptomatic, but when the symptoms do occur, the most common one is bleeding (hemorrhage); the amount of hemorrhage varies from patient to patient, and at times it can be a little too severe, creating a need for blood transfusion.

How Is CCP Diagnosed?

CCP is a well-known condition but is often misdiagnosed due to its rare occurrence. The clinician should keep in mind that not all CCP lesions are cystic in appearance; some of them show areas of atrophy with superficial ulceration.

The diagnosis of CCP can be performed by a combination of symptomatology, endoscopy, sigmoidoscopy, and histology. Some of these are described below-

1. Flexible Sigmoidoscopy - It is a method in which a sigmoidoscope is inserted into the rectum to examine the rectum and part of the colon. It is used to determine the unknown cause of mucosal lesions, rectal ulcers, IBD, etc.

2. Transrectal and Endoanal Ultrasonography - An imaging technique that can describe a series of changes like thickened muscularis propria, thickened internal and external anal sphincter, etc.

3. Defecography - It is a type of radiological imaging in which different stages of defecation can be visualized by a fluoroscope.

4. Magnetic Resonance (MR) Defecography - This method can show the cause of constipation and other problems, such as lower limb prolapse.

5. Barium Enema - It is a type of X-ray imaging method that can be used for the examination of muscle function, coordination, and prolapse.

Although the above-mentioned investigations support the benign nature of CCP, only adequate biopsy offers a definitive diagnosis; the characteristic histological features of CCP are:

• Thickening of the mucosal layer along with crypt distortion.

• Fibromuscular distortion in the lamina propria has been known to be the cornerstone for the diagnosis of CCP.

• The extension of the muscle fibers in an upward direction between the cryptans (deep pits in the small intestinal mucosa).

• Glandular crypt abnormalities.

• Surface ulceration.

• Mucus cell proliferation, hyperplastic, and serrated mucosa.

• Mild inflammation.

How Is the CCP Treated?

Treatment of CCP is based on its symptoms; this includes-

• Conservative Treatment- This is preferred in patients who are mildly symptomatic. Treatment comprises a fiber diet, bulk laxatives, training for straining prevention, and anal digitation.

• Biofeedback- It includes a variety of behavioral changes that are effective in reducing excessive straining with defecation through correction of the abdominal pelvic floor and stopping the use of suppositories and laxatives.

This is the choice of treatment for patients in whom the conservative treatment is no longer effective and in cases where there is a high degree of intussusception in the rectum and fibrosis or external prolapse.

• Topical Therapy- This includes Sucralfate enema, corticosteroids, and Sulfasalazine; however, the long-term effectiveness of these medications is yet to be determined.

• Surgery- It is preferred in patients who suffer from rectal mucosal prolapse and are resistant to conservative management and biofeedback treatment. Some preferred surgical approaches are excision, diversion, perineal proctectomy (removal of part of the rectum), etc.

Conclusion:

CCP is a misleading condition that mimics clinical features of IBS, lipoma, sarcoma, colorectal adenocarcinoma, etc. Diagnosis should be made by analyzing the outcome of symptoms, sigmoidoscopy, and histology. Treatment should involve implementing a conservative approach and biofeedback as the first strategy, failure of which surgery should be considered.