Pseudomembranous Colitis Diagnosis and Treatment

What is pseudomembranous colitis?

Pseudomembranous colitis (PMC) is an inflammation of the colon and a severe form of colitis, often associated with an overgrowth of the bacteria Clostridioides difficile (C. difficile - formerly Clostridium difficile). C.difficile is normally present in about 5% of the population without causing any infection. But when for any reason when antibiotics are used or when the immune system is compromised, Clostridioides difficile multiply to produce toxins that cause inflammation of the gut and diarrhoea.¹

The term pseudomembrane is used to describe the formation of yellow-white plaques on the mucous membrane lining of the colon. When the disease causes damage to the epithelium surface and necrosis (death) of cells the immune system sends white blood cells to the site of necrosis. The dead cells combined with the white blood cells (neutrophils) form the pseudomembranes. Pseudomembranes can be up to two centimetres in diameter, scattered among areas of normal mucosa; however, pseudomembranes that cover the entirety of the mucosa can be seen in severe forms of the disease.²

Symptoms of pseudomembranous colitis

The symptoms of PMC may include the following:

• Watery diarrhea
• Stomach cramps
• Fever
• Nausea and sometimes vomiting
• Blood or pus in the stool

Causes of pseudomembranous colitis

The bacteria in our colon are kept in a natural healthy balance unless external factors like antibiotics or other medications disturb this balance. Pseudomembranous colitis occurs when certain bacteria, mostly Clostridioides difficile outgrows the bacteria that maintain the healthy balance. C.difficile then produces toxins that damage the colon. Any antibiotic can cause PMC but certain antibiotics are commonly associated with pseudomembranous colitis like fluoroquinolones, penicillins, clindamycin and cephalosporins. Chemotherapy drugs can disturb the balance in colon bacteria and cause PMC. Certain conditions like ulcerative colitis and Crohn’s disease can put you at risk of pseudomembranous colitis. C.difficile can also be transmitted through healthcare professionals to patients due to the high resistance of C. difficile spores to disinfectants. Recently PMC has been reported in people who had no healthcare contact and no recent history of antibiotics use, this is called community-acquired C. difficile.³ 

Risk factors

The chance of developing pseudomembranous colitis may increase if you are:

• Taking antibiotics
• Staying in hospital
• Staying in a nursing home
• Over the age of 65 years old
• Have a condition that weakens the immune system
• Under chemotherapy treatment for cancer
• Have a colon disease like inflammatory bowel disease
• Had a C. diff infection in the past

Complications of pseudomembranous colitis

In severe cases, pseudomembranous colitis can lead to serious complications and sometimes they can even be life-threatening. Possible complications include the following:⁴

• Dehydration and electrolyte loss: Severe pseudomembranous colitis causes severe watery diarrhoea 5 to 10 times/day. This can cause severe dehydration leading to serious complications like low blood pressure and kidney failure
• Fluid leakage: The severely infected and damaged colon lining can leak fluids into the abdominal cavity causing ascites ( when there is too much fluid in the abdominal cavity)
• Toxic megacolon: Rarely in severe cases, swelling of the colon may occur. In this case, the colon can lose movement and function and will be unable to get rid of gas and stool. If left untreated, the colon will continue to dilate and can rupture, spreading infection to the rest of the abdominal cavity (peritonitis)
• Gastrointestinal perforation: In addition to megacolon, tearing of the colon wall can occur due to ulcer or extensive necrosis (tissue death), the perforated colon can leak bacteria to the abdomen causing peritonitis, or the bloodstream causing septicaemia and death
• Death: If left untreated C. difficile can be fatal and causing death

Diagnosis

Besides the clinical presentation and medical history, several tests and procedures can be carried out to reach a final diagnosis of PMC:⁵

• Stool sample: Diagnosis of PMC focuses on the detection of C. difficile and its toxins in stool samples, the tests should be performed on diarrheal stool samples only, as stool samples from asymptomatic patients are clinically not useful
• Full Blood Count (FBC): White blood cell count is very high
• Sigmoidoscopy or colonoscopy: Not routinely used but can be used to examine the colon for pseudomembranes and swelling
• Imaging tests: X-rays and CT scans can be useful in severe cases to detect complications like colon perforation or megacolon

Treatment of pseudomembranous colitis

Treatment strategies for PMC may vary depending on the case and the cause of the infection but mostly include the following:³

• Stopping the antibiotics that are causing the symptoms, sometimes symptoms resolve completely after discontinuing antibiotics
• Start antibiotics that are effective against C. difficile and that allow typical bacteria to grow back to restore the balance
• The antibiotics used are: metronidazole, vancomycin and fidaxomicin
• Some cases need supportive treatment like IV fluids and IV nutrition
• Fecal microbial transplantation (FMT): In severe cases and cases of recurrence, stool transplant from a healthy donor is given to restore the balance of bacteria in the colon, this can be used alone or in combination with antibiotics for treatment
• In severely complicated cases, surgery may be required to treat organ failure or to remove a part of the colon (colectomy)

Prevention

The most important and effective way to prevent pseudomembranous colitis is to stop the spread of C. difficile by following proper infection control measures. Healthcare providers in hospitals and nursing homes should take special precautions to prevent C. difficile infection.

• Isolation of patients who are infected with C. difficile in their own rooms
• Wasing hands with soap and water
• Use of disinfectants that contain chlorine. C.difficile is resistant to many disinfectants t except high concentration of chlorine-based products. Hence, they can be used to disinfect all surfaces in contact with infected people
• Use antibiotics only when necessary and consult with your healthcare provider first

FAQ’s

Is it okay to be around someone with C. difficile?

C.difficile is contagious, but most healthy adults who come in contact with infected patients don’t get infected.

Can pseudomembranous colitis be cured?

Yes, in most cases treatment resolves the symptoms quickly, but some cases may need more treatment options, particularly cases of recurrence and complications.

What does C. difficile diarrhoea smell like?

Most people who suffer an infection with C. difficile describe the smell of diarrhoea as strong and oddly sweet.

What are the worst antibiotics that cause C. difficile?

The most common antibiotics associated with C. difficile infection are piperacillin/tazobactam, meropenem, vancomycin, ciprofloxacin, ceftriaxone, and levofloxacin.⁶

Summary

Pseudomembranous colitis is an inflammation of the colon often associated with C. difficile infection. The diagnosis of pseudomembranous colitis relies on medical history, clinical evaluation, stool tests, and endoscopic examination. Early diagnosis is crucial for initiating appropriate management, which typically includes discontinuing the causative antibiotic, administering targeted antibiotics against C. difficile and providing supportive care. Additionally, faecal microbiota transplantation may offer promising results, particularly in cases of recurrence or complicated disease. Prevention strategies need to focus on education and awareness about prescribing antibiotics and their use, infection control measures and heightened awareness among healthcare providers. By implementing comprehensive approaches to diagnosis, treatment and prevention, the burden of pseudomembranous colitis can be reduced, leading to improved patient outcomes and a lower incidence of this challenging condition.