What are the guidelines for the diagnosis and management of all types of colitis, including ulcerative colitis (UC) and Crohn's colitis?

From the Guidelines

The management and diagnosis of colitis requires a systematic approach based on the specific type of inflammation, with the most recent guidelines from 2020 suggesting the use of biologic agents such as infliximab, adalimumab, golimumab, vedolizumab, tofacitinib, or ustekinumab for moderate to severe ulcerative colitis 1. Initial diagnosis typically involves a combination of clinical evaluation, laboratory tests (including complete blood count, inflammatory markers, and stool studies), endoscopy with biopsies, and imaging studies such as CT or MRI. For infectious colitis, stool cultures and specific pathogen testing are essential, with treatment involving targeted antibiotics like metronidazole for C. difficile (500mg three times daily for 10-14 days) or ciprofloxacin for bacterial pathogens (500mg twice daily for 5-7 days). Inflammatory bowel disease (IBD) colitis management begins with 5-aminosalicylates such as mesalamine (2.4-4.8g daily) for mild to moderate ulcerative colitis, with corticosteroids like prednisone (40-60mg daily with taper) for flares. Some key points to consider in the management of colitis include:

• The use of endoscopy with biopsies for diagnosis and excluding other causes of acute colitis, with flexible sigmoidoscopy being sufficient in most cases 1
• The importance of considering differentials at the time of diagnosis and when there is an incomplete response to treatment or flare, including infection, proximal constipation, Crohn's disease, co-existent irritable bowel syndrome, and rectal prolapse/solitary rectal ulcer 1
• The need for regular follow-up to monitor disease activity, medication efficacy, and potential complications, with treatment adjustments based on clinical response
• The recommendation for early specialist referral for severe or refractory cases to optimize outcomes and prevent disease progression Maintenance therapy often includes immunomodulators like azathioprine (2-2.5mg/kg/day) or biologics such as infliximab (5mg/kg at weeks 0,2, and 6, then every 8 weeks) 1. Microscopic colitis typically responds to budesonide (9mg daily for 8 weeks with taper). Ischemic colitis requires addressing underlying vascular issues and supportive care. For all types, supportive measures include hydration, electrolyte replacement, dietary modifications, and pain management. It is essential to prioritize the most recent and highest quality evidence, such as the 2020 guidelines from the AGA, to ensure the best possible outcomes for patients with colitis 1.

From the FDA Drug Label

The safety and efficacy of infliximab were assessed in 2 randomized, double-blind, placebo-controlled clinical studies in 728 patients with moderately to severely active ulcerative colitis (UC) Clinical response was defined as a decrease from baseline in the Mayo score by ≥30% and ≥3 points, accompanied by a decrease in the rectal bleeding subscore of ≥1 or a rectal bleeding subscore of 0 or 1 In both Study UC I and Study UC II, greater percentages of patients in both infliximab groups achieved clinical response, clinical remission and mucosal healing than in the placebo group. RENFLEXIS is indicated for reducing signs and symptoms, inducing and maintaining clinical remission and mucosal healing, and eliminating corticosteroid use in adult patients with moderately to severely active ulcerative colitis who have had an inadequate response to conventional therapy.

The guidelines for management and diagnosis of ulcerative colitis include:

• Clinical response defined as a decrease from baseline in the Mayo score by ≥30% and ≥3 points, accompanied by a decrease in the rectal bleeding subscore of ≥1 or a rectal bleeding subscore of 0 or 1
• Treatment with infliximab for reducing signs and symptoms, inducing and maintaining clinical remission and mucosal healing, and eliminating corticosteroid use in adult patients with moderately to severely active ulcerative colitis
• Dosing regimen of 5 mg/kg given as an intravenous induction regimen at 0,2 and 6 weeks followed by a maintenance regimen of 5 mg/kg every 8 weeks thereafter
• Monitoring for the development of signs and symptoms of infection during and after treatment with infliximab 2 2

The guidelines for management and diagnosis of other types of colitis are not directly addressed in the provided drug labels.

From the Research

Diagnosis of Colitis

• The diagnosis of colitis involves a combination of clinical evaluation, laboratory tests, and endoscopic examinations 3.
• Colonoscopy with biopsy is the test of choice for diagnosing ulcerative colitis and microscopic colitis 3.
• Diagnosing Crohn's disease typically requires ileocolonoscopy and may also require esophagogastroduodenoscopy 3.
• Multiplex polymerase chain reaction (PCR) followed by guided culture on PCR-positive pathogens can often confirm active infection in infectious colitis 4.

Management of Colitis

• The management of colitis depends on the type and severity of the disease 5, 6, 3, 7.
• Conventional therapies for ulcerative colitis and Crohn's disease include aminosalicylates, corticosteroids, thiopurines, methotrexate, and anti-tumor necrosis factor agents 5.
• Budesonide is considered first-line treatment for microscopic colitis given its favorable side effect profile and good efficacy 6.
• Biologic drugs targeting tumor necrosis factor alpha and other inflammatory drugs have revolutionized the care of inflammatory bowel disease 3.
• Surgery can be curative in ulcerative colitis, while in Crohn's disease, surgery is typically only used for complications or refractory disease 3.

Treatment Approaches

• A time-structured approach is required for the appropriate management of inflammatory bowel disease 5.
• Traditional step-up therapy has been partly replaced by potent drugs and top-down therapies, with an accelerated step-up approach being the most appropriate in the majority of patients 5.
• The treatment goal for microscopic colitis is to reduce the number of bowel movements and improve consistency 6.
• Antimicrobial therapy is often used to treat infectious colitis, and the choice of antibiotic depends on the causative pathogen 4.