Does colitis require antibiotics in the absence of fever or leukocytosis (elevated white blood cell count)?

From the Guidelines

Colitis does not always require antibiotics, especially if there is no fever or elevated white blood cell count, as the most recent and highest quality study suggests that select patients with acute uncomplicated left-sided colonic diverticulitis can be initially managed without antibiotics 1. The need for antibiotics depends on the specific type and cause of colitis. For inflammatory bowel diseases like ulcerative colitis or Crohn's disease, treatment typically focuses on anti-inflammatory medications such as mesalamine, corticosteroids like prednisone, or immunomodulators like azathioprine. Antibiotics are primarily indicated for infectious colitis caused by specific bacteria like Clostridioides difficile, for which metronidazole or vancomycin would be prescribed, as recommended by the European Society of Clinical Microbiology and Infectious Diseases 1. Without fever or elevated white blood cell count, which are signs of infection or severe inflammation, the focus should be on identifying the underlying cause through stool tests, colonoscopy, or imaging studies before determining appropriate treatment. Some key points to consider in the management of colitis include:

• The use of abdominal CT imaging for diagnostic uncertainty in patients with suspected acute left-sided colonic diverticulitis, as recommended by the American College of Physicians 1.
• The management of most patients with acute uncomplicated left-sided colonic diverticulitis in an outpatient setting, with low-certainty evidence showing no differences in diverticulitis-related complications or quality of life between outpatient and inpatient management 1.
• The potential harms of antibiotic use, including increased costs, potential for antibiotic resistance, and side effects, which should be weighed against the benefits of treatment 1. Symptomatic relief can be achieved with hydration, dietary modifications, and over-the-counter antidiarrheals like loperamide for mild cases. However, persistent or worsening symptoms, bloody diarrhea, severe abdominal pain, or signs of dehydration warrant prompt medical evaluation regardless of fever status. It is essential to consider the individual patient's circumstances, such as the availability of adequate home care, and to err on the side of caution when managing patients with suspected complicated diverticulitis or those with predictors of progression to complicated disease.

From the Research

Colitis Treatment

• The use of antibiotics in treating colitis depends on the presence of a bacterial infection, such as Clostridioides difficile (C. difficile) 2, 3, 4, 5, 6.
• In patients with inflammatory bowel disease (IBD), C. difficile infection can complicate the course of the disease, and the presentation may not be typical 2.
• Oral vancomycin or fidaxomicin are the preferred agents for non-fulminant C. difficile infection, while oral metronidazole is no longer recommended as first-line therapy 2.
• For patients with severe C. difficile colitis, intracolonic vancomycin enema protocol may be effective in achieving complete resolution without surgery 6.
• The decision to use antibiotics in treating colitis should be based on the severity of the disease, the presence of bacterial infection, and the patient's overall health status 3, 4, 5.

Antibiotic Use in Colitis

• Antibiotics may not be necessary for all cases of colitis, especially if there is no evidence of bacterial infection 5.
• However, in patients with IBD, antibiotics such as vancomycin may be necessary to treat C. difficile infection, even in the absence of fever or high white count 2, 3, 4.
• The use of antibiotics should be judicious and based on the clinical presentation and laboratory results 5.

Treatment Outcomes

• Studies have shown that patients with ulcerative colitis and non-severe C. difficile infection have fewer readmissions and shorter lengths of stay when treated with a vancomycin-containing regimen compared to those treated with metronidazole alone 3.
• Long-duration oral vancomycin therapy has been associated with lower rates of C. difficile recurrence compared to short-duration therapy 4.
• Intracolonic vancomycin enema protocol has been shown to be effective in achieving complete resolution without surgery in patients with severe C. difficile colitis 6.