Colitis

Differential diagnosis of colitis syndrome

Due to the absence of strictly specific early signs, ulcerative colitis and Crohn's disease (CD) of the colon require the exclusion of a wide range of pathologies. First of all, it is necessary to differentiate IBD from infectious and parasitic infestations. These include acute intestinal infections (shigellosis, salmonellosis, escherichiosis), as well as campylobacteriosis, yersiniosis, amebiasis, and helminthiases (specifically, trichuriasis). Special attention should be paid to intestinal tuberculosis and Clostridioides difficile-associated lesions, which may manifest as antibiotic-associated diarrhea or pseudomembranous colitis.

The second major group comprises non-infectious and surgical pathology. The differential diagnosis includes:

• Irritable bowel syndrome (IBS) is a classic diagnosis of exclusion, in which pain is clearly associated with changes in stool consistency or frequency of defecation.
• Neoplasms of the colon.
• Diverticulitis and mesenteric thrombosis.
• Microscopic colitis, which is subdivided into collagenous and lymphocytic colitis.
• Radiation proctitis.

In addition, IBD must be differentiated from rheumatological manifestations and systemic vasculitides. Severe gastrointestinal involvement in systemic diseases can mimic a severe form of Crohn's disease. It is also important to perform a differential diagnosis between IBD and the articular form of juvenile idiopathic arthritis.

Features of infectious colitis

When conducting differential diagnosis with infectious lesions, it is important to consider the clinical features of shigellosis (dysentery). This disease is characterized by specific local manifestations: sphincteritis and laxity of the anus. The stool has a pathognomonic appearance — it is scanty, liquid, and contains turbid mucus and streaks of blood, which in clinical practice is described as the "rectal spit" sign.

The clinical presentation of dysentery varies significantly depending on the patient's age and the causative agent:

1. Infants under 1 year: The dyspeptic form predominates. The disease begins gradually, accompanied by moderate fever. The distal colitis syndrome is mild, and the severity of the child's condition is determined not so much by local changes as by systemic disorders — hemodynamic instability, water-electrolyte, and protein metabolism disturbances.
2. Children over 1 year: There is a synchronous development of intoxication and local syndromes.
3. Sonne dysentery: Characterized by a milder course. Vomiting usually lasts about a day, fever persists for 1–2 days, diarrhea lasts less than one week, and manifestations of hemocolitis resolve within 1–3 days.
4. Flexner dysentery: Distinguished by a more severe and prolonged course with a pronounced distal colitis syndrome. This form carries a significantly higher risk of intestinal bleeding.

Morphological differentiation and principles of therapy

In cases of a perianal fistula, the histological picture of Crohn's disease requires differentiation from other specific processes. When ruling out tuberculosis, it is important to remember that CD is not characterized by the presence of caseous necrosis and acid-fast bacilli. If differential diagnosis with actinomycosis is performed, the morphological marker of the latter will be granulomas with signs of central suppuration.

Basic pharmacotherapy for inflammatory bowel disease includes prescribing glucocorticosteroids (for example, systemic prednisolone is used). The most crucial aspect of targeted therapy for Crohn's disease is the use of topical glucocorticosteroids — budesonide is considered the drug of choice, provided the inflammatory process is strictly localized in the ileocecal region.

As additional means of drug control, the following are used:

• Immunosuppressants (methotrexate, azathioprine).
• Combination drugs combining sulfonamides and salicylic acid.

Any medical treatment must necessarily be combined with a sparing regimen and diet therapy. Depending on the patient's condition, either a standard or high-protein diet is prescribed.

Class and exam questions

What else to study on this topic

• Complications of Crohn's disease
• Histological picture of inflammatory bowel disease
• Precancerous diseases of the colon
• Unclassified colitis

Other topics in the "Additional Topics" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.