Inflammatory bowel disease (IBD) is characterized by a chronic and recurrent inflammation of the intestinal wall with no specific etiology. Within IBD, we find two major pathologies: ulcerative colitis (UC) and Crohn’s disease (CD). While ulcerative colitis only affects the mucous of the colon wall, Crohn’s disease affects all the tissues of the intestinal wall and various digestive tract sections. It manifests intermittently throughout the life of the individual. The most accepted causal theory today is multifactorial, meaning that Crohn’s disease is a consequence of genetic, environmental, microbiological and immunological factors.
Some symptoms of Crohn’s disease are diarrhea (usually with blood), abdominal pain, presence of abdominal masses, sudden weight loss, fatigue, fecal tenesmus and fever.
CD can lead to complications such as abscesses, fistulas, intestinal obstruction, stenosis, perianal disease and toxic megacolon. In addition, this condition has been linked to a greater predisposition to colon cancer, although studies have not been conclusive due to a lack of knowledge about the origin of the disease.
Some other manifestations that patients may present are:
Uveitis and sacroiliitis
The diagnosis of inflammatory bowel disease is made through clinical, laboratory and histological data. Also, endoscopic and radiological tests are performed. It is necessary to always rule out celiac disease and intestinal infections since both pathologies may be causing the mucous inflammation. Oftentimes, the lack of an effective test for its detection leads to a significant delay in diagnosis and treatment.
Endoscopy is used for initial and differential diagnosis to determine the degree of severity of the lesions as well as the presence or absence of neoplasms in order to assess the response of treatment. An ileo-colonoscopy is the test of choice on the initial evaluation of Crohn’s disease.
Several radiological studies are carried out, including barium studies, ultrasounds, CT and magnetic resonance. Radiological studies help us detect edema, ulcers, stenosis, fistulas and extra intestinal affectations.
Biopsy in CD is a very important analysis for the differential diagnosis with other possible pathologies. The main characteristics of Crohn’s disease are:
Thickening of the intestinal wall
Presence of granulomas
Appearance of lymphocytes and plasma cells
Irregularity of the intestinal crypts
A calprotectin (calprotectin is a protein) test is useful to determine if there is intestinal inflammation or not by detecting the presence of this protein in feces. In addition, a general analysis will be performed to evaluate the patient’s condition.
Crohn’s disease is distinguished according to the age of the patient at diagnosis, the location of the pathology and the type of behavior:
Age at Diagnosis:
A1: Less than 16 years old.
A2: From 16 to 40 years old.
A3: Over 40 years old.
L3: Ileum and colon.
L4: If there is involvement of the upper digestive tract.
B1: Inflammatory type.
B2: Structuring type.
B3: Penetrating type.
P: If there is perianal involvement.
The general well-being of the patient, abdominal pain, the number of liquid stools per day and the presence of abdominal masses are all evaluated. The total score of the index may indicate if the disease is in remission, moderately active or markedly active, which will establish the severity and treatment of Crohn’s disease.