To diagnosis IBD a very through history and examination is needed. To differentiate between the two conditions, more extensive tests and imaging is required. CD can be diagnosed by x-ray, UC by a sigmoidoscopy or colonoscopy. For both conditions it is important to rule out other conditions such as infections.
Although ulcerative colitis and Crohn’s disease appear to be two distinct conditions, the same pharmacologic agents are used to treat both. Strong therapies are used, including 5-aminosalicylic acid derivatives, corticosteroids, agents such as mercaptopurine or azathioprine, methotrexate, and infliximab.
5-Aminosalicylic Acid (5-ASA) is a topically active agent that has a variety of anti-inflammatory effects. It is used in the active treatment of ulcerative colitis and Crohn’s disease and during disease inactivity to maintain remission. Commonly used formulations of 5-ASA are sulfasalazine, mesalamine, and azo compounds. Sulfasalazine may cause side effects in 15–30% of patients. Dose-related side effects include nausea, headaches, leukopenia, oligospermia, and impaired folate metabolism. Allergic and idiosyncratic side effects are fever, rash, haemolytic anaemia, neutropenia, worsened colitis, hepatitis, pancreatitis, and pneumonitis. Despite its side effects, sulfasalazine continues to be used because it is significantly less expensive than other 5-ASA agents. It should always be administered in conjunction with folate. Oral mesalamine agents have uncommon side effects of but include nausea, rash, diarrhoea, pancreatitis, and acute interstitial nephritis. Eighty percent of patients intolerant of sulfasalazine can tolerate mesalamine. Azo compounds are Balsalazide and olsalazine. Compared with mesalamine, there is less systemic absorption of 5-ASA and lower systemic side effects.
A variety of intravenous, oral, and topical corticosteroid formulations have been used in inflammatory bowel disease. Long-term use is associated with serious, potentially irreversible side effects and is to be avoided.
Mercaptopurine and azathioprine are drugs that are used in many patients with refractory Crohn’s disease and, increasingly, in patients with ulcerative colitis. About 1 person in 300 has a genetically acquired complete deficiency of one of the enzymes needed to metabolize these drugs placing them at risk of profound immunosuppression. Allergic and nonallergic side effects of mercaptopurine and azathioprine occur in 10% of patients, including pancreatitis, bone marrow suppression, infections, hepatitis or jaundice, and, potentially, a higher risk of tumours.
Methotrexate is increasingly used in the treatment of patients with Crohn’s disease, especially those who are intolerant of mercaptopurine. Methotrexate was originally used a chemotherapy for cancer, but at low doses it has anti-inflammatory properties. Side effects of methotrexate include nausea, vomiting, infections, bone marrow suppression, hepatitis, hepatic fibrosis, and life-threatening pneumonitis. Infliximab is an immunomodulating agent. Acute infusion reactions (nausea, headache, palpitations, shortness of breath, chest pain, fever, hypotension) occur in 6% of infusions Serious infections may occur in up to 5% of patients, including sepsis, pneumonia, abscess, and cellulitis. Patients treated with infliximab are at increased risk for the development of disseminated tuberculosis as well as other opportunistic infections. Prior to use of infliximab, patients should be screened for latent tuberculosis It is speculated but unproven that infliximab may increase the risk of lymphomas.