The choice of treatment approach for mild and moderate ulcerative colitis: A review

Ulcerative colitis (UC) is a chronic immune-inflammatory disease of unknown etiology characterized by continuous non-granulomatous inflammation of the colon mucosa. Inflammation may be limited to the rectum but often extends to the proximal colon. Mild and moderate UC are diagnosed in most patients, especially in distal colon involvement. The goal of UC therapy is to achieve endoscopic remission. Clinical remission is an intermediate goal. Current Russian and international clinical guidelines recommend 5-aminosalicylic acid (mesalazine), an effective anti-inflammatory drug with the best safety profile among currently used classes of drugs, as first-line therapy for mild and moderate UC. The clinical efficacy of mesalazine depends on its concentration in the mucosa of the affected colon; therefore, rectal formulations are recommended for the treatment of distal UC. Suppositories are preferred for the treatment of ulcerative proctitis, as they deliver the highest concentration of the active substance to the rectum. If the inflammation spreads to the proximal colon, the optimal rectal formulations are microclysters or foam. Combination therapy with oral and rectal formulations of mesalazine is recommended for left-sided and total UC. Mesalazine granules deliver a higher concentration of mesalazine in the distal colon than tablets, so they are preferred in left-sided UC. The combination of mesalazine granules with suppositories can significantly improve treatment compliance. In case of insufficient response to mesalazine, it is recommended to add rectal budesonide. Compared to systemic glucocorticoids, it has high local anti-inflammatory activity and minimal side effects. This literature review presents current regimens and algorithms for the treatment of distal and total UC with oral and rectal formulations of mesalazine and rectal budesonide.