Azathioprine and mercaptopurine in the management of patients with chronic, active microscopic colitis

BACKGROUND

Microscopic colitis (MC) is a common chronic diarrhoeal disease, and remission can be induced with budesonide. However, diarrhoea relapses frequently when budesonide is tapered and a few patients become budesonide intolerant.

AIM

To examine retrospectively the effect of azathioprine (AZA) and mercaptopurine (MP) in patients with chronic, active MC.

METHODS/PATIENTS

Data on all MC patients who received AZA or MP in the years 1997-2011 at three centres representing three countries were pooled for analysis. The indications for thiopurine therapy were frequent relapses after short-term treatment (N = 26), budesonide dependency on 6 mg (N = 15) and budesonide intolerance (N = 5). The response to thiopurine treatment was defined as clinical remission, intolerance or nonresponse.

RESULTS

Forty-six MC patients (32 CC and 14 LC), 32 female; median age 59 years (range: 36-83) with a median disease duration of 3 years (range: 0.5-18) were included. Thirteen patients (28%) achieved long-term clinical remission on AZA therapy. AZA failed in 31 patients (67%) due to intolerance and in 2 patients (4%) because of nonresponse. Thirteen of 31 AZA-intolerant patients were switched to MP and 6 patients (46%) obtained clinical remission. Thus, the overall response rate to thiopurines was 19/46 (41%). The main side effects were nausea/vomiting and abnormally elevated liver enzymes.

CONCLUSIONS

In this retrospective case series, the majority of chronic, active MC patients were intolerant to AZA leading to cessation of treatment. However, further studies are needed to explore the efficacy, acceptance, tolerance and safety of MP in patients with chronic, active MC refractory to budesonide.

Vitamin status in patients with inflammatory bowel disease

The status of water- and fat-soluble vitamins was prospectively evaluated in 23 patients (13 men, 10 women, mean age 33 +/- 3 yr) admitted to the hospital with acute or subacute attacks of inflammatory bowel disease. Protein-energy status was also assessed by means of simultaneous measurement of triceps skinfold thickness, mid-arm muscle circumference, and serum albumin. Fifteen patients (group A) had extensive acute colitis (ulcerative or Crohn's colitis), and eight cases (group B) had small bowel or ileocecal Crohn's disease. Eighty-nine healthy subjects (36 men, 53 women, mean age 34 +/- 2 yr) acted as controls. In both groups of patients, the levels of biotin, folate, beta-carotene, and vitamins A, C, and B1 were significantly lower than in controls (p less than 0.01). Plasma levels of vitamin B12 were decreased only in group B (p less than 0.01), whereas riboflavin was lower in group A (p less than 0.01). The percentage of patients at risk of developing hypovitaminosis was 40% or higher for vitamin A, beta-carotene, folate, biotin, vitamin C, and thiamin in both groups of patients. Although some subjects had extremely low vitamin values, in no case were clinical symptoms of vitamin deficiency observed. Only a weak correlation was found between protein-energy nutritional parameters and vitamin values, probably due to the small size of the sample studied. The pathophysiological and clinical implications of the suboptimal vitamin status observed in acute inflammatory bowel disease are unknown. Further studies on long-term vitamin status and clinical outcome in these patients are necessary.