Case report: Pentoxifylline treatment in microscopic colitis

Rationale: Microscopic colitis is a common cause of diarrhea. Pentoxifylline, a xanthine derivative with anti-tumor necrosis factoralpha properties, is prescribed for intermittent claudication and other disorders. Our goal was to evaluate the outcomes of patients with microscopic colitis treated with pentoxifylline. Patient concerns: Nine patients with microscopic colitis (8 collagenous colitis and 1 lymphocytic colitis) seen at Mayo Clinic, Rochester, between January 1, 1997 and November 30, 2016, were included. The median age was 56.9 years (range 51.6-60.2), 8 were female (89%), and the median disease duration was 64.8 months (range 60-109). The indications for treatment were budesonide refractoriness in 7 patients, budesonide dependence in 1 patient, and budesonide intolerance in 1 patient. Diagnoses: A histological diagnosis of microscopic colitis was confirmed in all patients. Interventions: Pentoxifylline 400 mg three times a day was used for a median of 3 months (range 2.5-8.3). Outcomes: Complete response occurred in 1 patient (11%) and partial response in 3 patients (33%). The patient who achieved complete response was treated with pentoxifylline due to budesonide intolerance, and completed 43 months of successful maintenance therapy. There were no adverse effects reported. Lessons: The majority of budesonide-experienced patients with active microscopic colitis did not respond to pentoxifylline. However, it was well-tolerated, with 1 patient achieving long-term remission and one-third of the cohort having a partial response. Larger controlled studies are required to evaluate the efficacy of pentoxifylline and predictors of response in microscopic colitis. In particular, patients who are not budesonide-refractory may be more likely to respond. Abbreviations: CC = collagenous colitis, LC = lymphocytic colitis, MC = microscopic colitis, TNF-α = tumor necrosis factoralpha.