INTRODUCTION: MC is a chronic inflammatory condition of the colon characterized by watery, non-bloody diarrhea and is comprised of 2 subtypes: collagenous colitis (CC) and lymphocytic colitis (LC). Prior population-based studies of MC have been performed in regions such as Northern Europe and Olmsted County, MN which, in general, are racially homogenous. The purpose of our study is to describe the characteristics of patients (pts) with MC in a diverse, urban medical center in Bronx County, NY. METHODS: We retrospectively identified pts diagnosed with MC between January 2006 and June 2018 at our institution. Diagnosis was confirmed based on chart review of pts’ symptoms and histopathology. For each patient (pt), we recorded demographics, disease characteristics and co-morbidities. Our population characteristics were compared with those reported for pts with MC in Olmsted County, MN (Gentile et al. 2014). RESULTS: 76 pts were included in our study. The median age at diagnosis was 61.5 years (range 31 to 89 years) and 55 (72.4%) were female. There was a slight predominance of CC over LC (52.6% vs. 47.4%), with a trend towards significance compared with pts in Olmsted County, where CC was less common than LC (42.9% vs 57.1%, P = 0.10) (Table 1). Pts in Bronx County had lower rates of smoking (27.5% vs 52.5%, P < 0.01), but similar rates of autoimmune disease (21.4% vs. 19.2%, P = 0.75) compared with pts in Olmsted County. Race/ethnicity was reported in 65 pts, of whom 34 (52%) were Caucasian, 7 (11%) were African-American (AA), and 24 (37%) were Hispanic. When comparing pts based on race/ethnicity, AA and Hispanic pts were younger (P = 0.02) and had lower socioeconomic status (SES) (P < 0.01) than Caucasian pts (Table 2). No statistically significant differences in sex or MC subtype were seen among the 3 racial/ethnic groups. CONCLUSION: The racially/ethnically mixed pt population with MC in our urban healthcare setting has more CC predominance and less smoking exposure compared with the predominantly Caucasian population in a previously described US cohort. Age at diagnosis, female predominance and rates of concurrent autoimmune disease are similar. AA and Hispanic pts have an earlier age at diagnosis and lower SES than Caucasian pts. Our findings suggest that a diverse population may have a different presentation of MC than previously described. Larger population-based studies in these communities are needed to confirm our findings.