S3215 Hermansky-Pudlak-Associated IBD: Is It the Same? Description of a Puerto Rican Cohort

Abstract

INTRODUCTION: Hermansky-Pudlak Syndrome (HPS) is the most common single gene disorder in Puerto Rico. It is a rare autosomal recessive disorder due to aberrant biogenesis of lysosome-related organelles leading to oculocutaneous albinism, bleeding diathesis, and involvement in other organs. About 30% of patients with HPS develop a form of Crohn’s-like inflammatory bowel disease (IBD), granulomatous enterocolitis. Whether this is a manifestation of HPS or true IBD is still in debate. We wish to describe a group of patients with HPS-associated IBD. METHODS: This is a prospective cohort study in which phenotypically identified patients with HPS and concomitant IBD are recruited. After informed consent, a questionnaire with demographic and medical data is administered through patient interview and record review is performed. The variables collected are sex, HPS genotype, age at the time of IBD diagnosis, comorbidities, IBD location and behavior according to Montreal Classification, surgical interventions, medications, and extra-intestinal manifestations (EIM). This study is approved by the IRB. RESULTS: Ten patients with HPS and concomitant IBD were identified in our clinics - 5 males and 5 females. HPS genotype in 9 showed 8 were HPS-1 and 1 was HPS-3. The mean age at the time of IBD diagnosis was 22 ± 10 years. Six were diagnosed between ages 17 and 40 years and 4 patients were diagnosed at ≤16 y/o. Seven patients had colonic involvement, 3 had ileocolonic involvement. Sixty percent of patients had an advanced penetrating behavior and 50% had perianal involvement. Six patients had some type of surgical intervention. Three patients were on both a biologic and an immunomodulator (IMM), 5 were on a biologic alone, 1 on IMM alone, and 1 without maintenance treatment. The most frequent EIM was anemia in 40% of patients. CONCLUSION: HPS patients had a severe course of IBD, as shown by phenotype, surgery, and use of biologics. A younger age at diagnosis and a higher than usual prevalence of perianal disease also predict a complicated course. Further studies are necessary to determine if HPS-associated IBD is related to the genetic defect and if this may result in a different clinical course than idiopathic IBD.