Relevant infections in inflammatory bowel disease, their relationship with immunosuppressive therapy and their effects on disease mortality.

Abstract

INTRODUCTION\nThere is controversy as to whether the risk of relevant infection in IBD is related to immunosuppressants or the disease itself.\n\n\nAIMS\nTo evaluate: 1) the life-long prevalence and types of relevant infections in patients with IBD related to immunosuppressive treatment, and 2) the relationship of both infection and patient comorbidity to mortality.\n\n\nMETHODS\nObservational multicentre retrospective study of IBD patients that presented a relevant infection. For each case, four periods of infection exposure were analysed: P1: pre-IBD diagnosis, P2: from IBD diagnosis to immunosuppressant initiation, P3: during immunosuppressant therapy, and P4: after treatment withdrawal.\n\n\nRESULTS\nThe life-long prevalence of relevant infection in the total cohort of patients (6,914) was 3%, and 5% in immunosuppressed patients (4,202). 366 relevant infections were found in 212 patients (P1: 9, P2: 17, P3: 334, and P4: 6). Differences between periods were significant (p< 0.0001). The most frequent types of infection were respiratory, intestinal and urinary. The most frequent opportunistic infections were tuberculosis (prevalence: 2.6/1000) and herpes zoster (prevalence: 3.9/1000). Herpes zoster infection was associated with thiopurines alone or in combination with anti-TNF in 75% of the cases, whereas tuberculosis was associated with anti-TNF in 94% of patients. The overall mortality was 4.2%. Infection-related mortality was 2.8% and it was not influenced by comorbidity.\n\n\nCONCLUSIONS\nRelevant infections in IBD patients are rare and appear to be related to immunosuppression. Relevant infection is a major cause of death in IBD.