title: Natural history of azathioprine-associated lymphopenia in inflammatory bowel disease patients: a prospective observational study.
abstract: BACKGROUND
  Azathioprine (AZA) is commonly used in inflammatory bowel disease (IBD) patients. Lymphopenia is a recognized effect of this treatment, but lymphopenia-related complications in IBD patients have not been widely reported. The incidence and progression of AZA-induced lymphopenia in IBD patients is not well described. There is no consensus on its optimal management in this group.
  
  
  OBJECTIVE
  We assessed the incidence and progression of lymphopenia and its related complications in a cohort of IBD patients over a 14-month period in two large tertiary gastroenterology units. Analysis of prospectively collected data was performed.
  
  
  RESULTS
  Fifty-two patients were studied prospectively with a median age of 34 years. Eighteen patients (34.6%) developed lymphopenia (<1.0×10(9)/l) during the course of treatment and 10 of them had severe lymphopenia (<0.6×10(9)/l). Lymphopenia lasted on average 85.4 days and spontaneously resolved in 13 patients. No lymphopenia related-complications were documented. Patients treated with steroids had a significantly higher rate of lymphopenia (83.3 vs. 44.1%, P=0.0083).
  
  
  CONCLUSIONS
  Lymphopenia is common among IBD patients treated with AZA. However, it did not seem to be associated with a higher risk of opportunistic infections and spontaneously resolved in the majority of cases.
authors.affiliation: Department of Gastroenterology, Central Manchester University Hospitals NHS Foundation, University of Manchester, Manchester, UK.
authors.forename: Ahmad
authors.initials: A
authors.lastname: Al Rifai
authors.forename: Neeraj
authors.initials: N
authors.lastname: Prasad
authors.forename: Elinor
authors.initials: E
authors.lastname: Shuttleworth
authors.forename: Helen
authors.initials: H
authors.lastname: McBurney
authors.forename: Sudeep
authors.initials: S
authors.lastname: Pushpakom
authors.forename: Andrew
authors.initials: A
authors.lastname: Robinson
authors.forename: William
authors.initials: W
authors.lastname: Newman
authors.forename: Simon
authors.initials: S
authors.lastname: Campbell
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001379:Azathioprine / Q000009:adverse effects*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D015994:Incidence; D015212:Inflammatory Bowel Diseases / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology; D008231:Lymphopenia / Q000139:chemically induced* / Q000453:epidemiology / Q000276:immunology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D007166:Immunosuppressive Agents; D001379:Azathioprine