Search in the Abstract Database

Search Abstracts 2016

* = Presenting author

P681 Long-term outcomes of a cohort of Crohn’s disease patients with idiopathic lymphopenia

V. Roales1, C. Alba1, J. L. Mendoza1, D. Olivares1, E. Rey2, C. Taxonera*1

1Hospital Clinico San Carlos, IBD Unit, Madrid, Spain, 2Hospital Clinico San Carlos, Gastroenterology, IdiSSC, Madrid, Spain

Background

Patients with Crohn´s disease (CD) frequently present low peripheral lymphocyte counts which may be associated with the activity of disease, the effects of therapy and the presence of an abnormal Treg or Breg function. Data regarding clinical outcomes in CD patients with peripheral lymphopenia are scarce. The aim of this study was to assess the differences in baseline characteristics and clinical outcomes between 2 cohorts of CD patients: with and without lymphopenia

Methods

In this observational cohort study, a retrospective search in prospectively maintained databases from our IBD Unit was performed between 2001 and 2007 for CD patients with lymphopenia. The study population comprised all CD patients who had up to 1.200 lymphocytes in any determination and in at least 6 blood samples separated by 9 months. We excluded patients who had previous resective surgery and those with prior drug use or associated pathology that could affect the lymphocyte count. Patients without tendency to lymphopenia acted as the control cohort. Baseline characteristics (sex, tobacco use, Montreal classification of age and disease location) and clinical outcomes during a follow-up of 6 years were recorded. We assessed the need for surgery or treatment with immunosuppressants or biological drugs and their side effects. Event-free survival was estimated using Cox proportional hazard regression analysis

Results

Amongst 205 CD patients screened, 29 patients (14%) fulfilled all inclusion/exclusion criteria and composed the cohort with persistent lymphopenia. The control cohort included 115 patients with no tendency to lymphopenia. Regarding baseline characteristics, patients with persistent lymphopenia showed significantly different higher rates of Montreal classification of age A3 (13/29 [44.8%] vs 29/115 [25.2%] for patients with or without lymphopenia respectively; p = 0.03). Concerning the long-term clinical outcomes, CD patients with persistent lymphopenia had a significantly higher adjusted rate of resective surgery (HR 2.7; 95% CI: 1.1–6.9; p = 0.03). In all, 7/29 (24.1%) patients with lymphopenia vs 12/115 [10.4%] patients without lymphopenia needed resective surgery. Patients with persistent lymphopenia also had a significantly higher adjusted rate of myelotoxicity associated to the use of immunosuppressants (HR 8.2; 95% CI: 3.4–19.9; p < 0.001)

Conclusion

Our results supported the existence of a lymphopenic phenotype in CD. CD patients with persistent lymphopenia are more likely to require resective surgery. The likelihood of developing myelotoxicity with immunosuppressive therapy was 8 times higher in patients with persistent lymphopenia. Therefore, treatment with immunosuppressive drugs in patients with persistent lymphopenia should be closely monitored