Abstract
Abstract only
e18193
Background: Steroids and Intravenous immunoglobulin (IVIG) are considered as the first line of therapy in immune thrombocytopenia (ITP) when treatment is indicated. Approximately 5% of patients with untreated CLL and 25-30% of patients with previously treated CLL have thrombocytopenia. There is limited data about ITP treatment patterns and therapeutic responses in patients with CLL. Methods: This is a retrospective cohort study using the 2016 National Inpatient Sample of adults ( > 18 years) hospitalized for ITP as the admitting diagnosis and CLL as a secondary diagnosis based on ICD-10 codes. Primary outcomes were rate of administration of IVIG, splenectomy, platelet transfusion and packed red blood cell transfusion during same admission. Length of hospitalization was a secondary outcome. Multivariate linear regression was used to adjust for cofounders of age, gender, race and Charlson comorbidity Index. STATA 15 was used for analysis. Results: 14,490 patients were admitted for ITP (56% females, mean age 46), of which 255 had CLL (95 females, mean age was 72.4). On multivariate linear regression there was a significant increase in the use of IVIG among ITP patients with CLL (OR: 2.11; 95%-CI 1.05-4.23, P = 0.03). While there was no difference in terms of splenectomy rate ( OR: 0.35, 95% CI 0.05 to 2.52, p = 0.28 ) or rate of platelet transfusion (Odds ratio 1.15, 95% CI 0.63 to 2.08, p = 0.65) and packed red blood cell transfusion (Odds ratio 1.03, 95% CI 0.44 to 2.39, p = 0.94) between patients who have ITP with CLL and patients admitted with ITP without CLL. No statistical difference was found in hospitalization length. Conclusions: Patients hospitalized for ITP with CLL were more likely to require IVIGs. This could be explained by several theories including the need for a more rapid increase in platelet count as thrombocytopenia may be more severe due to bone marrow infiltration by CLL, immune dysfunction and/or treatment induced thrombocytopenia. Additionally, CLL patients can have hypogammaglobinemia making them more likely to get IVIG as a treatment of choice for ITP and as an immune replacement. Also ITP patients with CLL may have less response to steroids, as was noted in a previous study. Fear of atypical infections due to steroids in CLL patients may result in increased IVIG use. Further research of the microenvironment of ITP in CLL patients might explain the difference in treatment pattern and therapeutic response in this population.