Serious Infectious Events and Immunoglobulin Replacement Therapy in Patients With Autoimmune Disease Receiving Rituximab: A Retrospective Cohort Study.

BACKGROUND: Rituximab (RTX) is widely administered to patients with autoimmune disease (AID). This study aimed to estimate the incidence of serious infectious events (SIEs) after RTX initiation in patients with AID. We also described the characteristics and risk factors of SIEs, and immunoglobulin replacement therapy (IgRT) strategies. METHODS: Patients treated between 2005 and 2016 were included in this retrospective monocentric cohort study. An RTX course was defined as the complete RTX treatment regimen received by a given patient for AID. SIEs and IgRT were right-censored at 24 months after RTX initiation. RESULTS: Two hundred twenty-one patients were included (corresponding to 276 RTX courses). Reasons for RTX initiation included connective tissue disease (38%), systemic vasculitis (36%), and autoimmune cytopenia (22%). The 1- and 2-year incidences of SIEs were 17.3 (95% confidence interval [CI], 12.0-22.5) and 11.3 (95% CI, 8.1-14.5) per 100 person-years, respectively. Forty-seven SIEs were observed, mostly comprising pneumonias (45%) and bacteremias (21%). When documented, the microorganisms were bacterial (55%) and fungal (12%). Identified risk factors of SIEs were age, history of diabetes, history of cancer, concomitant steroid treatment, and low CD4 lymphocyte count at RTX initiation. IgRT was started in 22 RTX courses (8%). CONCLUSIONS: In patients with AID treated with RTX, the 1- and 2-year incidence of SIE was 17.3 and 11.3 per 100 person-years, respectively. Reports of SIE characteristics, risk factors, and IgRT strategies highlight the need for an appropriate and individualized assessment prior to and following RTX to prevent SIEs, particularly in patients with comorbidities.

Patients with Crohn's Disease with High Body Mass Index Present More Frequent and Rapid Loss of Response to Infliximab.

BACKGROUND: Infliximab (IFX) is effective in inducing and maintaining remission in patients with luminal and anoperineal Crohn's disease (CD). However, treatment failure within 12 months after initiating IFX is observed in a significant proportion of patients. The aim of the present study was to determine whether the body mass index (BMI) affects response to IFX during the first year of treatment in patients with CD. METHODS: All patients with luminal CD who began IFX between January 2010 and May 2014 were prospectively included. BMI was calculated before IFX treatment was begun, and patients were divided into 3 groups: normal BMI (BMI < 25 kg/m), overweight patients (BMI of 25.0-30 kg/m), and obese patients (BMI > 30.0 kg/m). The primary outcome was to evaluate the rate and delay of IFX optimization during the first year of treatment among normal weight, overweight, and obese patients. RESULTS: One hundred forty patients were included. Demographic and clinical characteristics at IFX initiation were comparable among the 3 groups. Within 12 months after the initiation of IFX, the rate of IFX optimization was significantly higher in overweight and obese patients than in the normal BMI group: 52%, 56%, and 20%, respectively (P = 0.0002). The median time until optimization of IFX was significantly shorter in overweight and obese patients than in the normal BMI group: 7, 7, and 10 months, respectively (P = 0.03). A BMI >25 kg/m was significantly associated with IFX optimization within 12 months on multivariate analysis. CONCLUSION: This is the first study to show that optimization of IFX is more frequent and faster in obese and overweight patients with CD and occurs within 12 months after beginning IFX, suggesting that an induction regimen with higher doses of IFX and a tight control of IFX concentrations may be needed in these patients.