Increased Plasma Levels of Triglyceride-Enriched Lipoproteins Associate with Systemic Inflammation, Lipopolysaccharides, and Gut Dysbiosis in Common Variable Immunodeficiency.

PURPOSE: Triglycerides (TG) and their major transport lipoprotein in the circulation (VLDL) appear to be related to inflammation. Patients with common variable immunodeficiency (CVID) have inflammatory complications associated with gut microbial dysbiosis. We hypothesized that CVID patients have disturbed TG/VLDL profiles associated with these clinical characteristics. METHODS: We measured plasma concentrations of TGs, inflammatory markers, and lipopolysaccharide (LPS) in 95 CVID patients and 28 healthy controls. Additionally, in 40 CVID patients, we explored plasma lipoprotein profiling, fatty acid, gut microbial dysbiosis, and diet. RESULTS: TG levels were increased in CVID patients as compared to healthy controls (1.36 ± 0.53 mmol/l versus 1.08 ± 0.56 [mean, SD], respectively, P = 0.008), particularly in the clinical subgroup "Complications," characterized by autoimmunity and organ-specific inflammation, compared to "Infection only" (1.41 mmol/l, 0.71[median, IQR] versus [1.02 mmol/l, 0.50], P = 0.021). Lipoprotein profile analyses showed increased levels of all sizes of VLDL particles in CVID patients compared to controls. TG levels correlated positively with CRP (rho = 0.256, P = 0.015), IL-6 (rho = 0.237, P = 0.021), IL-12 (rho = 0.265, P = 0.009), LPS (r = 0.654, P = 6.59 × 10-13), CVID-specific gut dysbiosis index (r = 0.315, P = 0.048), and inversely with a favorable fatty acid profile (docosahexaenoic acid [rho = - 0.369, P = 0.021] and linoleic acid [rho = - 0.375, P = 0.019]). TGs and VLDL lipids did not appear to be associated with diet and there were no differences in body mass index (BMI) between CVID patients and controls. CONCLUSION: We found increased plasma levels of TGs and all sizes of VLDL particles, which were associated with systemic inflammation, LPS, and gut dysbiosis in CVID, but not diet or BMI.

Real-World Experiences With Facilitated Subcutaneous Immunoglobulin Substitution in Patients With Hypogammaglobulinemia, Using a Three-Step Ramp-Up Schedule.

Immunoglobulin replacement therapy with facilitated subcutaneous immunoglobulin (fSCIg) can be self-administrated at home and given at longer intervals compared to subcutaneous immunoglobulin (SCIg) therapy, but real-word experience of home-based fSCIg therapy is limited. Herein we present our real-word clinical experiences with home-based fSCIg therapy using a three-step ramp-up schedule. We registered data from all patients with immunodeficiency starting fSCIg from 01.01.2017 to 31.12.2019. For comparison we also included patients starting conventional SCIg training. Fifty-four patients followed for a median of 18 months (IQR 12, range 0-40), received fSCIg training, and 84 patients received conventional SCIg training. Out of 54 patients starting with fSCIg, 41 patients had previous experience with conventional SCIg therapy, and the main reason for starting fSCIg was 'longer intervals between therapies' (n=48). We found an increase in training requirement for fSCIg (3 ± 1 [2-9] days) compared to conventional SCIg (2 ± 0 [1-7] days), P< 0.001 (median ± IQR, [range]). For fSCIg training, IgG levels were stable from baseline (8.9 ± 2.3 g/L), 3-6 months (10.2 ± 2.2 g/L) and 9-12 months (9.9 ± 2.3 g/L), P= 0.11 (mean ± SD). The most common side-effect was: 'rubor around injection site' (n=48, 89%). No patients experienced severe adverse events (grade 3-4). Thirteen patients (24%) discontinued fSCIg therapy due to local adverse events (n=9), cognitive/psychological difficulties (n=6) and/or systemic adverse events (n=3). In conclusion, fSCIg training using a three-step ramp-up schedule is safe and well tolerated by the majority of patients, but requires longer training time compared to conventional SCIg.