Assessment of Bone Microarchitecture in Patients with Systemic Mastocytosis and its Association with Clinical and Biochemical Parameters of the Disease.

Patients with systemic mastocytosis (SM) are at high risk of bone deterioration. However, the evaluation of bone microarchitecture in this disease remains unclear. We aimed to assess bone microarchitecture in patients with SM. This was a cross-sectional study of 21 adult patients with SM conducted in a quaternary referral hospital in Sao Paulo, Brazil. A healthy, age-, weight-, and sex-matched cohort of 63 participants was used to provide reference values for bone microarchitecture, assessed by high resolution peripheral quantitative computed tomography (HR-pQCT). Total volumetric bone mineral density (vBMD), cortical vBMD, and cortical thickness at the radius were significantly lower in the control group compared with the SM group (all P < 0.001). Patients with aggressive SM had significantly lower trabecular number (Tb.N) (P = 0.035) and estimated failure load (F.load) (P = 0.032) at the tibia compared with those with indolent SM. Handgrip strength was significantly higher in patients who had more Tb.N at the radius (ρ, 0.46; P = 0.036) and tibia (ρ, 0.49; P = 0.002), and lower who had more trabecular separation at the radius (ρ, -0.46; P = 0.035) and tibia (ρ, -0.52; P = 0.016). Strong and positive associations between F.load (ρ, 0.75; P < 0.001) and stiffness (ρ, 0.70; P < 0.001) at the radius, and between F.load at the tibia (ρ, 0.45; P = 0.038) were observed with handgrip strength. In this cross-sectional study, aggressive SM was more susceptible to bone deterioration compared with indolent SM. In addition, the findings demonstrated that handgrip strength was associated with bone microarchitecture and bone strength.

Effect of a single high dose of vitamin D3 on cytokines, chemokines, and growth factor in patients with moderate to severe COVID-19.

BACKGROUND: The modulating effect of vitamin D on cytokine concentrations in severe coronavirus disease 2019 (COVID-19) remains unknown. OBJECTIVES: We aimed to investigate the effect of a single high dose of vitamin D3 on cytokines, chemokines, and growth factor in hospitalized patients with moderate to severe COVID-19. METHODS: This is a post hoc, ancillary, and exploratory analysis from a multicenter, double-blind, placebo-controlled, randomized clinical trial. Patients with moderate to severe COVID-19 were recruited from 2 hospitals in São Paulo, Brazil. Of 240 randomly assigned patients, 200 were assessed in this study and randomly assigned to receive a single oral dose of 200,000 IU vitamin D3 (n = 101) or placebo (n = 99). The primary outcome was hospital length of stay, which has been published in our previous study. The prespecified secondary outcomes were serum concentrations of IL-1ß, IL-6, IL-10, TNF-α, and 25-hydroxyvitamin D. The post hoc exploratory secondary outcomes were IL-4, IL-12p70, IL-17A, IFN-γ, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-8, IFN-inducible protein-10 (IP-10), macrophage inflammatory protein-1ß (MIP-1ß), monocyte chemoattractant protein-1 (MCP-1), vascular endothelial growth factor (VEGF), and leukocyte count. Generalized estimating equations for repeated measures, with Bonferroni's adjustment, were used for testing all outcomes. RESULTS: The study included 200 patients with a mean ± SD age of 55.5 ± 14.3 y and BMI of 32.2 ± 7.1 kg/m2, of which 109 (54.5%) were male. GM-CSF concentrations showed a significant group-by-time interaction effect (P = 0.04), although the between-group difference at postintervention after Bonferroni's adjustment was not significant. No significant effects were observed for the other outcomes. CONCLUSIONS: The findings do not support the use of a single dose of 200,000 IU vitamin D3, compared with placebo, for the improvement of cytokines, chemokines, and growth factor in hospitalized patients with moderate to severe COVID-19.This trial was registered at clinicaltrials.gov as NCT04449718.

Visceral adipose tissue in granulomatosis with polyangiitis: association with disease activity parameters.

OBJECTIVE: To assess the body composition (BC) of patients with granulomatosis with polyangiitis (GPA) compared to healthy controls, emphasizing visceral adipose tissue (VAT) and associated BC parameters with disease activity, the damage index, and inflammatory parameters in patients with GPA. METHODS: This study was conducted in 43 patients with GPA and 43 healthy controls matched by sex, age, and body mass index (BMI). BC was analyzed using dual-energy X-ray absorptiometry (DXA). The fat mass parameters evaluated were total fat mass (FM), adiposity (%), the fat mass index (FMI: fat mass/ht2), and VAT (g, cm2, cm3). Disease activity was assessed by the Birmingham Vasculitis Activity Score (BVAS). Damage was assessed by the Vasculitis Damage Index (VDI). C-reactive protein (CRP) and the erythrocyte sedimentation rate (ESR) were measured. RESULTS: Comparing patients with GPA with healthy controls, patients had a significantly greater VAT (VAT in g: 685.81 ± 306.10 vs. 581.21 ± 235.57, p = 0.04; VAT in cm2: 142.23 ± 63.48 vs. 119.84 ± 49.54, p = 0.03; VAT in cm3: 741.33 ± 330.97 vs. 628.44 ± 254.66, p = 0.04). Patients with higher VAT (≥ 768 g) had an increased value of ESR (22.77 ± 26.79 vs. 11.57 ± 11.30 mm/1st hour, p = 0.04) and an increased value of BVAS (3.18 ± 4.15 vs. 0.90 ± 1.70, p = 0.01) when compared to patients with less VAT (< 768 g). CONCLUSION: Patients with GPA have altered BC compared to healthy controls. Moreover, higher VAT was associated with disease activity and higher inflammatory markers, suggesting a relationship between GPA activity and adiposity parameters. Key points • Granulomatosis with polyangiitis patients have increased visceral adipose tissue when compared to health controls; • Granulomatosis with polyangiitis patients with higher values of visceral adipose tissue have worse disease activity and higher inflammatory markers; • This paper represents important contribution to the well-studied association between vasculitis and inflammatory markers, adding the role of adipose visceral tissue in the disease physiopathology.