Introduction: Langerhans-cell histiocytosis (LCH) is a rare disorder that combines features of carcinogenesis and chronic inflammation with specific predilection for the Hypothalamic-Pituitary system. Chronic inflammation, insulin resistance (IR) and hypopituitarism have been associated with increased risk for cardiovascular disease. The purpose of this study was to investigate structural and functional vascular properties in treated patients with multisystemic LCH and their associations with inflammation markers and insulin resistance indices.

Methods: We studied 8 patients with multisystem LCH (age:38.38±4.49 yrs; BMI: 25.99±1.26 kg/m²) and 24 controls (age:37.92±2.50 yrs; BMI:25.03± 0.68 kg/m²) matched for sex, age and BMI. Structural properties were assessed by intima media thickness estimation in common carotid artery (mean value right and left, MCCA, mm) and functional by endothelial function, using flow-mediated dilatation (FMD, %) on the brachial artery. Nitrate-induced dilatation (NID) was applied to exclude smooth muscle cells injury. C-reactive protein (CRP), fasting glucose, insulin, total cholesterol, HDL, triglycerides were measured; Waist-to-hip ratio (WHR), LDL and IR indices (glucose-to-insulin ratio, HOMA, QUICKI) were calculated.

Results: No difference in IMT (p = 0.11) and FMD (p = 0.74) values was detected among LCH patients and controls. Higher CRP (p = 0.003) and insulin levels (p = 0.035), and higher WHR (p = 0.017) and lower glucose-to-insulin ratio (p = 0.003) values were observed in LCH patients.

Conclusions: Treated patients with multisystemic LCH do not present alteration in vascular bed properties. However, such patients should be followed with caution as higher values of chronic inflammatory markers and insulin resistance indices were detected. Further larger scale studies are required to clarify whether these findings are inherent to the disease process or secondary to treatment.