Liver Fibrosis and Steatosis in Alström Syndrome: A Genetic Model for Metabolic Syndrome

Alström syndrome (ALMS) is an ultra-rare monogenic disease characterized by insulin resistance, multi-organ fibrosis, obesity, type 2 diabetes mellitus (T2DM), and hypertriglyceridemia with high and early incidence of non-alcoholic fatty liver disease (NAFLD). We evaluated liver fibrosis quantifying liver stiffness (LS) by shear wave elastography (SWE) and steatosis using ultrasound sonographic (US) liver/kidney ratios (L/K) in 18 patients with ALMS and 25 controls, and analyzed the contribution of metabolic and genetic alterations in NAFLD progression. We also genetically characterized patients. LS and L/K values were significantly higher in patients compared with in controls (p < 0.001 versus p = 0.013). In patients, LS correlated with the Fibrosis-4 Index and age, while L/K was associated with triglyceride levels. LS showed an increasing trend in patients with metabolic comorbidities and displayed a significant correlation with waist circumference, the homeostasis model assessment, and glycated hemoglobin A1c. SWE and US represent promising tools to accurately evaluate early liver fibrosis and steatosis in adults and children with ALMS during follow-up. We described a new pathogenic variant of exon 8 in ALMS1. Patients with ALMS displayed enhanced steatosis, an early increased age-dependent LS that is associated with obesity and T2DM but also linked to genetic alterations, suggesting that ALMS1 could be involved in liver fibrogenesis.

Splenic Doppler impedance indices estimate splenic congestion in patients with right-sided or congestive heart failure

Splenic Doppler impedance indices are measurements of splenic congestion in chronic liver disease. It is not known whether they can also assess splenic congestion in patients affected by right-sided or congestive heart failure. We analyzed splanchnic hemodynamics with Doppler ultrasound and systemic hemodynamics with right-sided heart catheterization in patients with heart failure. Splenic pulsatility index (PI) was higher in patients with heart failure (48 patients) compared with healthy subjects (39 patients) (1.19 ± 0.41 vs. 0.73 ± 0.11, p < 0.0001) and was related to hepatic vein diameter (p = 0.02). Splenic PI was not related to systemic arterial pressure, cardiac output, systemic vascular resistance or splenic arterial resistance, whereas it was related to right atrial mean pressure (p = 0.0003) and to right ventricle end-diastolic pressure (p = 0.011) (34 patients). In conclusion, splenic PI is a measurement of splenic congestion caused by an increase in venous outflow resistance. It can estimate splenic congestion in patients with right-sided or congestive heart failure.