The role of elastography in alcoholic liver disease: fibrosis staging and confounding factors, a review of the current literature.

INTRODUCTION: Alcohol-related liver disease (ALD) was estimated to have a prevalence of 2% among the USA population. Since severe fibrosis in compensated patients is the main predictor of long-term survival, it is of utmost importance to early detect patients with severe fibrosis before decompensation occurs. Liver elastography has been used to stage liver fibrosis. However, there is a widespread lack in guidelines for the correct use of liver stiffness (LS) in ALD. EVIDENCE ACQUISITION: A structured search was carried out on MEDLINE/PubMed database. From the original 225 research articles identified, only 12 studies met the inclusion criteria, with 10 studies being eventually included. EVIDENCE SYNTHESIS: According to reported data, patients with aspartate aminotransferase (AST)>100 IU/L and 50 IU/L showed significantly higher values of LS if compared to patients with the same fibrosis stage. Also, excessive alcohol consumption greatly influences elastography, leading to false fibrosis staging. When LS values >5-6 kPa are detected, several aspects should be taken into account. First of all, the patient should be asked about the current alcohol consumption (i.e. active vs. abstinence, determination of abstinence period, and quantification of alcohol intake), and if the patient is an active drinker, liver elastography can be repeated after a complete abstinence period of at least two weeks. and if the patient is an active drinker, liver elastography can be repeated after a complete abstinence period of at least two weeks. Secondly, clinicians should check liver transaminases level, and if AST are above 100 IU/L, they should be aware of a possible overestimation of fibrosis. However, whether transaminases-adapted cut-off values should be used for ad-hoc decisions in patients with no time or option to withdraw from alcohol consumption is still a matter of debate. CONCLUSIONS: We hope that our review article may serve as a reference point in the prospect of futures guidelines.

Cardiovascular autonomic dysfunction in patients with idiopathic diabetes insipidus.

INTRODUCTION: Central diabetes insipidus (DI) is a rare disease characterized by the excretion of excessive volumes of dilute urine due to reduced levels of the antidiuretic hormone arginine vasopressin (AVP), caused by an acquired or genetic defect in the neurohypophysis. The aim of this study was to identify any autonomic dysfunction (AD) in patients with DI as a possible cofactor responsible for their reportedly higher mortality. METHODS: The study involved 12 patients (6 females) with central idiopathic DI and a well-controlled electrolyte balance, and 12 controls matched for age, sex and cardiovascular risk factors, who were assessed using the tilt, lying-to-standing, hand grip, deep breath, Valsalva maneuver and Stroop tests. RESULTS: The tilt test showed a significantly more pronounced decrease in both systolic (- 20.67 ± 18 vs. - 1.92 ± 6.99 mmHg, p = 0.0009) and diastolic blood pressure (- 10.5 ± 14.29 vs. - 1.5 ± 5 mmHg, p = 0.012) in patients than in controls. Three patients with DI had to suspend the test due to the onset of syncope. The lying-to-standing test also revealed a marked reduction in blood pressure in patients with DI (1.05 ± 0.13 vs. 1.53 ± 0.14, p = 0.0001). Similar results emerged for the Valsalva maneuver (Valsalva ratio, 1.24 ± 0.19 vs. 1.79 ± 0.11, p < 0.0001) and deep breath test (1.08 ± 0.11 vs. 1.33 ± 0.08, p < 0.0001). CONCLUSIONS: All the principal autonomic tests performed in the study were concordant in indicating that patients with central DI have an impaired autonomic nervous system function despite a normal hydroelectrolytic balance under desmopressin therapy. This impairment may reflect damage to the autonomic system per se and/or the absence of any vasoactive effect of AVP on vascular smooth muscle. In our opinion, patients with central DI should be educated on how to prevent orthostatic hypotension, and pharmacological treatment should be considered for patients with a more marked impairment.