Marco Valgimigli

Measurement of oxidative stress in human liver by EPR spin-probe technique

A method for the measurement of reactive oxygen species (ROS) in human hepatic tissue has been developed. The method is based on the EPR detection of the nitroxide radical produced by reaction of the hydroxylamine spin-probe bis(1-hydroxy-2,2,6,6-tetramethyl-4-piperidinyl)decandioate with ROS generated under pseudo-physiologic conditions in fine needle biopsies of healthy (10 controls) and diseased (22 patients) human liver. Measures of malonaldehyde in 9 liver biopsies (3 controls and 6 patients) have also been obtained by high pressure liquid chromatography and values parallel those obtained by the spin-probe technique. The amount of ROS found in healthy human liver (median = 1.8 × 10-11 mol/mg) was significantly lower than values found in liver affected by hepatitis B (median = 5.8 × 10-10 mol/mg; p < 0.02) or by hepatitis C (median = 2.7 × 10-9 mol/mg; p < 0.003) as well as compared to some other non-viral liver diseases (NVLD): autoimmune hepatitis, primary biliary cirrhosis, primary schlerosing cholangitis (median = 9.8 × 10-9 mol/mg; p < 0.005). NVLD also showed significantly higher ROS levels compared to hepatitis B (p < 0.04) and hepatitis C (p < 0.04). The mechanism, potentiality and limitations of our method are discussed.

Serum xanthine oxidase in human liver disease

OBJECTIVES:High concentrations of serum xanthine oxidase (XO) have been reported during human liver disease and hepatocyte injury in experimental settings. However, it is unclear whether this elevation reflects hepatocyte necrosis or has a different meaning.METHODS:The serum level of XO in 64 patients with chronic liver disease (17 patients with cirrhosis, 30 with chronic hepatitis, and 17 with cholestatic disorders) and in 12 control subjects was determined by a competitive ELISA. Conventional serum markers of liver damage were assessed in all patients, and grading and staging were scored in the chronic hepatitis group according to Knodell.RESULTS:The XO serum levels were significantly higher in the patients than in the controls. The differences were also significant when controls were compared to patients with chronic hepatitis and cholestatic disorders separately, but not when compared to the cirrhosis group. Patients with cholestatic disorders had XO values higher than those of patients with cirrhosis or chronic hepatitis. XO levels did not correlate with stage and grade in chronic hepatitis group. We found a weak but significant positive correlation in patients between XO serum level and γ-glutamyl transpeptidase (r = 0.37). This correlation was stronger when chronic hepatitis (r = 0.42) and, especially cholestatic disorders (r = 0.71), were separately tested, but was absent in the cirrhosis group. The XO values positively correlated with alkaline phosphatase in patients with cholestatic disorders. A level of serum XO >32 μg/ml specifically identified cholestatic disorders in our study population.CONCLUSIONS:A marked elevation of serum XO in patients with chronic liver disease seems to reflect the presence of cholestasis. No correlation between XO levels and histological or serum evidence of hepatocyte necrosis was found in these patients.

Duplex Doppler findings in splenic arteriovenous fistula.

Splenic arteriovenous fistula (AVF) is a rare cause of portal hypertension. An early diagnosis is crucial because lethal complications may occur if the disease is not treated. We report a case of AVF in a noncirrhotic patient in whom the diagnosis was made by duplex sonography. This technique can differentiate between AVF and other, more common vascular abnormalities in the left upper quadrant in patients with portal hypertension. Duplex sonography can therefore be recommended as the first imaging approach in this population.

Left ventricular volumes in liver cirrhosis.

BACKGROUND Patients with alcoholic cirrhosis have left ventricular dimensions similar to controls. Few data have been reported in patients with cirrhosis of viral origin. AIM To assess left ventricular dimensions in patients with pure viral cirrhosis. PATIENTS AND METHODS Thirty patients with virus-related cirrhosis, 23 patients with alcoholic cirrhosis and 12 healthy controls were submitted to measurement of left ventricular volumes, cardiac output, mean arterial pressure and total peripheral resistance. RESULTS Patients with cirrhosis showed a similar increase in cardiac index and heart rate and reduction of mean arterial pressure and peripheral vascular resistance in comparison to controls, irrespective of the aetiology. Left ventricular end systolic volume index was lower (p<0.01) and ejection fraction higher (p<0.01) in virus-related cirrhotic patients [mean +/- SD, respectively 12.4+/-4.1 ml/sqm and 77.9%) in comparison both to controls (21.5+/-6.3 ml/sqm and 66.8%) and alcoholics (20.6+/-7.0 ml/sqm and 68.8%). End diastolic volume index was not significantly different between the three groups. CONCLUSIONS Our findings indicate smaller left ventricular volumes and higher ejection fraction in pure virus-related cirrhosis than in alcoholic cirrhosis and controls. Since peripheral haemodynamics proved similar in virus- and alcohol-related cirrhosis, a subclinical alcohol cardiomyopathy may be hypothesised to account for the absence of such left ventricular pattern in alcoholic patients.

A case of extracranial vertebral artery dissection with spontaneous recovery: Diagnosis and follow-up by duplex and color Doppler

A 47-year-old women developed an acute vestibular syndrome with a peripheral facial palsy not associated with any trauma. Magnetic resonance imaging showed an ischemic lesion in the territory of the posterior inferior cerebellar artery. Color Doppler ultrasonography detected an occlusion of the right vertebral artery and dissection of the artery was confirmed by a subsequent angiography. During follow-up Duplex-Doppler allowed a non-invasive monitoring of recanalization of the occluded artery. Copyright 1997 Elsevier Science Ireland Ltd.