Role of functional polymorphisms of NRAMP1 gene for the development of Crohn's disease.

BACKGROUND: Crohn's disease (CD) is characterized by chronic activation of macrophages. Natural resistance-associated macrophage protein 1 (NRAMP1) gene exerts many pleiotropic effects on macrophage functions. Hence, NRAMP1 may be also involved in the resistance to intracellular pathogens, and this effector of the innate immunity might be involved in CD pathogenesis. Polymorphic alleles at the NRAMP1 locus have been previously associated with susceptibility both to the putative infectious agents and to autoimmune disorders. Based on these indications, in the present study we investigate its candidacy as a genetic determinant for CD in a Greek population in an association-based study, comparing frequencies of 274 CD patients to these of 200 healthy control subjects. METHODS: The 5'(GT)n promoter polymorphism and 9 either single nucleotide (SNPs) or insertion/deletion type polymorphisms were genotyped across the NRAMP1 gene. Reverse-transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry were performed in order to investigate the NRAMP1 mRNA levels in RNA isolated from biopsies of CD patients as well as protein expression in tissues. RESULTS: Three NRAMP1 polymorphisms [5'(GT)n, D543N, and INT4G/C] were significantly associated with CD. Consistent with previous autoimmune disease studies, allele 3 at the functional 5'(GT)n promoter region repeat polymorphism, was significantly associated with CD when compared to healthy controls (odds ratio 1.50; 95% confidence interval [CI]: 1.16-1.95; P = 0.002). Interestingly, we observed that CD patients homozygous for allele 3 expressed higher NRAMP1 mRNA levels compared to carriers of allele 2. Furthermore, the protein levels of allele 3 carriers in tissues were also elevated compared to those of allele 2 carriers. Based on these data we can speculate that overrepresentation of allele 3 in CD patients could lead to hyperactivation of bowel-wall macrophages that are chronically exposed to lipopolysaccharide and this could subsequently cause the autoimmune-like phenotype characteristic of CD. CONCLUSIONS: Collectively, our data indicate that genetic polymorphisms of NRAMP1 might be associated with susceptibility to CD.

Effects of a 7-day treatment with midodrine in non-azotemic cirrhotic patients with and without ascites.

BACKGROUND/AIMS: Splanchnic arterial vasodilatation has been causally related with hyperdynamic circulation and impaired natriuresis in advanced cirrhosis and has also been suggested to be responsible for the subtle sodium retention in pre-ascitic cirrhosis. This study evaluated the effects of a 7-day treatment with the alpha1-adrenergic agonist midodrine in non-azotemic cirrhotic patients with and without ascites. METHODS: Thirty-nine cirrhotic patients were studied at baseline and 7 days after administration of oral midodrine 10mg, t.i.d. (11 without and 12 with ascites) or placebo (8 without and 8 with ascites). RESULTS: A significant increase in urine sodium excretion was noted after midodrine administration in patients without and with ascites, in line with significant increases in mean arterial pressure and systemic vascular resistance, and significant decreases in cardiac output and heart rate. Significant increases in glomerular filtration rate, filtration fraction, and urine volume and significant decreases in plasma renin activity and aldosterone were observed in patients with ascites. Placebo had no effect in any study group. CONCLUSIONS: The administration of midodrine for 7 days improves systemic haemodynamics and sodium excretion in non-azotemic cirrhotic patients without or with ascites. In patients with ascites, but not in those without ascites, these effects are associated with a suppression of the activity of the renin-angiotensin-aldosterone system, suggesting that the increase in natriuresis is related to the improvement in the effective arterial blood volume.

A single alcohol ingestion does not affect serum hepatitis C virus RNA in patients with chronic hepatitis C.

BACKGROUND AND AIM: The safe level of alcohol ingestion in sporadic drinkers with hepatitis C is unknown. Our aim was to evaluate the effect of a single moderate alcohol intake on serum HCV RNA concentrations and hepatic function in patients with chronic HCV infection. METHODS: Twenty-one patients with chronic hepatitis C were randomly assigned to consume 50 g alcohol (group 1) or a non-alcoholic beverage (group 2). In both groups, serum ethanol, serum HCV RNA, transaminase and gamma-glutamyltranspeptidase (gamma-GT) levels were measured just before alcohol intake and after 1, 2, 8, 24 h and 1 week's time. RESULTS: The maximum concentration of ethanol in the blood was observed at the first hour after alcohol intake. No significant changes were observed in serum HCV RNA after alcohol intake. Repeated measurements of HCV RNA among the two groups revealed no difference (P = 0.215). Similarly, no difference was observed in transaminase and gamma-GT levels at different time points in each group or among the groups [(ALT (P = 0.082), AST (P = 0.33), gamma-GT (P = 0.538)]. CONCLUSIONS: In patients with chronic hepatitis C, a single intake of 50 g alcohol does not affect liver biochemistry and HCV RNA concentrations. Therefore, it is a matter of further research whether sporadic drinking of light or moderate amounts of alcohol should be avoided in patients with chronic hepatitis C.

The effects of treatment with octreotide, diuretics, or both on portal hemodynamics in nonazotemic cirrhotic patients with ascites.

GOALS: To evaluate the effects of diuretic treatment, octreotide, or both on portal hemodynamics in nonazotemic cirrhotic patients with ascites. BACKGROUND: Diuretics and octreotide have been associated with a decrease in portal pressure in cirrhotic patients, suggested to be mediated by plasma volume depletion and splanchnic vasoconstriction, respectively. However, liver cirrhosis is characterized by activation of the renin-angiotensin-aldosterone axis, which increases hepatic vascular resistance and is augmented or suppressed by diuretics or octreotide, respectively. STUDY: Twenty nonazotemic cirrhotic patients with ascites were treated with furosemide and spironolactone. Of them, 10 (group 1) discontinued diuretic treatment for 7 days. Thereafter for 5 days, each patient received subcutaneous octreotide, 300 microg twice per day; ten of them (group 2) received the octreotide in addition to their usual diuretic treatment. Portal and systemic hemodynamics with Doppler ultrasound and endogenous vasoactive systems were evaluated while the patients received diuretics (both groups), after discontinuation of diuretics (group 1), and after octreotide administration (both groups). RESULTS: The withdrawal of diuretics did not alter portal hemodynamics, but it impaired systemic hemodynamics and suppressed the renin-aldosterone axis. The addition of octreotide to diuretic treatment but not octreotide alone improved portal and systemic hemodynamics. In both groups the initiation of octreotide administration suppressed the renin-aldosterone axis and plasma glucagon levels. CONCLUSIONS: In nonazotemic cirrhotic patients with ascites, the combination of diuretics and octreotide improves systemic hemodynamics and inhibits the diuretic-related component of the activated renin-aldosterone axis, which in turn augments the portal hypotensive effect of diuretic-induced plasma volume depletion.

Interferon-alpha plus lamivudine vs lamivudine reduces breakthroughs, but does not affect sustained response in HBeAg negative chronic hepatitis B.

AIM: The HBeAg negative form of chronic hepatitis B (CHB) predominates in the Mediterranean area and has a rising frequency in Europe and North America. At present there are three approved therapies for patients with CHB: interferon-alpha (IFN-alpha), lamivudine and adefovir dipivoxil. Unfortunately, none of these drugs are effective in achieving a sustained response in patients with HBeAg negative CHB. Therefore, new therapeutic approaches have been examined. Our aim was to investigate the efficacy of combination treatment of IFN-alpha and lamivudine compared to lamivudine monotherapy, after 24 mo of administration in HBeAg-negative hepatitis B patients. METHODS: Fifty consecutive patients were randomly assigned to receive IFN-alpha-2b (5 MU thrice per week, n = 24) plus lamivudine (100 mg daily) or lamivudine only (n = 26) for 24 mo. Patients were followed up for further 6 mo. The primary outcome was the proportion with sustained virological response (undetectable serum HBV DNA concentrations) and or sustained biochemical response (transaminase levels within normal range) at 30 mo (6 mo after the end of therapy). Secondary end-points were timed from initial virological (biochemical) response to VBR (BBR, respectively) and the emergence of YMDD mutants across the two arms. RESULTS: Five of twenty-four (21%) patients in the combination arm vs 3/26 (12%) in the lamivudine arm had sustained response (i.e., normal serum transaminase levels and undetectable HBV DNA by PCR assay) 6 mo after treatment discontinuation. A reduction in the emergence of YMDD mutants and in the development of virological breakthroughs was observed in patients receiving combination treatment (10% vs 46%, P = 0.01 and 14% vs 46%, P = 0.03, respectively). Time from initial virologic response to virologic breakthrough (VBR) was greater among initial responders receiving combination treatment compared to those receiving lamivudine (22.9 mo vs 15.9 mo, respectively; P = 0.005). CONCLUSION: Our results demonstrate that IFN-alpha plus lamivudine combination therapy did not increase the sustained response, compared to lamivudine. However, combination therapy reduces the likelihood of VBR due to YMDD mutants and prolongs the time period until the breakthrough development.

Effects of nitric oxide inhibition by methylene blue in cirrhotic patients with ascites.

Increased endogenous nitric oxide production has been proposed as an important mediator of the peripheral arterial vasodilation and the hyperdynamic circulation in cirrhosis, whereas a decreased intrahepatic production of nitric oxide has been implicated in the pathogenesis of portal hypertension. The present study investigated the possible beneficial effects of methylene blue, which is a potent inhibitor of guanylate cyclase and nitric oxide synthase, on hyperdynamic circulation and renal function in cirrhotic patients with ascites together with the effects on portal hemodynamics. Twenty patients were evaluated at baseline and during 2 consecutive 4-hr periods after the administration of methylene blue at a dose of 3 mg/kg (10 patients) or placebo (10 patients). Mean arterial pressure, heart rate, cardiac output, systemic vascular resistance, plasma active renin, plasma aldosterone, plasma antidiuretic hormone, serum urea, serum creatinine, serum sodium, urinary flow rate, glomerular filtration rate, effective renal plasma flow, portal flow volume, and portal vein velocity were not modified by methylene blue or placebo. Urinary sodium excretion, fractional sodium excretion and serum nitric oxide levels were significantly decreased 4 hr after methylene blue administration (P < 0.05), to return toward basal levels over a further 4-hr period. It is concluded that methylene blue, at the dose used in the present study, has no effect on systemic and portal hemodynamics in cirrhotic patients with ascites. The reduction in renal sodium excretion, in the absence of changes in renal function and hemodynamics, suggests, at least partly, a direct antinatriuretic effect of methylene blue.

Effects of somatostatin, terlipressin and somatostatin plus terlipressin on portal and systemic hemodynamics and renal sodium excretion in patients with cirrhosis.

BACKGROUND AND AIM: Terlipressin and somatostatin are the most preferable agents for the control of variceal bleeding in cirrhotic patients. The present study evaluated the hemodynamic effects of somatostatin, terlipressin and somatostatin plus terlipressin in cirrhotic patients with portal hypertension, as well as the effect of each regimen on renal sodium excretion. METHODS: Twenty-four patients with esophageal varices were randomly assigned to receive either an intravenous infusion of a placebo (n = 12) or somatostatin 250 microg/h after an initial bolus of 250 microg (n = 12) for 60 min. Thereafter, each patient received an intravenous injection of terlipressin 2 mg while the intravenous infusion of either somatostatin or placebo was maintained. Portal and systemic hemodynamic parameters, assessed by Doppler sonography, and urinary sodium excretion were evaluated at baseline, 60 min after placebo or somatostatin, and 30 min after terlipressin. RESULTS: Placebo had no effect on the patients studied. After terlipressin, portal vein velocity, portal flow volume and cardiac output (CO) significantly decreased (0.09 vs 0.15 m/s, 0.56 vs 1 L/min and 6.4 vs 7.6 L/min, respectively [values are medians]), while mean arterial pressure (MAP) and systemic vascular resistance significantly increased (103.3 vs 89.9 mmHg and 1541 vs 1108dyn.s/cm(5), respectively). Fractional sodium excretion significantly increased in patients without ascites (0.43 vs 0.16%) while it did not change in patients with ascites. Somatostatin did not alter portal hemodynamics whereas it significantly reduced MAP, heart rate (HR) and CO (86.9 vs 98.6 mmHg, 65 vs 73 bpm and 8.4 vs 9.1 L/min, respectively) and, in patients with ascites, sodium excretion (0.13 vs 0.23%). The addition of terlipressin to somatostatin induced similar changes to those observed after terlipressin alone. The magnitude of increase in MAP was significantly higher in patients receiving terlipressin alone than in those receiving somatostatin plus terlipressin (15 vs 5.3%), while CO was conversely affected (-28.5 vs-20.9%). CONCLUSIONS: Combined treatment with somatostatin and terlipressin does not exert an additive portal hypotensive effect in cirrhotic patients as compared to terlipressin alone, whereas somatostatin alone may impair systemic hemodynamics. Compared with somatostatin, terlipressin exerts a more beneficial effect on renal sodium excretion in patients with or without ascites.

Renal effects of treatment with diuretics, octreotide or both, in non-azotemic cirrhotic patients with ascites.

BACKGROUND: Diuretic-induced hyperreninaemia is associated with renal dysfunction in cirrhotic patients with ascites, and in turn prevents the use of high doses of diuretics. Furthermore, ample evidence suggests that octreotide can inhibit the activation of the renin-aldosterone axis. The present study investigated the renal effects of the addition of octreotide to furosemide and spironolactone in the treatment of non-azotemic cirrhotic patients with ascites. METHODS: We studied 20 patients treated with furosemide and spironolactone. Of them, 10 (Group 1) discontinued diuretic treatment for 7 days. Thereafter, for 5 days each patient received subcutaneous octreotide 300 microg b.i.d., in 10 patients (Group 2) in addition to their usual diuretics. We collected data on the patients while they received diuretics (both groups), after discontinuation of diuretics (Group 1), and after octreotide administration (both groups). RESULTS: We observed a trend to increase creatinine clearance and a significant reduction in plasma active renin and plasma aldosterone after the discontinuation of diuretics. The subsequent introduction of octreotide reduced glomerular filtration rate, although it significantly decreased plasma active renin and plasma aldosterone. In contrast, the addition of octreotide to diuretic treatment significantly increased glomerular filtration rate, urine volume and sodium excretion. The magnitudes of the decreases in plasma-active renin and aldosterone produced by the combination of octreotide and diuretics were similar to those produced by octreotide alone or by the discontinuation of diuretics. CONCLUSIONS: Octreotide alone does not improve renal function in cirrhotic patients with ascites. On the contrary, adding it to diuretic treatment increases glomerular filtration rate and sodium and water excretion, mainly through the suppression of an activated renin-aldosterone axis.

The effects of chronic treatment with octreotide versus octreotide plus midodrine on systemic hemodynamics and renal hemodynamics and function in nonazotemic cirrhotic patients with ascites.

OBJECTIVES: The adrenergic agonist midodrine improved circulatory and renal dysfunction when acutely administered in nonazotemic cirrhotic patients with ascites while its combination with octreotide has recently been proposed as an effective treatment of type 1 hepatorenal syndrome (HRS). However, the effects of octreotide on systemic hemodynamics and renal function in cirrhotic patients are controversial. This study evaluated the effects of chronic treatment with octreotide versus octreotide plus midodrine on systemic hemodynamics and renal hemodynamics, and function in nonazotemic cirrhotic patients with ascites. METHODS: Twenty-five patients were studied at baseline and 11 days after administration of subcutaneous octreotide 300 mug, b.i.d. alone (n = 12) or together with oral midodrine 7.5 mg, t.i.d. (n = 13). RESULTS: Octreotide did not improve systemic hemodynamics whereas the addition of midodrine significantly decreased cardiac index (CI) and heart rate (HR), and increased mean arterial pressure (MAP) and systemic vascular resistance (SVR). Octreotide caused a decrease in renal vascular resistance (RVR) and increased renal blood flow (RBF) but significantly reduced glomerular filtration rate. The association of midodrine to octreotide did not modify renal hemodynamics and function as compared to baseline while it caused an almost significant minor increase in RVR and a significant minor decrease in RBF as compared to octreotide alone. Consequently, a significant minor increase in glomerular filtration rate was demonstrated. The plasma values of active renin, aldosterone, and glucagon were significantly reduced in either group. CONCLUSIONS: Octreotide does not improve systemic hemodynamics in nonazotemic cirrhotic patients with ascites while it impairs renal function. On the other hand, the addition of midodrine can ameliorate the hyperdynamic circulation without inducing renal dysfunction in these patients.

Clinical course of lamivudine monotherapy in patients with decompensated cirrhosis due to HBeAg negative chronic HBV infection.

OBJECTIVES: We have evaluated the efficacy of long-term lamivudine monotherapy in patients with decompensated HBeAg-negative/HBV-DNA positive cirrhosis. METHODS: We analyzed the clinical course and outcome of lamivudine treatment in 30 consecutive cirrhotics and compared with 30 HBV untreated historical HBeAg-negative controls matched for age and gender. RESULTS: Significant clinical improvement, defined as a reduction of at least two points in Child-Pugh score was observed in 23 of the 30 treated patients (76.6%) versus none of the 30 patients in the control group (p < 0.0001) after a mean follow-up of 20.6 +/- 12.1(+/-SD) months. There were 10 deaths in the treated group versus 24 in the control group (p= 0.07). Liver-related deaths occurred in five of the eight patients soon after the development of biochemical breakthrough. Patients with clinical improvement had better survival than patients with no improvement (p= 0.04) or those who developed biochemical breakthrough due to YMDD mutants (p= 0.001). CONCLUSIONS: Lamivudine significantly improves liver function in HBeAg-negative decompensated cirrhosis. However, the development of the biochemical breakthrough due to YMDD mutants is associated with fatal outcome.