Hepatorenal syndrome. New perspectives in pathogenesis and treatment.

Hepatorenal syndrome is a life-threatening complication of severe liver disease. It is generally accepted that the syndrome is the final stage of complex hemodynamic derangements associated with portal hypertension, ie, peripheral arterial vasodilation, effective hypovolemia, and hyperkinetic status. In spite of reduced systemic resistances, intrarenal vascular resistances are increased. This is probably the consequence of the activation of systemic vasoactive factors, such as the renin-angiotensin system, the sympathetic nervous system, and vasopressin aimed at restoring arterial filling pressure. Recently, it has been shown that intrarenal vasoconstrictors, such as leukotrienes and endothelins, are activated with the progression of liver disease. The renal vasoconstriction is counterbalanced by the intrarenal hyperproduction of vasodilating prostaglandins and kallikreins. When this balance is lost, for whatever mechanism, the renal vascular resistances dramatically increase and the hepatorenal syndrome develops. In spite of increased knowledge about pathogenesis, the treatment of hepatorenal syndrome remains unresolved. Low-dose dopamine or ornipressin are currently employed in many liver units to avoid further deterioration of renal function in patients with severe liver disease who are waiting for liver transplantation that remains, at present, the only effective treatment for hepatorenal syndrome.

Renal and humoral effects of ibopamine, a dopamine agonist, in patients with liver cirrhosis.

We investigated the renal and humoral effects of short-term administration of ibopamine, an orally active dopamine agonist, in patients with liver cirrhosis. The patients were divided into two groups on the basis of sodium excretion with a constant sodium intake of 40 mEq/d. We also compared the effects of ibopamine with those induced by intravenous infusion of dopamine hydrochloride (3 micrograms/kg per minute) in similar patients. Ibopamine caused significant increases in urine output, glomerular filtration rate, and sodium excretion throughout the 4 hours of the trial in patients with basal sodium excretion rate greater than 20 mmol/d. These renal effects were associated with a significant reduction in plasma aldosterone concentration. In contrast, only a transient increase in glomerular filtration rate and a diminution in plasma aldosterone concentration were observed after ibopamine in the patients with a basal sodium excretion rate less than 20 mmol/d. The infusion of dopamine had renal effects similar to those of ibopamine in both groups of patients. These results indicate that in cirrhotic patients with normal sodium excretion, ibopamine exerts a diuretic and natriuretic effect similar to that of dopamine infusion. However, these properties of dopaminergic agents are apparently lost in patients with avid sodium retention.

Vertebral osteopenia due to bone marrow hyperplasia during interferon-alpha and ribavirin therapy for chronic hepatitis C.

We report the magnetic resonance imaging of a severe, but fully reversible, vertebral osteopenia, due to bone marrow hyperplasia, occurring in a patient with chronic hepatitis C treated with the interferon-alpha/ribavirin combination.

Benign and solid tumors of the liver: relationship to sex, age, size of tumors, and outcome.

From 1983 through 1997, our center diagnosed 130 cases of benign neoplasms: 27 with focal nodular hyperplasia (FNH), 25 with hepatic adenoma, 71 with cavernous hemangioma, and seven with mixed tumors of different diagnoses. Most often these lesions were seen in females [female-to-male ratio (f/m): 5.5/1]. Hepatic adenomas and mixed tumors were seen exclusively in females and FNH predominantly in females (f/m: 26/1). Hemangiomas, however, were not uncommon in men (f/m: 52/19) relative to the other tumors (P < 0.001). Furthermore patients with hemangioma were older (mean age: 49 years) whereas patients with hepatic adenoma, FNH, and mixed tumors were often younger (mean age: 33, 35, and 44 years respectively; P < 0.004). Oral contraceptive steroid use was related by 21 of 25 patients (84%) with hepatic adenoma, 22 of 26 (85%) females with FNH, five of seven (71%) females with mixed tumors, and 10 of 52 (19%) patients with hemangioma. Ninety-five of the 130 patients (73%) had one or more symptoms. There was no statistically significant correlation between symptoms and the size of the lesion, the final diagnosis, and whether there were solitary or multiple masses. Three of 25 (12%) with hepatic adenoma presented with rupture, and one of 27 (4%) with FNH had such a consequence. None of the hemangiomas presented with rupture or progressed to such a state. One patient with hepatic adenoma (4%) had a focus of malignancy. Surgical removal of benign tumors was performed in 82 of 130 patients (63%), and there was one operative mortality (1.2%) in a patient who had a caudate lobe FNH. The types of surgical procedures included segmentectomy (62%), lobectomy (34%), and trisegmentectomy (4%). In two of 84 patients who had undergone laparotomy resection was not technically possible. Resection is recommended in all cases of hepatic adenoma because of fear of rupture or associated focus of malignancy. FNH was not observed to undergo a malignant transformation and will rarely rupture. Surgery is only recommended for symptomatic hemangioma, and size of the lesion is not a criterion for excision.

Current practices regarding visitation policies in critical care units.

BACKGROUND: Previous research has emphasized the importance of visitation in critical care units and its beneficial effects on patients and their families. However, nurses' attitudes and beliefs about visitation did not correlate with those of patients and their families, nor did actual visitation practices correlate with written policy. OBJECTIVE: To investigate nurses' perceptions about open vs restricted visiting hours and the effects on the patient, the patient's family, and the nurse. METHODS: Quantitative and qualitative data were collected from 201 nurses who completed a survey instrument about nurses' perceptions of visitation at five metropolitan hospitals in a midwestern city. RESULTS: Seventy percent of official policies for visitation were restrictive. In practice, 78% of nurses were nonrestrictive in their visitation practices. Variables that affected practices regarding visiting hours were the patient's need for rest, the nurse's workload, and the beneficial effects of visitation on patients. Requests from patients and their families were ranked least important. Significant differences in practices were found regarding restriction of visiting by immediate family members and of the number of visitors. Restricted hours were perceived to decrease noise (83%) and promote patients' rest (85%). Open visitation practices were perceived to beneficially affect the patient (67%) and the patient's family (88%) and to decrease anxiety (64%). Perceptions of ideal visiting hours included restrictions on the number of visitors (75%), hours (57%), visits by children (55%), and duration of visits (54%), but no restriction on visitation by immediate family members (60%). Qualitative data revealed recurrent themes in visitation practices, policies and exceptions, control of visitation by patients, and nurses' wishes. CONCLUSION: Data indicate that most nurses do not restrict visitation, regardless of whether restrictive policies are in place. Most nurses base their visitation decisions on the needs of the patient and the nurse. Needs of the family were ranked as less important in decision making about family visitation.

Gitelman syndrome: pathophysiological and clinical aspects.

Giltelman syndrome (GS) is a recessive salt-losing tubulopathy of children or young adults caused by a mutation of genes encoding the human sodium chloride cotransporters and magnesium channels in the thiazide-sensitive segments of the distal convoluted tubule. The plasma biochemical picture is characterized by hypokalemia, hypomagnesemia, hypocalciuria, metabolic alkalosis and hypereninemic hyperaldosteronism. However, patients with GS present some clinical and biochemical alterations resembling that observed in thiazide diuretics abuse. On the pathophysiological point of view, GS represents a useful and interesting human model to better understand the clinical consequences of plasma hydro-electrolytes and acid-base derangements, associated with multiple hormonal alterations. The impact of this complex disorder involves cardiovascular, muscle-skeletal and some other physiological functions, adversely affecting the patient's quality of life. This review tries to summarize and better explain the linkage between the electrolytes, neurohormonal derangements and clinical picture. Moreover, the differential diagnosis between other similar electrolyte-induced clinical disorders and GS is also discussed.

Amebiasis.

More than 80% of cases of amebic liver abscess can be managed with a 14-day course of intravenous or oral metronidazole. In cases of suspected amebic liver abscess, treatment should be started before diagnostic confirmation. If no clinical improvement is evident by 72 to 96 hours, treatment should be changed to dehydroemetine and chloroquine. Invasive treatment is necessary only in patients in whom medical treatment fails within 5 days or in whom signs of clinically severe disease are present. A 10-day course with a luminal agent such as paromomycin to eliminate intestinal cysts, which are resistant to imidazoles, should always follow treatment of the liver abscess. Percutaneous catheter drainage is indicated in patients with impending rupture, with a lesion 6 cm or more in diameter, with an abscess located in the left lobe or high in the dome of the right lobe, or in whom medical treatment fails. Although sympathetic pleural effusion is not an indication for drainage, direct pulmonary involvement or spread to pleural or lung tissues requires drainage. Intraperitoneal rupture and peritonitis necessitate open surgical drainage. Only a small minority of amebic liver abscesses are secondarily infected by other organisms. Because relapses are possible, feces should be checked for cysts monthly for several months after therapy.

Atrial natriuretic factor in cirrhotic patients with tense ascites. Effect of large-volume paracentesis.

The plasma levels of atrial natriuretic factor in liver cirrhosis can be affected by various factors, such as ascites, renal function, use of diuretics drugs and dietary sodium intake. Moreover, the influence of high intra-abdominal pressure on cardiac atrial natriuretic factor release in patients with tense ascites has not been investigated. The aim of the present study was to evaluate the circulating levels of atrial natriuretic factor and their relationships to plasma renin activity, aldosterone concentration, and urinary sodium excretion in 45 cirrhotic patients divided into 4 groups: (a) cirrhotics without ascites; (b) nonazotemic cirrhotics with ascites; (c) cirrhotics with ascites and functional renal failure; and (d) cirrhotics with ascites taking diuretics. In some patients with tense ascites, atrial natriuretic factor was also measured after rapid abdominal relaxation by large volume paracentesis. Plasma levels of atrial natriuretic factor obtained in 13 healthy control subjects after 5 days on a 40-50 mEq sodium daily intake were 22.8 +/- 3.3 pg/ml. Mean plasma atrial natriuretic factor levels were normal in patients without ascites (35.1 +/- 11.4 pg/ml) and in those with ascites taking diuretics (27 +/- 9.2 pg/ml), but elevated in patients with ascites not taking diuretics (59.6 +/- 12 pg/ml) and in those with ascites and functional renal failure (58.5 +/- 16.6 pg/ml). These data show that plasma atrial natriuretic factor levels are elevated only in cirrhotic patients who are ascitic and not taking diuretics. In these patients atrial natriuretic factor levels were directly correlated with urinary sodium excretion, even though sodium balance was positive. This could be the consequence of the contrasting effects of antinatriuretic factors, as suggested by the inverse relationships between atrial natriuretic factor and urinary sodium on the one hand and plasma renin activity and plasma aldosterone concentration on the other. Twenty-six patients with tense ascites (12 taking diuretics and 14 not) were treated with rapid large-volume paracentesis (6500 +/- 330 ml of ascitic fluid removed in 168 +/- 16 min). At the end of the procedure, plasma atrial natriuretic factor levels had increased in all patients (from 45.5 +/- 10.1 to 100 +/- 17 pg/ml), whereas plasma renin activity and plasma aldosterone concentration had decreased (from 10.3 +/- 1.6 to 7 +/- 1.3 ng/ml/h, and 1160 +/- 197 to 781 +/- 155 pg/ml, respectively).(ABSTRACT TRUNCATED AT 400 WORDS)

Renal response to atrial natriuretic peptide in patients with advanced liver cirrhosis.

Sodium retention in liver cirrhosis is thought to be due to, among other things, lack of a natriuretic factor or failure to respond to one. alpha-Human-atrial natriuretic peptide is a peptide that accounts partly or entirely for the circulating natriuretic activity in man. In the present study, we have evaluated the effects of the bolus administration of synthetic alpha-human-atrial natriuretic peptide (1 microgram per kg) to patients with liver cirrhosis and variable degrees of sodium retention. alpha-Human-atrial natriuretic peptide induced rapid and marked increases of diuresis and natriuresis in patients without sodium retention or with moderate retention. The results were comparable to those obtained in six healthy control subjects. Conversely, the diuretic and natriuretic effects of alpha-human-atrial natriuretic peptide were attenuated or completely blunted in patients with avid sodium retention. The two groups of patients differed not only in basal sodium excretion, but also in plasma renin activity and in plasma aldosterone levels, suggesting that the reduced responsiveness to atrial natriuretic peptide might be due to excessive antagonism by antinatriuretic factors. The direct relationship between baseline sodium excretion rate and that stimulated by human-atrial natriuretic peptide administration was consistent with this interpretation. In none of the subjects did plasma renin activity peptide and cortisol levels change after human-atrial natriuretic peptide, while plasma aldosterone slightly declined in cirrhotics. Blood pressure fell after the administration of the peptide, with the drug greater in cirrhotic than in normal subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Paracentesis: a re-evaluated procedure in the management of cirrhotic patients with ascites.

Paracentesis is the oldest method for treating patients with ascites, but the fear of serious side-effects and the coincident introduction of effective non-toxic diuretic drugs led to its abandonment during the fifties. In recent years, several studies have investigated whether abdominal evacuation of ascitic fluid is truly dangerous for cirrhotic patients. The results of some randomized controlled trials comparing paracentesis with a traditional diuretic therapy showed that the rate of complications after paracentesis, particularly when the procedure was combined with a sufficient plasma expansion, was equal to or lower than that of diuretic treatment. Moreover, the ability of paracentesis to resolve tense ascites, both in terms of number of successes and of time required to obtain ascites resolution, was similar or even higher. These data and the recent new interest of several investigators in employing ascitic fluid examination for diagnostic purposes have increased the use of this procedure in the clinical practice.

Renal effects in cirrhotic patients with avid sodium retention of atrial natriuretic factor injection during norepinephrine infusion.

The administration of atrial natriuretic factor to patients with cirrhosis, and avid sodium retention causes marked hypotension and blunted kidney responses. To evaluate whether the unresponsiveness of the kidney is caused by a fall in mean blood pressure below a critical value for the renal blood perfusion pressure (80 mm Hg), we studied nine such patients and compared the effects of synthetic atrial natriuretic factor alone (1 micrograms/kg as a bolus) with those of an atrial natriuretic factor combination with infused norepinephrine titrated to raise baseline blood pressure by 15 to 20 mm Hg (182 to 625 ng/kg/min). The administration of atrial natriuretic factor during norepinephrine infusion caused a fall in mean blood pressure to values not less than 80 mm Hg in eight of nine patients, with a slight natriuresis (greater than 5 mumol/min) in five patients but no changes in the other four. The mean urinary sodium output was markedly lower than that previously observed after atrial natriuretic factor injection into normal subjects and into cirrhotic patients without avid sodium retention. Unlike sodium excretion, urine flow rate and free water clearance (which were not affected by atrial natriuretic factor alone) were markedly improved by the coadministration of norepinephrine and atrial natriuretic factor. In four additional patients we studied the urinary electrolyte excretion during a low-dose infusion of atrial natriuretic factor (20 ng/kg/min) to which an infusion of norepinephrine titrated to maintain blood pressure over 80 mm Hg was added. In only one of these four patients urinary sodium output consistently increased during atrial natriuretic factor infusion, and the output increased even more when norepinephrine was added.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal effects of imidazole-2-hydroxybenzoate in patients with compensated liver cirrhosis.

A double-blind crossover study versus placebo of the renal effects of the nonsteroidal anti-inflammatory drug imidazole 2-hydroxybenzoate was conducted in 10 patients with compensated liver cirrhosis. The administration of the drug (750 mg, t.i.d., for three days) did not affect renal plasma flow, glomerular filtration rate, free water clearance nor the urinary excretion of sodium or potassium. Values of plasma renin activity also did not change after drug administration. Direct tubular damage from imidazole 2-hydroxybenzoate was also excluded by normal excretion of beta-2-microglobulin and N-acetyl-beta-D-glucosaminidase. Urinary 6-keto-PGF1 alpha output were comparable during imidazole 2-hydroxybenzoate and placebo administration. These data indicate that this nonsteroidal antiinflammatory drug does not affect the renal function in patients with compensated liver cirrhosis.

Randomized comparative study of hemaccel vs. albumin infusion after total paracentesis in cirrhotic patients with refractory ascites.

Fifty-four cirrhotic patients with refractory ascites were treated with one-session large-volume paracentesis and randomly assigned to two groups. The first group was infused with human albumin, and the second group was infused with hemaccel at doses with comparable oncotic power. The two groups were compared for incidence of complications, recurrence of massive ascites after hospital dismissal and survival rate. The incidence of complications traditionally related to paracentesis, the probability of requiring readmission to the hospital for ascites (p = 0.48) and the probability of survival after entry into the study (p = 0.85) were the same for the two groups. A multivariate analysis of 16 parameters, including treatment modality, identified absolute unresponsiveness to diuretics as the only independent predictor of mortality. These results indicate that hemaccel infusion may safely replace albumin infusion after total paracentesis for cirrhotic patients with refractory ascites.

Single-tube reverse transcription and heminested polymerase chain reaction of hepatitis C virus RNA to detect viremia in serologically negative hemodialysis patients.

Detection of hepatitis C virus genome is the only method currently available for detecting viremia in infected individuals. We describe a substantial simplification of current methods for viral RNA reverse transcription and polymerase chain reaction amplification, which allows cDNA synthesis and nested amplification in a single tube; this is achieved through compartmentalization of the reagents for the two reactions with a wax barrier. This procedure retains a high sensitivity: analysis of serum samples from hemodialysis patients, a high-risk group for hepatitis C virus infection, confirmed the presence of the virus in 88% of antibody-positive patients and detected viremia in patients without serological or biochemical evidence of hepatitis C virus infection.

Effects of imidazole-salicylate on renal function and the diuretic action of furosemide in cirrhotic patients with ascites.

Imidazole-salicylate is a non-steroidal anti-inflammatory drug with limited inhibitory effects on prostaglandin synthesis. The renal effects of this drug were investigated by a double-blind cross-over study in 10 patients with cirrhosis and ascites. Two therapeutic doses of imidazole-salicylate (750 mg each) were given at midnight and 08:00 h and 80 mg of furosemide were injected intravenously at 09:00 h. The same procedure was followed on another day but a placebo replaced imidazole-salicylate. Renal function (creatinine clearance, free water and electrolyte excretions) and urinary excretion of prostaglandin E, 6-keto-prostaglandin F1 alpha and thromboxane B2 were evaluated for 8 h after the first dose of the drug and for 2 h after furosemide injection. Platelet thromboxane production was also determined 9 h after the first administration of drug or placebo. Imidazole-salicylate did not affect renal function or inhibit kidney prostanoid production either under basal conditions or after the stimulating effect of furosemide. On the contrary, imidazole-salicylate significantly inhibited platelet thromboxane production (45.8 +/- 9 vs. 69.4 +/- 7.5 ng/ml, P < 0.05). These results suggest that imidazole-salicylate is an anti-inflammatory drug that can be given to patients with decompensated cirrhosis without risk of inhibiting kidney prostaglandin synthesis or the renal response to furosemide.

Validation study of thoracic fluid bioimpedance for assessing the haemodialysis-induced changes in total body fluids.

Thoracic fluid bioimpedance (TFB) has been proposed as a noninvasive technique for monitoring both haemodynamics and fluid homeostasis in patients on regular dialysis. To validate the reliability of TFB in assessing the haemodialysis (HD)-induced changes in plasma volume (PV) in these patients, we examined the changes of TFB during and after HD in relation to those in total plasma protein (TP) concentration, haematocrit (Ht), heart rate (HR), total body water (TBW) and plasma angiotensin II (A-II) concentration. Data were recorded in 13 HD patients with a wide range of interdialytic weight gains before, at the end, and 4, 8, 24, 48 h after the HD session. We found that the percent TFB changes were closely and inversely related with those of TP, Ht and TBW (r = -0.54, r = -0.45 and -0.68, respectively, p < 0.001 for all). Similar relations were found between the percent changes in TFB and those in absolute TP and Ht. In addition, a direct relation was found between the percent changes of TFB and those of HR and of A-II (r = 0.33 and r = 0.31, respectively, p < 0.01 for both). These data indicate that TFB is a reliable method for evaluating the HD-induced changes of intra- and extravascular fluids and, with respect to the conventional techniques, has the advantage of providing this information dynamically, and in conjunction with the haemodynamic data of patients.