Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Renin-angiotensin system plays a prominent role in the sodium and water homeostasis. In addition, activation of renin-angiotensin system frequently occurs in patients with cirrhosis and ascites. Theoretically, administering of angiotensin converting enzyme inhibitors can enhance sodium and water retention in cirrhotic patients with ascites. In this study, we evaluate the role of low-dose captopril on renal function changes, renal plasma flow and hemodynamics in patients with cirrhosis and ascites. Fifty patients are randomly assigned to receive captopril or placebo for 14 days. Renal functions, renal plasma flow, plasma renin activity, plasma aldosterone concentration and systemic and hepatic hemodynamics are measured before and after treatment. Our results indicate that placebo administration did not affect any of the parameter measured in this study. The finding that low-dose captopril significantly increases plasma renin activity suggests that the dose used in this study effectively blocks the enzyme activity. However, low-dose captopril does not affect renal plasma flow, renal functions and systemic and hepatic hemodynamics. Results in this study demonstrate that inhibition of angiotensin converting enzyme alone may not improve sodium and water retention in cirrhotic patients with ascites.
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PMID:Effects of captopril on renal functions, renal and portal hemodynamics in patients with cirrhosis. 893 43

Diagnosis of liver cirrhosis relies on hepatic biopsy. So far, attempts have failed to achieve a serologic test that differentiates cirrhosis from other hepatic conditions. The aim of this work was to assess the diagnostic value of the ratio of serum angiotensin converting enzyme activity (SACE) and the levels of protein C4 of serum complement (SACE/C4) in differentiating cirrhotic from noncirrhotic alcoholic liver diseases. In this study, 68 active alcoholic patients (17 with fatty liver or minimal changes, 11 with acute alcoholic hepatitis and 40 with cirrhosis) were included. Twenty healthy subjects were studied as a control group. Liver biopsy was performed in all patients. SACE levels were significantly higher in the group with cirrhosis when compared with the group of patients without cirrhosis and the control. On the other hand, serum C4 level decreased as liver damage progressed. SACE values above 25 IU/l had a sensitivity of 92.5 percent (95 percent confidence interval, 87.5 to 97.5) and a specificity of 79 percent (95% percent confidence interval, 70.5 to 87.5), in detecting those patients with liver cirrhosis. The sensitivity further increased to 95 percent (95 percent confidence interval, 90.5 to 99.5) and the specificity to 100 percent when the SACE/C4 ratio was used and a cutoff point of 145 was chosen. To conclude, in alcoholics SACE is specifically elevated in patients with cirrhosis, and the SACE/C4 ratio is a excellent biochemical index for the diagnosis of cirrhosis in alcoholic patients.
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PMID:Serum angiotensin converting enzyme and C4 protein of complement as a combined diagnostic index in alcoholic liver disease. 893 30

In an open trial, the pharmacokinetics of the angiotensin converting enzyme inhibitor ramipril and its active metabolite ramiprilat were studied in 12 patients with liver cirrhosis. After a single oral dose of 5 mg ramipril plasma levels of the parent compound reached peak concentrations of 48.6 +/- 39.8 ng/ml after 0.7 +/- 0.5 h and declined rapidly to 0.7 +/- 1.2 ng/ml after 8 h. Plasma levels of ramiprilat reached peak concentrations of 3.8 +/- 2.9 ng/ml after 3.0 +/- 2.2 h, thereafter declined slowly and could be detected up to 240 h. The total recovery of ramipril and metabolites in urine within 96 h was on average 46.0 +/- 10.9% of the administered dose. Major fractions were due to diketopiperazines and glucuronides of ramipril and ramiprilat. The overall ACE inhibition was still 92.0 +/- 8.6%. In conclusion, patients with liver cirrhosis had enough capacity to metabolize and excrete the parent compound ramipril, but had not enough capacity to form ramiprilat, although enough ramiprilat was formed for sufficient ACE inhibition of about 90%. This indicates that titration of the dose should start with 5 mg or even lower doses in patients with markedly impaired liver function.
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PMID:Angiotensin-converting enzyme inhibition in cirrhotic patients--pharmacokinetics of ramipril. 915 Aug 5

Cirrhosis encompasses a range of pathophysiological changes that may alter drug disposition. Drugs that are dependent primarily on the liver for their systemic clearance are more likely to be subject to reduced elimination and subsequent accumulation. Drug accumulation may lead to excessive plasma drug concentrations and adverse effects, if the adverse effects of the drug are concentration-dependent. The effects of hepatic insufficiency on the pharmacokinetics of drugs are not consistent or predictable. Furthermore, the influence of hepatic disease on the disposition of various drugs can vary, even though those drugs may share the same apparent metabolic pathway. Problems in forecasting drug kinetic behaviour are further enhanced by the additional impairment of kidney function (frequently encountered in patients with advanced liver disease) and by the unpredictability of the glomerular filtration rate using customary methods in patients with cirrhosis. Accordingly, dosages are generally adapted empirically, with the help of serum drug concentrations, when applicable. However, drugs eliminated predominantly by hepatic metabolism are not among those most commonly inducing adverse drug reactions or causing severe complications in patients with cirrhosis. Electrolyte disturbances and the hepatorenal syndrome produced by furosemide (frusemide)-the disposition of which is not substantially modified in liver disease-appear to be the most frequent adverse drug reactions in patients with liver disease. Furthermore, clinically significant alterations in the action of medications at concentrations generally considered to be in the normal therapeutic range are not uncommon. Tissue responsiveness to the pharmacological action of some drugs may be modified, as evidenced by the increased susceptibility of the brain in patients with cirrhosis to the action of many psychoactive agents. Another example is the greater susceptibility of such patients to the nephrotoxic potential of aminogly-cosides, which should not be used in this patient group. Drugs may also interfere with adaptive physiological processes induced by liver disease. ACE inhibitors and nonsteroidal anti-inflammatory drugs counteract the enhanced activity of the renin-angiotensin system in advanced liver disease, thereby generating a high risk of excessive hypotension or acute renal failure, respectively. These drugs are best avoided in patients with cirrhosis. Finally, there may be pharmacological effects that overlap with some pathophysiological modifications related to the process of liver disease, such as increased portal pressure produced by some calcium antagonists, or hypoprothrombinaemia related to the inhibition of synthesis of vitamin K-dependent clotting factors by some beta-lactam antibacterials (especially moxalactam and cefamandole). Accordingly, the use of these drugs should be avoided in advanced liver disease. It is noteworthy that reduced drug metabolism in patients with liver disease does not seem to have a significant impact on the frequency of hepatotoxicity. Special caution should be exercised, however, in patients with alcoholic liver disease because excessive alcohol intake may potentiate the hepatotoxic effect of paracetamol (acetaminophen).
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PMID:Drug administration in chronic liver disease. 925 30

A posthepatitic cirrhotic patient may undergo elective or urgent abdominal operation for an extra-hepatic or hepatic disease. According to the high postoperative morbidity (61%), surgery is indicated only for symptomatic or complicated cholelithiasis. A surgical procedure for refractory ascites has been devised to create a permanent peritoneo-venous shunt by a one way pressure-sensitive valve (Leveen). The procedure is simple and brings a long lasting relief with recovery in strength and nutrition and improved kidney function. Sclerotherapy is widely used to treat acute variceal bleeding while repeated sclerotherapy is used in the long-term management to eradicate varices. When indicated, liver transplantation is the best treatment to prevent variceal bleeding recurrence. Also portosystemic shunts effectively prevent recurrent variceal bleeding. They are, however, major operations with an important morbidity and mortality, particularly in poor risk patients. The most advocated shunts today are the Warren distal splenorenal shunt and the Sarfeh portacaval shunt using a small diameter prosthetic H-graft. The transjugular intrahepatic portosystemic stent-shunt (TIPSS) is a new treatment for portal hypertension and its complications. From a haemodynamic point of view it allows balanced hepatic perfusion. Postoperative mortality is rare; further bleeding and encephalopathy are reasonably acceptable. The most relevant complications concern dislocation of the prosthesis, stenosis and thrombosis of the shunt, which can be corrected by non-invasive dilatation. Encephalopathy is the main complication of surgical portosystemic shunts. It is usually controlled by protein diet restriction, and administration of lactulose or oral antibiotics. In severe forms the patients may be treated by an oesophageal transection with oesophagogastric devascularization, and by a postoperative suppression of the portosystemic shunt using external maneuvers. Posthepatitic liver cirrhosis is frequently complicated by the onset of an hepatocellular carcinoma. Early detection (aFP, DCP, Echography) and curative resection are the best ways to improve long term prognosis. Segmentectomy achieves a good balance between liver function preservation and radical exeresis for tumours less than 5 cm in diameter. Liver transplantation may be considered for the treatment of long-staging cirrhotic patients in whom hepatocarcinoma development has been recognized at an early presymptomatic stage. Hepatic arterial chemoembolization (gelfoam, lipiodol, mitomycin C or doxorubicin) may improve the survival of patients with unresectable malignant disease of the liver. A marked reduction in liver size may occur in the weeks following an effective chemoembolization with objective (CT scan) and subjective improvement (amelioration of specific symptoms). Liver chemoembolization is absolutely contraindicated in the presence of jaundice disordered liver function (Child C) or complete portal venous obstruction. In the last years, the number of patients treated by liver transplantation has greatly increased. Surgical technique, postoperative management, and immunosuppressive therapy account for the dramatic improvement of the results. However, indications for selection of patients and the timing for liver transplantation are still not well defined.
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PMID:[Surgical approach to posthepatitic cirrhotic patient today]. 927 83

The therapy of portal hypertension depends to a significant extent on its clinical manifestation. In cases of acute haemorrhage from oesophageal varices in patients with portal hypertension, the objective of the therapy is to stop the haemorrhage (endoscopically, or by compression by means of a balloon probe) and to decrease the pressure and the reflux within the portal vascular bed. Urgent sclerotisation under the simultanous pharmacologic decrease of portal hypertension is successful in 93-95%. There is an alternative procedure residing in introducing a balloon probe for several hours and subsequent repeated sclerotisation until a complete eradication of varices is achieved regarding the prevention of haemorrhage exacerbation. Urgent surgical solution is on the basis of the results of various investigated studies reserved for patients in whom endoscopic sclerotisation was not successful. Indication of surgical therapy must be also deliberated in candidates for liver transplantation, regarding the possible consequent technical problems after some types of interventions. Endoscopic sclerotisation of oesophageal varices is also an appropriate preparation for transplantation of the liver in patients with liver cirrhosis included into the transplantation programme. TIPS is a perspective new method in the therapy of portal hypertension of both, non-bleeding varices, as well as in other indications. It is also a certain intermediating link in therapy in some patients with liver cirrhosis on the waiting list of candidates for liver transplantation. Pharmacotherapy is a significant part of the portal hypertension therapy. It is appropriate to combine the endoscopic treatment with pharmacotherapy of portal hypertension in both, cases of acute haemorrhage, as well as in the prevention of haemorrhage exacerbation. In cases of acute haemorrhage, the combination of glypressin with nitroglycerin is justified, as well as the therapy by somatostatin. The prevention of haemorrhage exacerbations uses a whole series of vasoactive substances, especially nitrates, beta-blockers and ACE inhibitors. The prevention of the first bleeding includes the prophylactic therapy (endoscopic, pharmacologic, or surgical) recommended only in a selected group of patients under high risk of bleeding. The possible perspective option will reside especially in the combined pharmacological therapy, the fact of which will have to be proven in the future. (Fig. 1, Ref. 25.)
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PMID:[Treatment of portal hypertension]. 958 83

Recent studies have shown that serum activity of angiotensin-converting enzyme (ACE; EC 3.4.15.1) significantly decreases in patients with carcinoma of different localizations. There is no information in literature about measuring this enzyme in primary liver carcinoma patients. The serum activity of ACE has been examined on 15 primary liver carcinoma patients, 10 patients with cirrhosis, and 26 healthy subjects. Serum activity has been determined by spectrophotometric method using synthetic substrate Hip-His-Leu. The results were given in units which correspond to one nmol of hippuric acid released by enzymatic hydrolyze of Hip-His-Leu substrate in one minute on serum milliliter. The results have shown that serum activity of ACE increased in patients with cirrhosis (37.06 +/- 2.9; X +/- SEM; p < 0.05), and decreased in primary liver carcinoma patients (23.44 +/- 1.87; p < 0.01), what was statistically significant in comparison with the activity of the same enzyme in healthy subjects (29.90 +/- 2.72). These results point out the possibility of clinical application of measuring serum ACE activity as one of primary liver carcinoma marker in differential diagnosis of the disease.
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PMID:[Serum angiotensin converting enzyme in patients with primary liver carcinoma]. 1038 37

Spironolactone, a competitive aldosterone receptor antagonist (ARA), has traditionally been the treatment of first choice in idiopathic hyperaldosteronism (IHA) and for preoperative management of aldosterone producing adenoma (APA). Spironolactone is partially absorbed, is extensively metabolized mainly by the liver and its therapeutic properties are attributable to active metabolite canrenone. At therapeutic doses of 25 to 400 mg per day, spironolactone effectively controls blood pressure and hypokalemia in the majority of cases. Endocrine side effect are often associated and mainly consist of gynecomastia, decreased libido and impotence in man and menstrual irregularities in women. Canrenone and the K+ salt of canrenoate are also in clinical use: they avoid the formation of intermediate products with anti-androgenic and progestational actions, resulting in a decreased incidence of side effects. Furthermore, a relatively new selective ARA compound (eplerenone) with reduced affinity for androgen and progesterone receptors, is currently undergoing clinical trials. In essential hypertension aldosterone can contribute to hypertension and increases the incidence of myocardial hypertrophy and cardiovascular events. On the other hand, inhibition of Renin-Angiotensin-Aldosterone System (RAAS) is associated with a decrease in blood pressure, with a regression of left ventricular hypertrophy and a reduction of target organ damage. Thus, ARA have been proposed as complementary treatment associated to ACE inhibitors and angiotensin receptor antagonists. Aldosterone is also known to play an important role in pathophysiolgy of congestive heart failure (CHF). In vitro and in vivo evidences suggest that aldosterone promotes myocardial fibrosis. This effect reflects direct, extra-epithelial actions of aldosterone via cardiac MR which are counteracted by ARAs in animal models. The RAAS is chronically activated in CHF. Non potassium-sparing diuretics further stimulate the RAAS and cause hypokalemia. Thus, use of ARAs in CHF was first proposed to correct potassium and magnesium depletion. At present ARAs are indicated in the management of primary hyperaldosteronism, in oedematous conditions in patients with CHF, in cirrhosis of the liver accompanied by oedema and ascites, in essential hypertension and in hypokalemic states. Its indication as adjunctive therapy of heart failure is currently under investigation. In fact, it is well known that even high doses of ACE inhibitors may not completely suppress the RAAS; aldosterone 'escape' may occur through non angiotensin II dependent mechanisms. Addition of spironolactone to an ACE inhibitor causes marked diuresis and symptomatic improvement. During the last few years, the RALES study (Randomized Aldactone Evaluation Study) was organized to explore the efficacy of combination therapy with spironolactone and ACE inhibitor in patients with CHF, class III or IV NYHA. The study was stopped 18 months early because the results were so statistically and clinically significant that it would be unethical to continue the trial. It is reported a 30 percent decrease in mortality and hospitalisation for cardiac causes in spironolactone-treated group vs placebo group.
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PMID:Aldosterone antagonists in hypertension and heart failure. 1079 May 93

The clinical course of patients with cystic fibrosis (CF) with functionally similar mutations in the CF transmembrane conductance regulator gene is variable and must therefore relate to secondary genetic and environmental factors. We examined the hypothesis that polymorphisms of certain inflammatory mediator and regulatory genes affect clinical outcome by influencing the degree of end-organ damage. By studying the possible association between clinical outcome and angiotensin I-converting enzyme (ACE) and cytokine genotypes by amplification refractory mutation system-polymerase chain reaction, using stored DNA from 261 white patients with CF, we found that ultrasound features of cirrhosis occurred more frequently in patients with the high-producer (DD) rather than the low-producer (II) ACE genotype (odds ratio [95% confidence interval], 3.7 [1.2 to 12]). Moreover, significant pulmonary dysfunction (age at which FEV1 < 50%) was associated with the high-producer ACE genotype (2.3 [1.2 to 4.5]) and transforming growth factor-beta1 genotype (2.6 [1.0 to 6.8]) as well as with age at first colonization with Pseudomonas aeruginosa (9.1 [1.1 to 72]). We conclude that the high-producer ACE genotype predicts patients with CF who have an increased chance of developing portal hypertension; and high-producer ACE and TGF-beta1 genotypes are secondary genetic factors contributing to pulmonary dysfunction in these patients.
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PMID:End-organ dysfunction in cystic fibrosis: association with angiotensin I converting enzyme and cytokine gene polymorphisms. 1255 16

In surgical pathology, focal nodular hyperplasia (FNH) is sometimes difficult to diagnose, and liver cirrhosis (LC) and hepatocellular adenoma (HA) are often among the differential diagnoses. Recently, we found a reduced expression of angiotensin I-converting enzyme (CD143) in FNH compared with cirrhotic and noncirrhotic liver. Intrigued by this observation, we investigated the expression pattern of CD143 in FNH, LC, and HA and its possible diagnostic value. The expression of CD143 was studied by immunohistochemistry in 20 FNHs, 13 corresponding extralesional noncirrhotic liver parenchyma, 20 patients with LC, and four HAs. Endothelial cells were identified with antibodies directed against CD31 and CD34. CD31+, CD34+, and CD143+ sinusoidal endothelial cells were found in extralesional liver, LC, HA, and FNH. However, the number of CD143+ sinusoidal endothelial cells and the intensity of immunostaining were significantly reduced in FNH compared with extralesional liver, LC, and HA. The expression of CD143 was further assessed using a numerical scoring system ranging from 0 to 6. The mean immunoreactivity score for CD143 was 2.4 +/- 1.7 for sinusoidal endothelial cells in FNH, 5.7 +/- 0.6 in extralesional liver, 4.8 +/- 1.1 in LC, and 5.8 +/- 0.5 in HA. The differences between the mean immunoreactivity scores for CD143 were highly significant. The difference between FNH and extralesional liver was confirmed on transcriptional level by fluorescence-mediated real-time RT-PCR, which also showed a significantly decreased level of CD143 mRNA in FNH. Our study provides evidence that CD143 is down-regulated in FNHs and that the phenotype of endothelial cells lining the sinusoids in FNH differs from those in non-neoplastic liver, LC, and HA. The observed variations in expression patterns for CD143 might be of diagnostic use in surgical pathology.
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PMID:Angiotensin I-converting enzyme (CD143) is down-regulated in focal nodular hyperplasia of the liver. 1470 68


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