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Dive into the research topics where Claus Niederau is active.

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Featured researches published by Claus Niederau.


The New England Journal of Medicine | 1985

Survival and Causes of Death in Cirrhotic and in Noncirrhotic Patients with Primary Hemochromatosis

Claus Niederau; Rudolf Fischer; Amnon Sonnenberg; Wolfgang Stremmel; Hans J. Trampisch; Georg Strohmeyer

We analyzed survival and causes of death among 163 patients with primary hemochromatosis diagnosed between 1959 and 1983. The mean follow-up period was 10.5 +/- 5.6 years (+/- S.D.). Cumulative survival was 92 per cent at 5 years, 76 per cent at 10 years, 59 per cent at 15 years, and 49 per cent at 20 years. Life expectancy was reduced in patients with cirrhosis of the liver as compared with those without cirrhosis (P less than or equal to 0.05), in patients with diabetes mellitus as compared with those without diabetes (P less than or equal to 0.002), and in patients who could not be depleted of iron during the first 18 months of venesection therapy as compared with those who could be depleted (P less than or equal to 0.001). Prognosis was not influenced by sex (P less than or equal to 0.5). Patients without cirrhosis had a life expectancy that was not different from that expected in an age- and sex-matched normal population. Analysis of the causes of death in 53 patients, as compared with the normal population, showed that liver cancer was 219 times more frequent among the patients (16 patients), cardiomyopathy was 306 times more frequent (3 patients), liver cirrhosis was 13 times more frequent (10 patients), and diabetes mellitus was 7 times more frequent (3 patients). Death rates for other causes, including extrahepatic carcinomas (seven patients), were not different from the rates expected. We conclude that patients with hemochromatosis diagnosed in the precirrhotic stage and treated by venesection have a normal life expectancy, whereas cirrhotic patients have a shortened life expectancy and a high risk of liver cancer even when complete iron depletion has been achieved.


The New England Journal of Medicine | 1996

Long-Term Follow-up of HBeAg-Positive Patients Treated with Interferon Alfa for Chronic Hepatitis B

Claus Niederau; Tobias Heintges; Stefan Lange; Georg Goldmann; Christoph M. Niederau; Leonhard Mohr; Dieter Häussinger

BACKGROUND In patients with chronic hepatitis B, treatment with interferon alfa and the consequent loss of hepatitis B e antigen (HBeAg) from the blood leads to a reduction in inflammatory activity, but the clinical benefits of this treatment have not been established. We evaluated whether HBeAg seroconversion induced by interferon alfa improves clinical outcome. METHODS We studied prospectively a cohort of 103 patients treated with interferon alfa for chronic hepatitis B; the mean (+/- SD) follow-up was 50.0 +/- 19.8 months. Fifty-three untreated patients served as controls. RESULTS After treatment with interferon alfa, 53 of 103 patients no longer had detectable HBeAg or hepatitis B virus DNA, although only 10 patients became seronegative for hepatitis B surface antigen (HBsAg) (Kaplan-Meier estimates of cumulative clearance rates at five years, 56.0 percent for HBeAg and 11.6 percent for HBsAg). Of the 53 untreated patients, only 7 spontaneously eliminated HBeAg (28.1 percent at five years), and all remained positive for HBsAg (p < 0.001 for the Comparison with the treated patients, by the proportional-hazards model). During follow-up, 6 of the 103 treated patients died of liver failure, and 2 needed liver transplantation, all 8 were persistently positive for HBeAg. In another eight treated patients, complications of cirrhosis developed; all but one of these patients remained positive for HBeAg. Overall survival and survival without clinical complications were significantly longer in patients who were seronegative for HBeAg after therapy with interferon alfa than in those who remained seropositive (P = 0.004 and P = 0.018, respectively). In a regression analysis, clearance of HBeAg was the strongest predictor of survival. Of the 53 untreated patients, 13 had severe complications (including 4 deaths and 1 need for liver transplantation); all 13 continued to be HBeAg-positive. CONCLUSIONS In patients with chronic hepatitis B infection, the clearance of HBeAg after treatment with interferon alfa is associated with improved clinical outcomes.


Gastroenterology | 1985

Caerulein-induced acute necrotizing pancreatitis in mice: protective effects of proglumide, benzotript, and secretin.

Claus Niederau; Linda D. Ferrell; James H. Grendell

The onset, course, and regression of the biochemical and structural alterations associated with pancreatitis induced by various doses of caerulein were studied in the mouse. In addition, the protective effect of secretin was compared with that of the cholecystokinin-receptor antagonists proglumide and benzotript. Subcutaneous or intraperitoneal injections of caerulein induced increases in serum amylase concentration and pancreatic weight and histologic evidence of acute pancreatitis, all effects being dose-related. Cytoplasmic vacuoles were the earliest histologic alterations. As the pancreatitis progressed these vacuoles increased to an enormous size. Interstitial inflammation and acinar cell necrosis were prominent after 6 h, reached a maximum after 12 h, and mostly disappeared after 4 days. During the course of pancreatitis approximately 40% of the acinar cells showed signs of severe degeneration or necrosis at the most effective doses of caerulein. Electron microscopy showed both intact and degenerating granules inside the vacuoles. Signs of basolateral exocytosis of zymogen granules were not observed. During the regression of pancreatitis, focal atrophy was a remarkable histologic finding. Repetitive initiation of pancreatitis (six courses of caerulein injections over 5 wk) produced marked focal atrophy and early fibrosis. High doses of proglumide or benzotript markedly ameliorated both the biochemical and structural alterations induced by caerulein. Secretin, even at very high doses, had only minor protective effects. This study presents a model of acute necrotizing pancreatitis in which the severity of the induced pancreatitis ranges dose-dependently from mild interstitial inflammation to severe necrosis. The ultrastructural alterations described herein support the hypothesis that the trigger mechanism of acute pancreatitis appears to be a primary intracellular event rather than an interstitial event that secondarily damages the acinar cells.


Annals of Internal Medicine | 1991

Wilson Disease: Clinical Presentation, Treatment, and Survival

Wolfgang Stremmel; Karl-Wilhelm Meyerrose; Claus Niederau; Harald Hefter; Georg Kreuzpaintner; Georg Strohmeyer

OBJECTIVE To evaluate the diagnostic features, clinical course, and overall long-term survival of patients with Wilson disease. DESIGN Retrospective cohort study with a mean follow-up period of 14.2 years. SETTING A university medical center and a community hospital. PATIENTS Fifty-one consecutive patients with Wilson disease were evaluated between 1957 and 1989. INTERVENTIONS Patients were treated with D-penicillamine (600 to 1800 mg/d). Two patients with end-stage liver disease had liver transplantation. MAIN RESULTS Initial symptoms occurred at a mean age of 15.5 years. At diagnosis, the most common neurologic signs were dysarthria, tremor, writing difficulties, and ataxia followed by hypersalivation and headache. Somatic symptoms included abdominal pain, hepatomegaly, splenomegaly, cirrhosis of the liver, and thrombocytopenia. The mean serum concentrations of ceruloplasmin and copper were 44 mg/L and 4.7 mumol/L, respectively. The mean basal urinary copper excretion was 5.5 mumol/d, and the mean hepatic copper concentration was 19.6 mumol/g dry weight. Free serum copper concentration (mean, 2.7 mumol/L) was a reliable indicator of disease and was useful in assessing the effectiveness of therapy (values less than 1.6 mumol/L). Treatment with D-penicillamine improved most of the hematologic and neurologic abnormalities but had little effect on hepatomegaly and splenomegaly and did not reverse cirrhosis. Two patients died of fulminant hepatic failure during the observation period, whereas two others with end-stage liver disease had successful liver transplantation and remain asymptomatic. Long-term survival of patients with Wilson disease was similar to that of age- and sex-matched controls. CONCLUSION Our results suggest that long-term treatment of patients with Wilson disease with D-penicillamine can relieve symptoms and improve prognosis.


Pancreas | 1992

Diagnosis of pancreatic carcinoma : imaging techniques and tumor markers

Claus Niederau; James H. Grendell

In view of the increasing number of new imaging techniques and serum tumor markers, it is not well established which combination or which order of tests may provide the most information for diagnosis of pancreatic carcinoma. This review determines the diagnostic value of the various tests and evaluates which combination of tests may provide the most information and what may be considered to be a current rational approach to the diagnosis of pancreatic carcinoma. In the present analysis endoscopic retrograde chol-angiopancreatography (ERCP) provided a 92% sensitivity that exceeded the 83% and 74% sensitivities calculated for computed tomography (CT) and ultrasound, respectively. The specificity of all three imaging techniques exceeded 90%. Serum determination of CA 19–9 yielded an 83% sensitivity, which was considerably higher than sensitivities of carcinoembryonic antigen and various other tumor markers. The combination of CA 19–9 and ultrasound improved the sensitivity of each test performed alone by 10–15%. Fine-needle biopsy allows diagnosis of pancreatic carcinoma with a sensitivity of 83% and an almost perfect specificity of 99%. On the basis of these data, the combination of ultrasound and determination of CA 19–9 is recommended as the initial tests when pancreatic carcinoma is suspected. CT also must be performed if ultrasound is indeterminant or inconsistent with the clinical evaluation, as well as in patients with negative ultrasound but abnormal CA 19–9. Negative results of CT, ultrasound, and CA 19–9 will exclude pancreatic carcinoma in most patients. A positive ultrasound or CT result usually leads to fine-needle biopsy, which helps avoid most diagnostic laparotomies. ERCP must be performed in patients where ultrasound, CT, and fine-needle biopsy do not clarify the diagnosis. In the majority of patients with pancreatic carcinoma, noninvasive imaging techniques such as ultrasound and CT also allow adequate staging. In some patients, however, laparoscopy and angiography may need to be performed for strategic planning of further therapy. Although modern imaging techniques and serum tumor markers allow diagnosis of pancreatic carcinomas as small as 2–3 cm and help avoid most diagnostic laparotomies, this improvement in diagnostic capability has as yet not significantly improved the prognosis.


Gastroenterology | 1982

Detection of Crohn's Disease by Ultrasound

Amnon Sonnenberg; Joachim F. Erckenbrecht; Peter Peter; Claus Niederau

The target appearance of grey scale ultrasound is thought to be a characteristic sign of gastrointestinal wall thickening. It consists of a strong echogenic center surrounded by a sonolucent rim. In a prospective controlled study, the sensitivity and specificity of the ultrasonic B-scan for Crohns disease were investigated. Fifty-one patients with Crohns disease and 124 control subjects were studied. Sensitivity and specificity of the ultrasonic target appearance for Crohns disease were 76% and 88%, respectively. When additional ultrasonic signs of inflammatory bowel disease were considered, sensitivity and specificity rose to 84% and 91%, respectively. Both colon and ileum were affected in 85% of the true-positive and in 8% of the false-negative targets. The Crohns disease activity index was 213 +/- 136 in patients with true-positive targets and 167 +/- 118 in patients with false-negative target appearances. Most false-positive target phenomena arose from gastrointestinal tumors. It is concluded that ultrasound is a suitable complementary method for the detection of Crohns disease.


Digestion | 1992

Treatment of Pain with Pancreatic Extracts in Chronic Pancreatitis: Results of a Prospective Placebo-Controlled Multicenter Trial

Joachim Mössner; Roger Secknus; Jürgen Meyer; Claus Niederau; Guido Adler

According to the theory of negative feedback regulation of pancreatic enzyme secretion by proteases, treatment with pancreatic extracts has been proposed to lower pain in chronic pancreatitis by decreasing pancreatic duct pressure. We conducted a prospective placebo-controlled double blind multicenter study to investigate the effect of porcine pancreatic extracts on pain in chronic pancreatitis. 47 patients with pain (41 males, 6 females) due to chronic pancreatitis documented by sonography, endoscopic retrograde cholangiopancreatography, and CT were included. Exclusion criteria were steatorrhea above 30 g/day, gastric or pancreatic resections in the history, and serum bilirubin above 1.5 mg/dl. Patients received pancreatic extracts (acid-protected microtablets; Panzytrat -20,000; 5 x 2 capsules/day; proteases/capsule 1,000 Pharmacopoea europaea units) for 14 days followed by treatment with placebo for another 14 days or vice versa. Pain (graded from 0 to 3) and concomitant use of analgesics (N-butylscopolaminiumbromide and tramadol) were recorded by diary. Physical examination and blood chemistry were done at day -1, 15 and 29. Quantitative stool fat was determined at days -2/-1, 13/14 and 27/28. 43 patients completed the studies. Pain improved in most patients irrespective of whether they started with placebo or verum. There was no significant difference between both treatment arms. We conclude that pancreatic extracts are not very efficient in lowering pain.


Journal of Hepatology | 2003

HFE mutations and chronic hepatitis C: H63D and C282Y heterozygosity are independent risk factors for liver fibrosis and cirrhosis

A. Erhardt; Andrea Maschner-Olberg; Claudia Mellenthin; Günther Kappert; Ortwin Adams; Andreas Donner; Reinhard Willers; Claus Niederau; Dieter Häussinger

BACKGROUND/AIMS The impact of heterozygous HFE mutations on the course of chronic hepatitis C and iron indices was studied. METHODS Ferritin, transferrin saturation (TS), serum iron, C282Y and H63D mutations were determined in 401 patients with chronic hepatitis C virus (HCV) infection and 295 healthy controls. Liver histologies were available in 217 and HCV genotypes in 339 patients. RESULTS Allele frequencies of the C282Y and H63D mutation did not differ between HCV patients and healthy controls (6.95 vs. 6.2%; 14.75 vs. 16.4%; n.s.). HFE heterozygous HCV patients had higher ferritin (349+/-37 vs. 193+/-15 microg/l; P<0.0005), TS (38+/-2 vs. 32+/-1%; P<0.0005), serum iron (144+/-6 vs. 121+/-3 microg/dl; P<0.0005), semiquantitative liver iron staining (0.26+/-0.07 vs. 0.09+/-0.03; P<0.006) and fibrosis scores (1.9+/-0.2 vs. 1.4+/-0.1; P<0.003) compared to HFE wildtypes. By multivariate regression analysis odds ratios for liver cirrhosis were 5.9 (confidence interval (CI) 1.6-22.6; P<0.009) for C282Y heterozygotes and 2.9 (CI 1.0-8.4; P<0.05) for H63D heterozygotes compared to HFE wildtypes. Considering all HFE heterozygous HCV patients, odds ratios of 3.6 (CI 1.4-9.3; P<0.009) for cirrhosis and 3.1 (CI 1.3-7.3; P<0.009) for fibrosis were calculated. CONCLUSIONS C282Y or H63D heterozygosity is an independent risk factor for liver fibrosis and cirrhosis in HCV infected individuals. Screening for HFE mutations should be considered in HCV infection.


Free Radical Research | 1997

Vitamin E Improves the Aminotransferase Status of Patients Suffering from Viral Hepatitis C: A Randomized, Double-Blind, Placebo-Controlled Study

A Von Herbay; Wilhelm Stahl; Claus Niederau; Helmut Sies

UNLABELLED Vitamin E has been shown to protect against liver damage induced by oxidative stress in animal experiments. Based on our previous findings of diminished vitamin E levels in patients suffering from viral hepatitis, we treated 23 hepatitis C patients refractory to alpha-interferon therapy with high doses of vitamin E (2 x 400 IU RRR-alpha-tocopherol/day) for 12 weeks. STUDY DESIGN pro-spective randomized double-blind crossover design. Clinical parameters including alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined for monitoring the disease state, in parallel vitamin E plasma levels and plasma lipids were determined. The plasma levels of the alpha-tocopherol were increased about 2-fold in all 23 patients. In 11 of 23 patients the clinical parameters indicative of liver damage were improved during the phase of vitamin E treatment (48% responders). ALT levels in responders were lowered by 46% and AST levels were lowered by 35% after 12 weeks of vitamin E treatment. Cessation of vitamin E treatment was followed by a rapid relapse of ALT and AST elevation, whereas retreatment led to a reproducible ALT decrease by 45% and AST decrease of 37% after a 6 months followup. Since vitamin E is non-toxic even at elevated doses ingested over extended periods, we suggest the treatment of patients refractory to alpha-interferon therapy suffering from hepatitis C with vitamin E as a supportive therapy.


Pancreas | 1992

Effects of antioxidants and free radical scavengers in three different models of acute pancreatitis.

Claus Niederau; Marcus Niederau; Franz Borchard; Klaus Ude; Reinhard Lüthen; Georg Strohmeyer; Linda D. Ferrell; James H. Grendell

The present studies were done to evaluate the therapeutic potential of several antioxidants and free radical scavengers in three different models of acute pancreatitis. (a) Edematous pancreatitis with acinar cells necrosis was induced by seven hourly intraperitoneal injections of 50 > of caerulein per kg in mice. (b) Hemorrhagic pancreatitis was induced by feeding a choline-deficient, ethionine-supplemented (CDE) diet in mice. (c) Hemorrhagic pancreatitis was induced by retrograde infusion of 0.6 ml of 5% sodium taurocholate into the pancreatic duct in rats. The following antioxidants and free radical scavengers were given at various doses intravenously, subcutaneously, or in-traperitoneally before the onset of pancreatitis: Ebselen [2-phenyl-1,2-benziso-selenazol-3(2H)-one], superoxide dismutase, catalase, deferoxamine (Des-feral), dimethyl sulfoxide, or allopurinol. The severity of pancreatitis was assessed at various times after its onset by determination of serum amylase and pancreatic weight (edema), by grading of histological alterations, and by determination of survival (survival determined in models of hemorrhagic pancreatitis). In general, free radical scavengers and antioxidants ameliorated edema and inflammation to a greater degree than necrosis and the increase in serum amylase. Superoxide dismutase (as did Ebselen in previous studies) exerted beneficial effects on survival in diet-induced pancreatitis in the absence of marked effects on pancreatic necrosis, suggesting that these beneficial effects are due to amelioration of extrapancreatic complications that often contribute to mortality in acute pancreatitis. None of the antioxidants had major beneficial effects in taurocholate-induced hemorrhagic pancreatitis. Thus, formation of free radicals may be important for progression and outcome in diet-induced and, to a lesser degree, in caerulein-induced pancreatitis but not at all in taurocholate-induced pancreatitis. Different models of pancreatitis may, therefore, involve different degrees and mechanisms of free radical formation. Despite the amelioration of edema and the beneficial effects on mortality seen for some antioxidants in some of the models, antioxidants and free radical scavengers appear to have only a limited potential for treatment of acute pancreatitis.

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Wolfgang Stremmel

University Hospital Heidelberg

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Tobias Heintges

University of Düsseldorf

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