Rudolf W. Ammann
University of Zurich
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Featured researches published by Rudolf W. Ammann.
The New England Journal of Medicine | 1993
Albert B. Lowenfels; Patrick Maisonneuve; G. Cavallini; Rudolf W. Ammann; Paul Georg Lankisch; Jens Rikardt Andersen; Eugene P. DiMagno; Åke Andrén-Sandberg; Lennart Domellof
Background The results of case-control studies and anecdotal reports suggest that pancreatitis may be a risk factor for pancreatic cancer, but there have been no studies of sufficient size and power to assess the magnitude of the relation between these two diseases. Methods and Results We undertook a multicenter historical cohort study of 2015 subjects with chronic pancreatitis who were recruited from clinical centers in six countries. A total of 56 cancers were identified among these patients during a mean (±SD) follow-up of 7.4 ±6.2 years. The expected number of cases of cancer calculated from country-specific incidence data and adjusted for age and sex was 2.13, yielding a standardized incidence ratio (the ratio of observed to expected cases) of 26.3 (95 percent confidence interval, 19.9 to 34.2). For subjects with a minimum of two or five years of follow-up, the respective standardized incidence ratios were 16.5 (95 percent confidence interval, 11.1 to 23.7) and 14.4 (95 percent confidence interval, 8...
Gastroenterology | 1999
Rudolf W. Ammann; Beat Muellhaupt
BACKGROUND & AIMS The pain pattern of chronic pancreatitis (CP) and its surgical implications are discussed. The aim of this study was to (1) define typical pain patterns, (2) correlate pain patterns with the presumptive causes of the pain, and (3) compare the natural history of patients treated conservatively or surgically with respect to pain relief, pancreatic dysfunction, and clinical outcome. METHODS A cohort in this prospective long-term study included 207 patients with alcoholic CP (91 without and 116 with surgery for pain relief). A clinically based staging system was applied to characterize pain in the evolution from onset to end-stage CP. RESULTS Average duration of CP was 17 years. In early-stage CP, episodes of recurrent (acute) pancreatitis predominated. Chronic pain was typically associated with local complications (mainly pseudocysts, 84 of 155; 54%), relieved definitely by a single (drainage) procedure in approximately two thirds of patients. Additional surgery was required for late pain recurrence in 39 patients (34%), primarily symptomatic cholestasis (18 of 39; 46%). All patients achieved complete pain relief in advanced CP. CONCLUSIONS In our experience, relief of chronic pain regularly follows selective surgery tailored to the presumptive pain cause or occurs spontaneously in uncomplicated advanced CP.
Emerging Infectious Diseases | 2003
Petra Kern; Karine Bardonnet; Elisabeth Renner; Herbert Auer; Zbigniew Pawlowski; Rudolf W. Ammann; Dominique A. Vuitton; Peter Kern
Surveillance for alveolar echinococcosis in central Europe was initiated in 1998. On a voluntary basis, 559 patients were reported to the registry. Most cases originated from rural communities in regions from eastern France to western Austria; single cases were reported far away from the disease-“endemic” zone throughout central Europe. Of 210 patients, 61.4% were involved in vocational or part-time farming, gardening, forestry, or hunting. Patients were diagnosed at a mean age of 52.5 years; 78% had symptoms. Alveolar echinococcosis primarily manifested as a liver disease. Of the 559 patients, 190 (34%) were already affected by spread of the parasitic larval tissue. Of 408 (73%) patients alive in 2000, 4.9% were cured. The increasing prevalence of Echinococcus multilocularis in foxes in rural and urban areas of central Europe and the occurrence of cases outside the alveolar echinococcosis–endemic regions suggest that this disease deserves increased attention.
Gut | 2005
Patrick Maisonneuve; Albert B. Lowenfels; B. Müllhaupt; G. Cavallini; Paul Georg Lankisch; Jens Rikardt Andersen; Eugene P. DiMagno; Åke Andrén-Sandberg; Lennart Domellof; L Frulloni; Rudolf W. Ammann
Background: Smoking is a recognised risk factor for pancreatic cancer and has been associated with chronic pancreatitis and also with type II diabetes. Aims: The aim of this study was to investigate the effect of tobacco on the age of diagnosis of pancreatitis and progression of disease, as measured by the appearance of calcification and diabetes. Patients: We used data from a retrospective cohort of 934 patients with chronic alcoholic pancreatitis where information on smoking was available, who were diagnosed and followed in clinical centres in five countries. Methods: We compared age at diagnosis of pancreatitis in smokers versus non-smokers, and used the Cox proportional hazards model to evaluate the effects of tobacco on the development of calcification and diabetes, after adjustment for age, sex, centre, and alcohol consumption. Results: The diagnosis of pancreatitis was made, on average, 4.7 years earlier in smokers than in non-smokers (p = 0.001). Tobacco smoking increased significantly the risk of pancreatic calcifications (hazard ratio (HR) 4.9 (95% confidence interval (CI) 2.3–10.5) for smokers v non-smokers) and to a lesser extent the risk of diabetes (HR 2.3 (95% CI 1.2–4.2)) during the course of pancreatitis. Conclusions: In this study, tobacco smoking was associated with earlier diagnosis of chronic alcoholic pancreatitis and with the appearance of calcifications and diabetes, independent of alcohol consumption.
Pancreas | 1997
Rudolf W. Ammann
Symposium participants: Guido Adler* Ulm, Germany; Rudolf W. Ammann** Zurich, Switzerland; Simmy Bank, New York, NY, U.S.A.; Peter Banks, Boston, MA, U.S.A.; Hans Beger, Ulm, Germany; Christoph Beglinger** Basel, Switzerland; Daniel Bimmler, Zurich, Switzerland; Dale E. Bockman, Atlanta, GA, U.S.A.;
Nature Genetics | 2006
Heiko Witt; Miklós Sahin-Tóth; Olfert Landt; Jian-Min Chen; Thilo Kähne; Joost P. H. Drenth; Zoltán Kukor; Edit Szepessy; Walter Halangk; Stefan Dahm; Klaus Rohde; Hans Ulrich Schulz; Cédric Le Maréchal; Nejat Akar; Rudolf W. Ammann; Kaspar Truninger; Mario Bargetzi; Eesh Bhatia; Carlo Castellani; Giulia Martina Cavestro; Milos Cerny; Giovanni Destro-Bisol; Gabriella Spedini; Jan B.M.J. Jansen; Monika Koudova; Eva Rausova; Milan Macek; Núria Malats; Francisco X. Real; Hans Jürgen Menzel
Chronic pancreatitis is a common inflammatory disease of the pancreas. Mutations in the genes encoding cationic trypsinogen (PRSS1) and the pancreatic secretory trypsin inhibitor (SPINK1) are associated with chronic pancreatitis. Because increased proteolytic activity owing to mutated PRSS1 enhances the risk for chronic pancreatitis, mutations in the gene encoding anionic trypsinogen (PRSS2) may also predispose to disease. Here we analyzed PRSS2 in individuals with chronic pancreatitis and controls and found, to our surprise, that a variant of codon 191 (G191R) is overrepresented in control subjects: G191R was present in 220/6,459 (3.4%) controls but in only 32/2,466 (1.3%) affected individuals (odds ratio 0.37; P = 1.1 × 10−8). Upon activation by enterokinase or trypsin, purified recombinant G191R protein showed a complete loss of trypsin activity owing to the introduction of a new tryptic cleavage site that renders the enzyme hypersensitive to autocatalytic proteolysis. In conclusion, the G191R variant of PRSS2 mitigates intrapancreatic trypsin activity and thereby protects against chronic pancreatitis.
Emerging Infectious Diseases | 2007
Alexander Schweiger; Rudolf W. Ammann; Daniel Candinas; Pierre-Alain Clavien; Johannes Eckert; Bruno Gottstein; Nerman Halkic; Beat Muellhaupt; Bettina Mareike Prinz; Juerg Reichen; Philip E. Tarr; Paul R. Torgerson; Peter Deplazes
An increase in fox population has led to an increase in incidence of human alveolar echinococcosis.
Journal of Hepatology | 2008
Paul R. Torgerson; Alexander Schweiger; Peter Deplazes; Maja Pohar; Jürg Reichen; Rudolf W. Ammann; Philip E. Tarr; Nerman Halkik; Beat Müllhaupt
BACKGROUND/AIMS Alveolar echinococcosis (AE) is a serious liver disease. The aim of this study was to explore the long-term prognosis of AE patients, the burden of this disease in Switzerland and the cost-effectiveness of treatment. METHODS Relative survival analysis was undertaken using a national database with 329 patient records. 155 representative cases had sufficient details regarding treatment costs and patient outcome to estimate the financial implications and treatment costs of AE. RESULTS For an average 54-year-old patient diagnosed with AE in 1970 the life expectancy was estimated to be reduced by 18.2 and 21.3 years for men and women, respectively. By 2005 this was reduced to approximately 3.5 and 2.6 years, respectively. Patients undergoing radical surgery had a better outcome, whereas the older patients had a poorer prognosis than the younger patients. Costs amount to approximately Euro108,762 per patient. Assuming the improved life expectancy of AE patients is due to modern treatment the cost per disability-adjusted life years (DALY) saved is approximately Euro6,032. CONCLUSIONS Current treatments have substantially improved the prognosis of AE patients compared to the 1970s. The cost per DALY saved is low compared to the average national annual income. Hence, AE treatment is highly cost-effective in Switzerland.
Gastroenterology | 1988
Rudolf W. Ammann; R. Muench; R. Otto; H. Buehler; A.U. Freiburghaus; W. Siegenthaler
Pancreatic calcifications are virtually pathognomonic of chronic pancreatitis and develop in up to 90% of patients with alcoholic chronic pancreatitis in series with long-term results. We investigated the natural course of pancreatic calcification in a prospective longitudinal study over the past 23 yr. All patients were studied at regular intervals with particular regard to etiology, clinical findings, surgery, pancreatic function, and pancreatic calcification visible by x-ray (e.g., film series in three projections centered on the pancreas). We evaluated the findings of 107 patients with x-ray documentation of pancreatic calcification in at least three film series over a period of 4 yr or longer. Eighty-four patients had alcoholic chronic pancreatitis (group A) and 23 patients had nonalcoholic chronic pancreatitis (group B). Four hundred seventy-two film series of group A and one hundred forty-two film series of group B were reviewed independently by two expert teams. Both series were graded according to a score system in terms of intensity and distribution of pancreatic calcification (correlation of grading r = 0.91). The duration of calcification averaged 10 yr in group A and 12.6 yr in group B. Similar dynamic changes of pancreatic calcification were noted in groups A and B. Chronologically, three phases of evolution could be distinguished. After an initial increase (phase 1), greater than 50% of cases reached a plateau of stationary calcification (phase 2). Approximately one-third of cases showed a marked decrease of calcification in late phases of chronic pancreatitis (phase 3). Dissolution of pancreatic stones was related primarily to duration of chronic pancreatitis (duration of calcification and marked pancreatic dysfunction), and occurred frequently (but not exclusively) in patients after ductal drainage procedures. These results indicate that spontaneous dissolution of pancreatic stones is a rather common biologic phenomenon. The factors responsible for dissolution of stones remain to be elucidated.
Pancreas | 1994
Rudolf W. Ammann; Bea Muellhaupt; Christa Meyenberger; Philipp U. Heitz
140 patients with alcoholic acute (recurrent) pancreatitis were enrolled in a prospective long-term study over the last 16 years. Regular control studies regarding progression to advanced chronic pancreatitis were performed. Based on long-term outcome the patients were classified into two groups: group A (n = 109; 77.8%) with progression to advanced chronic pancreatitis (84% with calcification, 95% with exocrine insufficiency) and group B (n = 31; 22.2%) without progression (no calcification, no exocrine insufficiency). The two groups were comparable in age, sex, and mean duration of disease from onset (13.1 2 5.2 vs. 13.8 ± 4.9 years). Surgery for pseudocysts was performed in 47% of group A and in 29% of group B. In group B, no pancreatic duct dilatation occurred (in 86% >8 years from onset). However, 4 of 7 patients with adequate histology showed unequivocal chronic pancreatitis. Surprisingly, all patients of group B except two got spontaneous lasting pain relief irrespective of alcohol intake or normal pancreatic function. Our findings indicate that a subgroup of alcoholic acute pancreatitis does not progress to advanced chronic pancreatitis. This subgroup may be identical with “small duct” chronic pancreatitis. The factors responsible for progression (group A) or nonprogression (group B) remain to be elucidated.