Search PubMed⌕ Search

Biomedical subjects

M Rothmund

Publications and source records attributed to M Rothmund.

At least 91 records · Page 5Linked to original sources
PubMed1999

[Expenditure and reliability of ICD/ICPM-coding in routine surgery].

Because of the changing legal basis for hospital reimbursement German hospitals have to classify their cases by ICD-9- and an adapted ICPM code (OPS-301) and have to give an advance calculation of the Diagnosis Related Groups (DRG) starting from January 1996. From January 1st 1996 to the 31st of December 1996 all diagnoses and therapies in a general surgery hospital were classified according to ICD-9- and ICPM (OPS-301). This coding was not computer-assisted but was controlled in a multiple step process. As a consequence 4.6% incorrect codes were found which were irrelevant for reimbursement. 7.2% misclassifications relevant for funding were detected with an obvious learning curve within the first 6 months. The calculation of the distribution of diagnoses and therapies reveals that 80 to 85% of the total spectrum in a general surgery hospital (including vascular and thoracic surgery) were covered by 200 diagnostic and therapeutic codes, respectively. This investigation confirms the need for a physician-based control system of diagnostic and therapeutic coding to minimise economic risks.

Diagnosis-Related Groups↗
PubMed1998

[Germline mutations in the MEN1 gene: basis for predictive genetic screening and clinical management of multiple endocrine neoplasia type 1 (MEN1) families].

BACKGROUND AND OBJECTIVE: Mutations in the MEN 1 gene were recently discovered as the causative genetic defect of the autosomal dominantly inherited multiple endocrine neoplasia type 1. It was the aim of this study to evaluate the spectrum of MEN 1 mutations in our own series of patients in order to obtain a basis for predictive family screening. PATIENTS AND METHODS: Genomic DNA from peripheral blood of 21 patients with MEN 1, members of 14 non-related MEN 1 families, was examined for MEN 1 germ-line mutations by means of single-strand conformation variant analysis (SSCP) and direct DNA sequencing. In addition, blood from 20 asymptomatic family members of five families was tested for its predictive value. RESULTS: Eleven different heterozygotic germ-line mutations, among them eight frameshift, two missense and one nonsense mutations, were identified. In four of the 20 asymptomatic members from five MEN 1 families who had been tested after appropriate genetic counselling, the MEN 1 mutation characteristic for the particular family was found. Clinical screening programme in three mutation carriers revealed abnormal findings in all three: one primary hyperparathyroidism, one prolactinoma and one nonfunctioning pancreatic tumour each. The 16 family members without MEN 1 mutation were spared further unnecessary screening investigations. CONCLUSION: Although the function of the MEN 1 gene is not yet known, molecular genetic tests provide a basis for genetic counselling, predictive genetic screening and clinical management of MEN 1 families.

Adult↗
PubMed1998

[Postoperative complications and long-term results of the surgical treatment of immunogenic Basedow's disease].

BACKGROUND AND OBJECTIVE: The surgical options for immunogenic Grave's disease (hyperthyroidism with ophthalmopathy) are not uniform. This study was undertaken to compare the effectiveness of several types of operation. PATIENTS AND METHODS: In a retrospective study the data on 99 patients with Grave's disease (aged 10 to 71 years, mean 35 years), operated on from 1987 to 1996 by 28 different surgeons, were analysed. Follow-up examinations were then undertaken a mean of 42 months (range of 12-108 months) postoperatively. RESULTS: Bilateral subtotal thyroid resection had been performed in 45 patients, unilateral subtotal resection with contralateral hemithyroidectomy in 49 and total thyroidectomy in five. Re-operation for postoperative bleeding was necessary in three patients. At follow-up two patients were found to have recurrent nerve palsy. Four patients had to be treated for mild chronic hyperparathyroidism. There was no significant difference between the different operation regarding type and frequency of complications. At following-up examination none of the patients had hyperthyroidism. 37 of 50 patients with endocrine ophthalmopathy were improved after the operation. CONCLUSIONS: With a standardized operative technique and retention of less than 6 g of thyroid tissue a recurrence of hyperthyroidism can be reliably prevented. This form of treatment can be achieved with an acceptable complication rate, which is unrelated to the type of operation.

Adolescent↗
PubMed1998

Localization, malignant potential, and surgical management of gastrinomas.

Between 1987 and 1996 a total of 25 patients with proved Zollinger-Ellison syndrome (ZES) have been treated in our department. If preoperative imaging studies did not show diffuse metastatic disease, patients were scheduled for operation with a standardized surgical approach including thorough exploration and intraoperative ultrasonography (IOUS) of the pancreas and a longitudinal duodenotomy, with separate palpation of the anterior and posterior walls. Postoperatively, patients were followed up by physical examination, fasting gastrin levels, and the secretin stimulation test. Altogether 10 patients had duodenal wall gastrinoma, 14 patients pancreatic gastrinoma, and the tumor was not found in 1 patient. Only 15 tumors (60%) (2 duodenal wall and 13 pancreatic gastrinomas) could be visualized preoperatively. Intraoperatively, 24 of 25 primary gastrinomas were localized. The mean size of duodenal wall gastrinomas (9.6 mm) was significantly smaller than that of pancreatic gastrinomas (28.7 mm) (p < 0.05). At the time of surgical exploration, five duodenal and seven pancreatic gastrinomas had metastasized. The incidence of lymph node metastases was similar for both tumor sites, whereas patients with pancreatic gastrinomas more frequently had liver metastases. The presence of liver metastases was the most important determinant for survival. Four patients (40%) with duodenal and seven with pancreatic (50%) gastrinomas (mean follow-up 5.2 years) were biochemically cured by operation. Of the remaining patients, eight are still alive with recurrent disease. Our results suggest that preoperative localization of gastrinomas often fails despite all modern imaging methods. Therefore a standardized surgical exploration of the pancreas including IOUS and a duodenal exploration should be performed to achieve optimal results. Preoperative diagnostic imaging tests should include computed tomography, ultrasonography, and somatostatin receptor scintigraphy to exclude diffuse metastases. In contrast to liver metastases, lymph node metastases do not have a significant influence on survival.

Diagnostic Imaging↗
PubMed1998

Amitogenic alginates: key to first clinical application of microencapsulation technology.

Microencapsulation refers to a technique of immunoisolation by coating single cells or tissue with a semipermeable membrane. By combining microencapsulation with a specific tissue culturing method, iso-, allo-, and xenotransplantation of parathyroid tissue has been achieved without immunosuppression in a long-term animal model. Prior to its clinical use, continued analyses of the alginate, used as a coating substance, determined its mitogenic properties. Purification of the commercially available alginate was achieved using patented electrophoretic procedures, resulting in an amitogenic alginate suitable for use in humans. However, this alginate exhibited entirely different physical properties. We have recently shown that isotransplanted parathyroid tissue remains vital and functioning in vivo over long periods of time using the novel amitogenic alginate. It is essential to document, whether the alginate is able to maintain immunoisolation. We have therefore assessed its in vivo function compared to the mitogenic alginate in a transgenic animal model. Altogether 600 parathyroid glands from 300 Lewis rats (donor animals) were excised and subjected to tissue culture. Thereafter they were allotransplanted to 30 parathyroidectomized Dark-Auita rats, microencapsulated with the amitogenic or the mitogenic alginate or naked, with 10 recipient animals in each group. Total serum calcium and parathyroid hormone levels were monitored continuously at weekly intervals for 30 weeks. After 26 weeks the transplant beds were excised and subjected to histologic examination. More than 6 months after allotransplantation 9 of 10 animals that had received amitogenic transplants, compared to 7 of 10 animals in the group with mitogenic microcapsules were normocalcemic. Animals that had received naked parathyroid tissue were hypocalcemic as soon as 2 weeks after allotransplantation. Correspondingly, normocalcemic animals showed vital parathyroid tissue inside the microcapsules, which were surrounded by a significantly smaller rim of fibroblasts when amitogenic alginate had been used. In addition to confirming physiologic long-term function, we were able to document for the first time that immunoisolation can also be achieved with the novel amitogenic alginate, which is suitable for clinical use.

Alginates↗
PubMed1998

Hepatic-portal venous gas in acute colonic diverticulitis.

The diagnosis and assessment of severity of acute colonic diverticulitis may be difficult. A case is presented, in which the delayed diagnosis of diverticulitis resulted in the development of a diverticular mesocolic abscess complicated by hepatic-portal venous gas (HPVG). The utility of ultrasound as a rapid, noninvasive tool to diagnose this distinctly rare condition is outlined. The literature on HPVG associated with acute colonic diverticulitis is reviewed, and the therapeutic options are discussed.

Abscess↗
PubMed1998

A unique allogenic model of metastatic pheochromocytoma: PC12 rat pheochromocytoma xenografts to nude mice and establishment of metastases-derived PC12 variants.

Local invasion and metastatic spread to distant sites are major causes of death in patients with malignant pheochromocytoma. Since appropriate in vivo models do not exist, little is known about the underlying mechanisms of tumor growth and invasion. We, therefore, developed an animal model of malignant pheochromocytoma and established organotropic metastatic variants of PC12 rat pheochromocytoma cells. PC12 cells were established as xenografts to BALB/c NCR-NU mice. Subsequent to development of tumors or metastases, primary cultures from local tumors, metastases to lymph nodes, lungs and liver were established. These were subcultured in vitro and reinjected for up to five successive in vivo/in vitro cycles. Xenografted PC12 cells grew tumors with a doubling time of 6.78 +/- 0.58 days during log phase of tumor growth, killing hosts within 5-12 weeks depending on the experimental conditions. Tumors reproducibly metastasized to lymph nodes and the lung. Spontaneous metastases to the liver were not observed, but were achieved by intrasplenic injection of parent PC12 cells. In vitro, the metastatic cell lines displayed striking differences in morphology, overall growth patterns and nutritional requirements as well as binding to purified extracellular matrix proteins compared to the parent cell line. In vivo, the metastatic variants showed marked enhancement of metastatic ability. This is the first report of PC12 rat pheochromocytoma cells to exhibit the malignant phenotype in vivo. We also established variant PC12 cell lines that preferentially metastasized to specific sites and that had acquired different in vitro behavior and ability to metastasize. This unique model system should be useful for further studies relating to the invasion and metastases of pheochromocytoma and may prove valuable for investigations of novel antineoplastic therapies in vitro and in vivo.

Animals↗
PubMed1998

Influence of ultrasound on clinical decision making in acute appendicitis: a prospective study.

OBJECTIVE: To assess the efficacy of ultrasound (US) as part of an algorithm to establish the indication for laparotomy in patients with suspected acute appendicitis. DESIGN: Prospective investigation. SETTING: University department of surgery, Germany. SUBJECTS: 669 unselected patients admitted with suspected acute appendicitis. INTERVENTIONS: Clinicopathological and procedural diagnoses of the algorithm were evaluated by correlating clinical and US findings with the results of laparotomy in 171 patients of whom 143 had acute appendicitis (prevalence 21%), and clinical as well as follow up data in the remainder. MAIN OUTCOME MEASURES: The major clinicopathological variables were accuracy and positive predictive value; the rate of negative laparotomies and that of bad diagnostic errors served as the main procedural variables. RESULTS: The overall sensitivity, specificity, and accuracy of the clinical diagnosis were 0.503, 0.950, and 0.855, respectively (positive predictive value: PPV 0.734, negative predictive value: NPV 0.875), those of ultrasound: 0.797, 0.967, and 0.931 (PPV 0.870, NPV 0.946); and 0.853, 0.927, and 0.940 at the end of the algorithm (PPV 0.762, NPV 0.958). However, the algorithm would have resulted in a significant increase in the rate of unnecessary laparotomies (from 13% to 16%). A revised clinical algorithm gave an overall diagnostic accuracy of 0.940 (p < 0.001) together with a low rate of negative laparotomies (11%, p < 0.01) and a significantly reduced number of diagnostic errors (from 71 to 21, p < 0.001). CONCLUSION: Ultrasonography enabled us to diagnose acute appendicitis in more patients more often and more quickly than clinical evaluation alone, suggesting that US may produce a better outcome. The revised clinical algorithm may be helpful in the study of US in patients with suspected acute appendicitis in prospective randomised controlled clinical trials.

Acute Disease↗
PubMed1998

K-ras oncogene mutations indicate malignancy in cystic tumors of the pancreas.

OBJECTIVE: To evaluate clinical parameters, presurgical diagnostic tests, histologic findings, and the presence of K-ras oncogene mutations in cystic tumors of the pancreas to determine which best predict malignancy. SUMMARY BACKGROUND DATA: Because presurgical, intraoperative, and final pathologic differentiation is difficult in cystic tumors of the pancreas, it would be a major benefit to identify markers that accurately predict malignancy in these rare tumors. The role of K-ras oncogene mutations as an indicator of malignancy has not been determined in these tumors. METHODS: Nineteen patients with cystic tumors of the pancreas were evaluated, including K-ras mutation analysis based on polymerase chain reaction and restriction digestion assays and direct DNA sequencing, to screen for parameters that accurately predict malignancy. RESULTS: All malignant cystic pancreatic tumors (five cystadenocarcinomas and three mucin-producing adenocarcinomas) harbored K-ras mutations at codon 12 or 13. K-ras mutations were also detected in the percutaneous fine-needle aspirates of two of these patients. In contrast, none of nine benign cystadenomas or the solid-papillary neoplasm had K-ras mutations. None of the patients with a benign tumor carrying K-ras wild-type sequences developed recurrent disease after a mean follow-up of 50 months. Seven of the 8 malignant cystic pancreatic tumors, but none of the 11 benign tumors, showed dilatation of the main pancreatic duct on computed tomography or endoscopic retrograde cholangiopancreatography. CONCLUSIONS: K-ras mutation analysis seems to be a powerful tool to determine the malignant potential of cystic pancreatic tumors before and after surgery. Dilatation of the main pancreatic duct on computed tomography or endoscopic retrograde cholangiopancreatography is highly suggestive for malignancy in these rare tumors.

Adult↗
PubMed1998

MEN1 gene mutations in 12 MEN1 families and their associated tumors.

Multiple endocrine neoplasia type 1 (MEN1) is an autosomal dominant inherited tumor syndrome characterized by the development of multiple endocrine tumors. The gene responsible for the disease, termed MEN1 gene. has recently been isolated and germline mutations have been described in affected MEN1 individuals. Twelve unrelated (German MEN1 families and their associated tumors (5 parathyroid tumors, 1 vipoma, 1 gastrinoma, 1 insulinoma) were characterized for MEN1 gene mutations by single-strand conformational variant (SSCV) analysis and DNA sequence analysis as well as for loss of heterozygosity on chromosome 11q13. We identified nine different heterozygous germline mutations (6 frameshift, 2 missense, 1 nonsense), eight of them were novel. Four of five informative MEN1-associated tumors revealed deletion of the second MEN1 allele, supporting the concept of a tumor suppressor gene. Furthermore. SSCV analysis proved an effective and sensitive method for the detection of menin mutations providing a reliable genetic screening approach supporting genetic counseling and clinical management of MEN1 family members.

Adenoma↗
PubMed1998

[Laparoscopic transabdominal adrenalectomy].

Adrenalectomy is an operation, which is particularly suitable for minimally-invasive techniques. In several surgical departments with special interest in endocrine disorders laparoscopic adrenalectomy has become the procedure of choice in the surgical treatment of benign adrenal lesions. In transabdominal laparoscopic adrenalectomy the adrenal region is exposed by mobilizing the liver or the spleen respectively. The inferior vena cava and the left renal vein are the most important landmarks for further dissection and orientation. Different retroperitoneoscopic approaches have been described besides the transperitoneal techniques.

Adrenalectomy↗
PubMed1998

[Effect of perioperative antibiotic prophylaxis on hemodynamic stability during surgery: detection of complex interaction in a simulated clinical randomized animal study].

In a clinic modelling randomised trial (CMRT) in three groups of 10 land-race pietren pigs each it could be shown that the influence of prophylactic antibiotic administration on intraoperative hemodynamic stability and histamine release is only evident, if by stepwise addition of complicating factors the overall complexity of the experimental setting is increased. Different antibiotic regimen for prophylaxis significantly affected the incidence of cardiovascular instabilities only after relevant blood loss, restoration of circulation and subsequent submaximal induction of anaphylactoid reactions by the histamine liberator Polymyxin B. In conclusion, preclinical testing of therapeutic agents in complex clinic modelling randomised trials should be mandatory to avoid the possible hazards of misconducted clinical trials.

Amoxicillin-Potassium Clavulanate Combination↗
PubMed1998

[Prediction of rehabilitation outcome after surgical interventions based on biochemical parameters: a new concept in mediator research].

The perioperative changes in epinephrin-, norepinephrine-, histamin-, C5a- and interleukin-6-levels were studied in 40 patients undergoing cholecystectomy for the diagnosis of acute cholecystitis. All relevant mediator levels could be determined in 38 patients. The outcome was not optimal in 16 of them (42%). In order to evaluate the predictive value of the mediators under investigation for the quality of the patients' outcome, a model based on the Bayes' theorem was developed. Using this model the outcome (optimal vs. not optimal) could be correctly predicted in 30 (79%) of our study patients. This kind of data analysis allows to define states of increased risk for a not optimal recovery based on biochemical parameters.

Acute Disease↗
PubMed1998

[Heterologous transplantation of human parathyroid glands after microencapsulation with clinically suitable alginate : long-term function without immunosuppression in the animal model].

The role of parathyroid transplantation for the therapy of permanent hypoparathyroidism is undisputed. Because the parathyroid hormone deficiency syndromee rarely every is a vital thread to patients affected, systemic immunosuppression for transplant recipients is not justified. A technique of microencapsulation was modified for transplantation of parathyroid tissue. Using a core substance suitable for clinical use (amitogenic alginate), we accomplished allotransplantation of functioning parathyroid tissue in the long-term animal model and, very recently, reported first clinical cases without postoperative immunosuppression. In a controlled animal model of totally parathyroidectomized rats (PTX, two groups of n = 40), we investigated the ability of microencapsulation with the amitogenic alginate to enable transplantation across the highest immunological barrier (xenotransplantation: human-rat); to ensure intact transplant function and to protect from rejection. Rat parathyroid hormone (PTHRA i.S.) and serum calcium levels served as parameters of completeness of PTX; intact human PTH (PTHRA i.S.) and serum calcium levels of recipient animals were used to assess graft function. Also, tissue integrity within explanted capsules was assessed by histology. Cultured and microencapsulated parathyroid tissue resumes and maintains function in vivo, even if transplanted across the highest immunological barrier. Functionally, PTHHU i.S. replaced (PTHRA i.S.) in PTX animals entirely and restored normocalcemia. These results suggest, that xeno-transplantation of the parathyroids can be achieved without postoperative immuno-suppression in a long term animal model. These data also imply the possibility of clinical heterotransplantation of parathyroid glands.

Alginates↗
PubMed1998

[The problem of interactions in perioperative prophylaxis: reducing the risk or increasing the risk?].

Risk research and risk analysis have to be modeled as a fairly complex system including multivariate regression modeling for risk factors in etiology, Markov models in pathogenesis, and a construct of mechanistic and hermeneutic variables for clinical outcome analysis. The McPeek index is proposed as an example. Several prophylaxes for risk reduction in the perioperative period produce risk reduction as well as risk augmentation in different types of outcome. These unexpected findings were observed not only in clinical trials, but also in animal experiments and in isolated tissues. This demonstrates a basic problem of handling complexity in the real clinical setting.

Aged↗
PubMed1998

[Effect of the mortality and morbidity conference on clinical success and clinical atmosphere].

Mortality and morbidity (M and M) conferences have been presented in surgical departments in Anglo-Saxon countries for decades. In Germany, only few institutions provide a regular M + M conference. M + M conferences are part of the quality assessment within a department and follow the theory of continuous improvement. After describing a deficit in patient care, the reasons for this deficit are analyzed to avoid such a recurrence in the future. M + M conferences discuss only a minor number of complications occurring in a department compared to a prospective complications registry using a computerized data base. On the other hand, an open discussion during a M + M conference provides a good academic atmosphere within a department.

Attitude of Health Personnel↗
PubMed1997

[Results of a standardized treatment concept in primary hyperparathyroidism].

BACKGROUND AND OBJECTIVE: Primary hyperparathyroidism (PHPT) is being diagnosed ever more frequently. After diabetes mellitus, ovarian dysfunction and metabolic disorders it is now among the most frequent metabolic disease. Its surgical treatment has become standardized with increasing experience. A prospective study was undertaken to clarify to what extent our own standardized diagnostic and therapeutic measures conform to current standards in literature. PATIENTS AND METHODS: During 10 years (1. 1. 1987-31. 12. 1996) 478 patients with PHPT were treated surgically (solitary adenoma: 317 (76.5%), multiple lobe hyperplasias 66 (15.9%), double adenoma 28 (6.8%), and carcinoma 4 (0.8%). PHPT was part of the MEN (multiple endocrine neoplasia) syndrome in 20 patients. Typical symptoms of PHPT had been present in 400 patients (83.7%), while 78 (16.3%) had no manifest symptoms. Ultrasound examination of the soft tissues was the only preoperative test of localization. More extensive preoperative diagnosis was practised only before reoperations. All patients had bilateral exploration of the neck to try and demonstrate all four epithelial bodies. RESULTS: A primary operation normalized the calcium level in 405 of 414 patients (97.8%). In 64 previously unsuccessfully operated patients who were reoperated for persisting HPT the elevated calcium levels could be normalized in 90.6%. Hypercalcaemia was finally abolished in all 478 patients. Average follow-up duration for 319 patients was more than 4.8 (0.5-8.5) years. The perioperative mortality rate was 0.8 (4 of 478), with 41 deaths during the later follow-up period. Permanent recurrent laryngeal nerve palsy occurred in 6 patients (1.8%). Long-term calcium substitution was necessary postoperatively in four patients (1.2%). CONCLUSION: Our findings support a liberal policy towards indication for bilateral surgical exploration of the neck in PHPT.

Adenoma↗