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Dive into the research topics where Richard A. Prinz is active.

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Featured researches published by Richard A. Prinz.


Surgery | 1998

Total thyroidectomy for benign thyroid disease

Qiang Liu; Goldie Djuricin; Richard A. Prinz

BACKGROUND The goal of this study was to evaluate the safety and efficacy of total thyroidectomy performed for benign thyroid disease. METHODS A total of 106 consecutive patients undergoing total thyroidectomy for benign disease from October 1982 to July 1995 were reviewed. The 33 men and 73 women had an average age of 46 years (range, 16 to 82 years). Indications for total thyroidectomy were a thyroid nodule with the history of head and neck radiation in 36 patients, bilateral thyroid nodules in 35, needle biopsy of a follicular neoplasm or frozen section diagnosis of a possible malignancy in 18, and toxic goiter in 17. Total thyroidectomy was performed as the primary operation in 98 patients, and 8 patients had a completion reoperation for recurrent disease. RESULTS Pathology findings revealed benign nodular goiter in 49 patients, follicular adenoma in 26, hyperplasia in 19, and Hashimotos thyroiditis in 12. Postoperative hemorrhage requiring operative hemostasis occurred in two patients (1.9%). Two patients had unilateral recurrent laryngeal nerve (RLN) palsy before operation (1.9%). Three patients had unilateral postoperative RLN palsy (2.8%). Two cases resolved in 3 and 4 months. The only permanent RLN injury occurred in a patient reoperated for a compressive goiter. Early postoperative hypocalcemia (8.0 mg/dl or less) was found in nine patients (8.5%). No patient had permanent hypoparathyroidism at long-term follow-up evaluation. CONCLUSIONS Total thyroidectomy for benign thyroid disease can avoid reoperation for nodular goiter and hyperthyroidism and eliminate any subsequent risk of malignant change in radiated thyroid glands. A low complication rate can be achieved with meticulous surgical technique. Total thyroidectomy can be performed safely for bilateral benign thyroid disease.


American Journal of Surgery | 1988

Treatment of pancreatic cutaneous fistulas with asomatostatin analog

Richard A. Prinz; Jack Pickleman; John P. Hoffman

Five pancreatic cutaneous fistulas were treated by subcutaneous administration of a long-acting synthetic analog of somatostatin, SMS 201-995. Patients included four men and one woman who ranged in age from 52 to 77 years. The fistulas developed after drainage of a pancreatic abscess, biopsy of a pancreatic mass, splenectomies for idiopathic thrombocytopenic purpura and Feltys syndrome, and operative trauma, respectively. Fistula output consisted of 1,000 ml/day of amylase- and lipase-rich fluid in the patient with a pancreatic biopsy. The other four patients had low-output fistulas (100 to 250 ml/day) that had been draining for 1 to 12 months. Direct communication with the pancreatic duct was demonstrated by endoscopic retrograde cholangiopancreatography, sinography, or both in four of the five patients. Fistula output decreased from 340 +/- 376 ml/day to 63 +/- 36 ml/day on the first day of therapy with two daily doses of 0.05 mg SMS 201-995 (p less than 0.03) and to 13 +/- 19 ml/day on the seventh day of therapy (p less than 0.03). Two patients had prompt closure of their fistulas and one closed in 3 months. One patient with chronic pancreatitis and a duct stricture and one patient with recurring infection did not achieve permanent fistula closure with SMS 201-995. Because of its safety, ease of administration, and efficacy in decreasing fistula output, we believe somatostatin analog therapy is beneficial in hastening closure of pancreatic fistulas.


Surgery | 2003

Are there gender differences in choosing a surgical career

Theresa M Wendel; Constantine Godellas; Richard A. Prinz

BACKGROUND Interest in general surgery has declined among US medical students, with the increasing number of female medical students being cited as a causative factor. This study evaluates factors related to choosing a general surgery career and determines if they differ between men and women. METHODS A survey assessing factors that contributed to career choice was distributed to a 2002 graduating medical school class to be returned with their match lists. Students were asked, from a given list, which factors influenced their career choice. Those students who did not pursue a career in general surgery were asked what factors contributed to that decision. The results were stratified by gender. RESULTS Of 120 surveys, 54 women and 48 men responded (response rate=85%). The reason most commonly cited for a particular career choice by both men and women was the intellectual challenge of the field, chosen by 41 men (85%) and 46 women (85%). The two next most common reasons cited by male students were an elective in the field and practice lifestyle (40 of 48 respondents, or 82%, for each). Practice lifestyle was a contributing factor for 37 of the 54 women, or 69% (P=.132). The other reasons most commonly cited by women were an elective and faculty in the chosen field (46 of 54, or 85%, and 38 of 54, or 70%). Thirty-seven of the 48 men, or 77% (P=.588), felt that faculty in the field contributed to their career choice. The most commonly cited reasons for not choosing general surgery--residency lifestyle, practice lifestyle, and length of training--were the same for both groups. CONCLUSIONS Fewer women than men considered practice lifestyle in choosing their medical career. However, both men and women considered lifestyle, elective in the field of choice, and faculty important in career choice. In 2002, men and women had the same reasons for pursuing a career in general surgery or seeking another specialty.


Journal of Computer Assisted Tomography | 1983

Incidental Asymptomatic Adrenal Masses Detected by Computed Tomographic Scanning

Richard A. Prinz; Marion H. Brooks; Robert J. Churchill; John L. Graner; Ann M. Lawrence; Edward Paloyan; Mario Sparagana

Until recently, adrenal masses came to clinical attention either from local symptoms due to massive enlargement or from manifestations of excess hormones production. During the last year, an adrenal mass was identified as an incidental finding in nine patients undergoing abdominal computed tomographic (CT) scanning for unrelated problems. These five men and four women ranged in age from 41 to 73 years. Eight were hypertensive. After the CT scan, each was evaluated for catecholamine or steroid hypersecretion. Only one had clearly elevated urinary vanillylmandelic acid, metanephrine, and catecholamine levels. Equivocal evidence of catecholamine excess was seen in five patients who had slight elevation of one urinary metabolite or of plasma epinephrine or norepinephrine levels. Three patients had no evidence of medullary or cortical hyperfunction on repeated testing. Eight patients were good operative risks and underwent unilateral adrenalectomy without complication. Masses ranging in size from 1 to 4 cm were found in each. These included four cortical adenomas, two adrenal cysts, one adrenal lipoma, and one pheochromocytoma. The pheochromocytoma occurred in the patient with strong biochemical evidence of disease. With wider application of CT imaging, increasing numbers of asymptomatic adrenal masses will be detected. Care in interpreting the clinical significance of these masses and caution in recommending treatment are required.


American Journal of Surgery | 1993

Plasmid labeling confirms bacterial translocation in pancreatitis

George B. Kazantsev; David W. Hecht; Robert Rao; Ihor J. Fedorak; Paolo Gattuso; Kenneth D. Thompson; Goldie Djuricin; Richard A. Prinz

To examine whether the gut is a source of infection in acute pancreatitis, bacterial translocation and alterations of intestinal microecology and morphology were studied in 16 dogs. Dogs were colonized with a strain of Escherichia coli (E. coli 6938K) bearing the plasmid pUC4K, which confers kanamycin resistance. In eight dogs (group I), pancreatitis was induced by sodium taurocholate/trypsin injection. Eight other dogs (group II) underwent laparotomy only. The pancreas, mesenteric lymph nodes, peritoneal fluid, liver, and spleen were harvested 7 days later for culturing and histologic analysis. Identification of E. coli 6938K was accomplished by plasmid DNA analysis. Group I dogs had severe pancreatitis and ischemic changes in small bowel mucosa. Group II dogs had no changes. Translocation to the pancreas occurred in five dogs and to mesenteric lymph nodes in six dogs with pancreatitis. No translocation occurred in group II dogs (p < 0.05). In addition to E. coli 6938K, other gram-negative kanamycin-resistant species were isolated, including E. coli (other than 6938K) and Enterobacter cloacae. Enteric origin of these strains was confirmed by antibiography and plasmid DNA analysis. No overgrowth of cecal gram-negative bacteria was found. This study suggests that the gut is a primary source of infection in pancreatitis and that ischemic damage of intestinal mucosa may promote bacterial translocation.


World Journal of Surgery | 2003

Management of Biliary and Duodenal Complications of Chronic Pancreatitis

Joseph D. Vijungco; Richard A. Prinz

Biliary stricture and duodenal obstruction have been increasingly recognized as complications of chronic pancreatitis. The anatomical relationship of the distal common bile duct and the duodenum with the head of the pancreas is the main factor for their involvement in chronic pancreatitis. In hospitalized patients with pancreatitis, the incidence of biliary stricture and duodenal obstruction is reported to be about 6% and 1.2%, respectively. For patients requiring an operation for chronic pancreatitis the incidence increases to 35% for biliary stricture and 12% for duodenal obstruction. Fibrosis around the distal common bile duct can cause stenosis with obstruction of bile flow. Clinically, the presentation of these patients ranges from being asymptomatic with elevated alkaline phosphatase or bilirubin, or both, to being septic with cholangitis. Jaundice, cholangitis, hyperbilirubinemia, and persistent elevation of serum alkaline phosphatase occur more frequently in patients with pancreatitis with a biliary stricture. A twofold elevation of alkaline phosphatase is a marker of possible common duct stenosis in patients with chronic pancreatitis. The incidence of both biliary cirrhosis and cholangitis in these patients is about 10%. ERCP reveals a characteristic long, smoothly tapered stricture of the intrapancreatic common bile duct. In duodenal obstruction, the factors that convert self-limiting edema to chronic fibrosis and stricture formation are unknown, but ischemia superimposed on inflammation may be the major cause. These patients present with a prolonged history of nausea and vomiting. Barium studies typically show a long constricting lesion of the duodenum, and endoscopy reveals reactive inflammatory changes in a narrowed duodenum. Operation is indicated in patients with common bile duct strictures secondary to chronic pancreatitis when there is evidence of cholangitis, biliary cirrhosis, common duct stones, progression of stricture, elevation of alkaline phophatase and/or bilirubin for over a month, and an inability to rule out cancer. The operation of choice is either choledochoduodenostomy or choledochojejunostomy. A cholecystoenterostomy is less favored because of its higher failure rate (23%). Endoscopic stenting plays a role in patients who are unfit for surgery, but it is not recommended as definitive therapy. For duodenal obstruction, failure to resolve the obstruction with 1–2 weeks of conservative therapy is an indication for bypass. The operation of choice is a gastrojejunostomy. Not uncommonly, combined obstruction of the pancreatic duct, common bile duct, and duodenum will develop. Combined drainage procedures or resection are used to manage these problems.


American Journal of Surgery | 2001

The effect of glucagon-like peptide 2 on intestinal permeability and bacterial translocation in acute necrotizing pancreatitis

George Kouris; Qiang Liu; Heather Rossi; Goldie Djuricin; Paulo Gattuso; Catherine Nathan; Robert A. Weinstein; Richard A. Prinz

BACKGROUND Acute pancreatitis (AP) initiates a generalized inflammatory response that increases intestinal permeability and promotes bacterial translocation (BT). Impairment of the intestinal epithelial barrier is known to promote BT. Glucagon-like peptide 2 (GLP-2), a 33 residue peptide hormone, is a key regulator of the intestinal mucosa by stimulating epithelial growth. The purpose of this study was to determine whether GLP-2 decreases intestinal permeability and BT in AP. METHODS To examine whether GLP-2 can decrease intestinal permeability and thereby decrease BT in acute necrotizing pancreatitis, 34 male Sprague-Dawley rats (200 to 300 g) were studied. AP was induced in group I and group II by pressure injection of 3% taurocholate and trypsin into the common biliopancreatic duct (1 mg/kg of body weight). The potent analog to GLP-2 called ALX-0600 was utilized. Group I rats received GLP-2 analog (0.1 mg/kg, SQ, BID) and group II rats received a similar volume of normal saline as a placebo postoperatively for 3 days. Group III and group IV received GLP-2 analog and placebo, respectively. At 72 hours postoperatively, blood was drawn for culture of gram-negative organisms. Specimens from mesenteric lymph nodes (MLN), pancreas and peritoneum were harvested for culture of gram-negative bacteria. Intestinal resistance as defined by Ohms law was determined using a modified Ussing chamber to measure transepithelial current at a fixed voltage. A point scoring system for five histologic features that include intestinal edema, inflammatory cellular infiltration, fat necrosis, parenchymal necrosis, and hemorrhage was used to evaluate the severity of pancreatitis. Specimens from MLN, pancreas, jejunum, and ileum were taken for pathology. RESULTS All group I and group II rats had AP. The average transepithelial resistance in group I was 82.8 Omega/cm(2) compared with 55.9 Omega/cm(2) in group II (P <0.01). Gram-negative BT to MLN, pancreas, and peritoneum was 80%, 0%, and 0%, respectively in group I compared with 100%, 30%, and 20% translocation in group II. CONCLUSION GLP-2 treatment significantly decreases intestinal permeability in acute pancreatitis.


Journal of Gastrointestinal Surgery | 2002

Human heparanase-1 gene expression in pancreatic adenocarcinoma

Anthony W. Kim; Xiulong Xu; Edward F. Hollinger; Paolo Gattuso; Constantine Godellas; Richard A. Prinz

Extracellular matrix degradation is an essential step that allows tumor cells to penetrate a tissue barrier and become metastatic. Heparanase-1 (HPR1) is an endoglycosidase that specifically degrades heparan sulfate proteoglycans, a chief component of the extracellular matrix. HPR1 is not expressed in normal epithelial cells but can be detected in a variety of malignancies. In the present study, we examined HPR1 expression in pancreatic cancer by using in situ hybridization and tested whether HPR1 expression correlated with any clinicopathlogic parameters. HPR1 was not detected in the ductal cells of normal pancreas samples obtained from 10 patients at autopsy. However, HPR1 was detected in 77 (78%) of 99 panceatic adenocarcinomas. Among them, 69 (78%) of 89 primary pancreatic adenocarcinomas and 8 (80%) of the 10 metastases were HPR1 positive. Age, sex, tumor stage, and lymph node status were not predictive of HPR1 expression. Log-rank test of the Kaplan-Meier survival curves revealed that HPR1 expression in early-stage tumors was associated with decreased survival. HPR1 expression was frequent in pancreatic adenocarcinomas and was associated with decreased survival in early-stage tumors. This suggests that HPR1 may contribute to the highly invasive and early metastatic behavior of pancreatic cancer.


Journal of The American College of Surgeons | 2015

Early National Experience with Laparoscopic Pancreaticoduodenectomy for Ductal Adenocarcinoma: A Comparison of Laparoscopic Pancreaticoduodenectomy and Open Pancreaticoduodenectomy from the National Cancer Data Base

Susan M. Sharpe; Mark S. Talamonti; Chihsiung E. Wang; Richard A. Prinz; Kevin K. Roggin; David J. Bentrem; David J. Winchester; Robert de Wilton Marsh; Susan J. Stocker; Marshall S. Baker

BACKGROUND There is considerable debate about the safety and clinical equivalence of laparoscopic pancreaticoduodenectomy (LPD) and open pancreaticoduodenectomy (OPD) for pancreatic ductal adenocarcinoma (PDCA). STUDY DESIGN We queried the National Cancer Data Base to identify patients undergoing LPD and OPD for PDCA between 2010 and 2011. Chi-square and Students t-tests were used to evaluate differences between the 2 approaches. Multivariable logistic regression modeling was performed to identify patient, tumor, or facility factors associated with perioperative mortality. RESULTS Four thousand and thirty-seven (91%) patients underwent OPD. Three hundred and eighty-four (9%) patients underwent LPD. There were no statistical differences between the 2 surgical cohorts with regard to age, race, Charlson score, tumor size, grade, stage, or treatment with neoadjuvant chemoradiotherapy. Laparoscopic pancreaticoduodenectomy demonstrated a shorter length of stay (10 ± 8 days vs 12 ± 9.7 days; p < 0.0001) and lower rates of unplanned readmission (5% vs 9%; p = 0.027) than OPD. In an unadjusted comparison, there was no difference in 30-day mortality between the LPD and OPD cohorts (5.2% vs 3.7%; p = 0.163). Multivariable logistic regression modeling predicting perioperative mortality controlling for age, Charlson score, tumor size, nodal positivity, stage, facility type, and pancreaticoduodenectomy volume identified age (odds ratio [OR] = 1.05; p < 0.0001), positive margins (OR = 1.45; p = 0.030), and LPD (OR = 1.89; p = 0.009) as associated with an increased probability of 30-day mortality; higher hospital volume was associated with a lower risk of 30-day mortality (OR = 0.98; p < 0.0001). In institutions that performed ≥10 LPDs, the 30-day mortality rate of the laparoscopic approach was equal to that for the open approach (0.0% vs 0.7%; p = 1.00). CONCLUSIONS Laparoscopic pancreaticoduodenectomy is equivalent to OPD in length of stay, margin-positive resection, lymph node count, and readmission rate. There is a higher 30-day mortality rate with LPD, but this appears driven by a surmountable learning curve for the procedure.


Surgical Clinics of North America | 1995

Selection of Patients with Adrenal Incidentalomas for Operation

Edgar D. Staren; Richard A. Prinz

An adrenal mass may be discovered incidentally in as many as 2% of patients having an abdominal CT scan. The clinical dilemma is to identify the rare functioning or malignant adrenal tumor, which warrants resection, while avoiding unnecessary testing and surgery in the majority of patients whose adrenal lesions are nonfunctioning and benign. A thorough history and physical examination and judicious use of screening laboratory tests are important in determining the likelihood of a clinically significant adrenal mass. There is little debate that functional or large (< 6 cm) adrenal masses should be excised; adrenalectomy for adrenal masses 3 to 6 cm in patients younger than 50 years of age and for those masses with ominous CT characteristics also is advised. Observation with serial CT scans and screening studies are recommended for patients 50 years of age or older whose adrenal masses are between 3 to 6 cm and for all patients with hormonally inactive masses that are smaller than 3 cm.

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David J. Winchester

NorthShore University HealthSystem

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Xiulong Xu

Rush University Medical Center

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Paolo Gattuso

Rush University Medical Center

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Mark S. Talamonti

NorthShore University HealthSystem

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Marshall S. Baker

NorthShore University HealthSystem

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Tricia A. Moo-Young

NorthShore University HealthSystem

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Roderick M. Quiros

Rush University Medical Center

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Goldie Djuricin

Rush University Medical Center

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