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Dive into the research topics where Timothy L. Pruett is active.

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Featured researches published by Timothy L. Pruett.


The New England Journal of Medicine | 1995

Hepatic Failure and Lactic Acidosis Due to Fialuridine (FIAU), an Investigational Nucleoside Analogue for Chronic Hepatitis B

Robin McKenzie; Michael W. Fried; Richard Sallie; Hari Conjeevaram; Adrian M. di Bisceglie; Yoon Park; Barbara Savarese; David E. Kleiner; Maria Tsokos; Carlos Luciano; Timothy L. Pruett; Jennifer L. Stotka; Stephen E. Straus; Jay H. Hoofnagle

BACKGROUND We describe severe and unexpected multisystem toxicity that occurred during a study of the antiviral nucleoside analogue fialuridine (1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)-5-iodouracil, or FIAU) as therapy for chronic hepatitis B virus infection. METHODS Fifteen patients with chronic hepatitis B were randomly assigned to receive fialuridine at a dose of either 0.10 or 0.25 mg per kilogram of body weight per day for 24 weeks and were monitored every 1 to 2 weeks by means of a physical examination, blood tests, and testing for hepatitis B virus markers. RESULTS During the 13th week lactic acidosis and liver failure suddenly developed in one patient. The study was terminated on an emergency basis, and all treatment with fialuridine was discontinued. Seven patients were found to have severe hepatotoxicity, with progressive lactic acidosis, worsening jaundice, and deteriorating hepatic synthetic function despite the discontinuation of fialuridine. Three other patients had mild hepatotoxicity. Several patients also had pancreatitis, neuropathy, or myopathy. Of the seven patients with severe hepatotoxicity, five died and two survived after liver transplantation. Histologic analysis of liver tissue revealed marked accumulation of microvesicular and macrovesicular fat, with minimal necrosis of hepatocytes or architectural changes. Electron microscopy showed abnormal mitochondria and the accumulation of fat in hepatocytes. CONCLUSIONS In patients with chronic hepatitis B, treatment with fialuridine induced a severe toxic reaction characterized by hepatic failure, lactic acidosis, pancreatitis, neuropathy, and myopathy. This toxic reaction was probably caused by widespread mitochondrial damage and may occur infrequently with other nucleoside analogues.


The New England Journal of Medicine | 1992

A Controlled Trial of Scheduled Replacement of Central Venous and Pulmonary-Artery Catheters

David K. Cobb; Kevin P. High; Robert G. Sawyer; Carole A. Sable; Reid B. Adams; Dwight A. Lindley; Timothy L. Pruett; Karen J. Schwenzer; Barry M. Farr

Abstract Background. The incidence of infection increases with the prolonged use of central vascular catheters, but it is unclear whether changing catheters every three days, as some recommend, will reduce the rate of infection. It is also unclear whether it is safer to change a catheter over a guide wire or insert it at a new site. Methods. We conducted a controlled trial in adult patients in intensive care units who required central venous or pulmonary-artery catheters for more than three days. Patients were assigned randomly to undergo one of four methods of catheter exchange: replacement every three days either by insertion at a new site (group 1) or by exchange over a guide wire (group 2), or replacement when clinically indicated either by insertion at a new site (group 3) or by exchange over a guide wire (group 4). Results. Of the 160 patients, 5 percent had catheter-related bloodstream infections, 16 percent had catheters that became colonized, and 9 percent had major mechanical complications. The ...


Gastroenterology | 2008

Donor Morbidity After Living Donation for Liver Transplantation

Rafik M. Ghobrial; Chris E. Freise; James F. Trotter; Lan Tong; Akinlolu Ojo; Jeffrey H. Fair; Robert A. Fisher; Jean C. Emond; Alan J. Koffron; Timothy L. Pruett; Kim M. Olthoff

BACKGROUND & AIMS Reports of complications among adult right hepatic lobe donors have been limited to single centers. The rate and severity of complications in living donors were investigated in the 9-center Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL). METHODS A retrospective observational study design was used. Participants included all potential living donors evaluated between 1998 and 2003. Complication severity was graded using the Clavien scoring system. RESULTS Of 405 donors accepted for donation, 393 underwent donation, and 12 procedures were aborted. There were 245 donors (62%) who did not experience complications; 82 (21%) had 1 complication, and 66 (17%) had 2 or more. Complications were scored as grade 1 (minor; n = 106, 27%), grade 2 (potentially life threatening; n = 103, 26%), grade 3 (life threatening; n = 8, 2%), and grade 4 (leading to death; n = 3, 0.8%). Common complications included biliary leaks beyond postoperative day 7 (n = 36, 9%), bacterial infections (n = 49, 12%), incisional hernia (n = 22, 6%), pleural effusion requiring intervention (n = 21, 5%), neuropraxia (n = 16, 4%), reexploration (n = 12, 3%), wound infections (n = 12, 3%), and intraabdominal abscess (n = 9, 2%). Two donors developed portal vein thrombosis, and 1 had inferior vena caval thrombosis. Fifty-one (13%) donors required hospital readmission, and 14 (4%) required 2 to 5 readmissions. CONCLUSIONS Adult living liver donation was associated with significant donor complications. Although most complications were of low-grade severity, a significant proportion were severe or life threatening. Quantification of complication risk may improve the informed consent process, perioperative planning, and donor care.


Clinical Infectious Diseases | 2003

Opportunistic Mycelial Fungal Infections in Organ Transplant Recipients: Emerging Importance of Non-Aspergillus Mycelial Fungi

Shahid Husain; Barbara D. Alexander; Patricia Muñoz; Robin K. Avery; Sally Houston; Timothy L. Pruett; Richard Jacobs; Edward A. Dominguez; Jan Tollemar; Katherine Baumgarten; Chen M. Yu; Marilyn M. Wagener; Peter K. Linden; Shimon Kusne; Nina Singh

To determine the spectrum and impact of mycelial fungal infections, particularly those due to non-Aspergillus molds, 53 liver and heart transplant recipients with invasive mycelial infections were prospectively identified in a multicenter study. Invasive mycelial infections were due to Aspergillus species in 69.8% of patients, to non-Aspergillus hyalohyphomycetes in 9.4%, to phaeohyphomycetes in 9.4%, to zygomycetes in 5.7%, and to other causes in 5.7%. Infections due to mycelial fungi other than Aspergillus species were significantly more likely to be associated with disseminated (P=.005) and central nervous system (P=.07) infection than were those due to Aspergillus species. Overall mortality at 90 days was 54.7%. The associated mortality rate was 100% for zygomycosis, 80% for non-Aspergillus hyalohyphomycosis, 54% for aspergillosis, and 20% for phaeohyphomycosis. Thus, non-Aspergillus molds have emerged as significant pathogens in organ transplant recipients. These molds are more likely to be associated with disseminated infections and to be associated with poorer outcomes than is aspergillosis.


Transplantation | 1996

Improved outcome of orthotopic liver transplantation for chronic hepatitis B cirrhosis with aggressive passive immunization

Robert W. McGory; Michael B. Ishitani; Walter Oliveira; William C. Stevenson; Christopher McCullough; Rolland C. Dickson; Stephen H. Caldwell; Timothy L. Pruett

Passive immunization with hepatitis B surface antibody (anti-HBs) is important to prevent hepatitis B virus (HBV) recurrence after orthotopic liver transplantation for chronic HBV cirrhosis. Hepatitis B immune globulin (HBIG) dosing regimens have been poorly defined, utilize numerous routes of administration, and result in a high rate of HBV relapse and mortality. Twenty-five of 27 (93%) patients transplanted (four retransplants) for chronic HBV cirrhosis show no evidence of recurrent HBV (range, 2-55 months). Anti-HBs titers necessary to minimize the risk of hepatitis B surface antigen detectability were >500 IU/L for days 0 to 7, >250 IU/L for days 8 to 90, and >100 IU/L thereafter. Pretransplant HBV E antigen (HBeAG)-positive patients required more HBIG to achieve these goals than HBeAG-negative individuals. The elimination of anti-HBs changed continually for the initial 3 posttransplant months. The anti-HBs half-life increased from 0.7 days to 14.1 days. Anti-HBs elimination was significantly different in HBeAG+ and HBeAG- patients for the first week, but was subsequently indistinguishable after week 1. After 3 months, the half-life was statistically less for HBeAG+ patients, but the difference did not influence the clinical treatment regimens. Quantitative hepatitis B DNA levels did not predict the amount of HBIG required. HBV recurrence after orthotopic liver transplantation can be reduced by aggressive passive immunization. Pharmacokinetic analysis of anti-Hbs elimination can improve immunoglobulin therapy and prevent recurrence of clinical hepatitis.


Annals of Surgery | 2005

OUTCOMES OF 385 ADULT-TO-ADULT LIVING DONOR LIVER TRANSPLANT RECIPIENTS: A REPORT FROM THE A2ALL CONSORTIUM

Kim M. Olthoff; Robert M. Merion; Rafik M. Ghobrial; Michael Abecassis; Jeffrey H. Fair; Robert A. Fisher; Chris E. Freise; Igal Kam; Timothy L. Pruett; James E. Everhart; Tempie E. Hulbert-Shearon; Brenda W. Gillespie; Jean C. Emond; Charles M. Miller; Raymond Pollak; Charles B. Huddleston; Nancy L. Ascher; Byers W. Shaw; Robert M. Mentzer

Objective:The objective of this study was to characterize the patient population with respect to patient selection, assess surgical morbidity and graft failures, and analyze the contribution of perioperative clinical factors to recipient outcome in adult living donor liver transplantation (ALDLT). Summary Background Data:Previous reports have been center-specific or from large databases lacking detailed variables. The Adult-to-Adult Living Donor Liver Transplantation Cohort Study (A2ALL) represents the first detailed North American multicenter report of recipient risk and outcome aiming to characterize variables predictive of graft failure. Methods:Three hundred eighty-five ALDLT recipients transplanted at 9 centers were studied with analysis of over 35 donor, recipient, intraoperative, and postoperative variables. Cox regression models were used to examine the relationship of variables to the risk of graft failure. Results:Ninety-day and 1-year graft survival were 87% and 81%, respectively. Fifty-one (13.2%) grafts failed in the first 90 days. The most common causes of graft failure were vascular thrombosis, primary nonfunction, and sepsis. Biliary complications were common (30% early, 11% late). Older recipient age and length of cold ischemia were significant predictors of graft failure. Center experience greater than 20 ALDLT was associated with a significantly lower risk of graft failure. Recipient Model for End-stage Liver Disease score and graft size were not significant predictors. Conclusions:This multicenter A2ALL experience provides evidence that ALDLT is a viable option for liver replacement. Older recipient age and prolonged cold ischemia time increase the risk of graft failure. Outcomes improve with increasing center experience.


American Journal of Transplantation | 2009

ASTS recommended practice guidelines for controlled donation after cardiac death organ procurement and transplantation

David J. Reich; David C. Mulligan; Peter L. Abt; Timothy L. Pruett; Michael Abecassis; Anthony M. D'Alessandro; Elizabeth A. Pomfret; Richard B. Freeman; James F. Markmann; Douglas W. Hanto; Arthur J. Matas; John P. Roberts; Robert M. Merion; Goran B. Klintmalm

The American Society of Transplant Surgeons (ASTS) champions efforts to increase organ donation. Controlled donation after cardiac death (DCD) offers the family and the patient with a hopeless prognosis the option to donate when brain death criteria will not be met. Although DCD is increasing, this endeavor is still in the midst of development. DCD protocols, recovery techniques and organ acceptance criteria vary among organ procurement organizations and transplant centers. Growing enthusiasm for DCD has been tempered by the decreased yield of transplantable organs and less favorable posttransplant outcomes compared with donation after brain death. Logistics and ethics relevant to DCD engender discussion and debate among lay and medical communities. Regulatory oversight of the mandate to increase DCD and a recent lawsuit involving professional behavior during an attempted DCD have fueled scrutiny of this activity. Within this setting, the ASTS Council sought best‐practice guidelines for controlled DCD organ donation and transplantation. The proposed guidelines are evidence based when possible. They cover many aspects of DCD kidney, liver and pancreas transplantation, including donor characteristics, consent, withdrawal of ventilatory support, operative technique, ischemia times, machine perfusion, recipient considerations and biliary issues. DCD organ transplantation involves unique challenges that these recommendations seek to address.


Critical Care Medicine | 2001

Impact of a rotating empiric antibiotic schedule on infectious mortality in an intensive care unit

Daniel P. Raymond; Shawn J. Pelletier; Traves D. Crabtree; Thomas G. Gleason; Lori L. Hamm; Timothy L. Pruett; Robert G. Sawyer

Objective The development of antibiotic-resistant bacteria is associated with significant morbidity and mortality in critically ill patients. We postulated that quarterly rotation of empirical antibiotics could decrease infectious complications from resistant organisms in an intensive care unit (ICU). Design Prospective cohort study. Setting An ICU at a university medical center. Subjects All patients admitted to the general, transplant, or trauma surgery services who developed pneumonia, peritonitis, or sepsis of unknown origin. Interventions A 2-yr study consisting of 1 yr of nonprotocol-driven antibiotic use and 1 yr of rotating empirical antibiotic assignment. Measurements and Main Results Over 100 variables were recorded for each infectious episode, including patient characteristics (e.g., Acute Physiology and Chronic Health Evaluation [APACHE] II score, age, comorbidities), infection characteristics (e.g., site, organism), treatment characteristics (e.g., antibiotic, treatment duration) and outcome measures (e.g., mortality, length of stay, antibiotic cost). Of 1456 consecutive admissions to the ICU, 540 episodes of infection were treated. No differences were noted in age, APACHE II score, race, overall antibiotic utilization or duration of therapy between the 2 yrs of study. Outcome analysis revealed significant reductions in the incidence of antibiotic-resistant Gram-positive coccal infections (7.8 infections/100 admissions vs. 14.6 infections/100 admissions, p < .0001), antibiotic-resistant Gram-negative bacillary infections (2.5 infections/100 admissions vs. 7.7 infections/100 admissions, p < .0001), and mortality associated with infection (2.9 deaths/100 admissions vs. 9.6 deaths/100 admissions, p < .0001) during rotation. Logistic regression identified age (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.01–1.06), APACHE II score (OR, 1.06; 95% CI, 1.01–1.13), solid organ transplantation (OR, 9.50; 95% CI, 2.01–52.21), and malignancy (OR, 10.16; 95% CI, 4.11–26.96) as independent predictors of mortality. Antibiotic rotation was an independent predictor of survival (OR 6.27, 95% CI 2.78–14.16). Conclusion Rotation of empirical antibiotic therapy seems to be a promising method to reduce infectious mortality in an ICU.


Journal of The American College of Surgeons | 2012

Total Pancreatectomy and Islet Autotransplantation for Chronic Pancreatitis

David E. R. Sutherland; David M. Radosevich; Melena D. Bellin; B. J. Hering; Gregory J. Beilman; Ty B. Dunn; Srinath Chinnakotla; Selwyn M. Vickers; Barbara Bland; A. N. Balamurugan; Martin L. Freeman; Timothy L. Pruett

BACKGROUND Total pancreatectomy (TP) with intraportal islet autotransplantation (IAT) can relieve pain and preserve β-cell mass in patients with chronic pancreatitis (CP) when other therapies fail. We report on a >30-year single-center series. STUDY DESIGN Four hundred and nine patients (including 53 children, 5 to 18 years) with CP underwent TP-IAT from February 1977 to September 2011 (etiology: idiopathic, 41%; Sphincter of Oddi dysfunction/biliary, 9%; genetic, 14%; divisum, 17%; alcohol, 7%; and other, 12%; mean age was 35.3 years, 74% were female; 21% has earlier operations, including 9% Puestow procedure, 6% Whipple, 7% distal pancreatectomy, and 2% other). Islet function was classified as insulin independent for those on no insulin; partial, if known C-peptide positive or euglycemic on once-daily insulin; and insulin dependent if on standard basal-bolus diabetic regimen. A 36-item Short Form (SF-36) survey for quality of life was completed by patients before and in serial follow-up since 2007, with an integrated survey that was added in 2008. RESULTS Actuarial patient survival post TP-IAT was 96% in adults and 98% in children (1 year) and 89% and 98% (5 years). Complications requiring relaparotomy occurred in 15.9% and bleeding (9.5%) was the most common complication. IAT function was achieved in 90% (C-peptide >0.6 ng/mL). At 3 years, 30% were insulin independent (25% in adults, 55% in children) and 33% had partial function. Mean hemoglobin A1c was <7.0% in 82%. Earlier pancreas surgery lowered islet yield (2,712 vs 4,077/kg; p = 0.003). Islet yield (<2,500/kg [36%]; 2,501 to 5,000/kg [39%]; >5,000/kg [24%]) correlated with degree of function with insulin-independent rates at 3 years of 12%, 22%, and 72%, and rates of partial function 33%, 62%, and 24%. All patients had pain before TP-IAT and nearly all were on daily narcotics. After TP-IAT, 85% had pain improvement. By 2 years, 59% had ceased narcotics. All children were on narcotics before, 39% at follow-up; pain improved in 94%; and 67% became pain-free. In the SF-36 survey, there was significant improvement from baseline in all dimensions, including the Physical and Mental Component Summaries (p < 0.01), whether on narcotics or not. CONCLUSIONS TP can ameliorate pain and improve quality of life in otherwise refractory CP patients, even if narcotic withdrawal is delayed or incomplete because of earlier long-term use. IAT preserves meaningful islet function in most patients and substantial islet function in more than two thirds of patients, with insulin independence occurring in one quarter of adults and half the children.


Clinical Infectious Diseases | 2005

An immune reconstitution syndrome-like illness associated with Cryptococcus neoformans infection in organ transplant recipients.

Nina Singh; Olivier Lortholary; Barbara D. Alexander; Krishan L. Gupta; George T. John; Kenneth Pursell; Patricia Muñoz; Goran B. Klintmalm; Valentina Stosor; Ramon Del Busto; Ajit P. Limaye; Jyoti Somani; Marshall Lyon; Sally Houston; Andrew A. House; Timothy L. Pruett; Susan L. Orloff; Atul Humar; Lorraine A. Dowdy; Julia Garcia-Diaz; Andre C. Kalil; Robert A. Fisher; Shahid Husain

BACKGROUND We describe an immune reconstitution syndrome (IRS)-like entity in the course of evolution of Cryptococcus neoformans infection in organ transplant recipients. METHODS The study population comprised a cohort of 83 consecutive organ transplant recipients with cryptococcosis who were observed for a median of 2 years in an international, multicenter study. RESULTS In 4 (4.8%) of the 83 patients, an IRS-like entity was observed a median of 5.5 weeks after the initiation of appropriate antifungal therapy. Worsening of clinical manifestations was documented, despite cultures being negative for C. neoformans. These patients were significantly more likely to have received tacrolimus, mycophenolate mofetil, and prednisone as the regimen of immunosuppressive therapy than were all other patients (P = .007). The proposed basis of this phenomenon is reversal of a predominantly Th2 response at the onset of infection to a Th1 proinflammatory response as a result of receipt of effective antifungal therapy and a reduction in or cessation of immunosuppressive therapy. CONCLUSIONS This study demonstrated that an IRS-like entity occurs in organ transplant recipients with C. neoformans infection. Furthermore, this entity may be misconstrued as a failure of therapy. Immunomodulatory agents may have a role as adjunctive therapy in such cases.

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Ty B. Dunn

University of Minnesota

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