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Featured researches published by R. Todd Stravitz.


Hepatology | 2004

Persistent ascites and low serum sodium identify patients with cirrhosis and low MELD scores who are at high risk for early death

Douglas M. Heuman; Souheil G. Abou-Assi; Adil Habib; Leslie M. Williams; R. Todd Stravitz; Arun J. Sanyal; Robert A. Fisher; Anastasios A. Mihas

Despite the adoption of “sickest first” liver transplantation, pretransplant death remains common, and many early deaths occur despite initially low Model for End‐stage Liver Disease (MELD) scores. From 1997–2003, we studied 507 cirrhotic United States veterans referred for consideration of liver transplantation to identify additional predictors of early mortality. Most of the patients were male (98%) with cirrhosis caused by hepatitis C and/or alcohol (88%). Data for 296 patients referred prior to February 27, 2002 (training group), were analyzed; findings were validated in 211 patients referred subsequently (validation group). In the training group, 61 patients (21%) died within 180 days without transplantation; their median initial MELD score was 21. MELD score, persistent ascites, and low serum sodium (<135 meq/L) were independent predictors of early mortality. In patients with a MELD score of less than 21, only low serum sodium and persistent ascites were independent predictors of mortality; for MELD scores above 21, only MELD was independently predictive. Prognostic significance of persistent ascites and low serum sodium for low MELD score patients was confirmed in the validation group. Risk varied continuously with worsening hyponatremia. Modifying MELD, by including points for persistent ascites and low serum sodium, improved prediction of early pretransplant mortality in low MELD score patients. In conclusion, persistent ascites and low serum sodium identify patients with cirrhosis with high mortality risk despite low MELD scores. Ascites, hyponatremia, and other findings indicative of hemodynamic decompensation merit further prospective study as prognostic indicators in patients awaiting liver transplantation, and should be considered in setting minimal listing criteria. Supplementary material for this article can be found on the HEPATOLOGYwebsite (http://interscience.wiley.com/jpages/0270‐9139/suppmat/index.html). (HEPATOLOGY 2004;40:802–810.)


Clinical Gastroenterology and Hepatology | 2004

A pilot study of vitamin E versus vitamin E and pioglitazone for the treatment of nonalcoholic steatohepatitis

Arun J. Sanyal; Pouneh S. Mofrad; Melissa J. Contos; Carol Sargeant; Velimir A. Luketic; Richard K. Sterling; R. Todd Stravitz; Mitchell L. Shiffman; John N. Clore; A.S. Mills

BACKGROUND & AIMS Insulin resistance and oxidative stress contribute to the pathogenesis of nonalcoholic steatohepatitis (NASH). We conducted a pilot study for the following reasons: (1) to test the hypothesis that a combination of an antioxidant (vitamin E) and an insulin sensitizer (pioglitazone) would be superior to vitamin E alone for the treatment of NASH, and (2) to define the effects of these interventions on insulin-sensitive metabolic functions and correlate the effects with changes in liver histology. METHODS A randomized prospective trial was performed to compare the efficacy and safety of vitamin E alone (400 IU/day) vs. vitamin E (400 IU/day) and pioglitazone (30 mg/day) in nondiabetic, noncirrhotic subjects with NASH. Metabolic functions were assessed by a 2-step, hyperinsulinemic (10 and 40 mU/m2/min) euglycemic clamp. RESULTS A total of 10 patients were randomized to each arm. Two patients on combination therapy discontinued treatment; one because of pregnancy and the other because of hepatotoxicity. Treatment with vitamin E only produced a significant decrease in steatosis (mean grade, 2.2 vs. 1.4; P < .02). Compared with baseline, combination therapy produced a significant decrease in steatosis (mean, 2.3 vs. 1; P < .002), cytologic ballooning (1.3 vs. 0.2; P < .01), Mallorys hyaline (0.7 vs. 0.2; P < .04), and pericellular fibrosis (1.2 vs. 0.6; P < .03). Although vitamin E had no significant effects, combination therapy produced a significant increase in metabolic clearance of glucose and a decrease in fasting free fatty acid (FFA) and insulin. The decrease in fasting FFA and insulin independently predicted improvement in hepatic steatosis and cytologic ballooning. CONCLUSIONS A combination of vitamin E and pioglitazone produces a greater improvement in NASH histology. The improvement in steatosis and cytologic ballooning are related to treatment-associated decreases in fasting FFA and insulin levels.


Gastroenterology | 2009

Intravenous N-acetylcysteine improves transplant-free survival in early stage non-acetaminophen acute liver failure.

William M. Lee; Linda S. Hynan; Lorenzo Rossaro; Robert J. Fontana; R. Todd Stravitz; Anne M. Larson; Timothy J. Davern; Natalie Murray; Timothy M. McCashland; Joan S. Reisch; Patricia R. Robuck

BACKGROUND & AIMS N-acetylcysteine (NAC), an antidote for acetaminophen poisoning, might benefit patients with non-acetaminophen-related acute liver failure. METHODS In a prospective, double-blind trial, acute liver failure patients without clinical or historical evidence of acetaminophen overdose were stratified by site and coma grade and assigned randomly to groups that were given NAC or placebo (dextrose) infusion for 72 hours. The primary outcome was overall survival at 3 weeks. Secondary outcomes included transplant-free survival and rate of transplantation. RESULTS A total of 173 patients received NAC (n = 81) or placebo (n = 92). Overall survival at 3 weeks was 70% for patients given NAC and 66% for patients given placebo (1-sided P = .283). Transplant-free survival was significantly better for NAC patients (40%) than for those given placebo (27%; 1-sided P = .043). The benefits of transplant-free survival were confined to the 114 patients with coma grades I-II who received NAC (52% compared with 30% for placebo; 1-sided P = .010); transplant-free survival for the 59 patients with coma grades III-IV was 9% in those given NAC and 22% in those given placebo (1-sided P = .912). The transplantation rate was lower in the NAC group but was not significantly different between groups (32% vs 45%; P = .093). Intravenous NAC generally was well tolerated; only nausea and vomiting occurred significantly more frequently in the NAC group (14% vs 4%; P = .031). CONCLUSIONS Intravenous NAC improves transplant-free survival in patients with early stage non-acetaminophen-related acute liver failure. Patients with advanced coma grades do not benefit from NAC and typically require emergency liver transplantation.


Critical Care Medicine | 2007

Intensive care of patients with acute liver failure: Recommendations of the U.S. Acute Liver Failure Study Group

R. Todd Stravitz; Andreas H. Kramer; Timothy J. Davern; A. Obaid S Shaikh; Stephen H. Caldwell; Ravindra L. Mehta; Andres T. Blei; Robert J. Fontana; Brendan M. McGuire; Lorenzo Rossaro; Alastair D. Smith; William M. Lee

Objective:To provide a uniform platform from which to study acute liver failure, the U.S. Acute Liver Failure Study Group has sought to standardize the management of patients with acute liver failure within participating centers. Methods:In areas where consensus could not be reached because of divergent practices and a paucity of studies in acute liver failure patients, additional information was gleaned from the intensive care literature and literature on the management of intracranial hypertension in non-acute liver failure patients. Experts in diverse fields were included in the development of a standard study-wide management protocol. Measurements and Main Results:Intracranial pressure monitoring is recommended in patients with advanced hepatic encephalopathy who are awaiting orthotopic liver transplantation. At an intracranial pressure of ≥25 mm Hg, osmotic therapy should be instituted with intravenous mannitol boluses. Patients with acute liver failure should be maintained in a mildly hyperosmotic state to minimize cerebral edema. Accordingly, serum sodium should be maintained at least within high normal limits, but hypertonic saline administered to 145–155 mmol/L may be considered in patients with intracranial hypertension refractory to mannitol. Data are insufficient to recommend further therapy in patients who fail osmotherapy, although the induction of moderate hypothermia appears to be promising as a bridge to orthotopic liver transplantation. Empirical broad-spectrum antibiotics should be administered to any patient with acute liver failure who develops signs of the systemic inflammatory response syndrome, or unexplained progression to higher grades of encephalopathy. Other recommendations encompassing specific hematologic, renal, pulmonary, and endocrine complications of acute liver failure patients are provided, including their management during and after orthotopic liver transplantation. Conclusions:The present consensus details the intensive care management of patients with acute liver failure. Such guidelines may be useful not only for the management of individual patients with acute liver failure, but also to improve the uniformity of practices across academic centers for the purpose of collaborative studies.


Journal of Hepatology | 2010

Hemostasis and thrombosis in patients with liver disease: The ups and downs

Ton Lisman; Stephen H. Caldwell; Andrew K. Burroughs; Patrick G. Northup; Marco Senzolo; R. Todd Stravitz; Armando Tripodi; James F. Trotter; D. Valla; Robert J. Porte

Patients with chronic or acute liver failure frequently show profound abnormalities in their hemostatic system. Whereas routine laboratory tests of hemostasis suggest these hemostatic alterations result in a bleeding diathesis, accumulating evidence from both clinical and laboratory studies suggest that the situation is more complex. The average patient with liver failure may be in hemostatic balance despite prolonged routine coagulation tests, since both pro- and antihemostatic factors are affected, the latter of which are not well reflected in routine coagulation testing. However, this balance may easily tip towards a hypo- or hypercoagulable situation. Indeed, patients with liver disease may encounter both hemostasis-related bleeding episodes as well as thrombotic events. During the 3rd International Symposium on Coagulopathy and Liver disease, held in Groningen, The Netherlands (18-19 September 2009), a multidisciplinary panel of experts critically reviewed the current data concerning pathophysiology and clinical consequences of hemostatic disorders in patients with liver disease. Highlights of this symposium are summarized in this review.


Hepatology | 2007

Treatment of chronic hepatitis C virus genotype 1 with peginterferon, ribavirin, and epoetin alpha

Mitchell L. Shiffman; Jennifer Salvatore; Sarah Hubbard; Angie Price; Richard K. Sterling; R. Todd Stravitz; Velimir A. Luketic; Arun J. Sanyal

Successful treatment of chronic HCV with peginterferon (PEGIFN) and ribavirin (RVN) is often limited by anemia. We performed the present study to determine if utilizing epoetin alpha (EPO) with or without a higher dose of RVN could enhance sustained virologic response (SVR). We randomized 150 treatment‐naive patients with chronic HCV genotype 1 into 3 treatment groups: (1) PEGIFN alpha‐2b (1.5 μg/kg/week) + weight‐based RVN (WBR) 13.3 mg/kg/day (800 to 1400 mg/day); (2) PEGIFN alpha‐2b + WBRVN + EPO (40,000 U/week); or (3) PEGIFN alpha‐2b + higher dose WBR 15.2 mg/kg/day (1000 to 1600 mg/day) + EPO. We initiated EPO at the onset of therapy to maintain the hemoglobin between 12 and 15 g/dL. When required, we reduced RVN by 200‐mg steps. African Americans compose 36% of the population. A significantly smaller percentage of group 2 patients had a decline in hemoglobin to less than 10 g/dL (9% versus 34%; P < 0.05) and required that the RVN dose be reduced (10% versus 40%; P < 0.05) compared to group 1 patients. Despite this, SVR was similar in these groups (19% to 29%). SVR was significantly greater (P < 0.05) in group 3 patients (49%). This resulted from a significant decline (P < 0.05) in relapse rate; only 8% versus 38% for groups 1 and 2. Conclusion: We conclude that using EPO in all subjects at the initiation of PEGIFN and RVN treatment will not enhance SVR given the same starting dose of RVN. In contrast, a higher starting dose of RVN was associated with a lower relapse rate and higher rate of SVR. (HEPATOLOGY 2007.)


Hepatology | 2009

Minimal hepatic encephalopathy is associated with motor vehicle crashes: the reality beyond the driving test.

Jasmohan S. Bajaj; Kia Saeian; Christine M. Schubert; Muhammad Hafeezullah; Jose Franco; Rajiv R. Varma; Douglas P. Gibson; Raymond G. Hoffmann; R. Todd Stravitz; Douglas M. Heuman; Richard K. Sterling; Mitchell L. Shiffman; Allyne Topaz; Sherry Boyett; Debulon E. Bell; Arun J. Sanyal

Patients with minimal hepatic encephalopathy (MHE) have impaired driving skills, but association of MHE with motor vehicle crashes is unclear. Standard psychometric tests (SPT) or inhibitory control test (ICT) can be used to diagnose MHE. The aim was to determine the association of MHE with crashes and traffic violations over the preceding year and on 1‐year follow‐up. Patients with cirrhosis were diagnosed with MHE by ICT (MHEICT) and SPT (MHESPT). Self and department‐of‐transportation (DOT)‐reports were used to determine crashes and violations over the preceding year. Agreement between self and DOT‐reports was analyzed. Patients then underwent 1‐year follow‐up for crash/violation occurrence. Crashes in those with/without MHEICT and MHESPT were compared. 167 patients with cirrhosis had DOT‐reports, of which 120 also had self‐reports. A significantly higher proportion of MHEICT patients with cirrhosis experienced crashes in the preceding year compared to those without MHE by self‐report (17% vs 0.0%, P = 0.0004) and DOT‐reports (17% vs 3%, P = 0.004, relative risk: 5.77). SPT did not differentiate between those with/without crashes. A significantly higher proportion of patients with crashes had MHEICT compared to MHESPT, both self‐reported (100% vs 50%, P = 0.03) and DOT‐reported (89% vs 44%, P = 0.01). There was excellent agreement between self and DOT‐reports for crashes and violations (Kappa 0.90 and 0.80). 109 patients were followed prospectively. MHEICT patients had a significantly higher future crashes/violations compared to those without (22% vs 7%, P = 0.03) but MHESPT did not. MHEICT (Odds ratio: 4.51) and prior year crash/violation (Odds ratio: 2.96) were significantly associated with future crash/violation occurrence. Conclusion: Patients with cirrhosis and MHEICT have a significantly higher crash rate over the preceding year and on prospective follow‐up compared to patients without MHE. ICT, but not SPT performance is significantly associated with prior and future crashes and violations. There was an excellent agreement between self‐ and DOT‐reports. (HEPATOLOGY 2009.)


PLOS ONE | 2013

Modulation of the Metabiome by Rifaximin in Patients with Cirrhosis and Minimal Hepatic Encephalopathy

Jasmohan S. Bajaj; Douglas M. Heuman; Arun J. Sanyal; Phillip B. Hylemon; Richard K. Sterling; R. Todd Stravitz; Michael Fuchs; Jason M. Ridlon; Kalyani Daita; Pamela Monteith; Nicole A. Noble; Melanie B. White; Andmorgan Fisher; Masoumeh Sikaroodi; Huzefa Rangwala; Patrick M. Gillevet

Hepatic encephalopathy (HE) represents a dysfunctional gut-liver-brain axis in cirrhosis which can negatively impact outcomes. This altered gut-brain relationship has been treated using gut-selective antibiotics such as rifaximin, that improve cognitive function in HE, especially its subclinical form, minimal HE (MHE). However, the precise mechanism of the action of rifaximin in MHE is unclear. We hypothesized that modulation of gut microbiota and their end-products by rifaximin would affect the gut-brain axis and improve cognitive performance in cirrhosis. Aim To perform a systems biology analysis of the microbiome, metabolome and cognitive change after rifaximin in MHE. Methods Twenty cirrhotics with MHE underwent cognitive testing, endotoxin analysis, urine/serum metabolomics (GC and LC-MS) and fecal microbiome assessment (multi-tagged pyrosequencing) at baseline and 8 weeks post-rifaximin 550 mg BID. Changes in cognition, endotoxin, serum/urine metabolites (and microbiome were analyzed using recommended systems biology techniques. Specifically, correlation networks between microbiota and metabolome were analyzed before and after rifaximin. Results There was a significant improvement in cognition(six of seven tests improved,p<0.01) and endotoxemia (0.55 to 0.48 Eu/ml, p = 0.02) after rifaximin. There was a significant increase in serum saturated (myristic, caprylic, palmitic, palmitoleic, oleic and eicosanoic) and unsaturated (linoleic, linolenic, gamma-linolenic and arachnidonic) fatty acids post-rifaximin. No significant microbial change apart from a modest decrease in Veillonellaceae and increase in Eubacteriaceae was observed. Rifaximin resulted in a significant reduction in network connectivity and clustering on the correlation networks. The networks centered on Enterobacteriaceae, Porphyromonadaceae and Bacteroidaceae indicated a shift from pathogenic to beneficial metabolite linkages and better cognition while those centered on autochthonous taxa remained similar. Conclusions Rifaximin is associated with improved cognitive function and endotoxemia in MHE, which is accompanied by alteration of gut bacterial linkages with metabolites without significant change in microbial abundance. Trial Registration ClinicalTrials.gov NCT01069133


The American Journal of Gastroenterology | 2003

Nonalcoholic fatty liver disease in patients with hepatitis C is associated with features of the metabolic syndrome.

Arun J. Sanyal; Melissa J. Contos; Richard K. Sterling; Velimir A. Luketic; Mitchell L. Shiffman; R. Todd Stravitz; A. Scott Mills

OBJECTIVES:The objectives of this study were to determine the following: 1) whether chronic hepatitis C virus (HCV) infection was specifically associated with nonalcoholic fatty liver disease (NAFLD); 2) the factors associated with NAFLD in patients with HCV; and 3) the clinical and histological spectrum of NAFLD occurring together with HCV.METHODS:A retrospective analysis of 3826 biopsies was performed to compare the prevalence of NAFLD in those with HCV versus that in other liver diseases, e.g., hepatitis B, primary biliary cirrhosis, and α1-antitrypsin deficiency. Patients with HCV and NAFLD were also compared with an age- and gender-matched control group with HCV and <5% hepatic steatosis.RESULTS:The prevalence of NAFLD in patients with HCV was similar to that in hepatitis B, primary biliary cirrhosis, or α1-antitrypsin deficiency. The risk of having NAFLD in patients with HCV correlated with body weight (r= 0.7, p < 0.02). Compared with a control group with HCV alone (n = 75), patients with HCV and NAFLD (n = 69) were likely to be heavier (mean BMI 27 vs 30, p < 0.003), diabetic (eight vs 21, p < 0.005), hypertensive (14 vs 25, p < 0.05), and hypertriglyceridemic (15 vs 33, p < 0.05). The HCV viral load, genotype distribution, liver enzymes, liver functions, and ferritin levels were comparable across the study groups. Those with HCV and NAFLD were more likely to have advanced fibrosis (bridging fibrosis or cirrhosis) (26% vs 53%, p < 0.03). Weight, diabetes, and cytological ballooning were independent predictors of advanced fibrosis in those with HCV and NAFLD.CONCLUSION:The presence of NAFLD in patients with HCV is strongly associated with features of the metabolic syndrome and is a risk factor for advanced fibrosis. Advanced fibrosis in such patients is related to weight, presence of diabetes, and presence and degree of cytological ballooning.


Gastroenterology | 2010

Persistence of Cognitive Impairment After Resolution of Overt Hepatic Encephalopathy

Jasmohan S. Bajaj; Christine M. Schubert; Douglas M. Heuman; James B. Wade; Douglas P. Gibson; Allyne Topaz; Kia Saeian; Muhammad Hafeezullah; Debulon E. Bell; Richard K. Sterling; R. Todd Stravitz; Velimir A. Luketic; Melanie B. White; Arun J. Sanyal

BACKGROUND & AIMS In patients with cirrhosis, hepatic encephalopathy (HE) has acute but reversible as well as chronic components. We investigated the extent of residual cognitive impairment following clinical resolution of overt HE (OHE). METHODS Cognitive function of cirrhotic patients was evaluated using psychometric tests (digit symbol, block design, and number connection [NCT-A and B]) and the inhibitory control test (ICT). Improvement (reduction) in ICT lures and first minus second halves (DeltaL(1-2)) were used to determine learning of response inhibition. Two cross-sectional studies (A and B) compared data from stable cirrhotic patients with or without prior OHE. We then prospectively assessed cognitive performance, before and after the first episode of OHE. RESULTS In study A (226 cirrhotic patients), 54 had experienced OHE, 120 had minimal HE, and 52 with no minimal HE. Despite normal mental status on lactulose after OHE, cirrhotic patients were cognitively impaired, based on results from all tests. Learning of response inhibition (DeltaL(1-2) > or =1) was evident in patients with minimal HE and no minimal HE but was lost after OHE. In study B (50 additional patients who developed > or =1 documented OHE episode during follow-up), the number of OHE hospitalizations correlated with severity of residual impairment, indicated by ICT lures (r = 0.5, P = .0001), digit symbol test (r = -0.39, P = .002), and number connection test-B (r = 0.33, P = .04). In the prospective study (59 cirrhotic patients without OHE), 15 developed OHE; ICT lure response worsened significantly after OHE (12 before vs 18 after, P = .0003), and learning of response inhibition was lost. The 44 patients who did not experience OHE did not have deteriorations in cognitive function in serial testing. CONCLUSIONS In cirrhosis, episodes of OHE are associated with persistent and cumulative deficits in working memory, response inhibition, and learning.

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Richard K. Sterling

Virginia Commonwealth University

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Velimir A. Luketic

Virginia Commonwealth University

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Michael Fuchs

Virginia Commonwealth University

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Douglas M. Heuman

Virginia Commonwealth University

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Jasmohan S. Bajaj

Virginia Commonwealth University

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William M. Lee

University of California

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Puneet Puri

Virginia Commonwealth University

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Melanie B. White

Virginia Commonwealth University

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