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Dive into the research topics where Aijaz Ahmed is active.

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Featured researches published by Aijaz Ahmed.


Hepatology | 2014

Nonalcoholic steatohepatitis is the most rapidly growing indication for liver transplantation in patients with hepatocellular carcinoma in the U.S.

Robert J. Wong; Ramsey Cheung; Aijaz Ahmed

Nonalcoholic steatohepatitis (NASH) is currently the third leading indication for liver transplantation (LT) in the U.S. and is predicted to become the leading indication for LT in the near future. The trends in NASH‐related hepatocellular carcinoma (HCC) among LT recipients in the U.S. remain undefined. We performed a retrospective cohort study to evaluate trends in the etiology of HCC among adult LT recipients in the U.S. from 2002 to 2012, using national data from the United Network for Organ Sharing registry. From 2002‐2012, there were 61,868 adults who underwent LT in the U.S., including 10,061 patients with HCC. The total number and proportion of HCC LT recipients demonstrated a significant increase following the implementation of the Model for Endstage Liver Disease (MELD) scoring system in 2002 (3.3%, n = 143 in 2000 versus 12.2%, n = 714 in 2005 versus 23.3%, n = 1336 in 2012). The proportion of hepatitis C virus (HCV)‐related HCC increased steadily from 2002 to 2012, and HCV remained the leading etiology of HCC throughout the MELD era (43.4% in 2002 versus 46.3% in 2007 versus 49.9% in 2012). NASH‐related HCC also increased significantly, and NASH is the second leading etiology of HCC‐related LT (8.3% in 2002 versus 10.3% in 2007 versus 13.5% in 2012). From 2002 to 2012, the number of patients undergoing LT for HCC secondary to NASH increased by nearly 4‐fold, and the number of LT patients with HCC secondary to HCV increased by 2‐fold. Conclusion: NASH is the second leading etiology of HCC leading to LT in the U.S. More important, NASH is currently the most rapidly growing indication for LT in patients with HCC in the U.S. (Hepatology 2014;59:2188–2195)


The Journal of Infectious Diseases | 2009

Ultra-Deep Pyrosequencing of Hepatitis B Virus Quasispecies from Nucleoside and Nucleotide Reverse-Transcriptase Inhibitor (NRTI)–Treated Patients and NRTI-Naive Patients

Severine Margeridon-Thermet; Nancy S. Shulman; Aijaz Ahmed; Rajin Shahriar; Tommy F. Liu; Chunlin Wang; Susan Holmes; Farbod Babrzadeh; Baback Gharizadeh; Bozena Hanczaruk; Birgitte B. Simen; Michael Egholm; Robert W. Shafer

The dynamics of emerging nucleoside and nucleotide reverse-transcriptase inhibitor (NRTI) resistance in hepatitis B virus (HBV) are not well understood because standard dideoxynucleotide direct polymerase chain reaction (PCR) sequencing assays detect drug-resistance mutations only after they have become dominant. To obtain insight into NRTI resistance, we used a new sequencing technology to characterize the spectrum of low-prevalence NRTI-resistance mutations in HBV obtained from 20 plasma samples from 11 NRTI-treated patients and 17 plasma samples from 17 NRTI-naive patients, by using standard direct PCR sequencing and ultra-deep pyrosequencing (UDPS). UDPS detected drug-resistance mutations that were not detected by PCR in 10 samples from 5 NRTI-treated patients, including the lamivudine-resistance mutation V173L (in 5 samples), the entecavir-resistance mutations T184S (in 2 samples) and S202G (in 1 sample), the adefovir-resistance mutation N236T (in 1 sample), and the lamivudine and adefovir-resistance mutations V173L, L180M, A181T, and M204V (in 1 sample). G-to-A hypermutation mediated by the apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like family of cytidine deaminases was estimated to be present in 0.6% of reverse-transcriptase genes. Genotype A coinfection was detected by UDPS in each of 3 patients in whom genotype G virus was detected by direct PCR sequencing. UDPS detected low-prevalence HBV variants with NRTI-resistance mutations, G-to-A hypermutation, and low-level dual genotype infection with a sensitivity not previously possible.


Journal of Clinical Gastroenterology | 2003

The epidemiology of hepatitis C virus infection.

Tommy Yen; Emmet B. Keeffe; Aijaz Ahmed

The prevalence of hepatitis C virus (HCV) infection varies in different populations, ranging from as low as 0.6% in volunteer blood donors to as high as 80% in injection drug users. The prevalence of HCV in a population can be predicted by risk factors associated with the transmission of infection. These risk factors include injection drug use, blood product transfusion, organ transplantation, hemodialysis, occupational injury, sexual transmission, and vertical transmission. We review the literature regarding the incidence and prevalence of HCV infection and the evidence supporting various modes of HCV transmission.


The American Journal of Gastroenterology | 1999

Lamivudine therapy for chemotherapy-induced reactivation of hepatitis B virus infection

Aijaz Ahmed; Emmet B. Keeffe

A 54-yr-old man with lymphoma and serological evidence of prior hepatitis B virus (HBV) infection, with detectable anti-HBc and anti-HBs, was treated with intensive chemotherapy. He had reactivation of HBV infection with acute hepatitis B manifest by detectable HBsAg and elevated aminotransferase levels >1000 IU/L. He was treated with lamivudine 150 mg daily and had prompt resolution of acute hepatitis B with return of elevated aminotransferases to normal, and initial loss of HBeAg with later loss of HBsAg. Lamivudine was continued during the course of further chemotherapy as prophylaxis against repeat HBV reactivation. Lamivudine is a nucleoside analogue that is a potent inhibitor of HBV reverse transcriptase and HBV replication. Lamivudine therapy should be considered for the treatment of HBV reactivation and might play a future role as preemptive therapy of HBV reactivation in patients with prior hepatitis B or chronic hepatitis B with inactive viral replication.


Alimentary Pharmacology & Therapeutics | 2014

The impact of hepatitis C burden: an evidence‐based approach

Zobair M. Younossi; Fasiha Kanwal; Sammy Saab; K. A. Brown; Hashem B. El-Serag; W. R. Kim; Aijaz Ahmed; M. Kugelmas; Stuart C. Gordon

Infection with the hepatitis C virus (HCV) has been considered a major cause of mortality, morbidity and resource utilisation in the US. In addition, HCV is the main cause of hepatocellular cancer (HCC) in the US. Recent developments in the diagnosis and treatment of HCV, including new recommendations pertaining to screening for HCV by the Centers for Disease Control and Prevention and newer treatment regimens with high efficacy, short duration and the potential for interferon‐free therapies, have energised the health care practitioners regarding HCV management.


American Journal of Transplantation | 2009

Transarterial Chemoinfusion for Hepatocellular Carcinoma as Downstaging Therapy and a Bridge toward Liver Transplantation

W. De Luna; Daniel Y. Sze; Aijaz Ahmed; B. Y. Ha; Walid Ayoub; Emmet B. Keeffe; Allen D. Cooper; Carlos O. Esquivel; Mindie H. Nguyen

Favorable outcomes after liver transplantation (LT) in patients with hepatocellular carcinoma (HCC) are well described for patients who fall within defined tumor criteria. The effectiveness of tumor therapies to maintain tumor characteristics within these criteria or to downstage more advanced tumors to fall within these criteria is not well understood. The aim of this study was to examine the response to transcatheter arterial chemoinfusion (TACI) in HCC patients awaiting LT and its efficacy for downstaging or bridging to transplantation. We performed a retrospective study of 248 consecutive TACI cases in 122 HCC patients at a single U.S. medical center. Patients were divided into two groups: those who met the Milan criteria on initial HCC diagnosis (n = 95) and those with more advanced disease (n = 27). With TACI treatment, 87% of the Milan criteria group remained within the Milan criteria and 63% of patients with more advanced disease were successfully downstaged to fall within the Milan criteria. In conclusion, TACI appears to be an effective treatment as a bridge to LT for nearly 90% patients presenting within the Milan criteria and an effective downstaging modality for over half of those whose tumor burden was initially beyond the Milan criteria.


Clinical Gastroenterology and Hepatology | 2015

Nonalcoholic Fatty Liver Disease Review: Diagnosis, Treatment, and Outcomes

Aijaz Ahmed; Robert J. Wong; Stephen A. Harrison

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of abnormal serum aminotransferase levels in both developed and developing countries. Patients with nonalcoholic steatohepatitis (NASH), a subset of NAFLD, are at risk for progressive liver disease and in need of effective treatment options. A practical approach may be pursued by identifying patients with NAFLD with the highest likelihood for histologic evidence of NASH. Despite decades of clinical trials, no single treatment can be recommended to all patients with NASH. Importantly, there is no evidence that pioglitazone or vitamin E improves fibrosis. Bariatric surgeries may improve hepatic histology in morbidly obese patients with NASH, although randomized clinical trials are lacking. Currently, NASH is the second leading etiology of liver disease among adults awaiting liver transplantation in the United States. The primary and secondary prevention of NAFLD may require aggressive strategies for managing obesity, diabetes, and metabolic syndrome.


Alimentary Pharmacology & Therapeutics | 2015

Cost‐effectiveness of all‐oral ledipasvir/sofosbuvir regimens in patients with chronic hepatitis C virus genotype 1 infection

Zobair M. Younossi; Haesuk Park; Sammy Saab; Aijaz Ahmed; Douglas T. Dieterich; Stuart C. Gordon

An all‐oral, pegylated interferon (pegIFN)‐free and ribavirin (RBV)‐free single‐tablet of ledipasvir (LDV) and sofosbuvir (SOF) is now approved for the treatment of patients infected with hepatitis C virus (HCV) genotype 1.


Liver Transplantation | 2004

Older age and liver transplantation: A review

Aijaz Ahmed; Emmet B. Keeffe

Patients older than 60 are undergoing transplantation with increasing frequency. Reports from several transplant centers document that overall short‐term patient survival rates in seniors undergoing liver transplantation are comparable to survival rates of younger adults. However, specific subgroups of older patients may not fare as well. Seniors with far‐advanced end‐stage liver disease are high‐risk for liver transplantation and have poor survival rates. In addition, seniors older than 65 have worse outcomes than those who are 60 to 65, and studies have shown increased mortality with increasing age as a continuous variable. On the other hand, the majority of seniors who survive liver transplantation have full or only minimally limited functional status. Preoperative evaluation of older patients for transplantation requires careful screening to exclude cardiopulmonary disease, malignancy, and other diseases of the aged. Paradoxically, seniors may benefit from a senescent immune system, which results in decreased requirements for immunosuppressive drugs, and possibly a lower rate of acute allograft rejection. Despite good overall short‐term survival in the elderly, long‐term survival may be worse because of an increased rate of long‐term complications, such as malignancy and heart disease. In conclusion, although advanced age is a negative risk factor, advanced age alone should not exclude a patient from liver transplantation; however, it mandates thorough pretransplant evaluation and careful long‐term follow‐up with attention to usual health maintenance issues in the elderly. (Liver Transpl 2004;10:957–967.)


Hepatology | 2014

Randomized, double-blind, controlled study of glycerol phenylbutyrate in hepatic encephalopathy

Don C. Rockey; John M. Vierling; Parvez S. Mantry; Marwan Ghabril; Robert S. Brown; Olga Alexeeva; Igor A. Zupanets; Vladimir Grinevich; Andrey Baranovsky; Larysa Dudar; Galyna Fadieienko; Nataliya Kharchenko; Iryna Klaryts'ka; Vyacheslav Morozov; Priya Grewal; Timothy M. McCashland; K. Gautham Reddy; K. Rajender Reddy; Vasyl Syplyviy; Nathan M. Bass; Klara Dickinson; Catherine Norris; Dion F. Coakley; Masoud Mokhtarani; Bruce F. Scharschmidt; Aijaz Ahmed; Luis A. Balart; B. Berk; Kimberly A. Brown; A. Frolov

Glycerol phenylbutyrate (GPB) lowers ammonia by providing an alternate pathway to urea for waste nitrogen excretion in the form of phenylacetyl glutamine, which is excreted in urine. This randomized, double‐blind, placebo‐controlled phase II trial enrolled 178 patients with cirrhosis, including 59 already taking rifaximin, who had experienced two or more hepatic encephalopathy (HE) events in the previous 6 months. The primary endpoint was the proportion of patients with HE events. Other endpoints included the time to first event, total number of events, HE hospitalizations, symptomatic days, and safety. GPB, at 6 mL orally twice‐daily, significantly reduced the proportion of patients who experienced an HE event (21% versus 36%; P = 0.02), time to first event (hazard ratio [HR] = 0.56; P < 0.05), as well as total events (35 versus 57; P = 0.04), and was associated with fewer HE hospitalizations (13 versus 25; P = 0.06). Among patients not on rifaximin at enrollment, GPB reduced the proportion of patients with an HE event (10% versus 32%; P < 0.01), time to first event (HR = 0.29; P < 0.01), and total events (7 versus 31; P < 0.01). Plasma ammonia was significantly lower in patients on GPB and correlated with HE events when measured either at baseline or during the study. A similar proportion of patients in the GPB (79%) and placebo groups (76%) experienced adverse events. Conclusion: GPB reduced HE events as well as ammonia in patients with cirrhosis and HE and its safety profile was similar to placebo. The findings implicate ammonia in the pathogenesis of HE and suggest that GPB has therapeutic potential in this population. (Clinicaltrials.gov, NCT00999167). (Hepatology 2014;59:1073‐1083)

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Eric R. Yoo

University of Illinois at Chicago

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