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Alcohol-related liver disease (ALD) is the leading indication for liver transplantation (LT) in the USA. Alcohol relapse post-LT can negatively impact long-term outcomes, and prognostic scoring systems are available for further study. Our study aims were to: (1) evaluate the relationship between alcohol relapse and rejection and mortality, (2) investigate risk factors for relapse, and (3) assess predictive validity of the SIPAT (Stanford Integrated Psychosocial Assessment for Transplant) and SALT (Sustained Alcohol Use Post-Liver Transplant) scores on post-LT alcohol relapse. We conducted a retrospective chart review of 155 patients transplanted for chronic ALD at a single transplant center. Cox proportional hazard models assessed the relationship between alcohol relapse and allograft rejection and psychosocial risk factors for relapse. 20% of patients met criteria for alcohol relapse. Alcohol relapse was associated with allograft rejection (HR 2.33, 95% CI 1.11–4.91, p = .03). Three variables most strongly associated with alcohol relapse: prior relapse, failure to engage in recommended alcohol treatment, and continued drinking with liver disease, which were combined into a psychosocial model. SIPAT score≥ 21 and SALT score ≥ 7 were associated with alcohol relapse (HR 6.40, 95% CI 1.36–30.18, p = .019 and HR 2.30, 95% CI 1.12–4.75, p = .024). Receiver operator characteristic analysis compared predictive ability of our psychosocial model to SIPAT (C-statistic .83 compared to .71) and SALT (C-statistic = .77 compared to .62). We identified important psychosocial predictors of post-LT alcohol relapse and validated SIPAT and SALT scores as pre-transplant risk factors for alcohol relapse.

Novel diagnostics have much promise, but they can be difficult to develop from concept to clinical utility. Herein, we review concepts germane to breath research, including metabolite selection and development vision, and offer some practical guidance. Although breath sampling is safe and can inexpensively and quickly deliver measurement results, clinical research evaluating breath analysis must adhere to the same safety and efficacy standards as other forms of clinical trials. A cohesive and well-resourced multidisciplinary team is required. Convincing results are expensive and time consuming to obtain, but essential for clinical, and ultimately, commercial success.

Early liver transplantation for alcoholic hepatitis is a potentially life-saving treatment. As this practice becomes increasingly common, however, the liver transplant community is taking a fresh look at a familiar challenge: best stewardship of donor organs. Herein, we examine a few basic, necessary ethical and practical concerns relevant to this indication.

Ammonia physiology is important to numerous disease states including urea cycle disorders and hepatic encephalopathy. However, many unknowns persist regarding the ammonia response to common and potentially significant physiologic influences, such as food. Our aim was to evaluate the dynamic range of ammonia in response to an oral protein challenge in healthy participants. We measured blood and breath ammonia at baseline and every hour for 5.5 hours. Healthy men (N = 22, aged 18 to 24 years) consumed a 60 g protein shake (high dose); a subset of 10 consumed a 30 g protein shake (moderate dose) and 12 consumed an electrolyte drink containing 0 g protein (control). Change in blood ammonia over time varied by dose (p = 0.001). Difference in blood ammonia was significant for control versus high (p = 0.0004) and moderate versus high (p = 0.03). Change in breath ammonia over time varied by dose (p versus moderate (p = 0.03) and control versus high (p = 0.0003). Changes in blood and breath ammonia were detectable by fast, minimally-invasive (blood) or non-invasive (breath) point-of-care ammonia measurement methods. These pilot data may contribute to understanding normal ammonia metabolism. Novel measurement methods may aid research into genetic and metabolic ammonia disorders.

OBJECTIVE Weight loss through lifestyle changes is recommended for nonalcoholic fatty liver disease (NAFLD). However, its efficacy in patients with type 2 diabetes is unproven. RESEARCH DESIGN AND METHODS Look AHEAD (Action for Health in Diabetes) is a 16-center clinical trial with 5,145 overweight or obese adults with type 2 diabetes, who were randomly assigned to an intensive lifestyle intervention (ILI) to induce a minimum weight loss of 7% or a control group who received diabetes support and education (DSE). In the Fatty Liver Ancillary Study, 96 participants completed proton magnetic resonance spectroscopy to quantify hepatic steatosis and tests to exclude other causes of liver disease at baseline and 12 months. We defined steatosis >5.5% as NAFLD. RESULTS Participants were 49% women and 68% white. The mean age was 61 years, mean BMI was 35 kg/m2, mean steatosis was 8.0%, and mean aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were 20.5 and 24.2 units/l, respectively. After 12 months, participants assigned to ILI (n = 46) lost more weight (−8.5 vs. −0.05%; P < 0.01) than those assigned to DSE and had a greater decline in steatosis (−50.8 vs. −22.8%; P = 0.04) and in A1C (−0.7 vs. −0.2%; P = 0.04). There were no significant 12-month changes in AST or ALT levels. At 12 months, 26% of DSE participants and 3% (1 of 31) of ILI participants without NAFLD at baseline developed NAFLD (P < 0.05). CONCLUSIONS A 12-month intensive lifestyle intervention in patients with type 2 diabetes reduces steatosis and incident NAFLD.

Hepatic magnetic resonance spectroscopy (MRS) is increasingly being applied to many areas of patient-oriented liver research (1). Proton MRS (1H MRS) can quantify triglyceride content in the liver (2) and has become well-established for this purpose (3). Phosphorus MRS (31P MRS) can evaluate complex metabolic processes in vivo and has been applied to many areas of clinical liver research, including investigations of cirrhosis, hepatitis, obstructive jaundice and hepatic energy homoeostasis (4–7). MRS uses standard magnetic resonance equipment, is noninvasive and imparts little risk on study subjects. Further, the data generated by 31P MRS are unique. For example, no other research modality can assess hepatic energy in vivo as indicated by hepatic adenosine triphosphate (ATP) levels. Despite these important attributes, some obstacles are faced by investigators interested in human hepatic MRS. Human hepatic MRS protocols, in particular 31P MRS protocols, can be technically challenging, time consuming and costly. There is considerable variation in data analysis techniques in the published literature, and all share the potential for systematic and random error (8). Perhaps most important, the reported intra- exam and intrasubject variability ranges widely in published studies (9, 10). Furthermore, the effect of fasting or time of day on hepatic ATP levels is uncertain. Accordingly, it is important to understand the technical factors associated with cost-efficient and successful MRS data acquisition and analysis. In this paper, we report our experience with both hepatic 1H and 31P MRS in a cohort of overweight and obese diabetic subjects enrolled in the Action for Health in Diabetes (Look AHEAD) study compared with healthy controls. We also report inter- and intra-observer variability in the evaluation of spectra, and the stability of MRS measurements through repeated examinations on healthy volunteers. We hypothesized that we could successfully complete 1H and 31P MRS in a reliable fashion in obese adults.

To examine five available software packages for the assessment of abdominal adipose tissue with magnetic resonance imaging, compare their features and assess the reliability of measurement results. Feature evaluation and test–retest reliability of softwares (NIHImage, SliceOmatic, Analyze, HippoFat and EasyVision) used in manual, semi-automated or automated segmentation of abdominal adipose tissue. A random sample of 15 obese adults with type 2 diabetes. Axial T1-weighted spin echo images centered at vertebral bodies of L2–L3 were acquired at 1.5 T. Five software packages were evaluated (NIHImage, SliceOmatic, Analyze, HippoFat and EasyVision), comparing manual, semi-automated and automated segmentation approaches. Images were segmented into cross-sectional area (CSA), and the areas of visceral (VAT) and subcutaneous adipose tissue (SAT). Ease of learning and use and the design of the graphical user interface (GUI) were rated. Intra-observer accuracy and agreement between the software packages were calculated using intra-class correlation. Intra-class correlation coefficient was used to obtain test–retest reliability. Three of the five evaluated programs offered a semi-automated technique to segment the images based on histogram values or a user-defined threshold. One software package allowed manual delineation only. One fully automated program demonstrated the drawbacks of uncritical automated processing. The semi-automated approaches reduced variability and measurement error, and improved reproducibility. There was no significant difference in the intra-observer agreement in SAT and CSA. The VAT measurements showed significantly lower test–retest reliability. There were some differences between the software packages in qualitative aspects, such as user friendliness. Four out of five packages provided essentially the same results with respect to the inter- and intra-rater reproducibility. Our results using SliceOmatic, Analyze or NIHImage were comparable and could be used interchangeably. Newly developed fully automated approaches should be compared to one of the examined software packages.

Blood ammonia is routinely used in clinical settings to assess systemic ammonia in hepatic encephalopathy and urea cycle disorders. Despite its drawbacks, blood measurement is often used as a comparator in breath studies because it is a standard clinical test. We sought to evaluate sources of measurement error and potential clinical utility of breath ammonia compared to blood ammonia. We measured breath ammonia in real time by quartz enhanced photoacoustic spectrometry and blood ammonia in 10 healthy and 10 cirrhotic participants. Each participant contributed 5 breath samples and blood for ammonia measurement within 1 h. We calculated the coefficient of variation (CV) for 5 breath ammonia values, reported medians of healthy and cirrhotic participants, and used scatterplots to display breath and blood ammonia. For healthy participants, mean age was 22 years (±4), 70% were men, and body mass index (BMI) was 27 (±5). For cirrhotic participants, mean age was 61 years (±8), 60% were men, and BMI was 31 (±7). Median blood ammonia for healthy participants was within normal range, 10 μmol L(-1) (interquartile range (IQR), 3-18) versus 46 μmol L(-1) (IQR, 23-66) for cirrhotic participants. Median breath ammonia was 379 pmol mL(-1) CO2 (IQR, 265-765) for healthy versus 350 pmol mL(-1) CO2 (IQR, 180-1013) for cirrhotic participants. CV was 17 ± 6%. There remains an important unmet need in the evaluation of systemic ammonia, and breath measurement continues to demonstrate promise to fulfill this need. Given the many differences between breath and blood ammonia measurement, we examined biological explanations for our findings in healthy and cirrhotic participants. We conclude that based upon these preliminary data breath may offer clinically important information this is not provided by blood ammonia.

Quantifying changes in ammonia and ethanol in blood and body fluid assays in response to food is cumbersome. We used breath analysis of ammonia, ethanol, hydrogen (an accepted standard of gut transit) and acetone to investigate gastrointestinal physiology. In 30 healthy participants, we measured each metabolite serially over 6 h in control and high protein trials. Two-way repeated measures ANOVA compared treatment (control versus intervention), change from baseline to maximum and interaction of treatment and time change. Interaction was significant for ammonia (p

Adult-to-adult living donor liver transplantation is an increasingly important option for 17000 patients awaiting liver transplantation in the United States. However, adult-to-adult living donor liver transplantation volumes peaked in 2001 (N=518), and have gradually fallen in 2002 (N=362), 2003 (N=321), and 2004 (N=323). Recent concerns about donor safety and ethical considerations have made careful analysis of donor availability and selection criteria critically important. We conducted a retrospective review of our active liver transplant recipient registry (N=251) and compared it to our living donor registry (N=231), which included all potential living donors before the selection process. Fifteen percent of recipients accounted for the majority (53%) of donor evaluations, whereas 42% of recipients did not have even a single donor evaluation. Recipient diagnosis appears to have a significant impact on donor availability, with donors rarely evaluated for patients with alcoholic cirrhosis. Careful and stringent selection criteria rule out 67% of potential donors.

Scleroderma (systemic sclerosis) is a chronic multisystem autoimmune disease in which oxidative stress is suspected to play a role in the pathophysiology. Therefore, it was postulated that patients with scleroderma would have abnormally high breath ethane concentrations, which is a volatile product of free-radical-mediated lipid peroxidation, compared with a group of controls. There was a significant difference (p0.05) between the mean exhaled ethane concentration of 5.27 pmol ml(-1) CO(2) (SEM=0.76) in the scleroderma patients (n=36) versus the mean exhaled concentration of 2.72 pmol ml(-1) CO(2) (SEM=0.71) in a group of healthy controls (n=21). Within the scleroderma group, those subjects taking a calcium channel blocker had lower ethane concentrations compared with patients who were not taking these drugs (p=0.05). There was a significant inverse association between lung diffusion capacity for carbon monoxide (per cent of predicted) and ethane concentration (b=-2.8, p=0.026, CI=-5.2 to -0.35). These data support the presence of increased oxidative stress among patients with scleroderma that is detected by measuring breath ethane concentrations.

Objectives: Non-alcoholic fatty liver disease (NAFLD) is the most common cause of liver disease in the United States and is prevalent in morbidly obese patients. While weight loss and treatment of risk factors are recommended, the reported effects of bariatric surgery on NAFLD are mixed. Research Methods and Procedures: We examined liver histology at the time of Roux-en-Y gastric bypass surgery and at elective incisional hernia repair after weight loss for 16 patients at one center. Slides were read by one pathologist, blinded to clinical data, using the Brunt criteria. Clinical and laboratory data were extracted from chart review. Alcohol use was ascertained by two interviews. Results: At baseline, the mean age was 44 years, 50% were women, 88% were white, and the mean BMI was 51 kg/m2. None had significant alcohol use. On initial biopsy, all patients showed steatosis, 94% had inflammation, 88% had ballooning degeneration, 88% had perisinusoidal fibrosis, and 81% had portal fibrosis. The mean time between the two biopsies was 305 ± 131 (SD) days. The mean weight loss was 118 ± 29 lb. Steatosis improved in 15 of 16 patients, with resolution in 13. Twelve of 15 patients with inflammation at baseline showed improvement, and 12 of 14 showed less ballooning. Six of 14 patients with perisinusoidal fibrosis and 6 of 13 with portal fibrosis showed improvement. No patient had worsening of steatosis, inflammation, ballooning, or fibrosis. Discussion: Our study shows improvement in all of the histological features of NAFLD after Roux-en-Y gastric bypass surgery—induced weight loss, despite significant histopathology at baseline and substantial weight loss.

Hepatic phosphorus magnetic resonance spectroscopy (31P MRS) offers the exciting potential of studying metabolic processes in the human liver in vivo. Many investigators have utilized 31P MRS to research a broad range of metabolic questions, and there is outstanding potential for this imaging modality in the future. However, at times it is difficult to appreciate this potential because most published series have been small, and comparisons between studies are difficult. Indeed, the published literature contains significant variation in data acquisition and data analysis techniques and, perhaps most importantly, the interpretation of the data itself. As MR technology continues to evolve and more studies are being performed, perhaps a greater consensus of study techniques and endpoints will emerge. This review summarizes the present literature on human hepatic 31P MRS.

Nonalcoholic fatty liver disease (NAFLD) is a common and potentially serious form of chronic liver disease that occurs in patients who do not abuse alcohol. Present dietary recommendations for all Americans, including those with NAFLD, endorse a low-calorie, low-fat diet. However, little is known about the effect of diet composition on liver histopathology in patients with NAFLD. The aim of this study was to determine whether overall calorie intake and diet composition are associated with the severity of NAFLD histopathology. Seventy-four consecutive morbidly obese patients presenting for bariatric surgery from January 2001 to March 2002 were retrospectively reviewed. In addition to a standard surgical and psychological evaluation, all patients underwent a preoperative dietary evaluation using a standardized 24-hr food recall. Food intake was evaluated for total calories and macronutrients and compared to liver histopathology from biopsies routinely obtained during surgery. Associations with the severity of steatosis and the presence of inflammation or fibrosis were assessed separately using chi-square for categorical variables and ANOVA for continuous variables. Further, we conducted multiple logistic regression analyses for each histological outcome. There were no significant associations between either total caloric intake or protein intake and either steatosis, fibrosis, or inflammation. However, higher CHO intake was associated with significantly higher odds of inflammation, while higher fat intake was associated with significantly lower odds of inflammation. In conclusion, present dietary recommendations may worsen NAFLD histopathology.

Tremendous progress has been made over the past decade in the understanding of the pathogenesis of non-alcoholic fatty liver disease (NAFLD) and its associated disease burden. Much of this research has re-focused attention on the relationship between intestinal bacteria and liver disease. The concept that gut-derived bacteria and their products injure the liver and cause systemic illness has surfaced and resurged repeatedly. Indeed, one review of this topic written just over a decade ago (subtitled An Idea Whose Time Has Come Again) argued

We report a case of intravenous (IV) amiodarone drug induced liver injury (DILI). The patient received IV N-acetylcysteine (NAC) which resulted in a rapid improvement in liver enzymes. While the specific mechanisms for the pathogenesis of IV amiodarone DILI and the therapeutic action of IV NAC are both unknown, this case strongly implies at least some commonality. Because IV amiodarone is indicated for the treatment of serious cardiac arrhythmias in an intensive care unit setting, some degree of ischemic hepatitis is likely a cofactor in most cases.

This exhaled breath ammonia method uses a fast and highly sensitive spectroscopic method known as quartz enhanced photoacoustic spectroscopy (QEPAS) that uses a quantum cascade based laser. The monitor is coupled to a sampler that measures mouth pressure and carbon dioxide. The system is temperature controlled and specifically designed to address the reactivity of this compound. The sampler provides immediate feedback to the subject and the technician on the quality of the breath effort. Together with the quick response time of the monitor, this system is capable of accurately measuring exhaled breath ammonia representative of deep lung systemic levels. Because the system is easy to use and produces real time results, it has enabled experiments to identify factors that influence measurements. For example, mouth rinse and oral pH reproducibly and significantly affect results and therefore must be controlled. Temperature and mode of breathing are other examples. As our understanding of these factors evolves, error is reduced, and clinical studies become more meaningful. This system is very reliable and individual measurements are inexpensive. The sampler is relatively inexpensive and quite portable, but the monitor is neither. This limits options for some clinical studies and provides rational for future innovations.

Provides an overview of the technical articles and features presented in this issue on swarming in natural and engineered systems.

Amongst volatile compounds (VCs) present in exhaled breath, ammonia has held great promise and yet it has confounded researchers due to its inherent reactivity. Herein we have evaluated various factors in both breath instrumentation and the breath collection process in an effort to reduce variability. We found that the temperature of breath sampler and breath sensor, mouth rinse pH, and mode of breathing to be important factors. The influence of the rinses is heavily dependent upon the pH of the rinse. The basic rinse (pH 8.0) caused a mean increase of the ammonia concentration by 410 ± 221 ppb. The neutral rinse (pH 7.0), slightly acidic rinse (pH 5.8), and acidic rinse (pH 2.5) caused a mean decrease of the ammonia concentration by 498 ± 355 ppb, 527 ± 198 ppb, and 596 ± 385 ppb, respectively. Mode of breathing (mouth-open versus mouth-closed) demonstrated itself to have a large impact on the rate of recovery of breath ammonia after a water rinse. Within 30 min, breath ammonia returned to 98 ± 16% that of the baseline with mouth open breathing, while mouth closed breathing allowed breath ammonia to return to 53 ± 14% of baseline. These results contribute to a growing body of literature that will improve reproducibly in ammonia and other VCs. (Some figures may appear in colour only in the online journal)

Quantum cascade laser based breath sensor platform for medical applications employing a quartz-enhanced photoacoustic spectroscopy technique is reported. The detection sensitivity for exhaled ammonia is at ≪10 ppbv level with 1 s time resolution.

The accurate diagnosis and staging of hepatic fibrosis is crucial for prognosis and treatment of liver disease. The current gold standard, liver biopsy, cannot be used for population-based screening, and has well known drawbacks if used for monitoring of disease progression or treatment success. Our objective was to assess performance and promise of radiologic modalities and techniques as alternative, noninvasive assessment of hepatic fibrosis. A systematic review was conducted. Six hundred twenty-eight studies were identified via electronic search. One hundred fifty-three papers were reviewed. Most described techniques that could differentiate between cirrhosis or severe fibrosis and normal liver. Accurate staging of fibrosis or diagnosis of mild fibrosis was often not achievable. Ultrasonography is the most common modality used in the diagnosis and staging of hepatic fibrosis. Elastographic measurements, either ultrasonography-based or magnetic resonance-based, and magnetic resonance diffusion weighted imaging, show the most promise for accurate staging of hepatic fibrosis. Most currently available imaging techniques can detect cirrhosis or significant fibrosis reasonably accurately. However, to date only magnetic resonance elastography has been able to stage fibrosis or diagnose mild disease. Utrasonographic elastography and magnetic resonance diffusion weighted appear next most promising.

Breath biomarkers have the potential to offer information that is similar to conventional clinical tests or they are entirely unique. Preliminary data support the use of breath biomarkers in the study of liver disease, in particular non-alcoholic fatty liver disease (NAFLD). It was evaluated whether breath ethanol, ethane, sulfur compounds and acetone would be associated with hepatic histopathology amongst morbidly obese patients presenting for bariatric surgery. Breath samples were collected during a preoperative visit and compared with liver biopsies obtained during the surgery. A Student's two-tailed t-test was used to compare differences between the two groups. Linear regression was used to analyse associations between the concentrations of breath molecules and independent predictor variables. It was found that breath ethanol, ethane and acetone can be useful biomarkers in patients with NAFLD. In particular, breath ethanol can be associated with hepatic steatosis, and breath acetone can be associated with non-alcoholic steatohepatitis.

Purpose Nonalcoholic fatty liver disease (NAFLD) is a common and potentially serious form of chronic liver disease. Although NAFLD is known to be associated with obesity and some comorbid conditions, less is known about the severity of NAFLD among different racial groups. Methods We prospectively studied 237 consecutive morbidly obese patients presenting for bariatric surgery. All patients underwent intraoperative liver biopsy and chart review. After excluding subjects who reported alcohol use (n = 37) or who had missing biopsy data (n = 11), 189 patients were available for analysis. Clinical and laboratory associations with each of the histological components of NAFLD were assessed using multiple logistic regression analysis. Results The mean age was 43.1 years, 84% were female, and 13% were African American. It was found that 88% had steatosis, including 35% with moderate to severe steatosis (> 33% of hepatocytes involved). Of these patients, 67% had inflammation, 46% had fibrosis, and 45% met Brunt's criteria for NASH. Compared with Caucasians and after adjustment, African Americans had significantly lower odds of severe hepatic pathology, with adjusted odds ratios of 0.1 ( P = .02) for the presence of moderate or severe steatosis, 0.2 for inflammation ( P = .006), 0.3 for fibrosis ( P = .05), and 0.2 for NASH ( P = .02). In addition, participants with one or more features of the metabolic syndrome (ie, diabetes, hypertension, or dyslipidemia) or elevated aminotransferase levels had significantly higher odds of severe hepatic histopathology. Conclusion Among obese patients presenting for bariatric surgery, NAFLD is more common in Caucasians, patients with features of the metabolic syndrome, and those with elevated aminotransferase levels.

Hepatic encephalopathy (HE) is a common and dreaded complication of liver disease. The effects of HE can range from minimal to life threatening. Even 'minimal HE' causes major dysfunction in many aspects of daily living. The exact pathogenesis of HE remains unknown. However, the products of gut flora metabolism are universally recognized as critical. Present treatments for HE include the cathartic agent lactulose and poorly absorbable antibiotics. While effective, these treatments incur numerous side-effects and cost. Probiotics are viable bacteria given orally to improve health. Probiotics have multiple mechanisms of action that could disrupt the pathogenesis of HE and may make them superior to conventional treatment.

Breath ammonia has proven to be a difficult compound to measure accurately. The goal of this study was to evaluate the effects that the physiological intervention, exercise, had on the levels of breath ammonia. The effects of vigorous exercise (4000 m indoor row) in 13 participants were studied and increases in breath ammonia were observed in all participants. Mean pre-exercise concentrations of ammonia were 670 pmol ml(-1) CO2 (SD, 446) and these concentrations increased to post-exercise maxima of 1499 pmol ml(-1) CO2 (SD, 730), p 0.0001. The mean increase in ammonia concentrations from pre-exercise to maximum achieved in conditioned (1362 pmol ml(-1) CO2) versus non-conditioned rowers (591 pmol ml(-1) CO2) were found to be statistically different, p = 0.029. Taken together, these results demonstrate our ability to repeatedly measure the influence of exercise on the concentration of breath ammonia.