Nonalcoholic steatohepatitis (NASH) is often linked with disorders that are clearly associated with insulin resistance (IR): obesity, type 2 diabetes mellitus, and hypertriglyceridemia. We tested the hypotheses that (1) IR is an essential requirement for the development of NASH and (2) a high association between IR and liver disease is relatively specific for NASH. We measured body mass index (BMI), waist/hip ratio, and fasting serum lipid, insulin, C-peptide, and glucose levels in 66 patients with NASH (21 with advanced fibrosis and 45 with mild fibrosis). IR was determined by the homeostasis model assessment (HOMA). We also determined the strength of the association of NASH with insulin resistance syndrome (IRS) as defined by World Health Organization criteria. To assess whether the finding of IR was relatively specific to NASH rather than simply to obesity or liver disease, we compared the results of a subset of 36 patients with less-severe NASH with 36 age-and sex-matched patients with chronic hepatitis C virus (HCV) of comparable fibrotic severity. IR was confirmed in 65 patients (98%) with NASH, and 55 (87%) fulfilled minimum criteria for IRS. IR was found in lean as well as in overweight and obese patients. The IR values and the prevalence of IRS (75% vs. 8.3%) were significantly higher in those with NASH than in comparable cases of HCV. Hyperinsulinemia was attributable to increased insulin secretion rather than decreased hepatic extraction. N onalcoholic steatohepatitis (NASH) is characterized by morphological features indistinguishable from alcoholic liver disease in individuals who do not consume excess alcohol. 1 NASH can progress to cirrhosis, and death from liver failure is now the second-leading cause of death in these patients. 2 Although the prevalence of NASH appears to be increasing, the etiopathogenesis remains poorly understood.Associations with drug toxicity, weight-reducing operations, lipodystrophy, and other uncommon inherited syndromes are well documented but are rarely present in most patients with NASH. [1][2][3][4][5][6][7][8] Rather, attention has been drawn to the increased prevalence of common metabolic disorders in the "typical" patient with NASH. [1][2][3][4][5][6][7] Autopsy data indicate that NASH is at least 6 times more prevalent in obese individuals compared with lean subjects. 7 Type 2 diabetes mellitus or abnormalities of glucose tolerance are present in up to one third of patients with NASH, 8 often with hypertriglyceridemia and/or hypercholesterolemia. 9,10 The above metabolic disorders are also cardiovascular risk factors and often cluster together as syndrome X, which includes impaired glucose tolerance, dyslipidemia, and hypertension. 11 This disease cluster is also referred to as the metabolic or insulin resistance syndrome (IRS); the latter highlights a central role for insulin resistance (IR) in this disorder. 12,13 The expanded formulation of IRS includes central (visceral or truncal) adiposity, lipid abnormalities, hyperuricemia, polycystic ovarian syndrome, and...

Background Three clusters of coronavirus disease 2019 (COVID-19) linked to a tour group from China, a company conference, and a church were identified in Singapore in February, 2020.Methods We gathered epidemiological and clinical data from individuals with confirmed COVID-19, via interviews and inpatient medical records, and we did field investigations to assess interactions and possible modes of transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Open source reports were obtained for overseas cases. We reported the median (IQR) incubation period of SARS-CoV-2. Findings As of Feb 15, 2020, 36 cases of COVID-19 were linked epidemiologically to the first three clusters of circumscribed local transmission in Singapore. 425 close contacts were quarantined. Direct or prolonged close contact was reported among affected individuals, although indirect transmission (eg, via fomites and shared food) could not be excluded. The median incubation period of SARS-CoV-2 was 4 days (IQR 3-6). The serial interval between transmission pairs ranged between 3 days and 8 days.Interpretation SARS-CoV-2 is transmissible in community settings, and local clusters of COVID-19 are expected in countries with high travel volume from China before the lockdown of Wuhan and institution of travel restrictions. Enhanced surveillance and contact tracing is essential to minimise the risk of widespread transmission in the community.Funding None. Articles 2www.thelancet.com Published online March 16, 2020 https://doi.

Nonalcoholic steatohepatitis (NASH) is a disorder characterized by hepatic steatosis, inflammation, and fibrosis. Leptin is an adipocyte-derived antiobesity hormone that in rodents prevents "lipotoxicity" by limiting triglyceride accumulation and also regulates matrix deposition (fibrosis) during wound healing. We therefore determined serum leptin levels in patients with NASH to determine whether relationships existed between leptin levels and severity of hepatic steatosis or fibrosis. We used a radioimmunoassay to determine serum [total] leptin concentrations in 27 men and 20 women with NASH and 47 controls matched for gender and body mass index (BMI; and partly for age). Serum leptin values were correlated with hepatic steatosis, fibrosis, and inflammation (each categorized semiquantitatively on liver histology), and with anthropometric indices, serum lipids, glucose, insulin, c-peptide, and alanine aminotransferase (ALT) levels. Compared with the controls, mean serum leptin levels were raised in both men and women with NASH (men 14 ؎ 11 ng/mL vs. 7.2 ؎ 4.1 ng/mL, P ‫؍‬ .003; women 35 ؎ 16 ng/mL vs. 15 ؎ 8.2 ng/mL, P < .001). Leptin values correlated with serum c-peptide levels but not with BMI. In a multivariate analysis, serum leptin (P ‫؍‬ .027), serum c-peptide (P ‫؍‬ .001), and age (P ‫؍‬ .027) were selected as independent predictors of the severity of hepatic steatosis. However, serum leptin was not an independent predictor of hepatic inflammation or fibrotic severity. In conclusion, hyperleptinemia occurs in NASH and is not explained simply by gender, obesity, or the presence of type 2 diabetes. Furthermore, leptin levels correlate directly with the severity of hepatic steatosis but not with inflammation or fibrosis. We propose that the relationship between leptin and steatosis reflects a pathogenic role of leptin in hepatic insulin resistance and/or a failure of the antisteatotic actions of leptin ("peripheral leptin resistance"). (HEPATOLOGY 2002;36:403-409.) L eptin is the 16-kd peptide product of the ob gene. It was initially characterized as a regulator of body weight and energy expenditure. 1 It seems unlikely that the principal function of leptin would be to limit obesity, because starvation and famine rather than food excess have typified much of human evolution. 2 From animal studies, it is now emerging that one of the main physiological roles of leptin is to prevent lipid accumulation in nonadipose sites, such as the myocardium, skeletal muscle, pancreas, and liver, 3,4 a concept referred to as "lipotoxicity."Although lipotoxicity is not currently defined as a distinct entity in humans, it has been demonstrated in several experimental models. 3,4 Thus, whereas rodents fed a highfat diet (60% of energy content) develop steatosis, 3 lipid accumulation in the liver (1-to 2.7-fold increase) is disproportionately less than the increase in body fat (ϳ150-fold). By contrast, leptin-deficient (ob/ob) mice and leptin-unresponsive (db/db, fa/fa) rats that received only a 6% fat diet developed extre...