Occult liver disease burden: Analysis from a large general practitioners' database

Occult liver disease: A multinational perspective

Occult liver disease refers to the presence of unrecognized chronic liver disease and cirrhosis. Liver disease is currently the eleventh cause of death globally, representing 4% of all deaths in the world. Alcohol consumption is the leading cause of cirrhosis globally, accounting for approximately 60% of cases. The estimated global prevalence of non-alcoholic fatty liver disease (NAFLD) is 32.4% and has been steadily increasing over the last years. Viral hepatitis B and C accounted for 1.3 million deaths in 2020. Several studies in populations at high risk of chronic liver disease (elevated liver enzymes, type 2 diabetes, excessive alcohol consumption) have found an elevated prevalence of occult liver disease. Attempts should be made to assess the prevalence of occult liver disease in Latin America, a region with one of the highest rates of metabolic diseases and excessive alcohol consumption. Screening for NAFLD in high-risk subjects and screening for excessive drinking and alcohol use disorders at every level of medical care is relevant. Efforts should also focus on the early treatment of occult liver disease to try to reduce liver disease burden and, in the case of occult viral hepatitis infection, prevent further spreading.

Electronic sanitary database: a new potential tool to identify occult chronic liver disease in general population

Chronic liver disease (CLD) is a leading global cause of mortality, morbidity, and healthcare resource utilization. However, the burden of CLD is underestimated because the course of the disease is often asymptomatic until clinical decompensation and the development of life-threatening complications. In this study, we assessed the use of available blood tests from electronic medical records for identifying individuals with undiagnosed CLD in the general population. We analyzed a total of 202,529 blood tests obtained from 99,848 adults recorded in the Electronic Health Records of the Padova Teaching Hospital. Transaminases levels > 1.5 times the normal value indicated occult CLD, while platelet counts < 120,000/μL identified occult cirrhosis. We characterized patients using Italian Medical Exemptions (IME), excluding oncologic cases. Overt and occult cirrhosis prevalence was 1% and 4.18%, respectively, while overt and occult CLD affected 2.85% and 4.61% of the population. The epidemiology of patients with overt and occult cirrhosis was similar but significantly different from that of the controls. Among subjects aged 60-70 years, working disability was twofold higher in those with occult cirrhosis compared to those with overt cirrhosis. Occult CLD and cirrhosis had higher prevalence rates than diagnosed cases in the general population. Electronic medical record data may serve as a valuable tool for CLD identification, potentially reducing cirrhosis development and clinical decompensation. This, in turn, may lead to a decrease in the economic impact on the healthcare system.

Kupffer cell-like syncytia replenish resident macrophage function in the fibrotic liver

Kupffer cells (KCs) are localized in liver sinusoids but extend pseudopods to parenchymal cells to maintain their identity and serve as the body's central bacterial filter. Liver cirrhosis drastically alters vascular architecture, but how KCs adapt is unclear. We used a mouse model of liver fibrosis and human tissue to examine immune adaptation. Fibrosis forced KCs to lose contact with parenchymal cells, down-regulating "KC identity," which rendered them incapable of clearing bacteria. Commensals stimulated the recruitment of monocytes through CD44 to a spatially distinct vascular compartment. There, recruited monocytes formed large aggregates of multinucleated cells (syncytia) that expressed phenotypical KC markers and displayed enhanced bacterial capture ability. Syncytia formed via CD36 and were observed in human cirrhosis as a possible antimicrobial defense that evolved with fibrosis.

Undiagnosed abnormal alanine transaminase levels in vulnerable populations: Impact of sex, race/ethnicity, and body mass

Background

Liver disease is a leading cause of death in the United States and is often initially detected incidentally on lab tests ordered by general practitioners. Alanine transaminase (ALT), a marker of liver inflammation, is commonly ordered and may be abnormal in the setting of elevated body mass index, diabetes and dyslipidemia. Data regarding ALT testing within vulnerable populations are limited. Therefore, the prevalence of ALT testing and abnormal ALT in the absence of known chronic liver disease (CLD) among a safety-net population were assessed and factors associated with these outcomes were identified.

Methods

In this retrospective longitudinal study of 92,997 patients seen between 01/2017-01/2019 within San Francisco's Safety-Net Healthcare System, electronic medical records were used to abstract data back to 04/1997. Descriptive analyses and multivariable modeling were performed.

Results

Overall, 59,323 (69%) without known CLD received an ALT test. Age, Black race, Latinx ethnicity, and metabolic factors were associated with higher odds of ALT testing, (p < 0.01). Among those with an abnormal ALT (44%) without known CLD: median age 53 years, 41% male, 19% White, 11% Black, 40% Latinx, 29% Asian/Pacific Islander (API), and 84% overweight/obese. On multivariable analysis, female sex (OR 2.7), Latinx ethnicity (OR 2.6), API race (OR 1.3), overweight/obesity (OR 1.8, OR 2.6), and dyslipidemia (OR 1.3) were associated with abnormal ALT, (p ≤ 0.001).

Conclusions

In the absence of known CLD, women, Latinx, API and persons with excess body weight were associated with greater odds of abnormal ALT. Future longitudinal studies are needed to confirm these differences and to determine if adequate work up for CLD is performed for abnormal ALT levels among at-risk populations.

Metformin-Associated Lactic Acidosis in a Diabetic Patient with Normal Kidney Function and Occult Cirrhosis

Background

Lactic acidosis is a well-known complication of metformin accumulation in diabetic patients with kidney failure. However, it is not usual to raise the diagnosis of metformin-associated lactic acidosis when patients have normal kidney function. The causes of metformin-induced high lactate include the accumulation of normal doses of metformin in chronic kidney disease, an overdose of this drug without kidney failure, or an increase in lactate production due to the inhibition of liver gluconeogenesis. Case Presentation. We report the case of a 61-year-old diabetic man who was brought to the emergency room in a comatose state. His family reported abdominal pain with diarrhea in the last two days. He was found to have severe lactic acidosis with normal serum creatinine. He was on a regular dose of metformin, and his family denied any other medical history or any alcohol abuse. He showed no signs of infection, his liver enzymes were slightly elevated, and he had severe anemia. His hemodynamics deteriorated quickly within hours, and an abdominal computed tomography scan revealed no abnormalities. He underwent a laparotomy that ruled out mesenteric ischemia and revealed an abnormal liver. The liver biopsy later confirmed the diagnosis of cirrhosis.

Conclusions

We discuss here the probable causes of severe lactic acidosis and the role of metformin in exacerbating this acid-base disturbance in cirrhotic patients. Future research is needed to determine whether these patients might benefit from dialysis.

MELD-Na Score as a Predictor of Postoperative Complications in Ventral Skull Base Surgery

Background: The Model for End-stage Liver Disease-Sodium (MELD-Na) Score was designed for prognosis of chronic liver disease and has been predictive of outcomes in a variety of procedures. Few studies have investigated its utility in Otolaryngology. This study uses the MELD-Na score to investigate the association between liver health and ventral skull base surgical complications. Methods: The National Surgical Quality Improvement Program database was used to identify patients who underwent ventral skull base procedures between 2005 and 2015. Univariate and multivariate analyses were performed to investigate the association between elevated MELD-Na score and postoperative complications. Results: 1077 patients undergoing ventral skull base surgery with lab values required to calculate the MELD-Na score were identified. The mean age was 54.2 years. The mean MELD-Na score was 7.70 (SD=2.04). Univariate analysis showed that elevated MELD-Na score was significantly associated with increased age (58.6 vs. 53.8 years) and male gender (70.8% vs. 46.1%). Elevated MELD-Na score was associated with increased rates of postoperative acute renal failure, transfusion, septic shock, surgical complications, and extended length of hospital stay. On multivariate analysis, associations between elevated MELD-Na and increased risk of perioperative transfusions (OR 1.62, 95%CI 1.20-2.93, p=0.007) and surgical complications (OR 1.58, 95%CI 1.25-2.35, p=0.009) remained significant. Conclusions: This analysis points to an association between liver health and postoperative complications in ventral skull base surgery. Future research investigating this association is warranted.

Scaffolding Protein IQGAP1 Is Dispensable, but Its Overexpression Promotes Hepatocellular Carcinoma via YAP1 Signaling

IQ motif-containing GTPase-activating protein 1 (IQGAP1) is a ubiquitously expressed scaffolding protein that is overexpressed in a number of cancers, including liver cancer, and is associated with protumorigenic processes, such as cell proliferation, motility, and adhesion. IQGAP1 can integrate multiple signaling pathways and could be an effective antitumor target. Therefore, we examined the role of IQGAP1 in tumor initiation and promotion during liver carcinogenesis. We found that ectopic overexpression of IQGAP1 in the liver is not sufficient to initiate tumorigenesis. Moreover, we report that the tumor burden and cell proliferation in the diethylnitrosamine-induced liver carcinogenesis model in Iqgap1-/- mice may be driven by MET signaling. In contrast, IQGAP1 overexpression enhanced YAP activation and subsequent NUAK2 expression to accelerate and promote hepatocellular carcinoma (HCC) in a clinically relevant model expressing activated (S45Y) β-catenin and MET. Here, increasing IQGAP1 expression in vivo does not alter β-catenin or MET activation; instead, it promotes YAP activity. Overall, we demonstrate that although IQGAP1 expression is not required for HCC development, the gain of IQGAP1 function promotes the rapid onset and increased liver carcinogenesis. Our results show that an adequate amount of IQGAP1 scaffold is necessary to maintain the quiescent status of the liver.

Burden of nonalcoholic fatty liver disease in Canada, 2019-2030: a modelling study

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) account for a growing proportion of liver disease cases, and there is a need to better understand future disease burden. We used a modelling framework to forecast the burden of disease of NAFLD and NASH for Canada.

METHODS

We used a Markov model to forecast fibrosis progression from stage F0 (no fibrosis) to stage F4 (compensated cirrhosis) and subsequent progression to decompensated cirrhosis, hepatocellular carcinoma, liver transplantation and liver-related death among Canadians with NAFLD from 2019 to 2030. We used historical trends for obesity prevalence among adults to estimate longitudinal changes in the number of incident NAFLD cases.

RESULTS

The model projected that the number of NAFLD cases would increase by 20% between 2019 and 2030, from an estimated 7 757 000 cases to 9 305 000 cases. Increases in advanced fibrosis cases were relatively greater, as the number of model-estimated prevalent stage F3 cases would increase by 65%, to 357 000, and that of prevalent stage F4 cases would increase by 95%, to 195 000. Estimated incident cases of hepatocellular carcinoma and decompensated cirrhosis would increase by up to 95%, and the number of annual NAFLD-related deaths would double, to 5600.

INTERPRETATION

Increasing rates of obesity translate into increasing NAFLD-related cases of cirrhosis and hepatocellular carcinoma and related mortality. Prevention efforts should be aimed at reducing the incidence of NAFLD and slowing fibrosis progression among those already affected.

A practical clinical approach to liver fibrosis

Liver fibrosis is a slow, insidious process involving accumulation of extracellular matrix protein in the liver. The stage of liver fibrosis in chronic liver disease (CLD) determines overall morbidity and mortality; the higher the stage, the worse the prognosis. Noninvasive composite scores can be used to determine whether patients with CLD have significant or advanced fibrosis. Patients with low composite scores can be safely followed up in primary care with periodic reassessment. Those with higher scores should be referred to a specialist. As the epidemic of diabetes mellitus, obesity and non-alcoholic fatty liver diseases is rising, CLD is becoming more prevalent. Easy-to-use fibrosis assessment composite scores can identify patients with minimal or advanced fibrosis, and should be an integral part of decision-making. Patients with cirrhosis, high composite scores, chronic hepatitis B with elevated alanine aminotransferase and aspartate aminotransferase, or deranged liver panel of uncertain aetiology should be referred to a specialist.

Effects of Underlying Liver Disease on 30-Day Outcomes After Posterior Lumbar Fusion

OBJECTIVE

To examine the effects of underlying liver disease on 30-day postoperative complications after elective posterior lumbar fusion (PLF).

METHODS

We performed a retrospective American College of Surgeons National Surgical Quality Improvement Program study of patients who had undergone elective PLF from 2011 to 2014. The patients were divided into 2 groups stratified by the presence of liver disease, assessed using the Model for End-stage Liver Disease plus sodium score (liver disease, ≥10; no liver disease, <10). The baseline patient and operative characteristics were compared between the 2 groups using univariate analysis. Subsequent multivariate regression analysis adjusted for differences in baseline characteristics was performed to identify 30-day postoperative complications independently associated with liver disease.

RESULTS

Of 2965 patients, 55.9% had underlying liver disease. Those with liver disease were more frequently aged >65 years, male, and underweight or overweight and had had American Society of Anesthesiologists class ≥3, diabetes, pulmonary comorbidity, cardiac comorbidity, renal comorbidity, bleeding disorder, preoperative dyspnea at rest, and a prolonged operative time. On univariate analysis, patients with liver disease had a greater incidence of cardiac complications, pulmonary complications, renal complications, blood transfusion, sepsis, urinary tract infection, and prolonged hospitalization. On adjusted multivariate regression analysis, liver disease was independently associated with renal complications, pulmonary complications, sepsis, urinary tract infection, prolonged hospitalization, and blood transfusion.

CONCLUSIONS

As the long-term survival of patients with liver disease continues to increase, a better understanding of the relationship between liver dysfunction and surgical outcomes is needed. The identification of modifiable risk factors would allow them to be addressed and optimized preoperatively to decrease the incidence and severity of complications and improve patient outcomes after PLF.