The incidence of gallstone disease has increased in recent years. The pathogenesis of cholelithiasis is not fully understood. The occurrence of the disease is influenced by both genetic and environmental factors. This article reviews the literature on cholelithiasis in children, with the exception of articles on hematological causes of cholelithiasis and cholelithiasis surgery. The aim of this review is to present the latest research on the pathogenesis of gallstone disease in children. The paper discusses the influence of all factors known so far, such as genetic predisposition, age, infections, medications used, parenteral nutrition, and comorbidities, on the development of gallstone disease. The course of cholelithiasis in the pediatric population is complex, ranging from asymptomatic to life-threatening. Understanding the course of the disease and predisposing factors can result in a faster diagnosis of the disease and administration of appropriate treatment.

There is a need to replace liver biopsy with non-invasive markers that predict the degree of liver fibrosis in fatty liver disease related to obesity. Therefore, we studied four potential serum markers of liver fibrosis and compared them with histopathological findings in liver biopsy in children with non-alcoholic fatty liver disease (NAFLD). We determined fasting serum level of hyaluronic acid (HA), laminin, YKL-40 and cytokeratin-18 M30 in 52 children (age range 4-19, mean 12 years, 80 % of them were overweight or obese) with biopsy-verified NAFLD. Viral hepatitis, autoimmune and metabolic liver diseases (Wilson's disease, alpha-1-antitrypsin deficiency, cystic fibrosis) were excluded. Fibrosis stage was assessed in a blinded fashion by one pathologist according to Kleiner. Receiver operating characteristics (ROC) analysis was used to calculate the power of the assays to detect liver fibrosis (AccuROC, Canada). Liver fibrosis was diagnosed in 19 children (37 %). The levels of HA and CK18M30 were significantly higher in children with fibrosis compared to children without fibrosis (p=0.04 and 0.05 respectively). The ability of serum HA (cut-off 19.1 ng/ml, Se=84 %, Sp=55 %, PPV=52 %, NPV=86 %) and CK18M30 (cut-off 210 u/l, Se=79 %, Sp=60 %, PPV=56 %, NPV=82 %) to differentiate children with fibrosis from those without fibrosis was significant (AUC=0.672 and 0.666, respectively). The combination of both markers was superior (AUC=0.73, p=0.002). Laminin and YKL-40 levels did not allow a useful prediction. Cytokeratin-18 and hyaluronic acid are suitable serum markers predicting liver fibrosis in children with NAFLD. Studying these markers may identify patients at risk of disease progression.

Non-alcoholic fatty liver disease (NAFLD) is a liver manifestation of metabolic syndrome since obesity and insulin resistance are the main pathogenic contributors for both conditions. NAFLD carries increased risk of atherosclerosis and cardiovascular diseases. There is an urgent need to find effective and safe therapy for children and adults with NAFLD. Data from research and clinical studies suggest that omega-3 fatty acids may be beneficial in metabolic syndrome-related conditions and can reduce the risk of cardiovascular disease. We are conducting a randomized, multicenter, double-blind, placebo-controlled trial of treatment with omega-3 fatty acids in children with NAFLD. Patients are randomized to receive either omega-3 fatty acids containing docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) or placebo for 24 weeks. The dose of omega-3 (DHA+ EPA) ranges from 450 to 1300 mg daily. Low calorie diet and increased physical activity are advised and monitored using validated questionnaires. The primary outcome of the trial is the number of patients who decreased ALT activity by ≥ 0,3 of upper limit of normal. The main secondary outcomes are improvement in the laboratory liver tests, liver steatosis on ultrasound, markers of insulin resistance and difference in fat/lean body mass composition after 6 months of intervention. Potential efficacy of omega-3 fatty acids in the treatment of NAFLD will provide needed rationale for use of this safe diet supplement together with weight reduction therapy in the growing population of children with NAFLD. NCT01547910

Hepatic lipid accumulation is closely related to the development of insulin resistance, which is regarded as one of the most significant risk factors of nonalcoholic fatty liver disease (NAFLD). Although the exact molecular pathway leading to impaired insulin signaling has not been definitively established, ceramides are suspected mediators of lipid induced hepatic insulin resistance. Therefore, the aim of the study was to evaluate the serum ceramides concentration in obese children with NAFLD. The prospective study included 80 obese children (aged 7–17 years, median 12 years) admitted to our Department to diagnose initially suspected liver disease. Patients with viral hepatitis (HCV, HBV, CMV), autoimmune (AIH), toxic and metabolic (Wilson’s disease, alfa-1–antitrypsin deficiency) liver diseases and celiac disease were excluded. NAFLD was diagnosed based on pediatric diagnostic criteria in obese children with liver steatosis in ultrasound (US) as well as elevated alanine transaminase (ALT) serum activity after exclusion of other major liver diseases listed before. Ultrasonography was used as a screening method and for qualitative assessment of the steatosis degree (graded according to Saverymuttu scale). Advanced steatosis was defined as a score > 1. The total intrahepatic lipid content (TILC) was assessed by magnetic resonance proton spectroscopy (1HMRS) which is the most accurate technique for assessment of ectopic fat accumulation. Fasting serum concentration of ceramides was measured in 62 children. NAFLD was diagnosed in 31 children. Significant, positive correlation was found between total serum concentration of ceramides and insulin (r = 0.3, p = 0.02) and HOMA-IR (r = 0.28, p = 0.03). Total ceramide concentration as well as specific fatty acid-ceramides (FA-ceramides) concentrations, namely: myristic, palmitic, palmitoleic, stearic, oleic, behenic and lignoceric were significantly higher (p = 0.004, p = 0.003, p = 0.007, p < 0.001, p = 0.035, p = 0.008, p = 0.003, p = 0.006, respectively) in children with NAFLD compared to controls (n = 14). Moreover, children with NAFLD had significantly higher activity of ALT (p < 0.001) and GGT (p < 0.001), HOMA-IR (p = 0.04), BMI (p = 0.046), waist circumference (p = 0.01) steatosis grade in ultrasound (p < 0.001) and TILC in 1HMRS (p < 0.001) compared to children without NAFLD. We did not find significant differences in total and FA-ceramide species concentrations between children with mild (grade 1) and advanced liver steatosis in ultrasonography (grade 2–3). Elevated ceramide concentrations in obese patients together with their significant correlation with insulin resistance parameters suggest their association with molecular pathways involved in insulin signaling impairment known to be strongly linked to pathogenesis of non-alcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) is the most common chronic liver disease in the world, which predispose to more serious hepatic conditions. It ranges from simple liver steatosis to nonalcoholic steatohepatitis (NASH), which may progress to cirrhosis, and even end-stage liver disease. Since obesity became one of the most important health concerns wordwide, a considerable increase in the prevalance of NAFLD and other metabolic implications has been observed, both in adults and children. Due to the coexistence of visceral obesity, insulin resistance, dyslipidemia, NAFLD is considered to be the hepatic manifestation of metabolic syndrome (MetS). These relationships between NAFLD and MetS led to the set up in adults of a new term combining both of these conditions, called metabolic dysfunction-associated fatty liver disease (MAFLD). Based on these findings, we propose a set of criteria, which may be useful to diagnose MAFLD in children and adolescents.