Pediatric nonalcoholic fatty liver disease: A clinical and laboratory challenge

Abstract

The true prevalence of pediatric nonalcoholic fatty liver disease (NAFLD) is unknown. Challenges in determining the population prevalence of NAFLD include the type of test (and the reference intervals used to define normal and abnormal), the type of population (general population, hospital series), the demographic characteristics of the population sampled, and the nature of the study design. The natural history of pediatric NAFLD remains uncertain. The issue of when to perform a liver biopsy in children with suspected NAFLD remains controversial. Children with NAFLD but normal alanine aminotransferase are rarely investigated. However, evidence of alterations in glucose metabolism parameters should prompt a better understanding of the natural history of pediatric NAFLD not only in terms of the progression of liver disease but also regarding its potential relationship with other health outcomes such as type 2 diabetes mellitus and cardiovascular disease. This evidence could make liver biopsy mandatory in the majority of cases at risk of progressive and severe hepatic and extrahepatic disease. This conclusion, however, raises the question of the feasibility of liver biopsy assessment in an extremely large at risk population, and of the cost/effectiveness of this policy. There is a considerable, continuous interest in reliable, noninvasive alternatives that will allow the prognosis of pediatric NAFLD to be followed in large community or population-based studies.

Changes of liver fat content and transaminases in obese children after 12-mo nutritional intervention

“…The sensitivity of this biochemical marker, however, remains low because a number pediatric patients may present ALT values in the normal range [29] . Moreover, given the clinical relevance of identifying children with steatohepatitis (NASH), several studies have described biomarkers associated with pediatric NASH [29,30] . Patton et al [30] , evaluating clinical relation of histopathology with transaminases in pediatric NAFLD, found that AST was superior to ALT in distinguishing NAFLD patterns, while other studies showed ALT performing better [12,15,24] .…”

“…Patton et al [30] , evaluating clinical relation of histopathology with transaminases in pediatric NAFLD, found that AST was superior to ALT in distinguishing NAFLD patterns, while other studies showed ALT performing better [12,15,24] . Indeed, it is now widely accepted that the degree of ALT elevation does not correlate with the presence or severity of histological findings of NAFLD [29] . For this reason in the present study we considered not only the transaminases value at baseline and at the end of treatment but also the change.…”

“…Serum ALT activity is a widely available and inexpensive test for the screening and initial evaluation of NAFLD [29] . The sensitivity of this biochemical marker, however, remains low because a number pediatric patients may present ALT values in the normal range [29] .…”

“…Serum ALT activity is a widely available and inexpensive test for the screening and initial evaluation of NAFLD [29] . The sensitivity of this biochemical marker, however, remains low because a number pediatric patients may present ALT values in the normal range [29] . Moreover, given the clinical relevance of identifying children with steatohepatitis (NASH), several studies have described biomarkers associated with pediatric NASH [29,30] .…”

Cholesterol and Inflammation at the Crossroads of Non-Alcoholic Fatty Liver Disease (NAFLD) and Atherogenesis

“…For instance, the prevalence of obesity among US children has tripled in just one decade, rising from 5 % in 1980 to 15 % in 1990 and is currently around 17 %(Centers for Disease Control and Prevention CDC, 2011). The estimates of NAFLD prevalence in childhood have risen accordingly and are already between 2.6 and 9.6 % among the general pediatric population (Pacifico et al, 2010), reaching 68 % in obese children (Fu et al, 2011). Most cases of NAFLD arise in the detrimental environment of various metabolic disorders commonly known as the metabolic syndrome.…”