Apoptosis markers in liver biopsy of non-alcoholic steatohepatitis in pediatric patients.

VALVA P; DE MATTEO E; GALOPPO M; PEDREIRA A; GALOPPO MC; PRECIADO MV

Brasil

Congreso; III World Congress of Pediatric Gastroenterology, Hepatology and Nutrition; 2008

European Society for Paediatric Gastroenterology Hepatology and Nutrition y North American Society for Pediatric Gastroenterology, Hepatology and Nutrition.

The natural history of pediatric non-alcoholic steatohepatitis (NASH) is still unknown; however there have been described histological differences between adult and pediatric cases. Apoptosis may play an important role in pathophysiological pathways involved in liver damage and progression. Our aim was to detect early apoptosis markers, activated caspase-3 (casp-3a) and caspase-generated cytokeratin-18 fragment (M30), in hepatocytes and to correlate their presence with clinical, serological and histological characteristics in pediatric NASH. Twenty-five liver biopsies from NASH patients [median age: 11 years (range 18 mo-18 yrs); 68% male] and 8 control (congenital liver fibrosis) were evaluated. Records were reviewed for serum AST, ALT, cholesterol, triglycerides and body mass index (BMI). Samples were semi-quantitatively graded for activity (steatosis, inflammation and ballooning) and fibrosis. Casp-3a and M30 were evaluated by immunohistochemistry. Results were expressed as n° positive hepatocytes/n° total hepatocytes in 20 high-power fields (´1000). BMI was elevated in 92% cases (44% obese, 48% overweighed). Serum AST and ALT at time of biopsy were elevated in 32% and 68% cases, respectively. Abnormal lipid profile was found in 77% of patients. Sixty percent of biopsies presented lobular steatosis grade 3, 84% lobular inflammatory activity grade 1, 72 % grade 1 ballooning and 76% fibrosis stage 3. Only one patient had cirrhosis. Our series shared histological characteristics of both adult and pediatric types previously described. On H&E stained sections, non-apoptotic cells were identified. M30 staining [median: 0.041 (0.003-0.20)] was associated with milder fibrosis (p= 0.02) and inflammation (p=0.07) but not with steatosis. Casp-3a detection [median: 0.11 (0.004-0.26)] was also associated with low inflammatory grade (p=0.03) but not with fibrosis and steatosis. Controls did not show M30 and casp-3a staining. This study reveals interesting differential features regarding to NASH histological characteristics and apoptosis markers compared with previous adult reports. Casp-3a and M30 staining enhances detection of apoptotic cells compared with H&E. Apoptosis association with mild fibrosis and inflammation, but not with steatosis may suggest that it is an early event in the course of the histological damage progression. Measurement of different components of the apoptotic pathway may represent useful markers to understand the pathogenesis of NASH.´1000). BMI was elevated in 92% cases (44% obese, 48% overweighed). Serum AST and ALT at time of biopsy were elevated in 32% and 68% cases, respectively. Abnormal lipid profile was found in 77% of patients. Sixty percent of biopsies presented lobular steatosis grade 3, 84% lobular inflammatory activity grade 1, 72 % grade 1 ballooning and 76% fibrosis stage 3. Only one patient had cirrhosis. Our series shared histological characteristics of both adult and pediatric types previously described. On H&E stained sections, non-apoptotic cells were identified. M30 staining [median: 0.041 (0.003-0.20)] was associated with milder fibrosis (p= 0.02) and inflammation (p=0.07) but not with steatosis. Casp-3a detection [median: 0.11 (0.004-0.26)] was also associated with low inflammatory grade (p=0.03) but not with fibrosis and steatosis. Controls did not show M30 and casp-3a staining. This study reveals interesting differential features regarding to NASH histological characteristics and apoptosis markers compared with previous adult reports. Casp-3a and M30 staining enhances detection of apoptotic cells compared with H&E. Apoptosis association with mild fibrosis and inflammation, but not with steatosis may suggest that it is an early event in the course of the histological damage progression. Measurement of different components of the apoptotic pathway may represent useful markers to understand the pathogenesis of NASH.