RESUMO
INTRODUCTION AND OBJECTIVES: Assessment of liver biopsy sample adequacy criteria is essential to avoid sampling errors in patients with diffuse liver pathology. Many studies have evaluated these criteria in adults; however, no previous studies have been performed on neonatal liver disorders. We aimed to assess the adequacy criteria of Tru-cut needle liver biopsy samples in infants with neonatal cholestasis (NC). METHODS: In a retrospective analysis of infants who underwent liver biopsy for NC within a one-year duration, 58 specimens were recruited. The core lengths after fixation were measured. All samples were acquired with a 16-gauge (G) Tru-cut needle. Serial shortening of these samples was performed to define the smallest core length that gives representative parenchyma that could determine the activity grade and fibrosis stage reported by larger cores. RESULTS: It was found that a 4-mm core length with a complete portal tract (CPT) number of 8±3 could adequately assess the NC activity grade. In addition, a 6-mm core length with a CPT number of 11±3 could adequately estimate NC fibrosis stage. CONCLUSIONS: The adequacy criteria of liver tissue samples for the accurate assessment of NC are different from those defined for adult diffuse liver pathology. At least a 4-mm core length with a CPT number of 8±3 and a 6-mm core length with a CPT number of 11±3 acquired by a 16-G Tru-cut needle should be used to assess NC activity grade and fibrosis stage, respectively.