Liver, Hepatocyte - Hypertrophy


comment:
Hepatocyte hypertrophy is a form of cytologic alteration that is diagnosed based on an observable increased size of hepatocytes compared with concurrent control liver. It is most readily apparent when it has the commonly occurring centrilobular distribution pattern; when it is panlobular, comparison with concurrent controls can provide diagnostic confirmation. When mild, detection of hepatocyte hypertrophy may be difficult, but its identification is facilitated at low magnification.Hepatocyte hypertrophy is commonly associated with microsomal enzyme induction secondary to exposure to certain xenobiotics ( Figure 1








A narrow centrilobular zone of hepatocyte hypertrophy is present in Figure 7




recommendation:
Hepatocyte hypertrophy should be diagnosed and graded whenever present. Subtle cases may be difficult to diagnose, and in many instances, comparison with concurrent controls is necessary to confirm the diagnosis. If hypertrophy is suspected but not clear-cut, then a blind evaluation of the slides comparing the relevant dose groups with controls is appropriate. Accompanying increases in liver weight may provide some comfort in diagnosis when the change is marginal. When possible, the diagnosis of hepatocyte hypertrophy should be qualified with a distribution pattern and given a qualitative severity grade. If the hepatocytes are enlarged due to the presence of cytoplasmic vacuoles or inclusions, hypertrophy should not be diagnosed; rather, the cytoplasmic vacuolization or cytoplasmic inclusions should be recorded, unless there is other, definitive evidence of hypertrophy.references:
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