Expert Opinion :
This child has presented with a large liver without any jaundice or signs of liver cell failure. Usually, common causes of hepatomegaly are hepatitis, liver abscesses, chronic liver disease. However, all these will have other symptoms of fever, nausea, vomiting, tender hepatomegaly, ascites, portal hypertension, or even bleeding manifestations. Large liver in an apparently normal child may be suggestive of a storage disorder. The rounded border of the liver is suggestive of some storage in the liver (the liver is filled up and so rounded). Firm liver suggests chronicity and smooth surface says that it is non-cirrhotic.
Among the storage disorders, storage could be of fluid as with congestive cardiac failure or Budd Chiari syndrome, it could be fat as of a fatty liver, it could be glycogen as in a glycogen storage disorder or it could be other lysosomal disorders such as mucopolysaccharidoses (MPS), Gangliosidosis (GM1, & GM2) and Niemann Pick disease. Fluid overload leads to enlargement of the liver with stretching of the liver capsule and hence tender hepatomegaly. In addition, the child would develop ascites if there is fluid overload. Fluid overload states are usually acute and have soft liver. Thus it is unlikely to be a fluid overload state. Fatty liver is usually seen in obesity, metabolic X, and protein-energy malabsorption state. Fatty acid oxidation defects lead to microvesicular fat deposition which is picked up only on histopathology. This child is neither fat nor wasted and does not have any other features of metabolic X disorder and hence fatty liver seems unlikely. Lysosomal disorders present with splenomegaly also, have neurological or bone marrow involvement and even skeletal deformities. This child only has isolated hepatomegaly. Thus, the most likely etiology in this child is Glycogen storage disorder (GSD). There are several types of GSD that affect the liver namely GSD Type I, II, III, IV, VI, IX. Of these type IV usually leads to cirrhosis, type II has in addition heart and muscle involvement (Pompe’s disease), and type VI and IX have additional renal disease. Type I & III usually present with hypoglycemic episodes (more in type I than type III) but maybe absent clinically but may have sub-clinical hypoglycemia and Doll’s facies. In this child, thus one needs to differentiate between type I & type III GSD. The child on workup was found to have type III GSD.