Altered striatal dopamine D2 receptor density and dopamine transport in a patient with hepatic encephalopathy

A patient suffering from liver cirrhosis presented with a bradykinetic-rigid syndrome suspected as Parkinson's disease. A detailed work-up of the case revealed hepatic encephalopathy as the cause of the neurological symptomatology. An alteration of striatal dopamine D-2 receptor binding and dopamine re-uptake sites was demonstrated by I-123-iodobenzamide (IBZM) and I-123-beta -CIT single photon emission computed tomography (SPECT), respectively. It is suggested that the alteration of the dopamine re-uptake in cirrhotics may be the cause of an increased catabolism of dopamine in HE.