Homozygous familial hypercholesterolemia: specific indication for domino liver transplantation

BACKGROUND: Domino liver transplantation is one possibility to overcome the discrepancy between the small number of liver donors and the long waiting lists. Homozygous familial hypercholesterolemia (FHC) is a genetic disorder of lipoprotein metabolism defined by the absence or small number of functional low-density lipoprotein receptors (LDL-Rs) and the ensuing high levels of serum cholesterol. We report a case of a patient with FHC whose liver was used for domino transplantation in a patient with cirrhosis and hepatocellular carcinoma. METHODS: The patient diagnosed with FHC received the large part of a split liver. The liver of the patient with FHC was then transplanted into the patient with cirrhosis and hepatocellular carcinoma. Quantification of extrahepatic LDL-R was performed by flow cytometry on monocytes, and the gene expression of LDL-R was assayed by reverse transcriptase-polymerase chain reaction on monocyte-derived macrophages and cultured fibroblasts isolated from the patients. RESULTS: One year after surgery, the donor's serum cholesterol (without treatment) was normal, and the recipient's serum cholesterol (with simvastatin treatment) was slightly increased. Quantification of peripheral LDL-R on monocytes isolated from the patients revealed values of 6.7% in the patient with FHC and 71% in the patient with cirrhosis and hepatocellular carcinoma. The reverse transcriptase-polymerase chain reaction assay revealed the presence of gene expression for LDL-R. CONCLUSIONS: Domino transplantation can be efficiently used in a patient with marginal indications for transplantation using a liver from a patient with FHC. The slightly elevated serum cholesterol level in the recipient may be explained by the normal function of extrahepatic LDL-R.