Anemia on CBC. Elevated transaminases. CT brain showed cortical atrophy. The MRI brain showed white matter lesions. CSF showed increased proteins and mononuclear cells. Biochemistry showed elevated AST, ALT, LDH, gamma-GT, bilirubin, and triglycerides. Liver biopsies showed cholestasis. Normal BMAT. A mutation in RAB27A was not found. Diagnosis was made on impaired NK cell-mediated cytotoxicity by flow cytometry. This evidence concerns the gene GPT and cholestasis.