Fatigue is a common symptom in primary biliary cirrhosis (PBC). It can affect individuals at all stages of disease.
However, the pathogenesis of fatigue in PBC is unknown.
In this study, investigators from England examined the hypothesis that a central nervous system (CNS) abnormality related to cholestasis underlies this symptom.
|The globus pallidus magnetisation transfer ratio was reduced in pre-cirrhotic PBC patients.|
The team evaluated 14 patients with pre-cirrhotic PBC, 4 patients with stage III to IV PBC, and 11 healthy women.
They used cerebral magnetization contrast imaging and proton magnetic resonance spectroscopy (MRS).
The investigators determined that the globus pallidus magnetisation transfer ratio (MTR) was significantly reduced in pre-cirrhotic PBC patients compared with healthy controls. This is a quantifiable tissue characteristic that may be abnormal in the presence of normal magnetic resonance imaging.
The team found that the measurements correlated with blood manganese levels. Levels were found to be abnormal in fatigued subjects.
However, there were no differences in MRS measurements between the 3 study groups. The team suggested that the abnormal MTR was not related to hepatic encephalopathy.
Dr Forton's team concluded, "This study suggests that impairments in liver function in PBC may adversely affect the brain long before the development of cirrhosis and hepatic encephalopathy, possibly as a result of altered manganese homeostasis within the CNS".