Background/aims: The mannose-binding lectin (MBL) gene was reported to play an important role in determining the clinical outcome of persistent hepatitis B virus (HBV) infection. We investigated serum MBL concentrations and MBL gene mutations to determine whether they were related to the prognosis of patients with fulminant hepatic failure (FHF) caused by HBV infection.
Methods: We investigated serum MBL concentrations and MBL gene mutations in 43 HBV-infected Japanese patients with FHF and 260 HBsAg-negative healthy controls. Serum MBL concentrations were measured by an enzyme-linked immunosorbent assay, and mutations in the MBL gene were analysed by nested PCR and direct DNA sequencing.
Results: Only a mutation in codon 54 of the MBL gene was found. The frequency of this mutation in nonsurvivors (40%, 8/20) was higher than in survivors (13%, 3/23), and the difference was slightly significant (p = 0.043). The H allele frequency in survivors (70.5%, 31/44) was higher than in nonsurvivors (39.5%, 15/38) (p = 0.0048). Because of these factors the mean serum MBL concentration in survivors, 1.61 ,micro/ml (range 0.3-3.86), was significantly higher than in nonsurvivors, 0.79 microg/ml (range 0.04-1.51) (p < 0.0001). The likelihood ratio for nonsurvival was 0 for over 2.0 microg/ml, 0.67 for 1.0-2.0 microg/ml, and 2.24 for 0-1.0 microg/ml.
Conclusions: The mutation in codon 54 of the MBL gene tended to be higher in nonsurvivors than in survivors. The H allele frequency (high producing allele in H/Y) in survivors was higher than that in nonsurvivors. High levels of serum MBL correlated with the survival of patients with FHF due to HBV infection. Serum MBL may be useful as a predictive factor for the survival of patients with FHF caused by HBV.