Molecular detection of monocyte chemotactic protein-1 polymorphism in spontaneous bacterial peritonitis patients.

AIM: To investigate the association of the functional monocyte chemotactic protein-1 (MCP-1) promoter polymorphism (A-2518G) with spontaneous bacterial peritonitis (SBP).

METHODS: Fifty patients with post-hepatitis C liver cirrhosis and ascites were categorized into two groups; group I included 25 patients with SBP and group II included 25 patients free from SBP. In addition, a group of 20 healthy volunteers were included. We assessed the MCP-1 gene polymorphism and gene expression as well as interleukin (IL)-10 levels in both blood and ascitic fluid.

RESULTS: A significant MCP-1 gene polymorphism was detected in groups I and II (P = 0.001 and 0.02 respectively). Group I was associated with a significantly higher frequency of AG genotype [control 8 (40%) vs SBP 19 (76.0%), P < 0.001], and group II was associated with a significantly higher frequency of GG genotype when compared to healthy volunteers [control 1 (5%) vs cirrhotic 16 (64%), P < 0.001]. Accordingly, the frequency of G allele was significantly higher in both groups (I and II) [control 10 (25%) vs SBP 27 (54%), P < 0.001 and vs cirrhotic 37 (74.0%), P < 0.001, respectively]. The total blood and ascetic fluid levels of IL-10 and MCP-1 gene expression were significantly higher in group I than in group II. Group I showed significant reductions in the levels of MCP-1 gene expression and IL-10 in the whole blood and ascetic fluid after therapy.

CONCLUSION: MCP-1 GG genotype and G allele may predispose HCV infected patients to a more progressive disease course, while AG genotype may increase the susceptibility to SBP. Patients carrying these genotypes should be under supervision to prevent or restrict further complications.