Monocyte chemotactic protein-1 gene polymorphism and spontaneous bacterial peritonitis

Abstract

I read with great interest the article by Gäbele et al published in issue 44 of World J Gastroenterol 2009. The results of their study indicate that -2518 Monocyte chemotactic protein-1 (MCP-1) genotype AA is a risk factor for spontaneous bacterial peritonitis in patients with alcoholic cirrhosis. However, there are some items that need to be discussed.

Key Words: Spontaneous bacterial peritonitis; Monocyte chemotactic protein-1; Polymorphism

TO THE EDITOR

I read with great interest the article by Gäbele et al[1] published in issue 44 of World J Gastroenterol 2009. The article provides important data. The results of their study indicate that the -2518 Monocyte chemotactic protein-1 (MCP-1) genotype AA is a risk factor for spontaneous bacterial peritonitis (SBP) in patients with alcoholic cirrhosis. The authors suggested that the reduced MCP-1 ascites level may a cause for patients with SBP compared to those with G allele. However, there are some items that need to be discussed. It is debatable to get this conclusion unless ascites MCP-1 levels are measured before and after the treatment of SBP. It has been reported that the MCP-1 level in both sera and ascites is higher in SBP than in non-SBP patients, and decreases after treatment[2]. Infection other than SBP data is also missed in that article. For example, urinary tract infection and even asymptomatic bacteriuria may precede SBP. It is not easy to decide if MCP-1 polymorphism causes urinary tract infection and subsequently SBP, because MCP-1 plays a role even in asymptomatic bacteriuria[3]. Another issue of my concern is the number of SBP episodes. No data in relation with repeated SBP were provided in the article. Did the authors observe repeated SBP episodes in the patients with genotype AA over a 6-year period between 2001-2007? Did the patients respond to the antibiotic therapy well in a similar time interval?