Pathogens of spontaneous bacterial peritonitis change in northern China.

Objective: To determine the identity of microorganisms isolated from patients diagnosed with spontaneous bacterial peritonitis (SBP).

Methods: We reviewed cases diagnosed with SBP over a 14-year period. The medical records of 780 SBP-diagnosed patients with decompensated cirrhosis and ascites admitted to Tangdu Hospital, Xian, Shaanxi Province, China were retrospectively reviewed between January 1996 and December 2009. The patients were placed into 2 groups, and the clinical data were compared between the 2 groups. Ascitic fluid was collected from these patients and cultured for bacteria using the MicroScan WalkAway 40 system.

Results: There was a significant difference in the ratio of pathogens between group A (48 patients, from January 1996 to December 2002) and group B (50 patients, from January 2003 to December 2009) (χ²=9.630, p=0.002). The SBP patients with gram-positive bacteria needed significantly more antibiotics within 30 days compared to those with gram-negative bacteria (χ²=12.285, p=0.000).

Conclusion: In recent years, the types of isolated pathogens have significantly changed in northern China. Such changes have also been observed in other countries and have been attributed to long-term antibiotic therapy and invasive procedures. Changes in the epidemiology of pathogens that cause SBP must be monitored for optimal treatment.