Changes in the patterns and microbiology of spontaneous bacterial peritonitis : analysis of 200 cirrhotic patients

The microbiological characteristics of spontaneous bacterial peritonitis (SBP) are changing worldwide with a shift in patterns of SBP and increasing prevalence of antibiotic-resistant bacteria. We, therefore, conducted this retrospective study aiming to characterise the current patterns and microbiology of SBP in our region.

We performed a retrospective chart review of patients presenting with their first episodes of SBP. The demographical, clinical and laboratory parameters of all patients at first paracentesis were recorded.

The study included 200 cirrhotic patients with SBP. Mean age was 60.4±13.5 years and 116 (58%) patients were males. Liver cirrhosis was predominantly viral in 138 (69%) patients. Ascitic fluid cultures were positive in 103 (51.5%) patients and negative in 97 (48.5%). Ninety-eight (95.1%) patients had monomicrobial bacterial growth. The most common variants of spontaneous ascitic fluid infection were culture negative neutrocytic ascites (CNNA) in 97(48.5%) patients and SBP in 65 (32.5%) patients. E.Coli was most frequently isolated microorganism in 41 (39.8%) patients followed by staphylococcus species in 19 (18.4%) patients, Klebsiella pneumonae in 14(13.6%) patients and streptococcus species in 13 (10.7%) patients. The prevalence of extended spectrum beta-lactamases (ESBL) resistant E.Coli was 29.3%. Antibiotic resistance rate for meropenem, piperacillin\ tazobactam, ceftriaxone and ciprofloxacin was 0%, 22.0%, 29.0%, and 28.6% respectively.

Changes in the patterns and microbiology of SBP are evident in our region with increasing prevalence of culture negative SBP, extended spectrum beta-lactamases resistant E.Coli, and increased resistance rate to first line antibiotics. Our data argue for relying on periodic hospital based antibiotic susceptibility data whenever SBP is treated.