RESUMEN
BACKGROUND: In patients with cirrhosis, bacterial DNA has been found in ascites reflecting bacterial translocation. However, the clinical relevance of this finding is ill-defined especially compared with the standard diagnostics for detection of spontaneous bacterial peritonitis (SBP). Furthermore, other DNA tests have not been sufficiently evaluated. PATIENTS AND METHODS: We prospectively included 151 patients with cirrhosis and ascites admitted to our department. The patients were evaluated for diagnosis of SBP (polymorphonuclear count > 250 cells/mm) or finding of bacterascites, defined by positive bacterial culture from ascites. To detect bacterial species of bacterial DNA fragments in ascites, broad-range polymerase chain reaction and nucleotide sequencing analysis with the LightCycler SeptiFast Kit Mgrade were performed. Routine parameters were correlated with these findings. RESULTS: Eighteen of 151 patients (12%) had SBP according to the classic definition. Bacterial DNA was detected in five of these 18 patients (3%), whereas in 13 patients (9%), bacterial DNA was detected without standard SBP. Seven patients (5%) had culture-positive SBP, only in two of them bacterial DNA was detected. In multivariate analysis, C-reactive protein (P = 0.000), white blood cell count (P = 0.019), and lactic acid dehydrogenase in ascites (P = 0.000) were independently associated with SBP. In the DNA-positive ascites group, none of the assessed parameters was significantly associated with the bacterial DNA positivity. CONCLUSION: We found no correlation between detection of bacterial DNA in ascites and SBP (polymorphonuclear count > 250/mm). In contrast to the patients with bacterial DNA in ascites, patients with SBP showed clinical signs of infection. This study provides no evidence that detection of bacterial DNA in ascites of patients with liver cirrhosis is of clinical or diagnostic relevance when using the panel of LightCycler SeptiFast Kit Mgrade.
Asunto(s)
Líquido Ascítico/microbiología , Traslocación Bacteriana , ADN Bacteriano/aislamiento & purificación , Cirrosis Hepática/microbiología , Peritonitis/diagnóstico , Peritonitis/microbiología , Reacción en Cadena de la Polimerasa , Juego de Reactivos para Diagnóstico , Adulto , Anciano , Técnicas Bacteriológicas , Distribución de Chi-Cuadrado , ADN Bacteriano/sangre , Femenino , Humanos , Estimación de Kaplan-Meier , Cirrosis Hepática/complicaciones , Cirrosis Hepática/mortalidad , Masculino , Persona de Mediana Edad , Peritonitis/mortalidad , Valor Predictivo de las Pruebas , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia , Suiza , Factores de TiempoRESUMEN
UNLABELLED: Spontaneous bacterial peritonitis (SBP), a severe complication in patients with advanced liver cirrhosis, has been attributed to bacterial translocation from the intestine. Variants of the NOD2 (nucleotide-binding oligomerization domain containing 2) gene have been associated with impaired mucosal barrier function in Crohn disease. We hypothesized that the risk of acquiring SBP is increased in patients with cirrhosis carrying NOD2 variants. We recruited 150 nonselected patients with liver cirrhosis and ascites admitted to our unit, monitored survival, and recorded the development of SBP prospectively and retrospectively. SBP was defined as the presence of polymorphonuclear neutrophil (PMN) cells >250 per microL of ascitic fluid. Patients were genotyped for the NOD2 variants p.R702W, p.G908R, and c.3020insC. During a median follow-up of 155 days, 54 patients (36%) died and SBP was diagnosed in 30 patients (20%). The occurrence of SBP was increased significantly (P = 0.008) in carriers of NOD2 variants (odds ratio [OR] = 3.06). Retrospectively, SBP was observed in 22 additional patients, and the combined prospective and retrospective analysis substantiated the association between NOD2 and SBP (P = 0.004; OR = 2.98). Of note, carriers of NOD2 risk alleles showed a significantly (P = 0.007) reduced mean survival time (274 days) in comparison to patients with wildtype genotypes (395 days). CONCLUSION: Common NOD2 variants linked previously to impaired mucosal barrier function may be genetic risk factors for death and SBP. These findings might serve to identify patients with cirrhotic ascites eligible for preemptive antibiotic treatment.