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Objective.Lack of access to polarized light microscopy is often cited as an argument to justify the clinical diagnosis of crystal-related arthritis. We assessed the influence of time since sampling and preservation methods on crystal identification in synovial fluid (SF) samples under polarized light microscopy.Methods.This was a prospective, longitudinal, observational factorial study, analyzing 30 SF samples: 12 with monosodium urate (MSU) crystals and 18 with calcium pyrophosphate (CPP) crystals. Each SF sample was divided into 4 subsamples (120 subsamples in total). Two were stored in each type of preserving agent, heparin or ethylenediamine tetraacetic acid (EDTA), at room temperature or at 4°C. Samples were analyzed the following day (T1), at 3 days (T2), and at 7 days (T3) by simple polarized light microscopy, and the presence of crystals was recorded.Results.The identification of crystals in the MSU group was similar between groups, with crystals observed in 11/12 (91.7%) room temperature samples and in 12/12 (100%) refrigerated samples at T3. Identification of CPP crystals tended to decrease in all conditions, especially when preserved with EDTA at room temperature [12/18 (66.7%) at T3], while less reduction was seen in refrigerated heparin-containing tubes.Conclusion.Preserving samples with heparin in refrigerated conditions allows delayed microscopic examination for crystals. Avoiding crystal-proven diagnosis because of the immediate unavailability of microscopy no longer appears justified.

Background Bacterial infections are common complications arising in patients with cirrhosis and ascites. Trans-location of bacterial DNA is a dynamic process that is associated with an increased inflammatory response and apoor prognosis in this setting. The aim of this study was to study whether peritoneal macrophages remain in achronic primed status to allow a rapid response to subsequent events of bacterial translocation.Patients and methods Peritoneal monocyte-derived macrophages were isolated from 25 patients with cirrho-sis and non-infected ascites and compared with donor’s blood monocytes. Activation cell-surface markers werescreened using flow-cytometry, and the phosphorylation state of ERK 1⁄2, p38 MAP Kinase, PKB⁄Akt and tran-scription factors c-Jun and p65 NFjB were evaluated using Western blot. Synthesis of tumour necrosis factoralpha, interleukin 6 (IL-6) and interleukin-10 (IL-10) at baseline and in response to bacterial stimuli was evaluatedusing ELISA.Results A high expression of CD54, CD86 and HLA-DR at baseline was displayed by peritoneal macrophages.Increased phosphorylated levels of ERK1⁄2, protein kinase B (PKB) and c-Jun, together with IL-6 production,were observed in peritoneal macrophages at baseline compared with donors’ blood monocytes. A positive corre-lation was established between basal IL-6 levels and extracellular signal-regulated kinase (ERK) phosphorylationin peritoneal macrophages from patients with cirrhosis (r =0AE9; P =0AE005). Addition of lipopolysaccharideinduced higher phosphorylation levels of all studied signalling intermediates than synthetic-oligodeoxydinucleo-tides, but similar end-stage p65 NFjB.Conclusions A sustained immune response is present in ascitic fluid of cirrhotic patients, even in the temporalabsence of bacterial antigens. This would facilitate a fast response, probably controlled by IL-6, against repeatedbacterial-DNA translocation or in liver chronic inflammation.Keywords Ascitic fluid, cirrhosis, cytokines, macrophages, MAP kinases.Eur J Clin Invest 2011; 41 (1): 8–15

Bacterial translocation in patients with cirrhosis induces a marked proinflammatory activity that may be different against viable bacteria or bacterial products. The aim of this study is to identify new markers of bacterial translocation by investigating bacterial-driven peptides and correlate their presence with the inflammatory response. Patients with cirrhosis and ascites were included. An analysis by two-dimensional polyacrylamide gel electrophoresis of ascitic fluid total protein from patients (n = 47) and from frequently detected bacterial strains was performed. Two-dimensional maps were digitally compared. The identification of possible markers was performed by mass spectrometry. TNF-alpha, IFN-gamma, IL-12, nitric oxide, and proteins of the complement and lipopolysaccharide-binding protein levels were measured in ascitic fluid samples of patients by enzyme-linked immunosorbent assay. Patients were distributed according to the presence (group I, n = 16) and absence (group II, n = 31) of serum and ascitic fluid bacterial DNA. Among clinical and analytical differences between groups, only mean arterial pressure was significantly higher in patients from group II. Identified bacterial peptides were associated with bacterial protection against immune defenses and included glyceraldehyde-3-phosphate dehydrogenase A, Porin OmpC, and HSP60. Eight patients from group I also showed bacterial peptides, whereas none from group II did. All studied mediators of immune activation were significantly higher in patients with bacterial DNA than in patients without bacterial DNA. TNF-alpha, IFN-gamma, and proteins of the complement were significantly increased in patients with bacterial peptides versus those without bacterial peptides. Bacterial peptide translocation is present in the ascitic fluid of a subgroup of patients with advanced cirrhosis and is associated with an increased immune response.

Bacterial infections and severity of associated inflammatory reaction influence prognosis in patients with advanced cirrhosis. We compared the innate immune response to bacterial DNA (bactDNA) translocation with that caused by viable bacteria translocation in patients with spontaneous bacterial peritonitis and the relationship between the cytokine response and serum levels of bactDNA. The bactDNA translocation was investigated in 226 patients with cirrhosis and noninfected ascites, 22 patients with spontaneous bacterial peritonitis, and 10 patients with ascites receiving continuous norfloxacin. Serum and ascitic fluid tumor necrosis factor α, interferon-γ, interleukin-12, and nitric oxide metabolites were measured via enzyme-linked immunosorbent assay. Bacterial genomic identifications were made via amplification and sequencing of the 16S ribosomal RNA gene and digital quantization with DNA Lab-on-chips. The bactDNA was present in 77 noninfected patients (34%) and in all cases of spontaneous bacterial peritonitis, even in those with culture-negative ascitic fluid. No patient receiving norfloxacin showed bactDNA translocation. Levels of all cytokines were similar in patients with bactDNA translocation or spontaneous bacterial peritonitis and significantly higher than in patients without bactDNA or in those receiving norfloxacin. Serum bactDNA concentration paralleled levels of all cytokines and nitric oxide in a series of patients with bactDNA translocation or spontaneous bacterial peritonitis followed during 72 hours. Antibiotic treatment in the series of patients with spontaneous bacterial peritonitis did not abrogate bactDNA translocation in the short term. Conclusion: bactDNA translocation-associated cytokine response is indistinguishable from that in patients with spontaneous bacterial peritonitis and is dependent on bactDNA concentration. Norfloxacin abrogates bactDNA translocation and cytokine response. (HEPATOLOGY 2008;47:978–985.)

Summary Translocation of bacterial-DNA in patients with cirrhosis and ascites triggers an innate immune response. Identification of characteristics to which this response is sensitive is relevant from a clinical standpoint. The aim of this study has been to determine if the proinflammatory immune response established in vivo in cirrhotic patients with ascites as a consequence of bacterial-DNA translocation is related to the identified bacterial species and their frequency of cytosine-guanosine content in serum and ascitic fluid. Patients with advanced cirrhosis and ascites were included in the study and distributed into groups I and II according to the absence or presence of bacterial-DNA translocation, respectively. Serum and ascitic fluid levels of proinflammatory cytokines after normalization of bacterial-DNA concentration and the activated form of nuclear factor-kappa B in ascitic fluid pellets were measured by enzyme-linked immunosorbent assay techniques. Translocation of bacterial-DNA with higher cytosine-guanosine content induced the highest cytokine response, which was higher than that in patients without bacterial-DNA translocation. The activated form of nuclear factor-kappa B in ascitic fluid pellets of patients with bacterial-DNA translocation was greater in patients with higher bacterial-DNA cytosine-guanosine content, whereas the amount of total nuclear factor-kappa B remained unaltered. Bacterial-DNA translocation induces a marked immune reaction in vivo in patients with advanced cirrhosis and ascites which is related, among other factors, to the bacterial-DNA cytosine-guanosine content. Therefore, the host's immune response to bacterial-DNA translocation constitutes a species-specific phenomenon.

Translocation of intestinal bacteria to ascitic fluid is, probably, the first step in the development of spontaneous bacterial peritonitis in patients with cirrhosis. Proteins of the complement system are soluble mediators implicated in the host immune response to bacterial infections and its activation has been traditionally considered to be an endotoxin-induced phenomenon. The aim of this study was to compare the modulation of these proteins in response to the presence of bacterial DNA and/or endotoxin in patients with advanced cirrhosis and ascites in different clinical conditions. Groups I and II consisted of patients without/with bacterial DNA. Group III included patients with spontaneous bacterial peritonitis and Group IV with patients receiving norfloxacin as secondary long-term prophylaxis of spontaneous bacterial peritonitis. Serum and ascitic fluid levels of endotoxin and truncated residues of the complement system were measured by ELISA. The complement system is triggered in response to bacterial DNA, as evidenced by significantly increased levels of C3b, membrane attack complex, and C5a in patients from Groups II and III compared with patients without bacterial DNA (Group I) and those receiving norfloxacin (Group IV). Gram classification did not further differentiate the immune response between patients within groups II and III, even though endotoxin levels were, as expected, significantly higher in patients with bacterial DNA from gram-negative microorganisms. The complement protein activation observed in patients with bacterial DNA in blood and ascitic fluid is indistinguishable from that observed in patients with spontaneous bacterial peritonitis and may occur in an endotoxin-independent manner.

Bacterial infections are common complications arising in patients with cirrhosis and ascites. Translocation of bacterial DNA is a dynamic process that is associated with an increased inflammatory response and a poor prognosis in this setting. The aim of this study was to study whether peritoneal macrophages remain in a chronic primed status to allow a rapid response to subsequent events of bacterial translocation.Peritoneal monocyte-derived macrophages were isolated from 25 patients with cirrhosis and non-infected ascites and compared with donor's blood monocytes. Activation cell-surface markers were screened using flow-cytometry, and the phosphorylation state of ERK 1/2, p38 MAP Kinase, PKB/Akt and transcription factors c-Jun and p65 NFκB were evaluated using Western blot. Synthesis of tumour necrosis factor alpha, interleukin 6 (IL-6) and interleukin-10 (IL-10) at baseline and in response to bacterial stimuli was evaluated using ELISA.A high expression of CD54, CD86 and HLA-DR at baseline was displayed by peritoneal macrophages. Increased phosphorylated levels of ERK1/2, protein kinase B (PKB) and c-Jun, together with IL-6 production, were observed in peritoneal macrophages at baseline compared with donors' blood monocytes. A positive correlation was established between basal IL-6 levels and extracellular signal-regulated kinase (ERK) phosphorylation in peritoneal macrophages from patients with cirrhosis (r=0·9; P=0·005). Addition of lipopolysaccharide induced higher phosphorylation levels of all studied signalling intermediates than synthetic-oligodeoxydinucleotides, but similar end-stage p65 NFκB.A sustained immune response is present in ascitic fluid of cirrhotic patients, even in the temporal absence of bacterial antigens. This would facilitate a fast response, probably controlled by IL-6, against repeated bacterial-DNA translocation or in liver chronic inflammation.

Background: The pathogenesis of inflammatory bowel disease (IBD) involves the interaction between genetic susceptibility, mucosal immunity, and intestinal bacteria. Bacterial translocation is a common event in these patients and plays an important role in the perpetuation of chronic intestinal inflammation. Blood microbiological cultures, however, are frequently negative. The aim was to evaluate the presence of bacterial DNA (bactDNA) and the associated cytokine response in patients with IBD. Methods: Fifteen healthy donors, 29 patients with ulcerative colitis (UC), and 33 patients with Crohn's disease (CD) were studied. The presence of bactDNA was pursued by PCR followed by nucleotide sequencing analysis. Microbiological cultures were carried out among all controls and patients. Cytokine serum levels were measured by enzyme-linked immunosorbent assay (ELISA). Results: BactDNA was detected in 14 out of 33 patients with CD (42.4%) and in 15 out of 29 patients with UC (51.7%). BactDNA translocation was present in 7 out of 21 (33%) and in 10 out of 15 (34%) patients with CD and UC in remission, respectively. None of healthy controls showed bactDNA in serum. A statistically significant increase in all Th1-derived cytokines in CD but not in UC patients with the presence of bactDNA was observed in comparison with patients without bactDNA and controls. Conclusions: BactDNA is present in IBD patients, irrespective of their disease activity. This fact is associated with a marked Th1-driven immune reaction in CD patients, even in those in remission. Whether bactDNA is inducing or is favored by an increased inflammatory scenario in these patients remains under discussion. (Inflamm Bowel Dis 2008)

Patients with cirrhosis undergoing selective intestinal decontamination with norfloxacin show a reduction in serum cytokine levels, probably because of a combined effect of norfloxacin on bowel flora and neutrophils.Thirty-one patients with cirrhosis receiving norfloxacin (400 mg/day) were included. Blood samples were collected at 0.5-4 hours (peak samples group, n = 47) and at 22-24 hours (trough samples group, n = 84) after dose. Fifty-nine ascitic fluid samples were obtained. Single doses of norfloxacin and trimethoprim/sulfamethoxazole were administered to 13 and 5 patients, respectively, (temporal profile group) and samples were collected at 0, 0.5, 1, 1.5, 2, 4, and 24 hours. Norfloxacin, trimethoprim/sulfamethoxazole, cytokines, nitric oxide, expression levels of nuclear factor (NF)-kappaB and inhibitor of NF-kappaB (IkB-alpha), neutrophil oxidative burst, and rate of apoptotic events were determined.All samples were bacterial DNA negative and had no significant levels of lipopolysaccharide. Serum and ascitic levels of tumor necrosis factor-alpha, interferon-gamma, interleukin-12, and nitric oxide were significantly lower in peak than in trough samples. A correlation was present between serum norfloxacins concentrations and tumor necrosis factor-alpha (r = -0.68; P.001), interferon-gamma (r = -0.66; P.001), interleukin-12 (r = -0.66; P.001), and nitric oxide (r = -0.68; P.001). Serum norfloxacin's highest concentrations (1 +/- 0.5 microg/mL) were achieved at 1-2 hours and concurred in time with the lower levels of cytokines and nitric oxide. Intracellular norfloxacin's highest levels (2 +/- 1 microg/mL/10(7) cells) were observed at 2 hours and concurred with a lower NF-kappaB expression, a reduced anion superoxide generation, and apoptotic rate in response to phorbol myristate acetate. Trimethoprim/sulfamethoxazole did not significantly modulate cytokine expression.Norfloxacin but not trimethoprim/sulfamethoxazole modulates inflammatory response and directly affects neutrophils in patients with cirrhosis.