Is detection of bacterial DNA in ascitic fluid of clinical relevance?

Bacterial DNA is a prognostic factor for mortality in patients who recover from spontaneous bacterial peritonitis

Background

Spontaneous bacterial peritonitis (SBP) is associated with a high mortality. The aim was to investigate whether bacterial deoxyribonucleic acid (bactDNA) could offer an accurate identification of pathogens and to explore its prognostic role during and early after an SBP episode.

Methods

Consecutive patients with SBP (SBP-group) and patients with decompensated cirrhosis without SBP/bacterascites (control-group) were enrolled. Standard culture methodology was used to isolate and identify pathogens from blood and ascitic fluid (AF). The SeptiFast test was used to identify bactDNA directly from AF.

Results

Fifty-five patients, median age 60 (interquartile range [IQR] 53-74), model-for-end-stage liver disease (MELD) score 18 (IQR 13-29), with SBP were prospectively included. AF cultures were positive in 52.7% (17.2% drug-resistant bacteria) and bactDNA in 29.1% (58.2% combined sensitivity). BactDNA results were 84.6% concordant with AF cultures. Three patients had positive bactDNA in the culture-negative SBP-group. BactDNA was negative in all 36 of the control group (100% specificity). In multivariate analysis for 7-day survival, factors adversely affecting outcome were MELD (P=0.049) and C-reactive protein (P=0.012). After patients who died during the first week post-admission were excluded, patients with positive bactDNA had a poor prognosis compared to those with a negative test (log-rank P=0.005). Variables independently associated with 30-day mortality were neutrophil-to-lymphocyte ratio (P=0.011) and positive bactDNA (P=0.020).

Conclusions

No evidence was found for the usefulness of bactDNA to improve bacterial identification during an SBP episode. However, bactDNA was a predictor of 30-day mortality in the subset of patients who recovered from the infection episode.

Compartmentalization of Immune Response and Microbial Translocation in Decompensated Cirrhosis

Background: Acquired dysfunctional immunity in cirrhosis predisposes patients to frequent bacterial infections, especially spontaneous bacterial peritonitis (SBP), leading to systemic inflammation that is associated with poor outcome. But systemic inflammation can also be found in the absence of a confirmed infection. Detection of bacterial DNA has been investigated as a marker of SBP and as a predictor of prognosis. Data is, however, contradictory. Here we investigated whether levels of IL-6 and IL-8 putatively produced by myeloid cells in ascites are associated with systemic inflammation and whether inflammation depends on the presence of specific bacterial DNA. Methods and Materials: We enrolled 33 patients with decompensated liver cirrhosis from whom we collected paired samples of blood and ascites. IL-6 and IL-8 were measured in serum samples of all patients using ELISA. In a subset of 10 representative patients, bacterial DNA was extracted from ascites and whole blood, followed by 16S rRNA gene amplicon sequencing. Results: There were significantly higher levels of IL-6 in ascites fluid compared to blood samples in all patients. Interestingly, IL-6 levels in blood correlated tightly with disease severity and surrogates of systemic inflammation, while IL-6 levels in ascites did not. Moreover, patients with higher blood CRP levels showed greater SBP prevalence compared to patients with lower levels, despite similar positive culture results. Bacterial richness was also significantly higher in ascites compared to the corresponding patient blood. We identified differences in microbial composition and diversity between ascites and blood, but no tight relationship with surrogates of systemic inflammation could be observed. Discussion: In decompensated cirrhosis, markers of systemic inflammation and microbiota composition seem to be dysregulated in ascites and blood. While a relationship between systemic inflammation and microbiota composition seems to exist in blood, this is not the case for ascites in our hands. These data may suggest compartmentalization of the immune response and interaction of the latter with the microbiota especially in the blood compartment.

Combination of vial culture and broad-range PCR for the diagnosis of spontaneous bacterial peritonitis: experience in a Greek tertiary care hospital

Spontaneous bacterial peritonitis (SBP) is often difficult to diagnose because bacteria in ascites cannot be detected accurately by conventional culture. In this study, we evaluated the use of broad-range 16S rRNA PCR, applied either directly to a total of 32 ascitic fluids (AFs) or to the AF vial cultures, after a long incubation of 14 days; the results were compared with those of AF vial cultures. Escherichia coli was isolated in four of 32 AF vial cultures (12.5%). The application of 16S rRNA PCR directly to AF detected only one of the four positive samples (sensitivity 25%, specificity 100%, positive predictive value (PPV) 100%, negative predictive value (NPV) 90.32%). However, the application of 16S rRNA PCR to AF vial cultures after 14 days of incubation correctly identified all the positive samples, including one more that was positive for Brucella mellitensis (sensitivity 100%, specificity 80%, PPV 80%, NPV 100%). The elongation of the incubation period of the AF vial cultures, combined with the use of 16S rRNA in negative vials, increases the possibility of identifying the causative agents of SBP and could be applied in the clinical laboratory.

Bacterial translocation in patients with liver cirrhosis: physiology, clinical consequences, and practical implications

The gut liver axis is an operative unit that works to protect the human body against potentially harmful substances and microorganisms, maintaining the homeostasis of the immune system. Liver cirrhosis profoundly alters this complex system. The intestine becomes more permeable allowing the translocation of bacteria, bacterial products and fragments into the portal circulation, triggering an abnormal local and systemic inflammatory response and a condition of perpetual immunologic alarm. This immune-inflammatory disorder related to dysbiosis is involved in the development of liver damage and liver cirrhosis complications and increases intestinal permeability in a vicious circle. Areas covered: The most relevant studies on bacterial translocation, the mechanism of intestinal barrier dysfunction and its consequences in patients with liver cirrhosis have been revised through a PubMed search. Data have been discussed with particular regard to their significance in clinical practice. Expert commentary: The assessment of bacterial translocation and intestinal permeability is not currently used in clinical practice but may be useful to stratify patients' prognosis.

Bacterial translocation markers in liver cirrhosis

Bacterial translocation (BT) is an important mechanism in the development of infection in liver cirrhosis. The migration and colonization of bacteria and/or bacterial products from the bowel to mesenteric lymph nodes is a controlled process in healthy persons. Increased intestinal permeability, bacterial overgrowth and defect of gut-associated lymphatic tissue promote impaired BT in cirrhotics. We reviewed the reports on markers used for the evaluation of BT published between 1987 and 2016. We focused on the clinical consequences of BT in cirrhosis, as indicated by the values of the BT markers. Patients with cirrhosis are reported to have elevated levels of surrogate markers associated with BT compared with controls. The most widely used BT parameters are C-reactive protein, procalcitonin, bacterial DNA, endotoxin or lipopolysaccharide, lipopolysaccharide binding protein, calprotectin, and bactericidal/permeability increasing protein. High levels of these factors in serum and/or ascitic fluid in humans may be associated with advanced liver disease, hemodynamic instability, high levels of proinflammatory cytokines, susceptibility to the development of severe or recurrent infections, acute-on-chronic liver failure, hepatic encephalopathy, hepatorenal syndrome and poor prognosis during follow up. In conclusion, high levels of BT markers are associated with a high inflammatory response, increased complications of liver cirrhosis and occasionally high fatality rates.

Markers of bacterial translocation in end-stage liver disease

Bacterial translocation (BT) refers to the passage of viable bacteria or bacterial products from the intestinal lumen, through the intestinal epithelium, into the systemic circulation and extraintestinal locations. The three principal mechanisms that are thought to be involved in BT include bacterial overgrowth, disruption of the gut mucosal barrier and an impaired host defence. BT is commonly observed in liver cirrhosis and has been shown to play an important role in the pathogenesis of the complications of end stage liver disease, including infections as well as hepatic encephalopathy and hepatorenal syndrome. Due to the importance of BT in the natural history of cirrhosis, there is intense interest for the discovery of biomarkers of BT. To date, several such candidates have been proposed, which include bacterial DNA, soluble CD14, lipopolysaccharides endotoxin, lipopolysaccharide-binding protein, calprotectin and procalcitonin. Studies on the association of these markers with BT have demonstrated not only promising data but, oftentimes, contradictory results. As a consequence, currently, there is no optimal marker that may be used in clinical practice as a surrogate for the presence of BT.

Spontaneous bacterial peritonitis: The clinical challenge of a leaky gut and a cirrhotic liver

Spontaneous bacterial peritonitis (SBP) is a frequent, life-threatening bacterial infection in patients with liver cirrhosis and ascites. Portal hypertension leads to increased bacterial translocation from the intestine. Failure to eliminate invading pathogens due to immune defects associated with advanced liver disease on the background of genetic predisposition may result in SBP. The efficacy of antibiotic treatment and prophylaxis has declined due to the spread of multi-resistant bacteria. Patients with nosocomial SBP and with prior antibiotic treatment are at a particularly high risk for infection with resistant bacteria. Therefore, it is important to adapt empirical treatment to these risk factors and to the local resistance profile. Rifaximin, an oral, non-absorbable antibiotic, has been proposed to prevent SBP, but may be useful only in a subset of patients. Since novel antibiotic classes are lacking, we have to develop prophylactic strategies which do not induce bacterial resistance. Farnesoid X receptor agonists may be a candidate, but so far, clinical studies are not available. New diagnostic tests which can be carried out quickly at the patient’s site and provide additional prognostic information would be helpful. Furthermore, we need tools to predict antibiotic resistance in order to tailor first-line antibiotic treatment of spontaneous bacterial peritonitis to the individual patient and to reduce mortality.

Diagnosis and treatment of spontaneous bacterial peritonitis in cirrhotic patients

Spontaneous bacterial peritonitis (SBP) is a common complication in liver cirrhotic patients with ascites. Polymorphonuclear cells > 250/mL and bacterial cultures of ascitic fluid are main means for diagnosis of SBP. Leukocyte esterase isozyme, pH value, procalcitonin, lactoferrin, granulocyte elastase and phagocytized bacterial DNA in leukocytes from ascitic fluid also play a role in the diagnosis of SBP. Third-generation cephalosporins (especially cefotaxime) are the most appropriate antibiotics for the treatment of SBP. Albumin infusion can prevent renal impairment and reduce mortality among patients with SBP.

Multiplex PCR performed of bronchoalveolar lavage fluid increases pathogen identification rate in critically ill patients with pneumonia: a pilot study

Background

In critically ill patients with pneumonia, accurate microorganism identification allows appropriate antibiotic treatment. In patients undergoing bronchoalveolar lavage (BAL), direct examination of the fluid using Gram staining provides prompt information but pathogen identification accuracy is low. Culture of BAL fluid is actually the reference, but it is not available before 24 to 48 h. In addition, pathogen identification rate observed with direct examination and culture is decreased when antibiotic therapy has been given prior to sampling. We therefore assessed, in critically ill patients with suspected pneumonia, the performance of a multiplex PCR (MPCR) to identify pathogens in BAL fluid. This study is a prospective pilot observation.

Methods

We used a MPCR detecting 20 types of microorganisms. Direct examination, culture, and MPCR were performed on BAL fluid of critically ill patients with pneumonia suspicion. The final diagnosis of infective pneumonia was retained after the medical chart was reviewed by two experts. Pathogen identification rate of direct examination, culture, and MPCR in patients with confirmed pneumonia was compared.

Results

Among the 65 patients with pneumonia suspicion, the diagnosis of pneumonia was finally retained in 53 cases. Twenty nine (55%) were community-acquired pneumonia and 24 (45%) were hospital acquired. Pathogen identification rate with MPCR (66%) was greater than with culture (40%) and direct examination (23%) (p =0.01 and p <0.001, respectively). When considering only the microorganisms included in the MPCR panel, the pathogen identification rate provided by MPCR reached 82% and was still higher than with culture (35%, p <0.001) and direct examination (21%, p <0.001). Pathogen identification rate provided by MPCR was not modified in the case of previous antibiotic treatment (66% vs. 64%, NS) and was still better than with culture (23%, p <0.001).

Conclusions

The results of this pilot study suggest that in critically ill patients, MPCR performed on BAL fluid could provide higher identification rate of pathogens involved in pneumonia than direct examination and culture, especially in patients having received antimicrobial treatment.

Application of next-generation sequencing to study ascitic microbiome in cirrhotic patients with or without spontaneous bacterial peritonitis

BACKGROUND

Spontaneous bacterial peritonitis is an important cause of morbidity and mortality in cirrhotic patients with ascites. The key step in the pathogenesis of spontaneous bacterial peritonitis is bacterial translocation from intestinal lumen to mesenteric lymph nodes, and from there to the systemic circulation and ascitic fluid. We aimed to study the ascitic microbiota of cirrhotic patients with or without spontaneous bacterial peritonitis.

METHODS

Both the 16S polymerase chain reaction approach and the whole genome shotgun approach were adopted for the next-generation sequencing technology. We compared the results derived from the two methods.

RESULTS

The bacterial culture-negative ascites in cirrhotic patients, which even failed for amplification of 16S ribosomal DNA, were found to contain much less bacterial DNA than the culture-positive ones, indicating that the paucity of bacteria, instead of the difficulty of bacterial culture, was possibly the main reason for negative culture result of the ascites. Escherichia coli was the predominant species in all samples, and the bacteria of low abundance were also identified by the next-generation sequencing technology.

CONCLUSION

Whole genome shotgun-based next-generation sequencing is an appropriate method for depicting the microbiome of ascites or of other specimens with a low abundance of bacterial DNA.

Bacterial infections in cirrhosis: a position statement based on the EASL Special Conference 2013

Bacterial infections are very common and represent one of the most important reasons of progression of liver failure, development of liver-related complications, and mortality in patients with cirrhosis. In fact, bacterial infections may be a triggering factor for the occurrence of gastrointestinal bleeding, hypervolemic hyponatremia, hepatic encephalopathy, kidney failure, and development of acute-on-chronic liver failure. Moreover, infections are a very common cause of repeated hospitalizations, impaired health-related quality of life, and increased healthcare costs in cirrhosis. Bacterial infections develop as a consequence of immune dysfunction that occurs progressively during the course of cirrhosis. In a significant proportion of patients, infections are caused by gram-negative bacteria from intestinal origin, yet gram-positive bacteria are a frequent cause of infection, particularly in hospitalized patients. In recent years, infections caused by multidrug-resistant bacteria are becoming an important clinical problem in many countries. The reduction of the negative clinical impact of infections in patients with cirrhosis may be achieved by a combination of prophylactic measures, such as administration of antibiotics, to reduce the occurrence of infections in high-risk groups together with early identification and management of infection once it has developed. Investigation on the mechanisms of altered gut microflora, translocation of bacteria, and immune dysfunction may help develop more effective and safe methods of prevention compared to those that are currently available. Moreover, research on biomarkers of early infection may be useful in early diagnosis and treatment of infections. The current manuscript reports an in-depth review and a position statement on bacterial infections in cirrhosis.

Molecular diagnosis of sepsis: New aspects and recent developments

By shortening the time to pathogen identification and allowing for detection of organisms missed by blood culture, new molecular methods may provide clinical benefits for the management of patients with sepsis. While a number of reviews on the diagnosis of sepsis have recently been published we here present up-to-date new developments including multiplex PCR, mass spectrometry and array techniques. We focus on those techniques that are commercially available and for which clinical studies have been performed and published.

Application of qualitative and quantitative real-time PCR, direct sequencing, and terminal restriction fragment length polymorphism analysis for detection and identification of polymicrobial 16S rRNA genes in ascites

Qualitative and quantitative 16S rRNA gene-based real-time PCR and direct sequencing were applied for rapid detection and identification of bacterial DNA (bactDNA) in 356 ascites samples. bactDNA was detected in 35% of samples, with a mean of 3.24 log copies ml(-1). Direct sequencing of PCR products revealed 62% mixed chromatograms predominantly belonging to Gram-positive bacteria. Terminal restriction fragment length polymorphism (T-RFLP) results of a sample subset confirmed sequence data showing polymicrobial DNA contents in 67% of bactDNA-positive ascites samples.

Procalcitonin and macrophage inflammatory protein-1 beta (MIP-1β) in serum and peritoneal fluid of patients with decompensated cirrhosis and spontaneous bacterial peritonitis

PURPOSE

Spontaneous bacterial peritonitis (SBP) is the most frequent infection in patients with cirrhosis causing significant mortality which requires rapid recognition for effective antibiotic therapy, whereas ascitic fluid cultures are frequently negative. The aim of this study was to evaluate the SBP diagnostic efficacy of procalcitonin (PCT) and macrophage inflammatory protein-1 beta (MIP-1β) measured in serum and peritoneal fluid.

MATERIAL/METHODS

Thirty-two participants with liver cirrhosis and ascites were included into the study (11 females and 21 males, mean age 49.5 ± 11.9 years). The peritoneal fluid and venous blood were collected for routine laboratory examinations and measurements of PCT and MIP-1β. Patients were divided into two groups according to the ascitic absolute polymorphonuclear leukocytes count (≥250 mm(-3) and <250 mm(-3)).

RESULTS

Ascites was sterile in 22 participants and SBP was diagnosed in 10 patients. Serum and ascitic levels of PCT and MIP-1β did not correlate with clinical and routine laboratory parameters. MIP-1β in the ascitic fluid was significantly higher in patients with SBP (213 ± 279 pg/ml vs. 66.3 ± 49.8 pg/ml; p=0.01). The sensitivity and specificity for diagnosis of SBP with ascitic MIP-1β were 80% and 72.7%, respectively (cut-off value 69.4 pg/ml) with AUROC 0.77 (95%CI 0.58-0.96). Serum levels of MIP-1β showed lower diagnostic yield. Serum and ascitic PCT levels were not different in patients with and without SBP.

CONCLUSIONS

MIP-1β concentration in ascitic fluid may distinguish patients with and without SBP with satisfactory sensitivity and specificity. Chemokines should be further explored for diagnostic use.

Diagnostics, therapy and outcome prediction in abdominal sepsis: current standards and future perspectives

PURPOSE

In the perioperative phase, sepsis and sepsis-associated death are the most important problems for both the surgeon and the intensivist. Critically ill patients profit from an early identification and implementation of an interdisciplinary therapy. The purpose of this review on septic peritonitis is to give an update on the diagnosis and its evidence-based treatment.

RESULTS

Rapid diagnosis of sepsis is essential for patient´s survival. A bundle of studies was performed on early recognition and on new diagnostic tools for abdominal sepsis. Although surgical intervention is considered as an essential therapeutic step in sepsis therapy the time-point of source control is still controversially discussed in the literature. Furthermore, the Surviving Sepsis Campaign (SSC) guidelines were updated in 2012 to facilitate evidence-based medicine for septic patients.

CONCLUSION

Despite many efforts, the mortality of surgical septic patients remains unacceptably high. Permanent clinical education and further surgical trials are necessary to improve the outcome of critically ill patients.

No difference in portal and hepatic venous bacterial DNA in patients with cirrhosis undergoing transjugular intrahepatic portosystemic shunt insertion

BACKGROUND

Bacterial translocation (BT) with immune activation may lead to hemodynamical alterations and poor outcomes in patients with cirrhosis.

AIMS

We investigated bacterial DNA (bDNA), a marker of BT, and its relation to portal pressure and markers of inflammation in the portal and hepatic veins in patients with cirrhosis undergoing TIPS insertion.

METHODS

We analysed plasma for bDNA and markers of inflammation in 28 patients [median portal pressure gradient 15 (11-19) mmHg] during TIPS treatment for refractory ascites (n = 19) or acute variceal bleeding (n = 9). Advanced cirrhosis was present in the majority [Child-Pugh class (A/B/C): 1/14/13], and most often caused by alcohol (n = 21).

RESULTS

bDNA was detectable in one or both samples in 16 of 28 patients (57%). bDNA was present in 39% of the samples from the portal vein vs 43% of the samples in the hepatic vein (P = 0.126). Antibiotics had no effect on bDNA or markers of inflammation. Markers of inflammation did not differ between the hepatic and portal veins with the exceptions of soluble urokinase plasminogen activating receptor (suPAR) and vascular endothelial growth factor (VEGF), both higher in the hepatic vein (P = 0.031 and 0.003 respectively).

CONCLUSIONS

No transhepatic gradient of bDNA was evident, suggesting that no major hepatic elimination of bDNA occurs in advanced liver disease. bDNA, in contrast to previous reports was largely unrelated to a panel of markers of inflammation and without relation to portal pressure.

Leaky gut and the liver: A role for bacterial translocation in nonalcoholic steatohepatitis

Gut flora and bacterial translocation (BT) play important roles in the pathogenesis of chronic liver disease, including cirrhosis and its complications. Intestinal bacterial overgrowth and increased bacterial translocation of gut flora from the intestinal lumen predispose patients to bacterial infections, major complications and also play a role in the pathogenesis of chronic liver disorders. Levels of bacterial lipopolysaccharide, a component of gram-negative bacteria, are increased in the portal and/or systemic circulation in several types of chronic liver disease. Impaired gut epithelial integrity due to alterations in tight junction proteins may be the pathological mechanism underlying bacterial translocation. Preclinical and clinical studies over the last decade have suggested a role for BT in the pathogenesis of nonalcoholic steatohepatitis (NASH). Bacterial overgrowth, immune dysfunction, alteration of the luminal factors, and altered intestinal permeability are all involved in the pathogenesis of NASH and its complications. A better understanding of the cell-specific recognition and intracellular signaling events involved in sensing gut-derived microbes will help in the development of means to achieve an optimal balance in the gut-liver axis and ameliorate liver diseases. These may suggest new targets for potential therapeutic interventions for the treatment of NASH. Here, we review some of the mechanisms connecting BT and NASH and potential therapeutic developments.

Identification of bacterial pathogens in ascitic fluids from patients with suspected spontaneous bacterial peritonitis by use of broad-range PCR (16S PCR) coupled with high-resolution melt analysis

Spontaneous bacterial peritonitis (SBP) can be a severe complication occurring in patients with cirrhosis and ascites, with associated mortality often as high as 40%. Traditional diagnostics for SBP rely on culture techniques for proper diagnosis, although recent reports suggest that the presence of bacterial DNA in peritoneal fluid in patients with cirrhosis and ascites is an indicator of SBP. A previously published broad-range PCR (16S PCR) coupled with high-resolution melt analysis (HRMA) was compared with standard culture techniques for diagnosis of SBP in 106 peritoneal fluid samples from patients with suspected SBP. The sensitivity and specificity for 16S PCR for detecting eubacterial DNA compared with those of standard culture techniques were 100% (17/17) and 91.5% (85/89), respectively. Overall, HRMA concordance with species identification was 70.6% (12/17), although the 5 samples that were discordant at the species level were SBP resulting from a polymicrobial infection, and species-level identification for polymicrobial infections is outside the capability of HRMA. Both the broad-range 16S PCR and HRMA analysis provide useful diagnostic adjunctive assays for clinicians in detecting and identifying pathogens responsible for SBP.

Toll-like receptor (TLR) 2 promoter and intron 2 polymorphisms are associated with increased risk for spontaneous bacterial peritonitis in liver cirrhosis

BACKGROUND & AIMS

Toll-like receptor (TLR) 2 and nucleotide-binding oligomerisation domain (NOD) 2 recognize distinct pathogen-associated molecular patterns (PAMS) on the cell surface and in the cytoplasm, respectively. Since they may contribute to susceptibility to spontaneous bacterial peritonitis (SBP), we studied the effects of TLR2 gene variants on susceptibility for SBP in relation to the previously reported NOD2 alleles.

METHODS

Overall, 150 patients with liver cirrhosis and ascites were genotyped for TLR2 gene variants -16934 (rs4696480), Arg753Gln (rs5743708), Pro631His (rs5743704) and the TLR2 GT microsatellite polymorphism in intron 2. Patients were monitored for SBP over two years. TLR2 SNPs were identified by hybridization probe assays on a LightCycler system. Numbers of GT repeats were determined with an ABI310 sequencer and Genescan Analysis 2.1 software.

RESULTS

Fifty two patients (35%) had SBP. Unlike the TLR2 Arg753Gln and Pro631His mutations, SBP was significantly more frequent in patients with the TLR2 -16934 TT genotype (38.5% vs. 15.3%; p = 0.002) and in carriers with two long tandem GT repeat alleles (>20) (53.8% vs. 25.5%; p = 0.001). A multivariate analysis confirmed TLR2 GT microsatellite polymorphism (OR = 3.8, p = 0.002) and NOD2 variants (OR = 3.3, p = 0.011) as independent predictors of SBP, and the simultaneous presence of both risk factors indicated a particularly high risk for SBP (OR = 11.3, p = 0.00002).

CONCLUSIONS

Analogous to NOD2 risk variants, TLR2 polymorphisms indicate increased susceptibility toward SBP in cirrhotic patients with ascites, and the combination of the TLR2 GT microsatellite polymorphism with at least one NOD2 risk variant enables improved identification of patients with a high risk for SBP.

Homozygous carrier of the NOD2 1007fs frame-shift mutation presenting with refractory community-acquired spontaneous bacterial peritonitis and developing fatal pulmonary mucormycosis: A case report

Genetic variants of the innate immune system contribute to episodes of spontaneous bacterial peritonitis (SBP) in patients with cirrhosis. We herein report the case of a patient with the homozygous nucleotide-binding oligomerization domain containing 2 (NOD2) frame-shift mutation 1007fs presenting with sepsis and community-acquired SBP by Escherichia coli. Secondary peritonitis, pancreatic ascites and malignant causes were excluded by extensive diagnostic work-up. First-line treatment with ceftriaxone was not successful despite in vitro sensitivity of the isolated strain. Despite prolonged second-line treatment with imipenem/cilastatin and intermittent ascites drainage, the ascitic fluid neutrophil count remained markedly elevated in this patient. In the course of the disease the patient developed pneumonia with identification of the typical hyphae of mucormycosis in the bronchoalveolar lavage and died of sepsis with multi-organ failure. On the basis of this observation, variants of the innate immunity have to be considered in therapy-refractory SBP, even when they are community-acquired and caused by cephalosporin-sensitive Enterobacteriaceae.