Changes in blood biomarkers in Arabian horses with Clostridium difficile-induced enterocolitis.

Clostridium difficile (CD) is considered a major health care problem both in developing and developed countries; frequently reported to be associated with enterocolitis and diarrhea in horses and other animals. In this study, we examined acute phase response (APR), cytokines response, neopterin (NP) procalcitonin (PCT) production and oxidative stress condition in horses and foals with C. difficile-induced enterocolitis (CDIE) and evaluated the effectiveness of these parameters as biomarkers for the disease. A total of 407 Arabian horses in 35 stables were examined between January 2017 to December 2018. Only 24 out of 407 horses showed two or more signs of CDIE. The blood level of serum amyloid A (SAA), haptoglobin (HP), proinflammatory cytokines (TNF-α, IL-6 and IL1-ß), serum malondialdehyde (MDA), PCT and NPT in horses with CDIE were higher than in healthy horses. Nevertheless, the levels of nitric oxide (NO), superoxide dismutase (SOD) and total antioxidant concentration (TAC) were considerably lower in diseased horses compared to those that were healthy. The ROC curves for eleven selected blood parameters, both in healthy horses and horses with CDIE demonstrated that all examined blood markers had significant levels of differentiation between CDIE cases and healthy controls (AUC > 87.5). The data in this study suggest that the evaluation of acute-phase proteins, cytokines, PCT, NPT, and oxidative stress biomarkers may well be used as a tool for diagnosis and assessment of CDIE and in disease pathogenesis in Arabian horses.

MicroRNA-320a Monitors Intestinal Disease Activity in Patients With Inflammatory Bowel Disease.

OBJECTIVES: In patients with inflammatory bowel disease (IBD), a treat-to-target treatment strategy requires tight monitoring of disease activity. Noninvasive biomarkers may help to monitor the intestinal disease activity. We demonstrated recently that peripheral microRNA (miR)-320a expression in mice follows the course of experimental colitis. The aim of this study was to evaluate the potential of miR-320a to monitor the disease activity in patients with IBD, to predict the course of disease, and to distinguish IBD from infectious colitis. METHODS: The miR-320a levels were prospectively assessed by quantitative real-time polymerase chain reaction analysis of peripheral blood samples from 40 patients with Crohn's disease (CD) and 37 patients with ulcerative colitis (UC) as well as from 19 healthy control individuals and 7 patients with infectious colitis. Disease activity was quantified by appropriate clinical disease indices and endoscopic scoring systems. RESULTS: When compared with healthy controls, miR-320a blood levels were significantly increased in patients with active CD and UC (16.1 ± 2.6 vs 2,573 ± 941; vs 434 ± 96; both P < 0.001) and patients with IBD in remission (316 ± 251 [CD] and 91 ± 29 [UC]; both P < 0.001). In patients with CD, miR-320a levels showed a strong correlation with the endoscopic disease activity (r = 0.76; P < 0.001). Similarly, in patients with UC, we detected a significantly enhanced miR-320a expression, which was highest in patients with severe endoscopic disease activity (eMayo = 0-1: 66 ± 16 vs eMayo = 2: 352 ± 102; vs eMayo = 3: 577 ± 206; both P < 0.001). Finally, miR-320a blood expression in patients with active CD and UC significantly increased compared with patients with infectious colitis (63 ± 13, P < 0.001). DISCUSSION: MiR-320a expression in peripheral blood from patients with IBD follows the clinical and endoscopic disease activities and may help to distinguish IBD from infectious colitis.

Relationship between faecal metronidazole and lactoferrin concentrations to clinical response of patients with Clostridioides difficile.

OBJECTIVES: We investigated patients with Clostridioides difficile-associated diarrhoea to see if clinical resolution correlated with faecal concentrations of metronidazole or markers of inflammation. METHODS: Faecal metronidazole, lactoferrin and serum CRP were measured daily. These were then compared with clinical progress. RESULTS: Metronidazole concentration correlated with lactoferrin (ρ = 0.17, p = 0.015), CRP (ρ = 0.23, p < 0.001) and number of diarrhoeal stools per day (ρ = 0.29, p < 0.001). Lactoferrin correlated with CRP (ρ = 0.57, p < 0.001) and the number of diarrhoeal stools per day (ρ = 0.52, p < 0.001) as did CRP (ρ = 0.52, p < 0.001). CONCLUSIONS: We found no association between cessation of diarrhoea and metronidazole or lactoferrin concentrations. There was a relationship between metronidazole concentrations and markers of inflammation and stool frequency.

Thrombin generation is increased in patients with Clostridium difficile colitis - a pilot study.

Background: There are only limited data in the literature on the thrombotic risk of patients with Clostridium difficile (CD) colitis, although this disease is widespread throughout the world. Objective: The aim of this study was to explore thrombin generation in these patients - the best way to evaluate their coagulation. Methods: A prospective observational study was conducted during 15 months on hospitalized patients with CD colitis. Thrombin generation was performed in platelet-poor plasma using a Ceveron® alpha analyzer and was compared with a group of volunteer control subjects. Results: Thirty-three patients and 51 control subjects were enrolled in the study. Two biomarkers - mean velocity index and peak thrombin - were significantly higher in patient group, compared to the control subjects (p = 0.010, respectively, p = 0.0395). This pattern of thrombin generation suggests that patients with CD colitis without septic shock have a potential thrombotic risk. The mean velocity index significantly correlated with the estimated related risk of death according to the Charlson age-comorbidity index. Conclusions: The higher values of thrombin generation suggest that CD colitis increases the thromboembolic risk. The pattern of thrombin generation could identify patients with particularly higher thromboembolic risk. They are potential candidates for thromboprophylaxis strategies and monitorization.

Clostridium difficile flagellin FliC: Evaluation as adjuvant and use in a mucosal vaccine against Clostridium difficile.

The immunogenicity of bacterial flagellin has been reported in different studies. By its close interaction with the immune system, the flagellin represents an interesting adjuvant and vaccine candidate. Salmonella Typhimurium flagellin has already been tested as adjuvant to stimulate mucosal immunity. Here, we assessed the ability of Clostridium difficile flagellin FliC to act as a mucosal adjuvant, first combined with ovalbumin as antigen and second with a C. difficile surface protein, the precursor of the S-layer proteins SlpA. Using ovalbumin as antigen, we compared the gut mucosal adjuvanticity of FliC to Salmonella Typhimurium flagellin and cholera toxin. Two routes of immunization were tested in a mouse model: intra-rectal and intra-peritoneal, following which, gut mucosal and systemic antibody responses against ovalbumin (Immunoglobulins G and Immunoglobulins A) were analyzed by Enzyme-Linked Immuno Assay in intestinal contents and in sera. In addition, ovalbumin-specific immunoglobulin producing cells were detected in the intestinal lamina propria by Enzyme-Linked Immunospot. Results showed that FliC as adjuvant for immunization targeting ovalbumin was able to stimulate a gut mucosal and systemic antibody response independently of the immunization route. In order to develop a mucosal vaccine to prevent C. difficile intestinal colonization, we assessed in a mouse model the efficacy of FliC as adjuvant compared with cholera toxin co-administrated with the C. difficile S-layer precursor SlpA as antigen. After challenge, a significant decrease of C. difficile intestinal colonization was observed in immunized groups compared to the control group. Our results showed that C. difficile FliC could be used as adjuvant in mucosal vaccination strategy against C. difficile infections.

Clostridium difficile-Associated Colitis Post-Transplant Is Not Associated with Elevation of Tacrolimus Concentrations.

BACKGROUND: Diarrhea is a common condition after solid organ transplant (SOT); Clostridium difficile-associated colitis (CDAC) is one of the most common infections after SOT. We documented previously that some types of enteritis are associated with an elevation of tacrolimus (TAC) trough concentrations by interfering with the drug's complex metabolism. PATIENTS AND METHODS: Tacrolimus concentrations of 25 SOT recipients including 12 renal and 13 liver recipients before, during, and after CDAC were analyzed retrospectively. RESULTS: Median age of the 25 patients was 54 y (range, 36-71), there were 15 males and 10 females. Clostridium difficile-associated colitis developed at a median of 55 d (range 2-4551) post-SOT. Median TAC concentrations prior to the outbreak of CDAC were 6.9 ng/mL (range, <1.5-17.2), 5.6 ng/mL (range, <1.5-13.2) during diarrhea, and 7.4 ng/mL (range, <1.5-24.3) after resolution of diarrhea (p > 0.05, NS). Treatment of CDAC consisted of metronidazole for 14 d in all cases. All patients recovered from CDAC but seven patients had CDAC relapse. CONCLUSIONS: In contrast to other types of infectious diarrhea such as rotavirus enteritis and cryptosporidiosis, CDAC is not associated with an increase in TAC concentrations. This is because C. difficile causes primarily colitis as opposed to other organisms, which are associated with enteritis.

Can Procalcitonin Contribute to the Diagnosis of Clostridium difficile Colitis?

BACKGROUND: It is a challenge to diagnosis Clostridium difficile colitis. OBJECTIVES: To determine, among patients who developed nosocomial diarrhea, whether serum procalcitonin (PCT) can distinguish between C. difficile toxin (CDT)-positive and CDT-negative patients. METHODS: This prospective study included 50 adults (>18 years) who developed diarrhea during hospitalization, 25 with a positive fecal test for CDT (study group) and 25 CDT negative (control group). RESULTS: Baseline demographic and underlying illnesses were similar in both groups. Duration of diarrhea was 6 ± 4 days and 3 ± 1 in the study and control groups, respectively (P = 0.001). Mean blood count was 20 ± 15 and 9.9 ± 4, respectively (P = 0.04). CRP level was higher in the study than in the control group (10.9 ± 7.4 and 6.6 ± 4.8, P = 0.028). PCT level was higher in the study group (4.4 ± 4.9) than the control group (0.3 ± 0.5, P = 0.102). A PCT level > 2 ng/ml was found in 7/25 patients (28%) and 1/25 (4%), respectively [odds ratio 9.33, 95% confidence interval (0.98 to 220), P = 0.049]. Multivariate analysis showed that only duration of diarrhea and left shift of peripheral leucocytes were significant indicators of CDT (P = 0.014 and P = 0.019, respectively). The mortality rate was 12/25 (48%) vs. 5/25 (20%), respectively (P = 0.04). CONCLUSIONS: We found a non-significant tendency to higher PCT levels in patients with CDT-positive vs. CDT-negative nosocomial diarrhea. However, a PCT level > 2 ng/ml may help distinguish between these patients.

Chemokine CXCL13 expression was up-regulated in Clostridium difficile infection.

Clostridium difficile infection (CDI) is the leading cause of antibiotic- and healthcare-associated diarrhea. CXCL13 is a well-known CXC chemokine involved in inflammation, but its role in CDI remains unknown. In this study, serum and fecal samplings were collected from 51 CDI patients, 50 diarrhea patients without CDI and 50 healthy control subjects to determine the CXCL13 levels by enzyme-linked immunosorbent assay (ELISA). Besides, a mouse model of C. difficile infection was established, and murine serum and colon tissues were collected for detection of CXCL13 expression using quantitative real-time RT-PCR, ELISA, Western blot, or immunohistochemistry. We found that CXCL13 concentration in serum and fecal samples from CDI patients was significantly higher compared with that from diarrhea patients without CDI and that from healthy controls. Elevated serum CXCL13 positively and significantly correlated with blood markers of inflammation and yielded an increased area under the ROC curve of 0.929. In murine C. difficile infection, CXCL13 were also dramatically increased in serum and infected colon tissues at the transcriptional and protein levels. The elevated CXCL13 levels positively and significantly correlated with inflammatory scores. Therefore, CDI is associated with enhanced release of CXCL13. This study indicated that CXCL13 may be pathogenically involved in CDI and served as a potential new biomarker for diagnosis and prognosis in CDI.

Evaluation of gastrointestinal leakage using serum (1→3)-ß-D-glucan in a Clostridium difficile murine model.

Gastrointestinal (GI) leakage in Clostridium difficile-associated diarrhea (CDAD) is well known but is not routinely assessed in clinical practice. Serum (1→3)-ß-D-glucan (BG), a fungal cell wall component used as a biomarker for invasive fungal disease, was tested in a CDAD mouse model with and without probiotics. Higher serum fluorescein isothiocyanate-dextran (FITC-dextran) and spontaneous gram-negative bacteremia, GI leakage indicators, were frequently found in CDAD mice, which died compared with those which survived. BG, serum macrophage inflammatory protein-2 and FITC-dextran but not quantitative blood bacterial count differentiated the clinical severity. Interestingly, a specific dose of Lactobacillus rhamnosus L34 attenuated CDAD and decreased serum BG and FITC-dextran, but not other parameters. BG also showed a higher area under the receiver operating characteristic curve for 7-day mortality than FITC-dextran. Fifty-five percent of CDAD mice with BG ≥ 60 pg/ml (the human negative cut-off value for invasive fungal disease) at 1 day after C. difficile gavage died within 7 days. In conclusion, S: erum BG was elevated in mice with severe CDAD, an established model of GI leakage with a strong association with mortality rate. BG monitoring in patients with CDAD is of interest as both a potential prognostic tool and a therapeutic efficacy indicator.

Induction of antitoxin responses in Clostridium-difficile-infected patients compared to healthy blood donors.

According to the literature Clostridium difficile antitoxins are present in up to 66% of humans. In a survey of ∼400 plasma samples from healthy blood donors we found that less than 6% were positive for anti-TcdA or anti-TcdB antitoxins. Using the same standard immunoassay protocol, we looked for IgG and IgA antitoxins in the blood and stool samples from 25 patients with C. difficile infection (CDI). Some patients with CDI had no antitoxin detected at all, while others had high levels of specific IgG- and IgA-antitoxins against both TcdA and TcdB in blood and IgA-anti-TcdA and -anti-TcdB antibodies in stool. Systemic responses to TcdB and mucosal responses to TcdA predominated. Among patients infected with the NAP1/027/BI strain, systemic IgG-anti-TcdB responses were particularly elevated. In contrast, patients infected with non-027 strains had more elevated mucosal IgA-anti-TcdA responses. Furthermore, high titer sera did not correlate with high neutralizing potential. We hypothesize that paradoxical killing of primed B-cells by antibody-mediated endosomal uptake of the Large Clostridial Toxins, TcdA and TcdB leads to clonal elimination of the fittest B-cells. If this hypothesis is confirmed, immune suppression rather than protective humoral immunity might be the consequence in some patients infected with toxigenic C. difficile.

Multivalent display of minimal Clostridium difficile glycan epitopes mimics antigenic properties of larger glycans.

Synthetic cell-surface glycans are promising vaccine candidates against Clostridium difficile. The complexity of large, highly antigenic and immunogenic glycans is a synthetic challenge. Less complex antigens providing similar immune responses are desirable for vaccine development. Based on molecular-level glycan-antibody interaction analyses, we here demonstrate that the C. difficile surface polysaccharide-I (PS-I) can be resembled by multivalent display of minimal disaccharide epitopes on a synthetic scaffold that does not participate in binding. We show that antibody avidity as a measure of antigenicity increases by about five orders of magnitude when disaccharides are compared with constructs containing five disaccharides. The synthetic, pentavalent vaccine candidate containing a peptide T-cell epitope elicits weak but highly specific antibody responses to larger PS-I glycans in mice. This study highlights the potential of multivalently displaying small oligosaccharides to achieve antigenicity characteristic of larger glycans. The approach may result in more cost-efficient carbohydrate vaccines with reduced synthetic effort.

Identification of toxemia in patients with Clostridium difficile infection.

Toxemia can develop in Clostridium difficile-infected animals, and correlates with severe and fulminant disease outcomes. Circumstantial evidence suggests that toxemia may occur in patients with C. difficile infection (CDI), but positive diagnosis is extremely rare. We analyzed the potential for C. difficile toxemia in patients, determined its characteristics, and assessed challenges. C. difficile toxins in serum from patients were tested using an ultrasensitive cell-based assay and further confirmed by Rac1 glucosylation assay. The factors that hinder a diagnosis of toxemia were assessed, including investigation of toxin stability, the level of toxins-specific neutralizing antibodies in sera and its effect on diagnosis limits. CDI patients develop detectable toxemia in some cases (2.3%). Toxins were relatively stable in stored sera. Neutralizing anti-toxin antibodies were present during infection and positively correlated with the diagnosis limits. Thus, the masking effect of toxin-specific neutralizing antibodies is the major obstacle in diagnosing C. difficile toxemia using cell-based bioassays.

Risk factors, outcomes and epidemiology associated with Clostridium difficile infection in patients with haematological malignancies in a tertiary care hospital in China.

The purpose of this study was to evaluate the risk factors, outcomes and epidemiology associated with Clostridium difficile infection (CDI) in patients with haematological malignancies in a tertiary care hospital in China. C. difficile screening was performed on patients admitted for chemotherapy or haematopoietic stem cell transplantation between 2009 and 2013. C. difficile isolates were analysed by multilocus sequence typing, and a retrospective chart review was performed on all patients with a positive toxin assay. CDI was diagnosed in 21 haematology-oncology ward patients and 14 marrow transplantation service patients for a cumulative incidence of 1.89/1000 and 3.69/1000 patient-days, respectively. Univariate analyses showed that patients who received etoposide had an increased risk of CDI (odds ratio 4.25, 95 % confidence interval 1.32-13.64). There was only one patient death, for which CDI was not the primary cause. Ten sequence types (STs) were identified, of which ST-3 and ST-54 were the most common; the hypervirulent ST-1 (ribotype 027) and ST-11 (ribotype 078) C. difficile strains were not detected in the patients in this study. The incidence of CDI did not differ between patients receiving chemotherapy and those receiving haematopoietic stem cell transplantation. The only risk factor for chemotherapy patients was treatment with etoposide.

Clostridium difficile the hospital plague.

Clostridium difficile infection (CDI) has become one of the major public health threats in the last two decades. An increase has been observed not only in the rate of CDI, but also in its severity and mortality. Symptoms caused by this pathogen are accompanied by intense local and systemic inflammation. We confirmed that Raman microspectroscopy can help us in understanding CDI pathogenesis. A single erythrocyte of patients with CDI shows a difference, approximately 10 times, in the intensity of the Raman spectra at the beginning of hospitalization and after one week of treatment. The intensity level is an indicator of the spread of the inflammation within the cell, confirmed by standard laboratory tests. Many of the observed bands with enormously enhanced intensity, e.g. 1587, 1344, 1253, 1118 and 664 cm(-1), come from the symmetric vibration of the pyrrole ring. Heme variation of recovered cells in the acute CDI state between the first and the seventh day of treatment seems to show increased levels of oxygenated hemoglobin. Intense inflammation alters the conformation of the protein which is reflected in the significant changes in the amide I, II and III bands. There is an observed shift and a significant intensity increase of 1253 and 970 cm(-1) amide III and skeletal protein backbone CC stretching vibration bands, respectively. Principal Component Analysis (PCA) was used to find the variance in the data collected on the first and seventh day. PC2 loading in the 1645-1500 cm(-1) range shows an increase of heme, Tyr, Trp, or Phe vibrations because of changes in the protein microenvironment due to their exposure. Positive maxima at 1621, 1563 and 1550 in the PC2 loading originated from the ring vibrations. These observations indicate that Clostridium difficile toxins induce cytopathogenicity by altering cellular proteins.

Rheological properties of erythrocytes in patients infected with Clostridium difficile.

INTRODUCTION: Clostridium difficile infection (CDI) is a bacterial infection of the digestive tract. Acute infections are accompanied by increased risk for venous thromboembolism (VTE). To date, there have been no studies of the rheological properties of blood during the course of digestive tract infections. The aim of our study was to examine the effects of CDI on red blood cell (RBC) rheology, specifically RBC deformability, RBC aggregation, and plasma viscosity. In addition, the activity of glucose 6 phosphate dehydrogenase (G6PD) and acetylcholinesterase (AChE) in RBC was studied. MATERIALS AND METHODS: Our study group included 20 patients with CDI, 20 healthy persons comprised the control group. We examined the effects of CDI on the rheology of RBCs, their deformability and aggregation, using a Laser-assisted Optical Rotational Cell Analyzer (LORCA). Plasma viscosity was determined using a capillary tube plasma viscosymeter. Moreover, we estimated the activity of AChE and G6PD in RBC using spectrophotometric method. RESULTS: A statistically significant increase was found in the aggregation index, viscosity and activity of G6PD whereas the amount of time to reach half of maximum aggregation (t½) and the amplitude of aggregation (AMP) both showed statistically significantly decreases among patients with CDI compared to the control group. We also observed that the Elongation Index (EI) was decreased when shear stress values were low, between 0.3 Pa and 0.58 Pa, whereas EI was increased for shear stress in the range of 1.13-59.97 Pa. These observations were statistically significant. CONCLUSIONS: We report for the first time that acute infection of the gastrointestinal tract with Clostridium difficile is associated with abnormalities in rheological properties of blood, increased serum viscosity as well as increased aggregation of RBCs, which correlated with severity of inflammation. These abnormalities may be an additional mechanism causing increased incidence of VTE in CDI.

Vitamin D deficiency is associated with community-acquired clostridium difficile infection: a case-control study.

BACKGROUND: Clostridium difficile infection (CDI) is increasingly recognized as an important community acquired pathogen causing disease (CA-CDI). Vitamin D [25(OH)D] has immune modulatory effects and plays an important role in intestinal immunity. The role of vitamin D in CA-CDI has not been examined previously. METHODS: This was a single referral center case-control study. Cases comprised of all patients with CA-CDI who had a serum 25(OH)D measured within 12 months prior to infection. Controls were drawn from patients who had 25(OH)D checked and matched based on age, gender, race and health status. Serum 25(OH)D was stratified as < 15 ng/mL, 15-30 ng/mL or > 30 ng/mL. Regression models adjusting for potential confounders were used to define independent association between vitamin D and CA-CDI. RESULTS: We identified 58 matched case-control pairs (66% women; 85% Caucasian). The mean age was 62 years. The mean serum 25(OH)D level was significantly lower in CA-CDI cases compared to controls (28.5 ng/mL vs. 33.8 ng/mL, p = 0.046). Cases had higher rate of antibiotic exposure and more comorbidity. Serum 25(OH)D < 15 ng/mL was associated with an increased risk of CA-CDI on univariate (Odds ratio (OR) 5.10, 95% confidence interval (CI) 1.51 - 17.24) and multivariate analysis (OR 3.84, 95% CI 1.10 - 13.42). Vitamin D levels between 15-30 ng/mL did not modify disease risk. CONCLUSIONS: Low serum 25(OH)D < 15 ng/mL was associated with increased risk of CA-CDI. This suggests vitamin D may have a role in determining susceptibility to CA-CDI.

The role of local and systemic cytokines in patients infected with Clostridium difficile.

It is widely accepted that the pathogenesis of Clostridium difficile infection (CDI) is multifactorial, dependent on pathogen virulence factors produced by the organism as well as disorders of the gastrointestinal tract, the alteration in intestinal flora and the immune response of the host. In particular, the immune response in the course of CDI and the involvement of cytokines in the pathogenesis of CDI is not fully understood. The aim of our study was to evaluate the relationship between proinflammatory and anti-inflammatory cytokines and the course of CDI in vivo. We prospectively studied 80 patients. Our study group included 40 patients aged 30-87 years (mean age 66.9 years) with CDI hospitalized at Infectious Diseases Department and Gastroenterology and Hepatology Clinic, University Hospital in Cracow, and 40 healthy volunteers aged 24-62 years (mean age 51.1 years). The serum concentrations of cytokines IL-1ß, IL-6, IL-8, IL-10, tumor necrosis factor (TNF-α), myeloperoxidase (MPO), and prostaglandin E2 (PGE2) were measured using ELISA assays. Additionally, the routine biochemical parameters were assessed including the following: white blood cells with differential leukocyte count, platelets counts, and blood plasma levels of creatinine, alanine transaminase, and C-reactive protein were determined. We noted a significant increase in the concentration of the following cytokines in the CDI group when compared to the control group: IL-1b (4.7 vs. 3.6 pg/ml), IL-6 (21.0 vs. 0.04 pg/ml), IL-10 (8.5 vs. 0.5 pg/ml), TNF-α (7.1 vs. 0.09 pg/ml). In addition the serum concentration of MPO (1056.0 vs. 498.0 pg/ml), and PGE2 (2036.7 vs. 1492.0 pg/ml) showed a significant increase in CDI patients as compared with control subjects. Most CDI patients did not show any increase in the concentration of IL-8. We did observe a direct relationship between TNF-α and creatinine. The course of CDI is characterized by an initial local inflammatory process followed by a systemic inflammatory response, which manifests clinically as fever, and includes leukocytosis, an increase in the level of neutrophils in the blood, and an increase in the serum concentrations of TNF-α, IL-1ß, IL-6, IL-10, MPO and PGE2. Despite the leading role of IL-8 in the local inflammatory process, we postulate TNF-α and IL-6 play a key role in the systemic inflammatory response in CDI, and the plasma TNF-α level seems to act as a major factor of poor prognosis in patients with CDI.

Serum mannose-binding lectin concentration, but not genotype, is associated with Clostridium difficile infection recurrence: a prospective cohort study.

BACKGROUND: Mannose-binding lectin (MBL) plays a key role in the activation of the lectin-complement pathway of innate immunity, and its deficiency has been linked with several acute infections. However, its role in predisposing to, or modulating disease severity in, Clostridium difficile infection (CDI) has not been investigated. METHODS: We prospectively recruited 308 CDI case patients and 145 control patients with antibiotic-associated diarrhea (AAD). CDI outcome measures were disease severity, duration of symptoms, 30-day mortality, and 90-day recurrence. Serum concentrations of MBL were determined using a commercial enzyme-linked immunosorbent assay transferred to an electrochemiluminescence-based platform. MBL2 polymorphisms were typed using a combination of pyrosequencing and TaqMan genotyping assays. RESULTS: The frequency of the MBL2 genetic variants was similar to that reported in other white populations. MBL serum concentrations in CDI and AAD subjects were determined by MBL2 exonic variants B, C, and D and the haplotypes (LYPB, LYQC, and HYPD). There was no difference in either MBL concentrations or genotypes between cases and controls. MBL concentration, but not genotype, was a determinant of CDI recurrence (odds ratios, 3.18 [95% confidence interval {CI}, 1.40-7.24] and 2.61 [95% CI, 1.35-5.04] at the <50 ng/mL and <100 ng/mL cutoff points, respectively; P < .001). However, neither MBL concentration nor MBL2 genotype was linked with the other CDI outcomes. CONCLUSIONS: Serum MBL concentration did not differentiate between CDI cases and AAD controls, but among CDI cases, MBL concentration, but not genotype, was associated with CDI recurrence, indicating that MBL acts as a modulator of disease, rather than a predisposing factor.

Predictors of Clostridium difficile infection severity in patients hospitalised in medical intensive care.

AIM: To describe and analyse factors associated with Clostridium difficile infection (CDI) severity in hospitalised medical intensive care unit patients. METHODS: We performed a retrospective cohort study of 40 patients with CDI in a medical intensive care unit (MICU) at a French university hospital. We include patients hospitalised between January 1, 2007 and December 31, 2011. Data on demographics characteristics, past medical history, CDI description was collected. Exposure to risk factors associated with CDI within 8 wk before CDI was recorded, including previous hospitalisation, nursing home residency, antibiotics, antisecretory drugs, and surgical procedures. RESULTS: All included cases had their first episode of CDI. The mean incidence rate was 12.94 cases/1000 admitted patients, and 14.93, 8.52, 13.24, 19.70, and 8.31 respectively per 1000 admitted patients annually from 2007 to 2011. Median age was 62.9 [interquartile range (IQR) 55.4-72.40] years, and 13 (32.5%) were women. Median length of MICU stay was 14.0 d (IQR 5.0-22.8). In addition to diarrhoea, the clinical symptoms of CDI were fever (> 38 °C) in 23 patients, abdominal pain in 15 patients, and ileus in 1 patient. The duration of diarrhoea was 13.0 (8.0-19.5) d. In addition to diarrhoea, the clinical symptoms of CDI were fever (> 38 °C) in 23 patients, abdominal pain in 15 patients, and ileus in 1 patient. Prior to CDI, 38 patients (95.0%) were exposed to antibiotics, and 12 (30%) received at least 4 antibiotics. Fluoroquinolones, 3(rd) generation cephalosporins, coamoxiclav and tazocillin were prescribed most frequently (65%, 55%, 40% and 37.5%, respectively). The majority of cases were hospital-acquired (n = 36, 90%), with 5 cases (13.9%) being MICU-acquired. Fifteen patients had severe CDI. The crude mortality rate within 30 d after diagnosis was 40% (n = 16), with 9 deaths (9 over 16; 56.3%) related to CDI. Of our 40 patients, 15 (37.5%) had severe CDI. Multivariate logistic regression showed that male gender [odds ratio (OR): 8.45; 95%CI: 1.06-67.16, P = 0.044], rising serum C-reactive protein levels (OR = 1.11; 95%CI: 1.02-1.21, P = 0.021), and previous exposure to fluoroquinolones (OR = 9.29; 95%CI: 1.16-74.284, P = 0.036) were independently associated with severe CDI. CONCLUSION: We report predictors of severe CDI not dependent on time of assessment. Such factors could help in the development of a quantitative score in ICU's patients.