James H. Boone

Fecal Lactoferrin is a sensitive and specific marker in identifying intestinal inflammation

OBJECTIVE:Lactoferrin is a glycoprotein expressed by activated neutrophils. The aim of this study was to determine the sensitivity and specificity of fecal lactoferrin concentrations for inflammatory bowel disease (IBD) or irritable bowel syndrome (IBS) versus healthy controls.METHODS:Fresh stool samples were collected from outpatients with ulcerative colitis (UC), Crohns disease (CD), or IBS. Clinical disease activity for IBD was assessed using a modified Harvey–Bradshaw Activity Index. Fecal lactoferrin concentrations were determined using a polyclonal antibody-based enzyme linked immunoassay. Mean fecal lactoferrin concentrations for each group and sensitivity and specificity of the assay were determined.RESULTS:One hundred-four CD patients, 80 UC patients, 31 IBS patients, and 56 healthy controls were recruited. The mean ± SE fecal lactoferrin concentration (μg/g fecal weight) was 440 ± 128 for CD patients, 1125 ± 498 for UC patients, 1.27 ± 0.29 for IBS patients, and 1.45 ± 0.4 for healthy controls. Fecal lactoferrin was 90% specific for identifying inflammation in patients with active IBD. Elevated fecal lactoferrin was 100% specific in ruling out IBS.CONCLUSIONS:Fecal lactoferrin is sensitive and specific for detecting inflammation in chronic IBD. This noninvasive test may prove useful in screening for inflammation in patients presenting with abdominal pain and diarrhea.

Fecal Lactoferrin Is a Sensitive and Specific Marker of Disease Activity in Children and Young Adults With Inflammatory Bowel Disease

Background and Aims: Fecal lactoferrin (FLA) is a neutrophil-derived surrogate marker of intestinal inflammation that is elevated in patients with inflammatory bowel disease. However, the correlation between FLA levels and serological markers of disease activity has not been previously reported, to our knowledge. In the present study we evaluated the ability of FLA levels to reflect disease activity in pediatric patients with inflammatory bowel disease. We further assessed the relationship between FLA levels and customary laboratory and clinical measures of inflammation. Patients and Methods: Fecal specimens were collected from 148 consecutive pediatric patients (79 with Crohn disease, 62 with ulcerative colitis, and 7 with irritable bowel syndrome) and 22 healthy control individuals. Lactoferrin was measured by enzyme-linked immunosorbent assay (IBD-SCAN, TECHLAB, Inc). Disease activity was assessed at the time of sample provision by laboratory measures (including erythrocyte sedimentation rate [ESR] and albumin) and previously validated disease activity indices (Pediatric Crohn Disease Activity Index, Kozarek, Harvey Bradshaw Activity Index). Results: Lactoferrin levels were significantly higher in patients with ulcerative colitis (1880 ± 565 μg/mL) (mean ± SE) or Crohn disease (1701 ± 382 μg/mL) than in healthy control individuals under 21 years of age (1.17 ± 0.47 μg/mL, P < 0.001). Lactoferrin levels correlated significantly with ESR, hematocrit, albumin, and platelet count (P < 0.001). Receiver operating characteristic curve analysis revealed that FLA levels were comparable to ESR in detecting patients with clinically active disease (P < 0.001). Patients who experienced a clinical flare within 2 months of specimen collection displayed higher lactoferrin levels (845 ± 452 μg/mL) than did those who remained in clinical remission (190 ± 90 μg/mL, P = 0.003). Conclusions: Data presented here demonstrate that FLA is a sensitive and specific biochemical marker of inflammation for use in the diagnosis and interval assessment of pediatric patients with IBD, and its level correlates well with both clinical disease activity indices and ESR. Elevated levels of FLA may also identify patients at greater risk for the development of subsequent clinical flares.

Fecal lactoferrin: a new parameter to monitor infliximab therapy.

The glycoprotein lactoferrin is found in many body fluids but also in the granules of neutrophilic granulocytes. Fecal lactoferrin levels increase quickly with the influx of leukocytes into the intestinal lumen during inflammation. This biomarker has recently been shown to be a sensitive and specific marker of disease activity in chronic inflammatory bowel disease. Our aim was the determination of fecal lactoferrin as a marker of intestinal inflammation and therapeutic response following infliximab therapy in pediatric patients with Crohns disease (CD). A total of five patients (ages 10-15 years) with severe Crohns disease as defined by the Pediatric Crohns Disease Activity Index (PCDAI) was enrolled in the study. The fecal lactoferrin levels were determined before and after therapy with infliximab by a quantitative lactoferrin ELISA (IBD-SCAN; TechLab, Inc.). Of the five patients on infliximab therapy, three received a single infusion and the remaining two underwent a regime with three maintenance infusions. All five patients responded to infliximab clinically after the first infusion, and in all patients, fecal lactoferrin levels significantly and rapidly decreased from elevated to near baseline in parallel to clinical assessment and the PCDAI. The reduction in fecal lactoferrin at days 7-10 was 93.43 ± 4.49%, in comparison with the level before infliximab therapy, and correlated with a mean decrease in the PCDAI from 48.50 to 14.0. For the patients followed during multiple infusions, one remained with mild disease and the other reached remission (subjective and PCDAI). Fecal lactoferrin is a sensitive and specific biomarker representing intestinal inflammation and response to therapy in pediatric patients with Crohns disease. It may be a helpful noninvasive diagnostic tool for monitoring therapeutic efficiency in pediatric IBD patients. Future studies are needed to further establish the relationship between endoscopic changes and the level of fecal lactoferrin as well as the possible role of lactoferrin as being an early and preclinical indicator of relapse.

Ascitic Fluid Lactoferrin for Diagnosis of Spontaneous Bacterial Peritonitis

BACKGROUND & AIMS The diagnosis of spontaneous bacterial peritonitis (SBP) is based on a manual count of ascitic fluid polymorphonuclear cells (PMNs). This procedure is operator-dependent and lysis of PMNs during transport to the laboratory may lead to false-negative results. Furthermore, ascitic fluid culture is insensitive and leads to delays in diagnosis. The aim of this study was to assess the utility of ascitic fluid lactoferrin (AFLAC) for the diagnosis of SBP and to identify a cut-off level that can be used for future development of a rapid bedside test. METHODS A total of 218 consecutive ascites samples from 148 patients (1-8 samples per patient) with cirrhosis at 2 tertiary care medical centers were examined for PMN count, bedside culture, and lactoferrin concentration. AFLAC concentrations were determined using a polyclonal antibody-based enzyme-linked immunosorbent assay. An ascitic fluid PMN count of 250 cells/mL or greater with or without a positive culture was used for diagnosis of SBP. RESULTS Twenty-two (10.1%) samples fulfilled diagnostic criteria for SBP. Samples with SBP had a significantly higher lactoferrin concentration (median, 3744 ng/mL; 25th-75th percentiles [P25-P75], 788-9617) compared with non-SBP samples (median, 31 ng/mL; P25-P75, 12-67; P < .001). By using a cut-off level of 242 ng/mL, the sensitivity and specificity of the assay for diagnosis of SBP were 95.5% and 97%, respectively. The area under the receiver operating characteristic curve was 0.98. CONCLUSIONS AFLAC can serve as a sensitive and specific test for diagnosis of SBP. Qualitative bedside assays for the measurement of AFLAC can be developed easily and may serve as a rapid and reliable screening tool for SBP in patients with cirrhosis.

Glutamate Dehydrogenase Is Highly Conserved among Clostridium difficile Ribotypes

ABSTRACT gluD was highly conserved and glutamate dehydrogenase (GDH) was readily expressed in vitro by all 77 Clostridium difficile ribotypes assayed. All ribotypes, including ARL 002, ARL 027, and ARL 106, were reactive in assays that detect C. difficile GDH.

Utility of fecal lactoferrin in identifying Crohn disease activity in children.

Objectives: Fecal lactoferrin (FL) is a noninvasive biomarker that is elevated in Crohn disease (CD) compared to irritable bowel syndrome. The purpose of this study was to evaluate FL in identifying children with active versus inactive CD. Patients and Methods: Fresh stool samples were collected from children with CD scheduled for endoscopy or a clinic visit, and from new outpatients who were scheduled for colonoscopy. FL was determined using a polyclonal antibody-based enzyme-linked immunosorbent assay. Physical global assessment, endoscopic findings, erythrocyte sedimentation rate (ESR), and the Pediatric CD Activity Index (PCDAI) were recorded for patients with CD. The PCDAI scores symptoms, laboratory parameters, physical examination, and extraintestinal manifestations. A score of ≤10 is inactive disease, 11 to 30 is mild active, and ≤31 is moderate to severe active. Results: Of 101 study patients (4- to 20-year-old, 66 boys), 31 had active CD, 23 had inactive CD, and 37 had noninflammatory bowel disease (non-IBD) conditions. Four patients with ulcerative colitis and 6 patients with polyposis were excluded from analysis. FL was significantly elevated in CD versus non-IBD (P < 0.001) and in active versus inactive CD (P < 0.001). The PCDAI and ESR were higher in active CD than in inactive CD (both P < 0.001). Using an FL cutoff of 7.25 μg/g, FL has 100% sensitivity and 100% negative predictive value in detecting active CD. Using an FL cutoff level of 60 μg/g, FL had 84% sensitivity, 74% specificity, 81% positive predictive value, and 77% negative predictive value for detecting active CD. Conclusions: FL is a promising biomarker of active CD and may be more practical to use when it is not feasible to obtain all of the necessary clinical information for the PCDAI.

Fecal Lactoferrin: Reliable Biomarker for Intestinal Inflammation in Pediatric IBD

Background. Optimal management of pediatric patients with inflammatory bowel disease (IBD) requires early diagnosis. Aim of the study is to compare fecal lactoferrin (FL) as biomarker of intestinal inflammation to CRP in pediatric patients with new-onset IBD. Methods. FL was measured by ELISA in stool specimens collected prior to endoscopy for IBD (IBD-SCAN; TechLab, Blacksburg; normal < 7.3 µg/g feces). CRP was detected in serum (normal < 5 mg/L). Three patient groups were determined: n = 21 (mean age 13.2) with Crohns disease (CD), n = 15 (mean age 10.9) with ulcerative colitis (UC), and n = 20 (mean age 11.9) in whom IBD was ruled out. In CD patients the endoscopic severity score SES-CD was correlated with the FL levels. Results. (Mean ± SEM). CRP levels were 27.18 ± 4.2 for CD-cases, 20.8 ± 9.5 for UC, and 0.24 ± 0.06 for non-IBD patients. FL levels were 313.6 ± 46.4 in CD, 370.7 ± 46.9 in UC, and 1.3 ± 0.5 in non-IBD patients. Sensitivity of CRP to detect IBD was 75% with specificity of 100%, positive predictive value of 100%, and negative predictive value of 69%. Sensitivity of FL was 100% with specificity of 95%, positive predictive value of 97.3%, and negative predictive value of 100%. In CD, FL levels correlated positively (R 2 = 0.42) with disease severity as judged by the SES-CD. Conclusions. Elevated FL corresponds to intestinal inflammation, even in patients with normal CRP. With high probability, normal FL excludes intestinal inflammation.

Assessment of Fecal ASCA Measurement as a Biomarker of Crohn Disease in Pediatric Patients

Objectives: A simple and reliable biomarker for Crohn disease (CD) would be a valuable clinical tool. We hypothesized that anti-Saccharomyces cerevisiae antibody (ASCA) may be present in the stool of patients with CD. Accordingly, we measured ASCA in the stool and serum of children and adolescents with known or suspected inflammatory bowel disease (IBD). Methods: We included 114 patients 19 years or younger (73 boys) with IBD, including 83 patients with CD and 31 subjects without CD (28 with ulcerative colitis, and 3 patients with suspected IBD but without evidence of chronic inflammation at the time of their endoscopy and colonoscopy). Fecal and serum samples were analyzed using semiquantitative ASCA enzyme-linked immunoassays. Results: Median ASCA levels were significantly elevated in the stool (P = 0.04) and serum (P = 0.0008) of patients with CD, when compared to levels observed in patients without CD. Fecal ASCA levels were similarly more elevated in patients with active CD, relative to levels observed in patients with active ulcerative colitis and acute colitis (P = 0.004). Among patients with CD, fecal and serum ASCA levels were higher (P = 0.01 and 0.01, respectively) in patients with more recently diagnosed disease. Conclusions: Fecal ASCA levels are higher in patients with active and newly diagnosed disease. Data from the present study suggest that measurement of fecal ASCA levels could represent a novel noninvasive biomarker for use in evaluating patients with suspected or known IBD. Further studies are necessary to better define the value of fecal ASCA measurements in identifying CD and response to therapy in children and young adults.

Fecal lactoferrin measurements are useful in the interval assessment of patients with active and inactive inflammatory bowel disease

Fecal lactoferrin measurements are useful in the interval assessment of patients with active and inactive inflammatory bowel disease

Measurement of anti-saccharomyces cerevisiae antibodies in human feces as a indicator of Crohn’s Disease

Introduction: The method of determining the presence of serum ASCA as a marker of Crohns disease has been used for the differentiation between Crohns disease and ulcerative colitis and has been previously published. In the following study, we describe the first noninvasive method for determining the presence of fecal ASCA. Our approach provides a highly specific method utilizing the extract of Saccharomyces cerevisiae for measuring total fecal ASCA as an aid to distinguish Crohns disease from other gastrointestinal illnesses such as ulcerative colitis and irritable bowel syndrome (IBS). Aim: To describe a novel method for detecting ASCA in human feces and evaluate the clinical utility for distinguishing Crohns disease from ulcerative colitis and IBS. Methods: Fecal ASCA levels were determined qualitatively by an enzyme-linked immunoassay (ASCA-CHEKTM ;TechLab®, Inc.). The immunoassay uses anti-human immunoglobulin antibody conjugated to HRP and microwells coated with Saccharomyces cerevisiae antigens. Fecal specimens were diluted 1:20 in the kit diluent and results were determined by measurement of the optical density (OD) at 450nm/620nm. Results of > 0.200 were considered positive for the presence of fecal ASCA. Typing of immunoglobulins in feces was done using specific human Ig conjugates. Patient Population: Ulcerative colitis (UC): 37 patients comprised of 15 females and 22 males ranging in age from 21-70. Crohns disease (CD): 49 patients comprised of 23 females and 26 males ranging in age from 21-78. Irritable bowel syndrome (IBS): 22 patients comprised of 20 females and 2 males ranging in age 19-78. Healthy control (HC): 12 persons comprised of 8 females and 4 males ranging in age from 20-79. Results: Immunoglobulin Typing of ASCA in Human Fecal Specimens