Ribotype 027 Clostridium difficile infections with measurable stool toxin have increased lactoferrin and are associated with a higher mortality

We evaluated clinical and diagnostic indicators of severe C. difficile infection (CDI) and their association with poor clinical outcome. A total of 210 patients positive according to PCR (toxin B: tcdB) were included, with patients having a median age of 62 years and a Charlson co-morbidity index (CI) score of 5. Ninety-one percent (n = 191) were positive by toxigenic culture and 61 % (n = 129) had stool toxin. Toxin-positive patients had significantly higher fecal lactoferrin (mean 316 μg/g versus 106 μg/g stool; p < 0.0001). Forty percent of patients (n = 85) were infected with ribotype 027 and significantly more of these patients had measurable stool toxin (79 % vs. 50 %; p < 0.0001). The mean fecal lactoferrin was significantly higher for toxin-positive 027 CDI compared with the 027 toxin-negative group (317 vs 60 μg/g; p = 0.0014). Ribotype 027 CDI with stool toxin showed a higher all-cause, 100-day mortality compared with non-027 with stool toxin (36 % vs 18 %; p = 0.017). Logistic regression univariate analysis for odds ratio (OR) and p values revealed that age (OR = 1.1), intensive care unit treatment (OR = 2.7), CI (OR = 1.2), 027 CDI (OR = 2.1), white blood cell count (OR = 1.0), albumin level (OR = 0.1), and stool toxin-positive 027 CDI (OR = 2.5) were significantly associated with 100-day mortality (p < 0.05). In conclusion, CDI PCR-positive patients with 027 infection and stool toxin have increased lactoferrin and are at an increased risk of death.

Elevated lactoferrin is associated with moderate to severe Clostridium difficile disease, stool toxin, and 027 infection

We evaluated blood and fecal biomarkers as indicators of severity in symptomatic patients with confirmed Clostridium difficile infection (CDI). Recruitment included patients with CDI based on clinical symptoms and supporting laboratory findings. Disease severity was defined by physician’s assessment and blood and fecal biomarkers were measured. Toxigenic culture done using spore enrichment and toxin B detected by tissue culture were done as confirmatory tests. Polymerase chain reaction (PCR) ribotyping was performed on each isolate. There were 98 patients recruited, with 85 (87 %) confirmed cases of toxigenic CDI (21 severe, 57 moderate, and seven mild), of which 68 (80 %) were also stool toxin-positive. Elevated lactoferrin (p = 0.01), increased white blood cell (WBC) count (p = 0.08), and low serum albumin (p = 0.03) were all associated with the more severe cases of CDI. Ribotype 027 infection accounted for 71 % of severe cases (p < 0.01) and patients with stool toxin had significantly higher lactoferrin levels and WBC counts (p < 0.05). Our findings show that elevated fecal lactoferrin, along with increased WBC count and low serum albumin, were associated with more severe CDI. In addition, patients infected with ribotype 027 and those with stool toxin had significantly higher fecal lactoferrin and WBC counts.

Clostridium difficile prevalence rates in a large healthcare system stratified according to patient population, age, gender, and specimen consistency

We evaluated Clostridium difficile prevalence rates in 2,807 clinically indicated stool specimens stratified by inpatient (IP), nursing home patient (NH), outpatient (OP), age, gender, and specimen consistency using bacterial culture, toxin detection, and polymerase chain reaction (PCR) ribotyping. Rates were determined based on the detection of toxigenic C. difficile isolates. We identified significant differences in the rates between patient populations and with age. Specimens from NH had a higher rate (46%) for toxigenic C. difficile than specimens from IP (18%) and OP (17%). There were no gender-related differences in the rates. Liquid specimens had a lower rate (15%) than partially formed and soft specimens (25%) and formed specimens (18%) for the isolation of toxigenic C. difficile. The nontoxigenic rate was lowest for NH (4%) and highest for patients<20 years of age (23%). We identified 31 different toxigenic ribotypes from a sampling of 190 isolates that showed the lowest diversity in NH. Fluoroquinolone resistance was observed in 93% of the 027 isolates, all of the 053 isolates, and in four other ribotypes. We observed different rates for toxigenic C. difficile in stratified patient populations, with the highest rate for NH, a low overall nontoxigenic rate, and fluoroquinolone resistance.

TechLab and alexon Giardia enzyme-linked immunosorbent assay kits detect cyst wall protein 1

A Giardia lamblia antigen detected by the TechLab Giardia Test (TechLab, Inc., Blacksburg, Va.) and the Alexon ProSpecT Giardia microplate assay (Alexon, Inc., Sunnyvale, Calif.) was purified by immunoaffinity chromatography from supernatant fluids of encystment cultures. Two major proteins (Mr 22,000 and 26,000) were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Coomassie staining that did not resemble the GSA65 antigen reportedly detected by the Alexon test. These proteins reacted intensely with the monoclonal antibodies used in both commercial enzyme-linked immunosorbent assays (ELISAs). Both proteins had identical N-terminal amino acid sequences and were identified as cyst wall protein 1 (CWP1). The 26-kDa form appeared early during encystment followed by the appearance of the 22-kDa form. Recombinant CWP1 (Mr 26,000) was strongly positive in both commercial tests. CWP1 was stable in human stool specimens, resistant to degradation by proteases and N- and O-glycanases, and unaffected by oxidation with sodium periodate. Two minor proteins with Mrs of 32,000 and 39,000 were detected in CWP1 preparations by using a sensitive fluorescent protein stain. Both were identified as CWP2, and neither reacted with the monoclonal antibodies from the commercial tests. We analyzed 535 stool specimens for CWP1 by using both commercial ELISAs and resolved discrepant results by using routine ova and parasite examination (O&P) and on immunofluorescence antibody assay. The presence of CWP1 correlated well between both ELISAs (98.7% correlation). Our results demonstrate that both commercial ELISAs detect CWP1, which is a useful diagnostic marker because it is highly stable, is secreted in large amounts by encysting trophozoites, and correlates well with O&P.