Precollaborative Study of the GeneQuence® Salmonella Assay Using 24-Hour Enrichment Protocols for Detection of Salmonella spp. in Select Foods

Abstract New enrichment protocols are described for use with a DNA hybridization (DNAH) method for detection of Salmonella spp. in select foods. GeneQuence® Salmonella, in its original version, utilized a 3-stage enrichment of minimum 42 h duration. New 2-stage procedures of 2428 h duration are described for raw poultry, raw beef, pasteurized egg products, milk chocolate, and dry pet food. In the validation study described here, a total of 345 samples were tested by the abbreviated DNAH method in parallel with either the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA/BAM) or U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference culture procedures. Results showed an overall sensitivity for the DNAH method of 97.1% (false-negative rate 2.9%). There were no false-positive results by the DNAH method; therefore the specificity was 100%. Overall agreement between the DNAH and reference culture methods was 98.5%. There were no significant differences in performance between the DNAH and reference methods for any of the foods tested as determined by Chi-square analysis. It is recommended that the DNAH method be subjected to AOAC collaborative study.

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USDA FSIS, FDA BAM, AOAC, and ISO Culture Methods BD BBL CHROMagar Listeria Media

Journal of AOAC International ◽

10.1093/jaoac/92.4.1105 ◽

2009 ◽

Vol 92 (4) ◽

pp. 1105-1117 ◽

Cited By ~ 3

Author(s):

Vicki Ritter ◽

Susan Kircher ◽

Krista Sturm ◽

Patty Warns ◽

Nancy Dick

Keyword(s):

Ground Beef ◽

Food Samples ◽

International Organization ◽

Culture Methods ◽

Department Of Agriculture ◽

False Negatives ◽

Chi Square ◽

Smoked Salmon ◽

Inspection Service ◽

Chi Square Analysis

Abstract BBL CHROMagar Listeria Media (CL) was evaluated for detection of Listeria monocytogenes in raw ground beef, smoked salmon, lettuce, and Brie cheese. The recovery of L. monocytogenes on CL was compared to the U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM), U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS), AOAC, and International Organization for Standardization (ISO) reference-plated media using the recommended pre-enrichments and selective enrichments. Of the 265 food samples tested, 140 were tested using BAM, USDA, or AOAC methods and 125 were tested using ISO methods. CL produced comparable results with the reference methods on all matrixes with a sensitivity of 99.3 and a specificity of 100. No false negatives were found in testing the food matrixes. There was no statistical difference in recovery based on Chi-square analysis. Known isolates were evaluated, and CL had a sensitivity and specificity of 100. The results of this study demonstrate that CL is an effective medium for the recovery and detection of L. monocytogenes in raw ground beef, smoked salmon, lettuce, and Brie cheese using FDA BAM, USDA FSIS, AOAC, and ISO culture methods.

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Deoxyribonucleic Acid Hybridization Method for the Detection of Listeria in Dairy Products, Seafoods, and Meats: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/77.3.602 ◽

1994 ◽

Vol 77 (3) ◽

pp. 602-617 ◽

Cited By ~ 11

Author(s):

Michael S Curiale ◽

Terri Sons ◽

Luanne Fanning ◽

Wendy Lepper ◽

Dawn Mclver ◽

...

Keyword(s):

Dairy Products ◽

Deoxyribonucleic Acid ◽

Collaborative Study ◽

Culture Method ◽

Culture Methods ◽

Department Of Agriculture ◽

Ribosomal Ribonucleic Acid ◽

Administration Method ◽

Inspection Service ◽

The U.S

Abstract The method is based on the hybridization of synthetic deoxyribonucleic acid probes to ribosomal ribonucleic acid sequences unique to Listeria. This method was compared to 2 culture methods: the U.S. Food and Drug Administration method for the detection of Listeria in dairy products and sea-foods and the U.S. Department of Agriculture, Food Safety and Inspection Service method for Listeria in meats. Six food types with replicate samples containing various concentrations of Listeria were analyzed by the collaborating laboratories. Listeria was detected in 774 samples using the DNAH method and in 772 samples using a culture method. The DNAH and culture methods were in agreement for 668 samples containing Listeria and 306 samples without Listeria. The overall rate of agreement between methods was 82.3%. The method has been adopted first action by AOAC INTERNATIONAL.

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DuPont Qualicon BAX® System Assay for Genus Listeria 24E

Journal of AOAC International ◽

10.1093/jaoac/94.3.863 ◽

2011 ◽

Vol 94 (3) ◽

pp. 863-871

Author(s):

F Morgan Wallace ◽

Dawn Fallon ◽

Daniel DeMarco ◽

Stephen Varkey

Keyword(s):

False Negative ◽

Method Comparison ◽

Culture Methods ◽

Department Of Agriculture ◽

Service Culture ◽

Steel Surfaces ◽

Consistent Performance ◽

Inspection Service ◽

Positive Results ◽

The U.S

Abstract The new BAX® System PCR Assay for Genus Listeria 24E was evaluated for detecting Listeria spp. in frankfurters, spinach, cooked shrimp, queso fresco cheese, and on stainless steel surfaces with a single-stage enrichment in BAX System 24 Listeria Enrichment Broth (24 LEB). Method comparison studies performed on samples with low-level inoculates showed that the BAX System demonstrates a sensitivity equivalent or superior to the U.S. Food and Drug Administration's Bacteriological Analytical Manual and the U.S. Department of Agriculture-Food Safety and Inspection Service culture methods, but with a significantly shorter time to result. Tests to evaluate inclusivity and exclusivity returned no false-negative and no false-positive results on a diverse panel of isolates, and tests for lot-to-lot variability and tablet stability demonstrated consistent performance. Ruggedness studies determined that none of the factors examined, within the range of deviations from specified parameters examined, affect the performance of the assay.

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Evaluation of the Assurance GDS™ for E. coli O157:H7 Method and Assurance GDS for Shigatoxin Genes Method in Selected Foods: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/88.5.1334 ◽

2005 ◽

Vol 88 (5) ◽

pp. 1334-1348 ◽

Cited By ~ 7

Author(s):

Philip T Feldsine ◽

Shannon T Green ◽

Andrew H Lienau ◽

James Stephens ◽

Markus T Jucker ◽

...

Keyword(s):

Orange Juice ◽

Collaborative Study ◽

Ground Beef ◽

Culture Methods ◽

Chi Square ◽

E Coli ◽

Reference Methods ◽

Uninoculated Control ◽

Chi Square Analysis ◽

Better Than

Abstract A multilaboratory collaborative study was conducted to compare the Assurance GDS™ for E. coli O157:H7 method and the reference culture methods for the detection of E. coli O157:H7 in orange juice, raw ground beef, and fresh lettuce. A separate companion assay, the Assurance GDS for Shigatoxin Genes method was also evaluated with the same test portions. Fifteen laboratories participated in the study. A Chi square analysis of each of the 3 food types at the high, low, and uninoculated control levels was performed. For all foods, the Assurance GDS for E. coli O157:H7 method and the Assurance GDS for Shigatoxin Genes method were equivalent to or better than the reference methods.

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VIDAS® Listeria species Xpress (LSX)

Journal of AOAC International ◽

10.5740/jaoacint.govval04 ◽

2013 ◽

Vol 96 (2) ◽

pp. 242-245 ◽

Cited By ~ 1

Author(s):

Ronald Johnson ◽

John Mills

Keyword(s):

Stainless Steel ◽

Reference Method ◽

Culture Method ◽

Culture Methods ◽

Chi Square ◽

Listeria Species ◽

Standard Culture ◽

Inspection Service ◽

Chi Square Analysis ◽

Positive Results

Abstract The AOAC GovVal study compared the VIDAS®Listeria species Xpress (LSX) to the Health Products and Food Branch MFHPB-30 reference method for detection of Listeria on stainless steel. The LSX method utilizes a novel and proprietary enrichment media, Listeria Xpress broth, enabling detection of Listeria species in environmental samples with the automated VIDAS in a minimum of 26 h. The LSX method also includes the use of the chromogenic media, chromID™ Ottaviani Agosti Agar (OAA) and chromID™ Lmono for confirmation of LSX presumptive results. In previous AOAC validation studies comparing VIDAS LSX to the U. S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) and the U. S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference methods, the LSX method was approved as AOAC Official Method2010.02 for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry, and as AOAC Performance Tested Method 100501 in a variety of foods and on environmental surfaces. The GovVal comparative study included 20 replicate test portions each at two contamination levels for stainless steel where fractionally positive results (5–15 positive results/20 replicate portions tested) were obtained by at least one method at one level. Five uncontaminated controls were included. In the stainless steel artificially contaminated surface study, there were 25 confirmed positives by the VIDAS LSX assay and 22 confirmed positives by the standard culture methods. Chi-square analysis indicated no statistical differences between the VIDAS LSX method and the MFHPB-30 standard methods at the 5% level of significance. Confirmation of presumptive LSX results with the chromogenic OAA and Lmono media was shown to be equivalent to the appropriate reference method agars. The data in this study demonstrate that the VIDAS LSX method is an acceptable alternative method to the MFHPB-30 standard culture method for the detection of Listeria species on stainless steel.

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USDA FSIS, FDA BAM, and ISO Culture Methods BD BBL CHROMagar O157 Media

Journal of AOAC International ◽

10.1093/jaoac/92.4.1118 ◽

2009 ◽

Vol 92 (4) ◽

pp. 1118-1127 ◽

Cited By ~ 1

Author(s):

Vicki Ritter ◽

Susan Kircher ◽

Nancy Dick

Keyword(s):

Ground Beef ◽

Reference Method ◽

Food Samples ◽

Culture Methods ◽

Chi Square ◽

Apple Cider ◽

E Coli ◽

Inspection Service ◽

Chi Square Analysis ◽

Method Agreement

Abstract BBL CHROMagar O157 media (CO) was evaluated for detection of Escherichia coli O157:H7 in raw ground beef and unpasteurized apple cider. The recovery of E. coli O157:H7 on CO was compared to the U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM), U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS), and International Organization for Standardization (ISO) reference-plated media using the recommended enrichment broths. Of the 180 food samples tested, 45 were tested using BAM, 45 using the USDA method, and 90 using the ISO method. CO produced comparable results with the reference methods on all matrixes with a sensitivity of 100 and a specificity of 100. No false negatives were found in testing the food matrixes. There was no statistical difference in recovery based on Chi-square analysis. Method agreement for raw ground beef was 85 for the USDA FSIS method and 95 for the ISO method. Method agreement for unpasteurized apple cider was 100 for the ISO and FDA BAM methods. In all cases where method agreement was <100, CO detected more positives than the reference method media. Evaluation of known isolates on CO in inclusivity and exclusivity testing had a sensitivity and specificity of 100. The results of this study demonstrate that CO is an effective medium for the recovery and detection of E. coli O157:H7 in raw ground beef and unpasteurized apple cider using FDA BAM, USDA FSIS, and ISO methods.

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RapidChek SELECT Salmonella

Journal of AOAC International ◽

10.1093/jaoac/92.6.1890 ◽

2009 ◽

Vol 92 (6) ◽

pp. 1890-1894 ◽

Cited By ~ 8

Author(s):

Mark T Muldoon ◽

Jingkun Li ◽

Meredith Sutzko ◽

Ann Christine Olsson-Allen ◽

George Teaney ◽

...

Keyword(s):

False Positive Rate ◽

Peanut Butter ◽

False Negative ◽

False Negative Rate ◽

Reference Method ◽

Salmonella Spp ◽

Chi Square ◽

Negative Results ◽

Significant Difference ◽

Positive Rate

Abstract RapidChek SELECT Salmonella was previously validated in the Performance Tested MethodsSM program for the detection of Salmonella spp. in raw ground chicken, chicken carcass rinse, sliced cooked turkey, and liquid eggs. The present matrix extension study conducted under the AOAC Research Institute Emergency Response Validation program compared the RapidChek SELECT Salmonella method to the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) method for the detection of Salmonella Typhimurium in peanut butter. Overall, 27 samples were found positive by the RapidChek SELECT Salmonella method and 27 were found to be positive by the reference method. All RapidChek SELECT Salmonella presumptive positives were confirmed positive by the cultural reference method; additionally, all presumptive negative results were confirmed negative by the cultural reference method. Accordingly 0 false-negative rate and 0 false-positive rate were found. No significant difference between the RapidCheck SELECT Salmonella and FDA-BAM reference method was found; calculated Chi-square was 0. Results indicate that a low level of Salmonella in peanut butter can be successfully recovered and detected in the minimum 24 h enrichment protocol.

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Singlepathr® Salmonella: Performance-Tested MethodSM 060401

Journal of AOAC International ◽

10.1093/jaoac/89.2.417 ◽

2006 ◽

Vol 89 (2) ◽

pp. 417-432 ◽

Cited By ~ 4

Author(s):

Lisa Thompson ◽

Charlotte Lindhardt ◽

Joseph Odumeru ◽

Joseph D Eifert

Keyword(s):

False Positive Rate ◽

False Negative ◽

False Negative Rate ◽

Reference Method ◽

Black Pepper ◽

Salmonella Spp ◽

Chi Square ◽

Qualitative Detection ◽

Significant Difference ◽

Positive Rate

Abstract Singlepath® Salmonella is an immunochromatographic (lateral flow) assay for the presumptive qualitative detection of Salmonella spp. in food. The AOAC Performance-Tested MethodSM study evaluated Singlepath Salmonella as an effective method for the detection of Salmonella spp. in the following selected foods: dried skimmed milk, black pepper, dried pet food, desiccated coconut, cooked peeled frozen prawns, raw ground beef, and raw ground turkey. When the foods were inoculated with Salmonella spp. at levels ranging from low 0.23–1.08 colony forming units (CFU)/25 g to high (2.3–6.0 CFU/25 g), a Chi-square value of 0.9 indicated that there was no significant difference between Singlepath Salmonella and the ISO 6579:2002 reference method. Singlepath Salmonella gave a false-positive rate of 7.3% and a false-negative rate of 2.5%. For the inclusivity study, all 105 Salmonella serovars reacted with Singlepath Salmonella. For the exclusivity study, 58 non-Salmonella spp. were tested. There were no cross-reactions with Singlepath Salmonella from these strains.

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Diagnostic Value of a Carpal Tunnel Corticosteroid Injection in Patients with Negative Electrodiagnostic Studies

Journal of Hand and Microsurgery ◽

10.1055/s-0040-1717830 ◽

2020 ◽

Author(s):

Brian M. Katt ◽

Casey Imbergamo ◽

Fortunato Padua ◽

Joseph Leider ◽

Daniel Fletcher ◽

...

Keyword(s):

Carpal Tunnel ◽

Corticosteroid Injection ◽

Carpal Tunnel Release ◽

False Negative ◽

False Negative Rate ◽

Signs And Symptoms ◽

Diagnostic Value ◽

Symptom Improvement ◽

Study Cohort ◽

Chi Square Analysis

Abstract Introduction There is a known false negative rate when using electrodiagnostic studies (EDS) to diagnose carpal tunnel syndrome (CTS). This can pose a management dilemma for patients with signs and symptoms that correlate with CTS but normal EDS. While corticosteroid injection into the carpal tunnel has been used in this setting for diagnostic purposes, there is little data in the literature supporting this practice. The purpose of this study is to evaluate the prognostic value of a carpal tunnel corticosteroid injection in patients with a normal electrodiagnostic study but exhibiting signs and symptoms suggestive of carpal tunnel, who proceed with a carpal tunnel release. Materials and Methods The group included 34 patients presenting to an academic orthopedic practice over the years 2010 to 2019 who had negative EDS, a carpal tunnel corticosteroid injection, and a carpal tunnel release. One patient (2.9%), where the response to the corticosteroid injection was not documented, was excluded from the study, yielding a study cohort of 33 patients. Three patients had bilateral disease, yielding 36 hands for evaluation. Statistical analysis was performed using Chi-square analysis for nonparametric data. Results Thirty-two hands (88.9%) demonstrated complete or partial relief of neuropathic symptoms after the corticosteroid injection, while four (11.1%) did not experience any improvement. Thirty-one hands (86.1%) had symptom improvement following surgery, compared with five (13.9%) which did not. Of the 32 hands that demonstrated relief following the injection, 29 hands (90.6%) improved after surgery. Of the four hands that did not demonstrate relief after the injection, two (50%) improved after surgery. This difference was statistically significant (p = 0.03). Conclusion Patients diagnosed with a high index of suspicion for CTS do well with operative intervention despite a normal electrodiagnostic test if they have had a positive response to a preoperative injection. The injection can provide reassurance to both the patient and surgeon before proceeding to surgery. Although patients with a normal electrodiagnostic test and no response to cortisone can still do well with surgical intervention, the surgeon should carefully review both the history and physical examination as surgical success may decrease when both diagnostic tests are negative. Performing a corticosteroid injection is an additional diagnostic tool to consider in the management of patients with CTS and normal electrodiagnostic testing.

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Qualitative Map of Salmonella Contamination on Young Chicken Carcasses†

Journal of Food Protection ◽

10.4315/0362-028x-73.9.1596 ◽

2010 ◽

Vol 73 (9) ◽

pp. 1596-1603 ◽

Cited By ~ 11

Author(s):

T. P. OSCAR ◽

G. K. RUTTO ◽

J. B. LUDWIG ◽

S. PARVEEN

Keyword(s):

Public Health ◽

Antibiotic Resistance ◽

Public Health Problem ◽

Global Public Health ◽

Culture Methods ◽

Chi Square ◽

Conventional Culture ◽

Chicken Carcass ◽

Young Chicken ◽

Chi Square Analysis

Salmonella contamination of poultry is a global public health problem. The objective of this study was to map the distribution of Salmonella on the young chicken carcass, to improve poultry inspection and food safety. Young chickens (n = 70) in the Cornish game hen class were obtained at retail over a 3-year period. Carcasses were aseptically sectioned into 12 parts, and then Salmonella was isolated from whole-part incubations by conventional culture methods. Isolates were characterized for serotype and antibiotic resistance, and by pulsed-field gel electrophoresis (PFGE). Salmonella incidence was 21.5% (181 of 840) for parts and 57.1% (40 of 70) for carcasses. The number of contaminated parts per carcass ranged from 0 to 12, with a mean of 4.5 among contaminated carcasses. Chi-square analysis indicated that Salmonella incidence differed (P < 0.05) among parts, with rib back (38.6%) and sacral back (34.3%) being the most contaminated. Among the 40 contaminated carcasses, there were 37 different patterns of contamination among parts. Of the 33 carcasses with more than one contaminated part, 12.1% contained two serotypes, 33.3% contained two or more antibiotic resistance profiles, and 100% contained two or more PFGE patterns. The most common serotype was Typhimurium (94.5%), and most (97.2%) isolates were resistant to multiple antibiotics. These results indicated a diverse pattern of Salmonella contamination among carcasses and that multiple subtypes of Salmonella were often present on contaminated carcasses. Thus, whole-carcass incubation succeeded by characterization of multiple isolates per carcass is needed to properly assess and manage this risk to public health.

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