The Value of Repeat <i>Clostridium difficile</i> Toxin Testing during and after an Outbreak of <i>C difficile</i>‐Associated Diarrhea
Notice bibliographique
Résumé
BACKGROUND: The recent increase in Clostridium difficile-associated diarrhea (CDAD) has led to questions about the reproducibility and sensitivity of C difficile toxin testing (CDTT). While there have been recommendations to repeat CDTT following a negative result, previous studies have failed to show a benefit. However, no studies were performed during an outbreak of CDAD. The value of repeat CDTT after an initial negative result in patients tested during and after an outbreak of CDAD is reported in the present study, as well as the reproducibility of CDTT when multiple samples are received and tested on the same day. METHODS: The results of CDTT, performed using a cell cytotoxicity assay between April 1, 2001, and March 31, 2008, were retrieved and searched for patients who had repeat samples tested after an initial negative result. The result and the number of days after a negative result were determined using the date of the most recent negative test. The cumulative positivity rate was calculated by adding all of the repeat positive test results for the days in question and dividing by the total number of tests performed during that time. RESULTS: A total of 8661 patients submitted 14,991 stool specimens for CDTT during the study period. There were 3095 samples that tested positive (20.6%) for the toxin. The results were divided into two time periods to reflect the CDAD outbreak, which began in April 2002: period 1 (outbreak) was from April 1, 2002, to March 31, 2006, and period 2 was from April 1, 2006, to March 31, 2008. The rate of positivity was 24.2% during period 1, and 11.6% during period 2 (P<0.001). Repeat CDTT was performed 619 times on samples received on the same day as the initial specimen, and only three (0.5%) were discordant. A total of 1630 samples were retested within one to seven days of a negative result, and 103 (6.3%) tested positive (7.8% period 1 and 2.9% period 2; P=0.002). The likelihood of a positive result on repeat testing in the first three days after a negative result was low (0.9%, 7% and 4%, respectively). The cumulative positivity for repeat testing performed in the first three days was 0.9%, 3.3% and 3.5%, respectively, and did not differ significantly at day 3 during the period of high CDTT positivity (P=0.110). CONCLUSIONS: The value of repeat CDTT, performed using a cell cytotoxicity assay, was low in the first three days after an initial negative result and was unchanged during a CDAD outbreak.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,004 | 0,029 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,001 | 0,001 |
| Études des sciences et des technologies | 0,001 | 0,001 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».