Efficacy of high-throughput transthoracic ultrasonographic screening for on-farm detection of ovine pulmonary adenocarcinoma.
Journal
The Veterinary record
ISSN: 2042-7670
Titre abrégé: Vet Rec
Pays: England
ID NLM: 0031164
Informations de publication
Date de publication:
08 2022
08 2022
Historique:
revised:
28
03
2022
received:
09
11
2021
accepted:
11
05
2022
pubmed:
6
7
2022
medline:
9
8
2022
entrez:
5
7
2022
Statut:
ppublish
Résumé
The aim of this study was to evaluate the efficacy of high-throughput on-farm transthoracic ultrasound (TUS) to screen for ovine pulmonary adenocarcinoma (OPA), an infectious ovine disease of increasing concern. No other routine diagnosis of preclinical OPA is available, or any vaccine or treatment. More than 80,000 rapid TUS scans were applied on farms with a history of OPA. The TUS results from a convenience sample of 171 TUS-negative and 269 TUS-positive sheep were compared with postmortem histology/immunohistochemistry results, the 'gold standard' reference test for OPA diagnosis. These results, together with new data on within-flock prevalence, allowed estimation of the efficacy of rapid TUS screening to identify OPA (defined as tumours of larger than 1 cm) on-farm. The TUS screening had an estimated specificity of 0.998 (95% confidence interval [CI]: 0.998-0.999) and an estimated sensitivity of between 0.76 (95% CI: 0.72-0.79) and 0.99 (95% CI: 0.97-0.99) depending on the presumed false-negative rate applied to the calculation. High-throughput TUS should be considered for screening to identify individual sheep with OPA and has potential application to indicate flocks at low risk of OPA. However, lower efficacy is likely if conducted by less experienced persons.
Sections du résumé
BACKGROUND
The aim of this study was to evaluate the efficacy of high-throughput on-farm transthoracic ultrasound (TUS) to screen for ovine pulmonary adenocarcinoma (OPA), an infectious ovine disease of increasing concern. No other routine diagnosis of preclinical OPA is available, or any vaccine or treatment.
METHODS
More than 80,000 rapid TUS scans were applied on farms with a history of OPA. The TUS results from a convenience sample of 171 TUS-negative and 269 TUS-positive sheep were compared with postmortem histology/immunohistochemistry results, the 'gold standard' reference test for OPA diagnosis. These results, together with new data on within-flock prevalence, allowed estimation of the efficacy of rapid TUS screening to identify OPA (defined as tumours of larger than 1 cm) on-farm.
RESULTS
The TUS screening had an estimated specificity of 0.998 (95% confidence interval [CI]: 0.998-0.999) and an estimated sensitivity of between 0.76 (95% CI: 0.72-0.79) and 0.99 (95% CI: 0.97-0.99) depending on the presumed false-negative rate applied to the calculation.
CONCLUSION
High-throughput TUS should be considered for screening to identify individual sheep with OPA and has potential application to indicate flocks at low risk of OPA. However, lower efficacy is likely if conducted by less experienced persons.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
e1797Informations de copyright
© 2022 British Veterinary Association.
Références
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