To scan or not to scan? Efficacy of transthoracic ultrasonography for ovine pulmonary adenocarcinoma screening in a large commercial UK sheep flock.
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:
30
12
2021
received:
29
10
2021
accepted:
18
02
2022
pubmed:
30
3
2022
medline:
9
8
2022
entrez:
29
3
2022
Statut:
ppublish
Résumé
Transthoracic ultrasonography (TTUS) is currently the only widely used method to diagnose preclinical or subclinical ovine pulmonary adenocarcinoma (OPA) in the live sheep. However, little is known about the test characteristics of TTUS. One thousand and seventy-four breeding ewes in a flock with evidence of low OPA prevalence underwent TTUS by an experienced operator. Fifty-one sheep were diagnosed with OPA and underwent gross postmortem examination (PME). Lesions consistent with OPA were found in only 24% (12/51) of the culled ewes. Thirty-five percent (18/51) of culled ewes had gross lesions consistent with other pulmonary disease and 41% (21/51) had no detectable gross lesions on PME. Histopathology and immunohistochemistry confirmed OPA in only the 12 animals identified with OPA lesions from PME. Great caution should be exercised when deciding if TTUS is an appropriate screening test in groups of sheep where OPA prevalence may be anticipated to be low. TTUS is a subjective test and thus individual operator ability will influence the sensitivity and specificity of TTUS for OPA diagnosis while the underlying prevalence influences the eventual positive predictive value.
Sections du résumé
BACKGROUND
Transthoracic ultrasonography (TTUS) is currently the only widely used method to diagnose preclinical or subclinical ovine pulmonary adenocarcinoma (OPA) in the live sheep. However, little is known about the test characteristics of TTUS.
METHODS
One thousand and seventy-four breeding ewes in a flock with evidence of low OPA prevalence underwent TTUS by an experienced operator. Fifty-one sheep were diagnosed with OPA and underwent gross postmortem examination (PME).
RESULTS
Lesions consistent with OPA were found in only 24% (12/51) of the culled ewes. Thirty-five percent (18/51) of culled ewes had gross lesions consistent with other pulmonary disease and 41% (21/51) had no detectable gross lesions on PME. Histopathology and immunohistochemistry confirmed OPA in only the 12 animals identified with OPA lesions from PME.
CONCLUSION
Great caution should be exercised when deciding if TTUS is an appropriate screening test in groups of sheep where OPA prevalence may be anticipated to be low. TTUS is a subjective test and thus individual operator ability will influence the sensitivity and specificity of TTUS for OPA diagnosis while the underlying prevalence influences the eventual positive predictive value.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
e1578Commentaires et corrections
Type : CommentIn
Informations de copyright
© 2022 The Authors. Veterinary Record Case Reports published by John Wiley & Sons Ltd on behalf of British Veterinary Association.
Références
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