title: Correlation of renal histopathology with renal echogenicity in dogs and cats: an ex-vivo quantitative study.
abstract: BACKGROUND
  Increased cortical or cortical and medullary echogenicity is one of the most common signs of chronic or acute kidney disease in dogs and cats. Subjective evaluation of the echogenicity is reported to be unreliable. Patient and technical-related factors affect in-vivo quantitative evaluation of the echogenicity of parenchymal organs. The aim of the present study is to investigate the relationship between histopathology and ex-vivo renal cortical echogenicity in dogs and cats devoid of any patient and technical-related biases.
  
  
  RESULTS
  Kidney samples were collected from 68 dog and 32 cat cadavers donated by the owners to the Veterinary Teaching Hospital of the University of Padua and standardized ultrasonographic images of each sample were collected. The echogenicity of the renal cortex was quantitatively assessed by means of mean gray value (MGV), and then histopathological analysis was performed. Statistical analysis to evaluate the influence of histological lesions on MGV was performed. The differentiation efficiency of MGV to detect pathological changes in the kidneys was calculated for dogs and cats. Statistical analysis revealed that only glomerulosclerosis was an independent determinant of echogenicity in dogs whereas interstitial nephritis, interstitial necrosis and fibrosis were independent determinants of echogenicity in cats. The global influence of histological lesions on renal echogenicity was higher in cats (23%) than in dogs (12%).
  
  
  CONCLUSIONS
  Different histopathological lesions influence the echogenicity of the kidneys in dogs and cats. Moreover, MGV is a poor test for distinguishing between normal and pathological kidneys in the dog with a sensitivity of 58.3% and specificity of 59.8%. Instead, it seems to perform globally better in the cat, resulting in a fair test, with a sensitivity of 80.6% and a specificity of 56%.
authors.affiliation: Department of Animal Medicine, Production and Health, University of Padua, Viale dell'Università 16, Legnaro (PD), 35020, Italy. alessandro.zotti@unipd.it.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Zotti
authors.affiliation: Department of Animal Medicine, Production and Health, University of Padua, Viale dell'Università 16, Legnaro (PD), 35020, Italy. tommaso.banzato@gmail.com.
authors.forename: Tommaso
authors.initials: T
authors.lastname: Banzato
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, Legnaro (PD), 35020, Italy. mariaelena.gelain@unipd.it.
authors.forename: Maria Elena
authors.initials: ME
authors.lastname: Gelain
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, Legnaro (PD), 35020, Italy. cinzia.centelleghe@gmail.com.
authors.forename: Cinzia
authors.initials: C
authors.lastname: Centelleghe
authors.affiliation: Department of Animal Medicine, Production and Health, University of Padua, Viale dell'Università 16, Legnaro (PD), 35020, Italy. calogero.vaccaro@unipd.it.
authors.forename: Calogero
authors.initials: C
authors.lastname: Vaccaro
authors.affiliation: Department of Comparative Biomedicine and Food Science, University of Padua, Viale dell'Università 16, Legnaro (PD), 35020, Italy. luca.aresu@unipd.it.
authors.forename: Luca
authors.initials: L
authors.lastname: Aresu
mesh_terms: D000818:Animals; D002102:Cadaver; D002371:Cat Diseases / Q000000981:diagnostic imaging / Q000473:pathology*; D002415:Cats; D004283:Dog Diseases / Q000000981:diagnostic imaging / Q000473:pathology*; D004285:Dogs; D005260:Female; D007668:Kidney / Q000473:pathology*; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000473:pathology / Q000662:veterinary*; D008297:Male; D014463:Ultrasonography