A specific immunoassay for detection of feline kidney injury molecule 1.

OBJECTIVES: The aim of this study was to design and carry out a preliminary evaluation of a urine point-of-care test for kidney injury molecule 1 (KIM-1) in healthy and diseased cats. METHODS: Part of the feline KIM-1 gene was amplified, ligated into a plasmid with a signal peptide and monomeric human IgGFc, and transfected into a mammalian cell line. Supernatant was purified and tested for the fusion protein by gel electrophoresis and Western blot. Mice were immunized three times with purified proteins, and hybridomas were generated from splenocytes. Antibodies were tested by ELISA for detection of recombinant KIM-1 and naturally occurring KIM-1 in disease-state urine. Next, a lateral flow assay (LFA) with capture and detection antibodies was constructed, and tested with 34 urine samples from healthy and diseased cats. Antibodies were also tested for reactivity with formalin-fixed paraffin-embedded kidney tissue. RESULTS: Three antibodies were assessed. Antibodies detected between 0.4 and 60 ng/ml feline KIM-1 fusion protein in the LFA. Urine samples from healthy cats yielded faint bands in the LFA corresponding to optical density (OD) values of 4.8-8.8. Samples from cats with suspected or confirmed acute kidney injury (AKI) had OD values ranging from 1.6-20.5. Urine KIM-1 varied over multiple days in cats with sepsis or urethral obstruction despite normalizing serum creatinine concentration. In tissue sections, KIM-1 antibodies labeled tubular cells with morphological features of injury. CONCLUSIONS AND RELEVANCE: A practical patient-side assay for detection of KIM-1 in feline urine has been developed. Preliminary results show marked though transient increases in cats with sepsis and urethral obstruction-associated AKI, and expression in injured tubules. Although initial data indicating that the LFA is sensitive and specific for KIM-1 in cats with AKI are promising, values associated with different types of injury, urine collection, urine storage and specific gravity need to be investigated.

Retro-orbital and disseminated B-cell lymphoma in a yellow-collared macaw (Primolius auricollis).

A yellow-collared macaw was presented with unilateral left exophthalmia. The complete blood cell count and biochemistry revealed a heterophilic leukocytosis and elevation in liver parameters, respectively. A computed tomography scan showed a contrast-enhancing retrobulbar mass and hepatomegaly. Cytology of the liver was consistent with a round cell tumor, most likely lymphoma. The bird died after 2 months of palliative care. Postmortem examination confirmed a retro-orbital and disseminated B-cell lymphoma.

Lymphome B rétro-orbital et disséminé chez un ara à collier jaune(Primolius auricollis). Un ara à collier jaune a été présenté avec de l'exophtalmie unilatérale gauche. La formule sanguine complète et la biochimie ont révélé une leucocytose hétérophile et une élévation des paramètres hépatiques, respectivement. La tomodensitométrie à l'aide d'une injection de milieu de contraste a montré une masse rétrobulbaire et une hépatomégalie. La cytologie du foie était conforme à une tumeur à cellules rondes, le plus probablement un lymphome. L'oiseau est mort après 2 mois de soins palliatifs. L'examen postmortem a confirmé un lymphome B rétro-orbital et disséminé.(Traduit par Isabelle Vallières).