Evaluation of urinary amylase to creatinine ratio alone and in combination with urinary electrophoresis as a marker of renal damage in dogs with leishmaniosis undergoing conventional anti-Leishmania treatment

The aim of this study was to evaluate urinary amylase-to-creatinine ratio (uAm/Cr) alone and in combination with urinary sodium dodecyl-sulphate agarose gel electrophoresis (SDS-AGE) as a potential marker of renal damage in dogs with leishmaniosis at the time of diagnosis and post-treatment with meglumine antimoniate and allopurinol or miltefosine and allopurinol. Thirty-six healthy dogs and 31 dogs with leishmaniosis were enrolled in this prospective longitudinal study. Based on the initial creatinine (Cr) and urinary protein to creatinine ratio (UPC) values, leishmaniotic dogs were divided in: Group 1 if Cr was <1.4 mg/dl and UPC ≤ 0.5 (n = 14), Group 2 if Cr was <1.4 mg/dl and UPC > 0.5 (n = 11), and Group 3 if Cr was >1.4 mg/dl and a UPC > 0.5 (n = 6). According to SDS-AGE, 3 dogs had albuminuria, 4 tubular, and 20 mixed proteinuria at diagnosis. Post-treatment, 4 dogs had albuminuria, 5 tubular, 5 glomerular and 9 mixed proteinuria. At diagnosis the uAm/Cr was significantly different between all groups (P < 0.001) and after treatment decreased significantly only in Group 2 (269.7 [150.8–945] versus 8 [5–49.1], P = 0.001). At diagnosis and post-treatment, the uAm/Cr was significantly higher in dogs with mixed proteinuria (n = 20) compared to dogs with albuminuria and tubular proteinuria (n = 7) (P < 0.0001 and P = 0.003, respectively). The results suggest that uAm/cr could be a marker to evaluate renal damage at the time of diagnosis and eventual recovery after anti-Leishmania treatment, especially in dogs with proteinuria without azotemia.