Proteinuric Dogs Research Articles

Factors associated with thrombotic disease in dogs with renal proteinuria: A retrospective of 150 cases.

Knowledge of additional risk factors for thrombotic disease (TD) among dogs with renal proteinuria is limited; these might differ for TD affecting the systemic arterial (AT), systemic venous (VT), and pulmonary circulation (PT). To compare signalment and clinicopathological data between dogs with renal proteinuria with or without TD, and between dogs with AT, VT, and PT. One hundred fifty client-owned dogs with renal proteinuria, 50 of which had TD. Retrospective case-controlled study. A database search (2004-2021) identified proteinuric dogs (UPC > 2) with and without TD. Clinicopathological data were obtained from the records. TD and non-TD (NTD) groups were compared by binary logistic regression, and AT, VT, and PT groups by multinomial regression. Normal data presented as mean ± SD, non-normal data presented as median [25th, 75th percentiles]. Cavalier King Charles Spaniels were overrepresented in the TD group (OR = 98.8, 95% CI 2.09-4671, P = .02). Compared to NTD cases, TD cases had higher concentration of neutrophils (11.06 [8.92, 16.58] × 109 /L vs 7.31 [5.63, 11.06] × 109 /L, P = .02), and lower concentration of eosinophils (0 [0, 0.21] × 109 /L vs 0.17 [0.04, 0.41] × 109 /L, P = .002) in blood, and lower serum albumin (2.45 ± 0.73 g/dL vs 2.83 ± 0.73 g/dL, P = .04). AT cases had higher serum albumin concentrations than VT cases (2.73 ± 0.48 g/dL vs 2.17 ± 0.49 g/dL, P = .03) and were older than PT cases (10.6 ± 2.6 years vs 7.0 ± 4.3 years, P = .008). VT cases were older (9.1 ± 4.2 years vs 7.0 ± 4.3 years, P = .008) and had higher serum cholesterol concentration (398 [309-692 mg/dL] vs 255 [155-402 mg/dL], P = .03) than PT cases. Differences between thrombus locations could reflect differences in pathogenesis.

MicroRNA-126 in dogs with immune complex-mediated glomerulonephritis.

Most proteinuric dogs with naturally occurring chronic kidney disease have amyloidosis (AMYL), glomerulosclerosis (GS), or immune complex-mediated glomerulonephritis (ICGN), each with different treatment and prognosis. A noninvasive and disease-specific biomarker is lacking. We hypothesized that the expression pattern of biofluid microRNA (miRNAs and miRs) would correlate with disease progression and categorization. Archived serum and urine samples from 18 dogs with glomerular disease and 6 clinically healthy dogs; archived urine samples from 49 dogs with glomerular disease and 13 clinically healthy dogs. Retrospective study. Archived biofluid samples from adult dogs with biopsy-confirmed glomerular disease submitted to the International Veterinary Renal Pathology Service between 2008 and 2016 were selected. Serum and urinary miRNAs were isolated and profiled using RNA sequencing. Urinary miR-126, miR-21, miR-182, and miR-486 were quantified using quantitative reverse transcription PCR. When comparing more advanced disease with earlier disease, no serum miRNAs were differentially expressed, but urinary miR-21 and miR-182 were 1.63 (95% CI: .86-3.1) and 1.45 (95% CI: .82-2.6) times higher in azotemic dogs, respectively (adjusted P < .05) and weakly correlated with tubulointerstitial fibrosis (miR-21: r = .32, P = .03; miR-182: r = .28, P = .05). Expression of urinary miR-126 was 10.5 (95% CI: 4.1-26.7), 28.9 (95% CI: 10.5-79.8), and 126.2 (95% CI: 44.7-356.3) times higher in dogs with ICGN compared with dogs with GS, AMYL, and healthy controls, respectively (P < .001). The miR-126 could help identify dogs that might benefit from immunosuppressive therapy in the absence of a biopsy. MiR-21 and miR-182 are potential markers of disease severity and fibrosis.

The Relevance of Screening for Vector-Borne Diseases in Dogs with Proteinuria Living in an Endemic Region: A Retrospective Study.

This study aims to assess the main causes of proteinuria in dogs from the region of Lisbon (Portugal), estimating the relevance of screening for canine vector-borne diseases (CVBDs). A cross-sectional retrospective study was conducted. Medical records from proteinuric dogs (urinary protein–creatinine ratio > 0.5) presented to a Veterinary Teaching Hospital over a two-year period were reviewed for signalment, established diagnosis, proteinuria origin, and CVBD screening results. A total of 106 dogs were included. The median age was 9.5 years old (IQR: 7–12). Proteinuria was considered of renal origin in 76% of cases (46% of them had a presumptive diagnosis of glomerulonephritis secondary to CVBD, 27% chronic kidney disease, 26% systemic disease possible to induce proteinuria, and 1% leptospirosis). Proteinuria was classified as post-renal or mixed-origin in 17% and 7% of cases, respectively. About 35% of proteinuric dogs were positive for at least one CVBD. Of them, 84% were seropositive for one CVBD, while 16% tested positive for two or more. Among dogs testing positive for CVBD, 89% were seropositive for Leishmania infantum. This study showed that about one-third of proteinuric dogs tested positive for CVBDs, highlighting the relevance of their screening in dogs with proteinuria living in endemic regions.

Point prevalence and clinical course of proteinuria in dogs with idiopathic non-erosive immune-mediated polyarthritis.

ObjectivesTo describe the point prevalence and clinical course of proteinuria in dogs diagnosed with idiopathic non‐erosive immune‐mediated polyarthritis.Materials and MethodsCases presenting to a single referral centre with a diagnosis of idiopathic non‐erosive immune‐mediated polyarthritis were retrospectively recruited from January 2009 to August 2018. Data including signalment, urinalysis, clinicopathological results, cytology from arthrocentesis, treatment and long‐term follow‐up were analysed. Dogs were defined as: non‐proteinuric (UPC <0.2), borderline proteinuric (UPC 0.2‐0.5) or overtly proteinuric (UPC >0.5).ResultsFifty‐eight dogs met the inclusion criteria. Twenty‐two dogs were overtly proteinuric (38%), eight dogs were borderline proteinuric (14%) and 28 dogs were non‐proteinuric (48%). Repeated urinalysis was performed in nine of 12 dogs with UPC greater than 2.0. The UPC decreased in all nine dogs, with the UPC decreasing to less than 0.5 in 44% of dogs. A greater than 50% decrease in UPC was noted in 44% of dogs, despite seven of nine (77%) receiving prednisolone as either monotherapy or in conjunction with an adjunctive immunosuppressive medication.Clinical SignificanceProteinuria was common in this cohort of dogs diagnosed with primary idiopathic non‐erosive immune‐mediated polyarthritis. The use of prednisolone does not appear to be contraindicated in proteinuric dogs with idiopathic non‐erosive immune‐mediated polyarthritis.

Book Review: Atlas of Renal Lesions in Proteinuric Dogs

Book Review: Atlas of Renal Lesions in Proteinuric Dogs

Characteristics associated with bacterial growth in urine in 451 proteinuric dogs (2008-2018).

BackgroundUrine cultures are frequently recommended to rule out infection as a postrenal cause of proteinuria.ObjectiveIdentify characteristics associated with bacterial growth in urine in proteinuric dogs.AnimalsFour hundred and fifty‐one dogs admitted to a teaching hospital between January 2008 and January 2018 with urine protein‐to‐creatinine ratios (UPCs) >0.5.MethodsRetrospective study included dogs with a UPC, urinalysis, and quantitative urine culture (QUC) performed within a 72‐hour period by searching electronic records. Dogs with recent antimicrobial therapy, urine collected by methods other than cystocentesis, or UPC ≤0.5 were excluded. Signalment, comorbidities, serum BUN and creatinine concentrations, urinalysis findings, and QUC results were recorded. The association between these characteristics and presence of bacterial growth in urine was assessed by univariable and multivariable analysis.ResultsThirty of four hundred fifty‐one dogs (6.7%) had bacterial growth in urine. Of these, 18 (60.0%) had active urine sediment. Bacterial growth in urine was associated with pyuria (odd ratio [OR] 25.1, 95% confidence interval [CI] 7.9‐79.6, P < .001), bacteriuria (OR 11.1, 95% CI 3.2‐39.1, P < .001), and lower urinary tract disease (OR 6.7, 95% CI 1.9‐23.0; P = .0028). If QUC was prompted based on these criteria, 8/451 (1.8%) of proteinuric dogs would have had undetected bacterial growth.Conclusions and Clinical ImportanceThe proportion of proteinuric dogs with both inactive urine sediment and bacterial growth in urine was low, suggesting that QUC might not be necessary in the evaluation of all proteinuric dogs. An active urine sediment or lower urinary tract disease should prompt QUC for proteinuric dogs.

A retrospective study of vector-borne disease prevalence in dogs with proteinuria: Southeastern United States.

BackgroundProteinuria is a risk factor for progressive kidney injury in dogs. Enhanced understanding of potential associations between canine vector‐borne diseases (CVBD) and proteinuria is needed.ObjectivesTo determine the proportion of evaluated proteinuric dogs exposed to ≥1 CVBD, including Babesia spp., Ehrlichia spp., spotted‐fever group Rickettsia, Bartonella spp., Anaplasma spp., hemotropic Mycoplasma spp., Borrelia burgdorferi, and Dirofilaria immitis, and to determine if demographic or clinicopathologic differences exist between proteinuric dogs exposed to CVBD versus proteinuric dogs with no evidence of CVBD exposure.AnimalsTwo‐hundred nine proteinuric dogs, concurrently tested for CVBD, which were examined at a single academic veterinary hospital between January 2008 and December 2015.MethodsRetrospective cross‐sectional study. Demographic, clinicopathologic, and CVBD test results were extracted from medical records. A multivariable logistic regression model was used to assess associations between CVBD and selected variables.ResultsBased on serology and polymerase chain reaction testing, 34% of proteinuric dogs (72/209) were exposed to ≥1 CVBD. Exposure to Rickettsia spp. (19%), Ehrlichia spp. (12%), and B. burgdorferi (9%) were most common. The CVBD exposure was lower in dogs tested in autumn or spring, higher in intact dogs, and higher in dogs with lower serum albumin and higher serum creatinine concentrations.Conclusions and Clinical ImportanceExposure to CVBD, particularly exposure to Rickettsia spp., Ehrlichia spp., and B. burgdorferi was found in proteinuric dogs from the southeast United States. Additional controlled prospective studies examining a potential causal relationship between CVBD and proteinuria are warranted.

Prevalence of Proteinuria in Owned Dogs from Italy: A Multicentric Study.

Even though proteinuria is related to different causes, when it is persistent and associated with inactive urinary sediment, it is primarily due to kidney disease. Early detection of proteinuria allows us to identify several pathological conditions. The aim of the study was screening a canine population not known as being proteinuric, by the urinary dipstick. The study was carried out in seven Italian veterinary clinics during a period of six weeks. Dogs were enrolled with no restriction of sex or age. Females in estrus, dogs with signs of genitourinary diseases, or those previously diagnosed with proteinuric nephropathy were excluded. Dogs were considered “nonproteinuric” (NP) in case of negative dipstick test or “suspected proteinuric” (SP), if positive at the dipstick. When possible, proteinuria was confirmed by UPC ratio. A total of 1156 dogs were evaluated: 414 were from northern Italy and 742 from southern Italy. Based on dipstick test, 655 (56.6%) dogs were NP, while 501 (43.3%) were SP. Among the NP dogs 225 out of 414 (54.3%) were in northern Italy and 430 of 742 (57.9%) in southern Italy. One hundred eighty-nine of 414 (45.7%) SP dogs were identified in northern Italy and 312 of 742 (42.1%) in southern Italy. No statistical difference was found between the North and the South of Italy. UPC was available in 412 out of 501 SP samples: proteinuria was confirmed in 263 (63.86%) samples. Results from our study showed a high percentage of suspected proteinuric dogs, apparently not affected by renal diseases, together with the absence of statistically significant differences based on geographical area.

Effect of common storage temperatures and container types on urine protein : creatinine ratios in urine samples of proteinuric dogs.

BackgroundPreanalytic protein adsorption to polymer and glass container surfaces may decrease urine protein concentration measurements and urine protein: creatinine ratios (UPC).Hypothesis/ObjectivesUrine stored in PC or glass containers will have lower UPC than urine stored in HP containers. The specific objective was to determine whether clinically relevant differences in UPC would be detected after storage in glass, PC, or HP containers using common storage times and temperatures.AnimalsTwelve client‐owned dogs with proteinuria.MethodsProspective, nonmasked study, divided into 2 phases. The first phase was a pilot study involving multiple (n = 5) measurements at each storage condition using 24‐hours urine samples from 2 dogs with persistent renal proteinuria of different magnitude. The second phase used urine samples from 10 dogs with proteinuria of variable magnitude. Sample aliquots were stored in HP, PC, and glass containers at 24°C for 4 hours, 4°C for 12 hours, and −20°C for 72 hours. The UPC of each was measured after storage and compared with baseline.ResultsStatistically significant but clinically irrelevant differences were found in phase 1. In phase 2, storage conditions did not affect urinary protein or creatinine concentrations or UPC.Conclusions and Clinical ImportanceCollection and storage of canine urine samples in clean HP, PC, or glass containers at 24°C for 4 hours, 4°C for 12 hours, or −20°C for 72 hours is unlikely to result in clinically relevant decreases in measured UPC values.

Serum Symmetric Dimethylarginine as an Early Marker of Excretory Dysfunction in Canine Leishmaniosis (L. infantum) Induced Nephropathy.

The aims of the study were to determine whether symmetric dimethylarginine (SDMA) was increased in dogs with leishmaniosis and to assess its relationship with creatinine concentration and urinary protein : creatinine ratio (UPC) to determine its utility as a marker of early excretory dysfunction. Fifty-three dogs with leishmaniosis classified according to the LeishVet clinical staging (stage I, n = 5, stage II, n = 30; stage III, n = 12; stage IV, n = 6) were selected and compared with 41 clinically healthy dogs. Thirty-nine dogs with leishmaniosis were also followed up for six months. SDMA concentrations on the day of diagnosis were significantly higher in dogs with leishmaniosis with respect to control dogs and in dogs from LeishVet stage IV when compared with the other stages. Increased UPC (>0.5), SDMA (>19 μg/dL), and creatinine concentrations (≥1.4 mg/dL) were found in 47.1%, 15.1%, and 9.4% of dogs with leishmaniosis, respectively. SDMA concentration was increased in 24% of proteinuric dogs, in 7% of nonproteinuric dogs, and in four of five dogs with increased creatinine. SDMA concentration ≥ 25 μg/dL was associated with clinical chronic kidney disease (CKD) after six months. Our results did not demonstrate advantages in using SDMA concentration as an early marker of CKD when compared to creatinine and UPC in canine leishmaniosis.

Short-term effects of dietary supplementation with amino acids in dogs with proteinuric chronic kidney disease.

This retrospective study investigated the impact of amino acid supplementation on body weight, serum albumin, creatinine and urea concentrations, and urine protein-to-creatinine (UPC) ratio in proteinuric dogs with chronic kidney disease (CKD). Forty-six client-owned azotemic dogs with spontaneous proteinuric CKD already on a renal diet and in therapy with enalapril were included. After approximately 1 month of treatment (baseline), 29 dogs received oral amino acid supplementation daily (group A) and 17 dogs did not (group B). The parameters under investigation were determined at baseline and after 4 to 8 weeks in both groups. Compared to baseline, body weight and serum albumin increased (P < 0.01, P < 0.05, respectively) at follow-up in group A, but did not change in group B. Serum creatinine concentration did not change in both groups; urea concentration (P < 0.05) and UPC ratio (P < 0.01) decreased in group B, but not in group A. Supplementation with amino acids increased body weight and serum albumin concentration in these dogs but it might have prevented a decrease in proteinuria and urea concentration.

Measurement of proteinuria in dogs: analytic and diagnostic differences using 2 laboratory methods.

Urinary protein-to-creatinine (UPC) ratio is an early diagnostic and prognostic marker of renal disease in dogs. Pyrogallol red molybdate (PRM) and Coomassie brilliant blue (CBB) are the most popular dye-binding assays for measurement of proteinuria. Published guidelines recommend strict cut-off points to substage patients with chronic renal diseases, irrespective of the assay applied. However, analytic variability and method-dependent differences could affect substaging of patients. The aims of this study were to analytically validate the CBB assay to evaluate possible method-dependent differences with PRM in urinary protein (UP) determination, and to assess the influence of such differences in substaging according to the International Renal Interest Society (IRIS). Urine was collected from healthy and proteinuric dogs. Intra-assay and inter-assay repeatability (imprecision), linearity under dilution (LUD), and spiking recovery (inaccuracy) were determined for the CBB assay. Split samples were measured with PRM and CBB, and agreement between methods and concordance in classification according to IRIS guidelines was determined. The CBB assay was precise (< 10%) at all urine protein concentrations after excluding outliers from the intra-assay precision assay of high urine protein concentrations. Acceptable accuracy was demonstrated with both LUD and spiking recovery test. Both UP and UPC determined by CBB were significantly higher (P < .0001) than those obtained with PRM, and both a constant and proportional bias were present. Concordance of IRIS substaging was only moderate. The CBB is precise and accurate, but the higher UPC obtained with CBB vs PRM may affect interpretation of the IRIS guidelines.

Proteinuria and lipoprotein lipase activity in Miniature Schnauzer dogs with and without hypertriglyceridemia

Spontaneous hyperlipidemia in rats causes glomerular disease. Idiopathic hypertriglyceridemia (HTG) is prevalent in Miniature Schnauzers, but its relationship with proteinuria is unknown. Decreased activity of major lipid metabolism enzymes, lipoprotein lipase (LPL) and hepatic lipase (HL), may play a role in the cyclic relationship between hyperlipidemia and proteinuria. These enzymes have also not been previously investigated in Miniature Schnauzers. The aims of this study were to determine the relationship between HTG and proteinuria in Miniature Schnauzers and to measure LPL and HL activities in a subset of dogs. Fifty-seven Miniature Schnauzers were recruited (34 with and 23 without HTG). Fasting serum triglyceride concentrations and urine protein-to-creatinine ratios (UPC) were measured in all dogs, and LPL and HL activities were determined in 17 dogs (8 with and 9 without HTG). There was a strong positive correlation between triglyceride concentration and UPC (r = 0.77–0.83, P < 0.001). Proteinuria (UPC ≥ 0.5) was present in 60% of dogs with HTG and absent from all dogs without HTG (P < 0.001). Proteinuric dogs were not azotemic or hypoalbuminemic. Dogs with HTG had a 65% reduction in LPL activity relative to dogs without HTG (P < 0.001); HL activity did not differ. Proteinuria occurs with HTG in Miniature Schnauzers and could be due to lipid-induced glomerular injury. Reduced LPL activity may contribute to the severity of HTG, but further assay validation is required.

Evaluation of the relationship between clinical variables and thromboelastographic findings in dogs with protein-losing nephropathy.

To determine whether hypercoagulability in proteinuric dogs, defined by thromboelastography (TEG), is related to the degree of proteinuria, presence of systemic arterial hypertension, presence of hypoalbuminemia, or reduced antithrombin activity. Prospective study of client-owned dogs. Data collected from each patient included signalment, body weight, urine protein-to-creatinine ratio (UPC), serum albumin concentration, TEG values, noninvasive arterial blood pressure, and AT activity. Hypercoagulability was diagnosed by TEG and odds ratios for other measurements were assessed by univariate logistic regression. Urban referral center and teaching hospital. Seventy-six dogs with protein-losing nephropathy (PLN) based on UPC, diagnosed between Oct 2009 and Oct 2012. None. The prevalence of hypercoagulability was 89%. No statistically significant associations were detected between hypercoagulability and UPC, serum albumin, noninvasive blood pressure, or AT activity (all P > 0.05). The prevalence of thromboembolism was 6.6%. Hypercoagulability was prevalent in dogs with PLN but could not be predicted based upon the presence or degree of proteinuria, systemic arterial hypertension, hypoalbuminemia, or low AT activity. The prevalance of thromboembolism was low in this population with PLN.

Characterization of Proteinuria in Dogue de Bordeaux Dogs, a Breed Predisposed to a Familial Glomerulonephropathy: A Retrospective Study

Dogue de Bordeaux dog has been reported to be predisposed to a familial glomerulonephropathy that displays some morphological modifications reported in focal and segmental glomerulosclerosis. Prevalence of quantitatively abnormal renal proteinuria was recently reported to be 33% in this breed. The nature of the proteinuria was assessed by sodium dodecyl sulfate-agarose gel electrophoresis and determinations of urinary markers (urinary retinol-binding protein, urinary N-acetyl-β-glucosaminidase, urinary albumin and urinary immunoglobulin G) on stored specimens. Diagnostic performances of sodium dodecyl sulfate-agarose gel electrophoresis to identify dogs with elevated urinary biomarkers were assessed. Samples from 102 adult Dogue de Bordeaux dogs (47 non-proteinuric [urine protein-to-creatinine ratio≤0.2], 20 borderline-proteinuric [0.2< urine protein-to-creatinine ratio ≤0.5] and 35 proteinuric dogs [urine protein-to-creatinine ratio >0.5]) were used, of which 2 were suffering from familial glomerulonephropathy. The electrophoretic protein patterns, for all but one proteinuric dog, were indicative of a glomerular origin and, in all dogs, the urinary albumin concentration related to creatinine concentration and the urinary immunoglobulin G concentration related to creatinine concentration were above the upper limit of the reference interval established for the breed. Sensitivity and specificity of sodium dodecyl sulfate-agarose gel electrophoresis identifying dogs with elevated urinary albumin concentration were 94% and 92%, respectively, while diagnostic performance of sodium dodecyl sulfate-agarose gel electrophoresis in detecting dogs with elevated urinary immunoglobulin G concentration yielded sensitivity and specificity of 90% and 74%, respectively. These results suggest that all proteinuric and some borderline-proteinuric Dogue de Bordeaux dogs likely have underlying glomerular lesions and that sodium dodecyl sulfate-agarose gel electrophoresis and urinary markers might be useful to screen dogs with borderline-proteinuria. Additional investigations are warranted to assess if these findings are related to the familial glomerulonephropathy.

The effect of inter-laboratory variability on the protein:creatinine (UPC) ratio in canine urine

Quantification of proteinuria is a fundamental step in staging dogs with chronic kidney disease and in monitoring the course of disease or the efficacy of anti-proteinuric treatments. Analytical precision and accuracy of the proteinuria assessment could be affected by several factors such as biological variability, different operators and quality control materials. The aim of this study was to assess whether inter-laboratory variability could affect the urinary protein to creatinine (UPC) ratio and whether this variability may affect patient classification according to the International Renal Interest Society (IRIS) sub-staging system. The same urine samples were analysed in three different laboratories using different instruments and different reagent brands.The results of the three laboratories were highly correlated to each other although urinary protein (UP), urinary creatinine (UC) and the UPC ratio of one laboratory were found to be significantly higher than those of the other two. No significant differences between the other two laboratories were recorded. The concordance in classifying dogs according to the IRIS guidelines was good if all three proteinuria categories were analysed separately or if borderline proteinuric (BP) dogs were included in the proteinuric group, and very good if BP dogs were merged into the non-proteinuric group. The inter-laboratory variability in UPC ratio measurement was not so great as to impede the identification of proteinuric dogs, but may influence the estimation of the magnitude of proteinuria.

Relationship between urinary Tamm–Horsfall protein excretion and renal function in dogs with naturally occurring renal disease

Tamm-Horsfall protein (THP) is physiologically excreted in urine, but little is known about the role of THP in the diagnosis of renal disease in dogs. The aim of this study was to evaluate to which extent naturally occurring renal disease affects the urinary excretion of THP. Dogs were divided into 5 groups according to plasma creatinine concentration, urinary protein-to-creatinine ratio (UP/UC), and exogenous plasma creatinine clearance (P-ClCr ) rates: Group A (healthy control dogs; n = 8), nonazotemic and nonproteinuric dogs, with P-ClCr rates > 90 mL/min/m(2) ; group B (n = 25), nonazotemic and nonproteinuric dogs with reduced P-ClCr rates (51-89 mL/min/m(2) ); group C (n = 7), nonazotemic but proteinuric dogs with P-ClCr rates 53-98 mL/min/m(2) ; group D (n = 8), azotemic and borderline proteinuric dogs (P-ClCr rates: 22-45 mL/min/m(2) ); and group E (n = 15), azotemic and proteinuric dogs (not tested for P-ClCr ). THP was measured by quantitative Western blot analysis, and the ratio of THP-to-urinary creatinine (THP/UC) was calculated. The THP/UC concentrations were not different among dogs of groups A-D, but were reduced in dogs of group E (P < .001). THP/UC correlated negatively with serum creatinine (P < .01) and UP/UC (P < .01), but was not significantly associated with P-ClCr . Decreased levels of THP/UC were present in moderately to severely azotemic and proteinuric dogs. This suggests tubular injury in these dogs and that THP might be useful as urinary marker to study the pathogenesis of renal disease.

Serum ferritin and paraoxonase-1 in canine leishmaniosis

Ferritin and paraoxonase-1 (PON-1) were measured in dogs experimentally infected by Leishmania infantum (during experimental infection and following treatment) and also in naturally-infected dogs which presented different degrees of proteinuria. Experimentally-infected dogs were monitored for 7 months post-infection, then treated for 3 months with allopurinol, and their response to therapy was followed for 11 additional months. Naturally-infected dogs were staged based on the urine protein/creatinine (UPC) ratio into three groups as follows: group 1 (non-proteinuric; UPC ratio: <0.2), group 2 (borderline proteinuric; UPC ratio: 0.2-0.5) and group 3 (proteinuric; UPC ratio>0.5). An increase in serum ferritin values and a decrease in PON-1 activity were observed 2 months after infection. Both analytes returned to preinfection values following treatment. Significantly higher concentrations of ferritin were observed in dogs classified as either borderline or proteinuric when compared with non-proteinuric dogs whereas serum PON-1 activity was decreased only in proteinuric dogs.

Pathologic Evaluation of Canine Renal Biopsies: Methods for Identifying Features that Differentiate Immune‐Mediated Glomerulonephritides from Other Categories of Glomerular Diseases

Human renal biopsies are routinely evaluated with light microscopy (LM) using a panel of histologic stains, transmission electron microscopy (TEM), and immunofluorescence (IF) microscopy to obtain a diagnosis. In contrast, the pathologic evaluation of glomerular disease in veterinary medicine has relied mostly on LM and was of limited utility. To address this problem, recently established veterinary renal diagnostic centers have adopted methods used in human nephropathology for evaluation of renal biopsies. Three broad categories of disease, which have the greatest implications for clinical management of proteinuric dogs, have been established and include amyloidosis, immune complex-mediated glomerulonephritis (ICGN), and non-ICGN. To demonstrate histopathologic, ultrastructural, and IF findings in renal biopsy specimens that experienced veterinary nephropathologists utilize to make accurate and clinically useful diagnoses in dogs with proteinuric glomerular disease and to provide guidelines for the proper evaluation of renal biopsies. Renal biopsy specimens were routinely examined by LM, IF, and TEM. Samples were reviewed by members of the World Small Animal Veterinary Association Renal Standardization Study Group to identify lesions that were diagnostic for, or suggestive of, the presence of immune complexes (IC) or amyloidosis in all modalities. Ten guidelines for renal biopsy evaluation were formulated. Each method of investigation contributed important findings that were integrated to make an accurate final morphological diagnosis. The guidelines were validated by an independent group of veterinary pathologists. Routine evaluation of renal biopsies with LM, TEM, and IF is feasible and necessary for making accurate, morphologic diagnoses that can be used to guide clinical management of dogs with glomerular disease.

Variation of Proteinuria in Dogs with Leishmaniasis Treated with Meglumine Antimoniate and Allopurinol: A Retrospective Study

A retrospective study was performed using 53 client owned dogs with leishmaniasis to determine whether the degree of proteinuria, evaluated by the urine protein/creatinine ratio (UP/C), changes following treatment with meglumine antimoniate and allopurinol. Medical records of dogs with leishmaniasis in clinical stage C (according to the Canine Leishmaniasis Working Group staging system) and either proteinuric or borderline proteinuric (according to the International Renal Interest Society [IRIS] staging system) were reviewed. All dogs were treated with meglumine antimoniate and allopurinol for 4-8 wk. After treatment, UP/C, total protein, and total globulin significantly decreased and albumin and the albumin/globulin ratio (A/G) increased. After treatment, 7 of the 53 dogs (13.4%) became nonproteinuric following either a proteinuric or borderline proteinuric stage. Moreover, 12 of the 53 proteinuric dogs (22.6%) changed their stage to borderline proteinuric. The antileishmaniasis treatment with meglumine antimoniate in combination with allopurinol in dogs significantly reduced the degree of proteinuria in a short period of time. The results of the current study may be useful to the veterinary practitioner in the clinical management of canine leishmaniasis (CanL) in dogs with proteinuric chronic kidney disease.