The Urinary System1

Severe glomerular fibrin thrombosis in a dog

Here, we present a case of severe glomerular fibrin thrombosis in a dog with lymphoma. A 3-year-old neutered male Chihuahua presented with acute kidney injury, hypoalbuminemia, and transudate ascites. The dog showed symmetric enlargement of the spleen, which was diagnosed as B-cell lymphoma based on cytology and polymerase chain reaction tests. The dog died after intensive care, and the kidneys were removed for histopathological examination. Light microscopy, immunofluorescence, and electron microscopy analyses were performed for renal pathology; however, the findings did not support the evidence of protein-losing nephropathy. Instead, the endocapillary accumulation of fibrin thrombi was prominent in most glomeruli. A diagnosis of severe glomerular fibrin thrombosis was established, and hypoalbuminemia was considered the underlying cause of kidney damage.

Ultrasound, CT, and MR Imaging for Evaluation of Cystic Renal Masses

Cystic renal masses are often encountered during abdominal imaging. Although most of them are benign simple cysts, some cystic masses have malignant characteristics. The Bosniak classification system provides a useful way to classify cystic masses. The Bosniak classification is based on the results of a well-established computed tomography protocol. Over the past 30 years, the classification system has been refined and improved. This paper reviews the literature on this topic and compares the advantages and disadvantages of different screening and classification methods. Patients will benefit from multimodal diagnosis for lesions that are difficult to classify after a single examination.

Association of ultrasonographic features with histologic findings in 71 dogs with protein-losing nephropathy (2008-2018)

OBJECTIVE

To determine whether ultrasonographic features in dogs with protein-losing nephropathy (PLN) were associated with renal biopsy findings and compare corticomedullary ratios between dogs with PLN versus non-renal disease.

ANIMALS

71 dogs with PLN and 33 dogs without renal disease.

PROCEDURES

Medical records and archived ultrasonographic images for dogs with PLN that underwent renal biopsy between 2008 and 2018 were reviewed. Corticomedullary ratios were measured.

RESULTS

In dogs with PLN, median serum creatinine and BUN concentrations and urine-protein-to-creatinine-ratio prior to renal biopsy were 3.4 mg/dL (interquartile range [IQR], 1.2 to 5.3 mg/dL), 80 mg/dL (IQR, 28 to 105 mg/dL), and 11.4 (IQR, 6.4 to 18.3), respectively. Histologic abnormalities within the tubulointerstitial space were associated with cortical echogenicity. Gastric wall thickness > 5 mm was associated with a histologic diagnosis of acute glomerular disease. Dogs with immune complex-mediated glomerular disease were more likely to have abnormal gastric mural architecture. Other ultrasonographic features of the kidneys, liver, and stomach and the presence of ascites did not help to differentiate immune complex-mediated from non-immune complex-mediated glomerular disease, acute from chronic disease, or amyloid from non-amyloid disease or distinguish whether tubulointerstitial disease was present or absent. Median left corticomedullary ratio for 66 dogs with PLN (1.2) was significantly higher than that for the 33 dogs without renal disease (1.0).

Clinical Relevance

Ultrasonographic features were poorly associated with specific pathological disorders in dogs with PLN. In this study, the corticomedullary ratio was higher in dogs with PLN, indicating the presence of cortical thickening, but the clinical relevance is unknown.

Drugs Dosing in Geriatric Patients Depending on Kidney Function Estimated by MDRD and Cockroft-Gault Formulas

INTRODUCTION

According to the current data, regardless of the method used to estimate GFR, the differences between the obtained results should be insignificant and do not imply therapeutic decisions. The aim of this study was to analyze and compare the eGFR results with the estimated creatinine clearance score calculated according to the Cockroft-Gault equation, and to assess the significance of the difference between these two results.

SAMPLE AND METHODS

A study group was constituted of 115 patients, of whom 76 were women and 39 men at the age range of 55-93 years, with a median of 79 years. The study analyzed differences in the assessment of kidney function by comparing the results of eGFR assessed by MDRD method obtained from the laboratory with the calculated values of creatinine clearance using the Cockroft-Gault formula, and examining the correlation between the difference D = eGFR -eClCr and BMI and body surface.

RESULTS

In the entire group of patients (N = 115), the significant statistical difference was found between eGFR and eClCr. In the subgroup of patients (N = 45) with the lower baseline eGFR <60, there was no significant difference between eGFR and eClCr, while in the subgroup of patients with baseline eGFR ≥60 (N = 75), there was a significant difference between eGFR and eClCr. The study showed that based on the estimated GFR using both methods (C-G and MDRD), 29.2% and 32.4% of patients, respectively, were incorrectly assigned to given stage of chronic kidney disease.

CONCLUSION

Proper assessment of kidney function is very important in order to properly drugs dosing, especially to adjust the doses of drugs metabolized by the kidneys in order to avoid or minimize their nephrotoxic effects.

Post-mortem assessment of vimentin expression as a biomarker for renal tubular regeneration following acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is a common cause of morbidity and mortality. It mainly targets the renal tubular epithelium with pathological changes, referred to as acute tubular injury. The latter is followed by a regenerative response that is difficult to visualize on routine hematoxylin and eosin (H&E) stains. In this study, we examined the regenerative capacity of renal tubules by correlating vimentin (VIM) immunohistochemical (IHC) expression and pathological findings of AKI and renal tubular regeneration (RTR) on H&E.

METHODS

We reviewed 23 autopsies performed in the clinical setting of AKI and RTR. VIM expression was scored in the renal cortical tubular epithelium using a statistical cutoff ≥ 3% for high expression and < 3% for low expression.

RESULTS

Of the 23 kidney tissues examined, seven (30.4%) had low VIM expression, and 16 (69.6%) had high VIM expression. Kidney tissues with evidence of AKI and RTR had significantly higher VIM expression. Renal peritubular microenvironment features showing regenerative changes on H&E were associated with high VIM expression. In the univariate model, kidney tissues with RTR were 18-fold more likely to have high VIM expression.

CONCLUSIONS

In conclusion, our findings suggest that VIM could serve as an IHC marker for RTR following AKI. However, correlation with H&E findings remains critical to excluding chronic tubular damage. Collectively, our preliminary results pave the way for future studies including a larger sample size to validate the use of VIM as a reliable biomarker for RTR.

High Expression of SLC16A1 as a Biomarker to Predict Poor Prognosis of Urological Cancers

Objective

Tumor metabolism has always been the focus of cancer research. SLC16A1, as a key factor in catalysis of monocarboxylate transport across the plasma membrane, has been found to be associated with the occurrence and metastasis of a variety of cancers, but its prognostic significance and mechanism in different tumors are still unclear.

Methods

Based on the gene expression matrix and clinical information of human cancer tissues acquired from TCGA and GTEX databases, the differential expression of SLC16A1 in different tumors and normal tissues was analyzed. To confirm the association between its expression, the mutation of MMRS gene, and the expression level of DNMTs. Univariate Cox regression was applied to analyze the association between SLC16A1 expression and patient prognosis. The effect of SLC16A1 expression on patient survival was examined by Kaplan Meier analysis. GSEA was used to identify related signaling pathways.

Results

The expression of SLC16A1 was differentially expressed in most tumors, especially in the urinary tract where it is commonly highly expressed, and differential expression of SLC16A1 in different clinical stages. SLC16A1 expression was significantly positively correlated with MMRS gene mutation and DNMTS expression. Moreover, high SLC16A1 expression was associated with poorer overall survival (OS) and progression-free survival (PFS) in urological cancers. In particular, the results of the enrichment analysis showed that SLC16A1 was associated with processes such as cell adhesion and many signaling pathways affecting cell cycle were significantly enriched in the group with high-expressed SLC16A1.

Conclusion

SLC16A1 expression was upregulated in urological cancer. SLC16A1 may promote tumor development by regulating the epigenetic process of urological cancer and demonstrated a great potential as a prognostic biomarker of urological cancer patients.

Parasitic encephalitis caused by Stephanurus dentatus in a pig in Brazil

A pig was in left lateral recumbency with limb spasticity, accentuated prostration, and strabismus, and was euthanized. During autopsy, yellowing of the leptomeninges at the ventral pons to medulla oblongata was noted. In the cerebellar peduncles, there was a focally extensive black-to-yellow area at the level of the vestibular nuclei. Histologic examination revealed a cross-section of a nematode larva, consistent with Stephanurus dentatus, bordered by edema and marked infiltration of mononuclear cells, plasma cells, and a few eosinophils. Vacuolation of the neuropil, with rare gitter cells and axonal spheroids, was also observed. We diagnosed parasitic encephalitis caused by S. dentatus migration based on the pathology findings and characterization of the parasite.

EARLY-ONSET LEUKOENCEPHALOMYELOPATHY AND POLYNEUROPATHY IN EASTERN QUOLLS (DASYURUS VIVERRINUS) IN THE EUROPEAN CAPTIVE POPULATION

Leukoencephalomyelopathy (LEM) is suggested to be an age-related degenerative condition in geriatric Eastern quolls (Dasyurus viverrinus), manifesting in animals greater than 3.5 yr of age. This case series describes four LEM cases from two zoologic collections; three in nongeriatric animals, with one only 1 yr of age, and details advanced diagnostic investigation, including magnetic resonance imaging, cerebrospinal fluid analysis, and electrodiagnostic studies, not previously reported in Eastern quolls. Animals presented clinically with forelimb proprioceptive deficits and hindlimb and lumbar muscle hypotrophy, which were not noted in previous reports, in addition to hindlimb ataxia. Blindness and emaciation, which have been reported previously, were not seen. Disease progression was variable, and time from first clinical signs to euthanasia ranged from 46 days to over 2 yr. Histopathologic findings in the central nervous system were typical of those in previous LEM cases; concomitant polyneuropathy was observed in two quolls. Our findings suggest that age-related degeneration may not be the only cause of LEM in Eastern quolls. Because all quolls were related, a familial component cannot be excluded. LEM should be further investigated for its potential impact on future captive breeding programs, and our findings suggest that daily quality-of-life assessment should guide euthanasia of affected animals.

Porcine Babesiosis Caused by Babesia sp. Suis in a Pot-Bellied Pig in South Africa

Babesiosis is a worldwide, tick-borne disease of economic importance in livestock caused by Babesia spp., which are hemoparasitic piroplasms that target the host erythrocytes. Cattle, dogs, small ruminants, and wild ruminants are the species most commonly affected, while in cats, horses, and pigs, it is less frequently reported. Although babesiosis has been observed worldwide, porcine babesiosis remains an uncommon disease with a very limited number of cases reported. Here, we describe a case in a 12-year old pot-bellied pig from South Africa that died after a history of anorexia and reluctance to rise for 2 days. A complete necropsy, blood smear cytology, reverse line blot (RLB) hybridization and 18S rRNA sequencing were performed. Numerous Babesia spp. hemoparasites and a moderate regenerative anemia were identified on blood smear, and a urine dipstick test yielded 4+ heme. Diffuse icterus and splenomegaly were observed upon gross examination. Histopathology revealed hemoglobin casts within renal tubules and collecting ducts, pulmonary edema, splenic congestion, and intrahepatic cholestasis. BLASTN homology of the 18SrRNA sequence revealed a 100% identity to the published sequence of Babesia sp. Suis isolated from pigs in Italy. This case of babesiosis in a pig highlights the clinical manifestations and gross and pathological findings of porcine babesiosis.

Can distinction between the renal cortex and outer medulla on ultrasonography predict estimated glomerular filtration rate in canine chronic kidney diseases?

Background

Quantitative evaluation of renal cortical echogenicity (RCE) has been tried and developed in human and veterinary medicine.

Objectives

The objective of this study was to propose a method for evaluating RCE quantitatively and intuitively, and to determine associations between ultrasonographic renal structural distinction and estimated glomerular filtration rate (eGFR) in canine chronic kidney disease (CKD).

Methods

Data were collected on 63 dogs, including 27 with normal kidney function and 36 CKD patients. Symmetric dimethylarginine and creatinine concentrations were measured for calculating eGFR. RCE was evaluated as 3 grades on ultrasonography images according to the distinction between the renal cortex and outer medulla. The RCE grade of each kidney was measured.

Results

There was a significant difference in eGFR between the group normal and CKD (p < 0.001). As mean of RCE grades (the mean values of each right and left kidney's RCE grade) increases, the proportion of group CKD among the patients in each grade increases (p < 0.001). Also, severity of RCE (classified as "high" if any right or left kidney evaluated as RCE grade 3, "low" otherwise) and eGFR is good indicator for predicting group CKD (p < 0.001).

Conclusions

The degree of distinction between the renal cortex and the outer medulla is closely related to renal function including eGFR and the RCE grade defined in this study can be used as a method of objectively evaluating RCE.

Comparison of renal lesions in cats and dogs using pathomorphological and ımmunohistochemical methods

We investigated the pathogenesis of chronic renal fibrosis in cats and dogs using immunohistochemistry. We used the avidin-biotin complex peroxidase (ABC-P) method with antibodies against transforming growth factor-β1, cytokeratin, E-cadherin, S100A4, alpha-smooth muscle actin, vimentin and nestin to determine whether tubule epithelial cells had undergone epithelial-mesenchymal transformation (EMT) that resulted in loss of epithelial cells and an increased number of mesenchymal cells. Although nephrosis was more common in dogs, nephritis was more common in cats; these pathologies developed in both kidneys. We found that EMT participated in the pathogenesis of renal fibrosis in both dogs and cats.