Placement of a subcutaneous ureteral bypass in a Miniature Pinscher with presumed xanthine urolithiasis as a result of allopurinol treatment.

INTRODUCTION: This case report describes the long-term success of a subcutaneous ureteral bypass device in a dog for treatment of a ureteral obstruction. The suspected xanthine urolithiasis was secondary to treatment with allopurinol for leishmaniasis. The dog presented initially with lethargy, anuria and abdominal pain. Mild azotemia was found on biochemical analysis and abdominal ultrasound revealed bilateral ureteral obstruction. A subcutaneous ureteral bypass was subsequently placed using a standard surgical technique. The dog recovered uneventfully and the azotemia resolved within days. Follow-up examinations were performed every trimester for over three years and no complications like obstruction of the bypass tubes, urinary tract infection or azotemia were recognized during this follow-up period. Allopurinol was replaced with domperidone as long-term treatment against Leishmaniasis which resulted in a mild increase of the leishmania serum antibody titer. The subcutaneous ureteral bypass placement was successful and safe in this dog and is a valuable alternative in cases of ureteral obstruction also in dogs.

INTRODUCTION: Ce rapport de cas décrit le succès à long terme d'une dérivation urétérale sous-cutanée chez un chien pour le traitement d'une obstruction urétérale. L'urolithiase xanthique suspectée était secondaire à un traitement à l'allopurinol contre la leishmaniose. Le chien a d'abord présenté une léthargie, une anurie et des douleurs abdominales. L'analyse biochimique a révélé une légère azotémie et l'échographie abdominale a révélé une obstruction urétérale bilatérale. Une dérivation urétérale sous-cutanée a été mise en place selon une technique chirurgicale standard. Le chien s'est rétabli sans incident et l'azotémie a disparu en quelques jours. Des examens de suivi ont été effectués tous les trimestres pendant plus de trois ans et aucune complication telle qu'une obstruction du tube de dérivation, une infection urinaire ou une azotémie n'a été constatée au cours de cette période de suivi. L'allopurinol a été remplacé par de la dompéridone dans le cadre d'un traitement à long terme contre la leishmaniose, ce qui a entraîné une légère augmentation du titre des anticorps sériques contre la leishmaniose. La mise en place d'une dérivation urétérale sous-cutanée s'est avérée efficace et sûre chez ce chien et constitue une alternative intéressante en cas d'obstruction urétérale, y compris chez les chiens.

Diagnostic value of two commercial chromatographic "patient-side" tests in the diagnosis of acute canine leptospirosis.

OBJECTIVES: To determine the diagnostic performance of two patient-side tests (RDT-1: Test-it™ and RDT-2 Witness®Lepto) in the early diagnosis of canine leptospirosis. METHODS: Retrospective study of 108 dogs with leptospirosis and 53 controls. Leptospirosis was diagnosed based on compatible clinical and clinicopathologic signs and either a single microscopic agglutination test titre_ >800 (n=49), seroconversion (n=53), positive urine real time PCR (RT-PCR) (n=1), evidence of spirochaetes in silver-stained tissues (n=1) or a combination of these (n=4). Leptospirosis was excluded in dogs with a convincing alternative diagnosis and single microscopic agglutination testing titres _<200 (n=46) or lack of seroconversion (n=7). Indices of diagnostic accuracy of the rapid diagnostic tests were calculated by comparing admission rapid diagnostic test results to the final disease status. RESULTS: Rapid diagnostic test-1 was performed in 118 dogs, rapid diagnostic test-2 in 69 dogs and both tests in 26 dogs. Weak positive results occurred frequently representing 22·6% (rapid diagnostic test-1) and 32·3% (rapid diagnostic test-2) of all positive tests in dogs with leptospirosis. If weak positive rapid diagnostic tests were considered positive, rapid diagnostic test-1 and rapid diagnostic test-2 had sensitivities of 82 and 76%, specificities of 91 and 100%, positive predictive values of 94% and 100% and negative predictive values of 73% and 74%, respectively. There were some technical problems with rapid diagnostic test-1. CLINICAL SIGNIFICANCE: The diagnostic performance of the rapid diagnostic tests is similar to that reported for the microscopic agglutination test. Both can support a diagnosis of leptospirosis with high specificity but leptospirosis cannot be excluded based on a negative admission test result. Both RDTs are useful in conjunction with other confirmatory tests.

Biphasic plasticity of dendritic fields in layer V motor neurons in response to motor learning.

Motor learning is associated with plastic reorganization of neural networks in primary motor cortex (M1) that advances through stages. An initial increment in spine formation is followed by pruning and maturation one week after training ended. A similar biphasic course was described for the size of the forelimb representation in M1. This study investigates the evolution of the dendritic architecture in response to motor skill training using Golgy-Cox silver impregnation in rat M1. After learning of a unilateral forelimb-reaching task to plateau performance, an increase in dendritic length of layer V pyramidal neurons (i.e. motor neurons) was observed that peaked one month after training ended. This increment in dendritic length reflected an expansion of the distal dendritic compartment. After one month dendritic arborization shrinks even though animals retain task performance. This pattern of evolution was observed for apical and basal dendrites alike - although the increase in dendritic length occurs faster in basal than in apical dendrites. Dendritic plasticity in response to motor training follows a biphasic course with initial expansion and subsequent shrinkage. This evolution takes fourth as long as the biphasic reorganization of spines or motor representations.