Urinary clusterin and cystatin B as biomarkers of tubular injury in dogs following envenomation by the European adder.

Diagnosing acute kidney injury remains a challenge since the established renal biomarkers, serum creatinine (sCr) and symmetric dimethylarginine (SDMA) reflect glomerular function and not tubular injury. Sensitive tubular markers such as urinary clusterin (uClust) and cystatin B (uCysB) have been proposed to detect AKI at an earlier stage. Since envenomation by the European adder (Vipera berus berus) could serve as a spontaneous disease model of AKI we investigated these new biomarkers in affected dogs. Concentrations of uClust and uCysB as well as sCr and SDMA were analyzed retrospectively in stored samples from 26 dogs with snake envenomation and 13 healthy controls. Higher concentrations of uClust (P < 0.012) and uCysB (P < 0.001) were observed in the snake-envenomed group. Normalization of uClust and uCysB to urinary creatinine did not alter the results. No differences were observed in sCr and SDMA between the snake-envenomed group and the healthy control group. Spearman rank correlation analysis revealed a strong association of uClust with uCysB in the snake-envenomed dogs (r = 0.75 P < 0.001) but not in the healthy controls. The high percentage of snake-envenomed dogs with increased uClust and uCysB concentrations in the absence of increased sCr and SDMA suggests renal tubular injury in the affected dogs. Larger prospective case-controlled studies are warranted to evaluate the clinical utility and prognostic value of these biomarkers.

Traction suture modification to tongue-in-groove caudal septoplasty.

Caudal septal deviation leads to unfavorable esthetic as well as functional effects on the nasal airway. A modification to the tongue-in-groove (TIG) technique to correct these caudal septal deformities is described. With placement of a temporary suspension suture to the caudal septum, manual traction is applied, assuring that the caudal septum remains in the midline position while it is being secured with multiple through-and-through, trans-columellar and trans-septal sutures. From 2003 to 2016, 148 patients underwent endonasal septoplasty using this modified technique, with excellent functional and cosmetic outcomes and a revision rate of 1.4%. This modified TIG technique replaces the periosteal suture that secures the caudal septum to the midline nasal crest in the original TIG technique. This simplifies the procedure and minimizes the risk of securing the caudal septum off-midline when used in endonasal septoplasty.

Long-term increases in renal sympathetic nerve activity and hypertension.

1. Essential hypertensive patients have been characterized by increased sympathetic nerve activity, increased peripheral vascular tone, decreased plasma volume and normal cardiac output when compared with normotensive subjects. Bilateral renal denervation reduces the magnitude or delays the onset of the blood pressure response in numerous models of experimental hypertension regardless of the aetiology of the elevation in arterial pressure. 2. Using a servocontrolled intrarenal infusion system, we have elevated intrarenal noradrenaline concentration via intermittent renal artery infusion without decreasing renal blood flow as a method of simulating selective elevation of renal sympathetic outflow. 3. Chronic intrarenal adrenergic stimulation increased arterial pressure within 24 h and this hypertension persisted for 28 consecutive days. The elevated arterial pressure was not associated with sustained increases in plasma renin activity, aldosterone, circulating catecholamines, arginine vasopressin or significant renal vasoconstriction. Urinary sodium excretion was chronically elevated and the dogs remained in negative sodium balance for the duration of the intrarenal noradrenaline infusion. 4. After 2 weeks of elevated intrarenal neurotransmitter coupled with hypertension, renal vascular reactivity to further adrenergic stimulation was significantly increased because the hypertension was maintained during continual reductions in the daily dosage of neurotransmitter allowed to be infused by the servocontroller. After only 28 days of noradrenaline infusion, renal vascular hypertrophy developed in vessels from 150-300 microns. 5. We conclude that selective and intermittent increases in intrarenal adrenergic neurotransmitter are sufficient to elicit chronic hypertension in the absence of volume expansion. This intrarenal neuroadrenergic hypertension is closely associated with the haemodynamic parameters which characterize a major subset of human essential hypertensives.