Ren dexter
The right kidney is heart-shaped and sits under the last 2-3 ribs, more cranially than the left kidney. It is closely associated with the liver and cecum. Each kidney filters approximately 1-2 liters of blood per minute and produces 5-15 liters of urine daily. Equine urine is normally turbid and mucoid due to calcium carbonate crystals; this is normal and should not be mistaken for infection. The right kidney is less mobile than the left because of its association with the liver.
Renal disease can present with changes in urine production, azotemia, or systemic illness. The normal turbidity of equine urine is important to recognize so it is not misinterpreted as pathologic. Right kidney problems can be associated with liver or cecal issues because of anatomical proximity. Diagnosis uses bloodwork, urinalysis, and ultrasound.
## Overview Nephrolithiasis is the formation of stones, usually calcium carbonate, within the kidney. It is less common than bladder stones in horses. Signs include recurrent colic, blood in the urin
## Overview Acute renal failure (also called acute kidney injury when milder) is a sudden decline in kidney function that reduces the kidneys’ ability to filter waste, regulate fluid and electrolytes
## Overview Chronic kidney disease is irreversible, progressive loss of renal function lasting more than three months. It is uncommon in horses. The most frequent presenting signs are weight loss and
## Overview Pyelonephritis is bacterial infection of the kidney, usually ascending from the bladder. Signs include fever, painful or frequent urination, cloudy or foul-smelling urine, weight loss, an
Changes in urine volume, color, or consistency, or systemic signs such as weight loss or lethargy, should be evaluated. Normal equine urine is often cloudy; this is not always a sign of infection.
## Overview Nephrolithiasis is the formation of stones, usually calcium carbonate, within the kidney. It is less common than bladder stones in horses. Signs include recurrent colic, blood in the urine, and weight loss. Ultrasound detects the stones. ## Causes Mineral precipitation in the kidney, sometimes related to infection or metabolic factors. ## Diagnosis Ultrasound of the kidneys, urinalysis showing blood or crystals, and clinical signs. ## Treatment Surgical removal is difficult. Medical management of pain and any infection. Some stones are monitored if asymptomatic. Prognosis is guarded for symptomatic cases. ## Recovery and Prognosis Guarded. Complete resolution is uncommon. ## Prevention None proven. Signs include: recurrent colic; blood in urine; weight loss; stones visible on ultrasound
## Overview Acute renal failure (also called acute kidney injury when milder) is a sudden decline in kidney function that reduces the kidneys’ ability to filter waste, regulate fluid and electrolytes, and maintain acid-base balance. In horses it is most often secondary to severe systemic illness (hemodynamic causes) or exposure to nephrotoxic drugs or pigments. Horses have substantial renal reserve, so clinical signs may appear only after significant damage has already occurred. Early recognition and aggressive fluid therapy improve the chance of recovery. ## Causes The most common causes are reduced renal blood flow from dehydration, hypovolemia, endotoxemia, or shock, and direct nephrotoxicity from aminoglycoside antibiotics, nonsteroidal anti-inflammatory drugs, oxytetracycline, bisphosphonates, or myoglobin/hemoglobin. Leptospira species are the most frequent infectious cause. Prolonged prerenal azotemia can progress to intrinsic acute tubular necrosis. ## Diagnosis History of recent illness or drug exposure, combined with azotemia (elevated creatinine and blood urea nitrogen), is suggestive. Urinalysis may show casts, proteinuria, or isosthenuria. Ultrasound can reveal enlarged kidneys with increased echogenicity. Fractional excretion of electrolytes and response to fluid therapy help distinguish prerenal from intrinsic renal failure. Renal biopsy is rarely performed. ## Treatment The cornerstone is intravenous fluid therapy to restore circulating volume, blood pressure, and renal perfusion, plus elimination of any nephrotoxic agents and treatment of the underlying disease. Electrolyte and acid-base abnormalities are corrected. Diuretics such as furosemide are sometimes used if oliguria persists after volume restoration, but they are not consistently effective. Supportive care addresses secondary complications such as laminitis or thrombophlebitis. ## Recovery and Prognosis Horses with polyuric acute renal failure that respond quickly to fluids often have a good prognosis. Oliguric or anuric cases carry a guarded to poor prognosis. Duration of renal failure before treatment is a major determinant of outcome. Many horses that survive the acute phase regain sufficient function for a normal quality of life, although some develop chronic kidney disease. ## Prevention Avoid unnecessary or prolonged use of nephrotoxic drugs, maintain hydration during illness or transport, and monitor renal values in critically ill horses. Prompt treatment of endotoxemia and colic reduces risk. Signs include: depression; reduced appetite; oliguria or polyuria; elevated heart rate; dehydration; edema in some cases; azotemia on bloodwork
## Overview Chronic kidney disease is irreversible, progressive loss of renal function lasting more than three months. It is uncommon in horses. The most frequent presenting signs are weight loss and polyuria/polydipsia. Many horses remain stable for months to years if creatinine stays moderately elevated. ## Causes Often undetermined by the time of diagnosis. Congenital malformations, previous acute kidney injury, and chronic interstitial nephritis are among the recognized causes. ## Diagnosis Persistent azotemia, inappropriate urine concentration, and compatible clinical signs. Ultrasound and biopsy can further characterize the kidneys. Staging systems analogous to small-animal International Renal Interest Society guidelines have been proposed. ## Treatment Supportive care: adequate calories, controlled protein and mineral intake, free access to water, and management of complications. No specific cure exists. ## Recovery and Prognosis The disease is progressive but often slow. Horses with creatinine remaining below approximately 4 to 5 mg/dL frequently maintain acceptable quality of life for extended periods. ## Prevention Prompt treatment of acute kidney insults and avoidance of nephrotoxic drugs when possible. Signs include: weight loss; increased thirst and urination; poor appetite; ventral edema in some cases; elevated creatinine and urea
## Overview Pyelonephritis is bacterial infection of the kidney, usually ascending from the bladder. Signs include fever, painful or frequent urination, cloudy or foul-smelling urine, weight loss, and pain on rectal palpation of the kidney (especially the left, which is more accessible). It is less common than simple cystitis. ## Causes Ascending urinary-tract infection. ## Diagnosis Urinalysis, culture, ultrasound of the kidneys, and bloodwork. ## Treatment Prolonged antibiotics based on culture and sensitivity. Address any underlying cause of urinary stasis. ## Recovery and Prognosis Fair to good if treated early. Chronic cases can lead to renal scarring. ## Prevention Prompt treatment of lower urinary-tract infections. Signs include: fever; painful urination; cloudy or foul urine; weight loss; pain on rectal palpation of the kidney
Renal disease can present with changes in urine production, azotemia, or systemic illness. The normal turbidity of equine urine is important to recognize so it is not misinterpreted as pathologic. Right kidney problems can be associated with liver or cecal issues because of anatomical proximity. Diagnosis uses bloodwork, urinalysis, and ultrasound.
Changes in urine volume, color, or consistency, or systemic signs such as weight loss or lethargy, should be evaluated. Normal equine urine is often cloudy; this is not always a sign of infection.
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