Avaliação Semiológica e Diagnóstico em Pequenos Animais - Aula - 14.3

Summary

This video provides an in-depth exploration of various renal system pathologies, including hydronephrosis, pyelonephritis, kidney stones, mineralizations, renal cysts, and end-stage renal disease. The lecturer explains how obstructions, like stones or tumors, lead to hydronephrosis, causing kidney damage. Additionally, it covers pyelonephritis and its effects on kidney morphology, the diagnostic role of ultrasound, and imaging techniques like contrast radiography and tomography. The importance of differentiating between conditions such as cystitis, neoplasia, and infections is emphasized, alongside a focus on diagnostic tools and surgical considerations for various renal disorders.

Takeaways

• 😀 Hidronephrosis occurs when an obstruction in the urinary tract causes urine to accumulate in the kidneys, leading to kidney enlargement and potential loss of cortical tissue.
• 😀 Pyelonephritis is a kidney infection characterized by irregularities in the renal capsule and increased echogenicity due to the presence of inflammatory tissue.
• 😀 Kidney stones (calculi) create acoustic shadowing in ultrasound images, allowing for easy identification. Their size and location can indicate whether they may obstruct the urinary tract.
• 😀 Renal mineralizations refer to deposits of various minerals in the kidneys, which are typically hyperechoic and may cause difficulties in distinguishing from kidney stones.
• 😀 Renal cysts are commonly seen in veterinary medicine, particularly in cats. They appear as circular anechoic structures in the kidneys and should be differentiated from abscesses or neoplasms.
• 😀 End-stage kidney disease results from the progression of pyelonephritis, leading to severe loss of the cortical-medullary distinction and poor kidney morphology.
• 😀 Ureter dilation is often a result of obstructions in the urinary tract, and its presence can be identified via ultrasound or more commonly, radiography.
• 😀 Contrast-enhanced radiography (urografia excretora) is useful for evaluating the renal system, as it allows for better visualization of the ureters and any obstructions.
• 😀 Cystitis involves inflammation of the bladder, visible on ultrasound as anechoic content surrounded by a trilaminar, hyperechoic bladder wall. It may resemble a neoplastic process in some cases.
• 😀 When examining ultrasound images, the renal medulla and cortex should be easily distinguishable in healthy kidneys. Loss of this distinction indicates serious kidney dysfunction or disease.

Q & A

What is hydronephrosis and how does it occur?

Hydronephrosis is a condition where there is an obstruction in the urinary tract, often due to a kidney stone or tumor. This blockage causes urine to accumulate in the kidneys, leading to their expansion. Over time, this can cause significant damage to the renal structures, including the cortical region.

How can an obstruction lead to hydronephrosis?

An obstruction, such as a kidney stone or tumor, prevents urine from flowing normally from the kidneys to the bladder. This causes urine to back up, accumulating in the kidneys, expanding the renal pelvis, and eventually damaging the kidney's structure.

What is the significance of bilateral hydronephrosis?

Bilateral hydronephrosis means that both kidneys are affected by obstruction, leading to a dilation of both renal pelves and ureters. This condition often indicates a severe obstruction in the lower urinary tract, requiring urgent medical intervention.

What are the key signs of pyelonephritis in ultrasound imaging?

In ultrasound imaging, pyelonephritis is characterized by irregularities in the renal capsule, increased echogenicity due to inflammatory tissue, and a loss of distinct cortical-medullary boundaries. This indicates infection or inflammation in the kidneys.

How do kidney stones appear in ultrasound images?

Kidney stones appear as echogenic (bright) areas in ultrasound images, often accompanied by an acoustic shadow. This shadow is caused by the high density of the stone, which blocks the sound waves, creating a dark area behind the stone.

What is the difference between calcification and mineralization in the kidneys?

Calcification refers to the deposition of calcium salts in kidney tissue, whereas mineralization refers to the deposition of various minerals, not necessarily calcium. Mineralizations can appear in imaging as hyperechoic areas but do not always cause acoustic shadows like calcifications.

What are renal cysts, and how are they identified in imaging?

Renal cysts are common, fluid-filled sacs that can appear as anechoic (dark) areas in ultrasound images. These cysts are typically round or oval and may be seen throughout the kidneys. They need to be differentiated from abscesses or tumors.

What are the common causes of terminal renal disease?

Terminal renal disease is often a result of chronic kidney conditions, such as pyelonephritis, that have progressed to a stage where the kidneys lose their function. This stage is characterized by the complete loss of the cortical-medullary architecture, making the kidneys unable to perform their filtering role.

How can ultrasound help in diagnosing renal issues?

Ultrasound is particularly useful in diagnosing hydronephrosis, kidney stones, pyelonephritis, and cysts. It can provide images of the kidneys, ureters, and bladder, helping to identify obstructions, inflammation, or structural changes.

What role does contrast-enhanced radiography play in evaluating the renal system?

Contrast-enhanced radiography, such as urograms, is used to visualize the kidneys and ureters more clearly. A contrast dye is injected into the bloodstream, which is filtered by the kidneys and can highlight obstructions or other abnormalities in the renal system during the imaging process.