Question

Louis, a 60-year-old male, has not been feeling himself lately. He has been drowsy and fatigued. He becomes short of breath walking from one room to the next. On a recent visit, his daughter noticed that he seemed to be scratching a lot. His legs, ankles, and feet were extremely swollen and his shortness of breath was becoming worse. He began to complain of chest pain and was immediately taken to the emergency room. A review of Louis’ medical history revealed that he was currently being treated for a urinary tract infection. His infection was resistant to the antibiotics that he was initially treated with. He began treatment with gentamicin 5 days ago. Physical examination confirmed the observations of Louis’ daughter. A urinary catheter was placed in Louis’ bladder in order to determine urine output. A sample was sent to the laboratory for analysis. His urine analysis showed cloudy, dark urine. Casts were seen. A diagnosis of acute renal failure due to nephrotoxic acute tubular necrosis (ATN) was made.

Explain the pathophysiology associated with nephrotoxic acute tubular necrosis.

Answer 1

Acute renal failure is a reversible condition if the causes are treated correctly.

Acute renal failure may leads to fluid and electrolyte imbalances and cause failure in the excretion of nitrogenous wastes .

Nephro toxic acute tubular necrosis is the damage of the kidney tubules as a result of exposure to toxins.

It may result in acute renal failure.

causes.

- Urinary tract infection.

- use of aminoglycosides like gentamycin.Gentamycin is a nephro toxic agent.

pathophysiology .

1. Due to use of aminoglycosides like gentamycin

2 . which leads to Intra tubular obstructions .

3 .Due to Intra tubular obstructions decreased urine flow and abnormal reabsorption of filtrates occurs.

4.Due to this changes in glomerular permeability glomerular filtration rate decreases.

5 .leads to parenchymal damage to the glomeruli or kidney tubules .

6.Results in acute tubular necrosis.

The use of aminoglycosides like gentamycin.Gentamycin is a nephro toxic agent.

It causes irritation to renal tubules.

Due to other reasons like infection, decreased renal perfusion etc may leads to Intra tubular obstructions.

The abnormal reabsorption of filtrates and decreased urine flow through the tubules occurs.

As a result of it vasoconstriction and changes in glomerular permeability occurs.

Due to the changes, the glomerular filtration rate decreases, fluid and electrolyte imbalances occurs .

progressive azotemia also occurs.

Due to this changes parenchymal damage occurs in the glomeruli or kidney tubules.

It leads to acute tubular necrosis.

Nephrotoxic Acute tubular necrosis is a reversible condition. it occurs as a result of toxicity. By treating the causes it is possible to correct acute renal failure.