The client at highest risk for nephrotoxicity with aminoglycoside use is a:
A. Male with a creatinine of 1.7 and BUN of 52 on a 10-day regimen.
B. Female with BUN of 12 and creatinine of 0.8.
C. Female with past history of cystitis on 5 days of therapy.
D. Male with history of kidney stones on 8 days of therapy.
Correct Answer: A. Male with a creatinine of 1.7 and BUN of 52 on a 10-day regimen
Aminoglycosides preferentially affect the proximal tubular cells. These agents are freely filtered by the glomeruli and quickly taken up by the proximal tubular epithelial cells, where they are incorporated into lysosomes after first interacting with phospholipids on the brush border membranes. They exert their main toxic effect within the tubular cell by altering phospholipid metabolism. In addition to their direct effect on cells, aminoglycosides cause renal vasoconstriction.
Option B: A 24-year-old woman with a normal BUN and creatinine would not be at higher risk than others when given aminoglycosides.
Option C: Recurrent cystitis on limited-time therapy does not present a high risk for nephrotoxicity.
Option D: A history of kidney stones on limited-time therapy does not present a high risk for nephrotoxicity.