Admin Table of Contents
How do aminoglycosides cause renal toxicity?
Aminoglycosides are nephrotoxic because a small but sizable proportion of the administered dose (≈5%) is retained in the epithelial cells lining the S1 and S2 segments of the proximal tubules (135) after glomerular filtration (30).
Is aminoglycoside nephrotoxicity reversible?
Although usually reversible, aminoglycoside-induced renal injury prolongs hospitalization time and increase patients cost. Even more important, the occurrence of nephrotoxicity is associated with higher patient mortality.
Why aminoglycosides are not metabolized?
Energy is needed for aminoglycoside uptake into the bacterial cell and intracellular transport is oxygen dependant; hence, anaerobes are resistant to aminoglycosides.
What are the toxic effects of aminoglycosides?
The toxicities of aminoglycosides include nephrotoxicity, ototoxicity (vestibular and auditory) and, rarely, neuromuscular blockade and hypersensitivity reactions. Nephrotoxicity receives the most attention, perhaps because of easier documentation of reduced renal function, but it is usually reversible.
Which patient is at the highest risk for aminoglycoside induced nephrotoxicity?
Patients at highest risk of drug-induced nephrotoxicity are those with one or more of the following: age older than 60 years, baseline renal insufficiency (e.g., GFR < 60 mL per minute per 1.73 m2), volume depletion, multiple exposures to nephrotoxins, diabetes, heart failure, and sepsis.
Which aminoglycoside is most Ototoxic?
The potential severity of auditory and vestibular deficits depends on the particular aminoglycoside used. Neomycin is considered the most highly toxic; followed by gentamicin, kanamycin, and tobramycin; while amikacin and netilmicin are considered the least toxic.
How do aminoglycosides affect renal function?
In addition to their direct effect on cells, aminoglycosides cause renal vasoconstriction. The 2 critical factors in the development of acute kidney injury (AKI) secondary to aminoglycoside nephrotoxicity are dosing and duration of therapy.
Why are aminoglycosides contraindicated in patients with kidney failure?
Effect of renal dysfunction Patients with decreased GFRs may have impaired cellular uptake of the drug. Therefore, patients with underlying kidney disease may not be able to attain adequate drug concentrations in the renal cortex to exert aminoglycoside-induced toxicity.
What organs can be affected by aminoglycosides?
The major side effects of aminoglycosides are kidney injury, hearing impairment and vestibular toxicity.
Which aminoglycoside is most nephrotoxic?
Choice of aminoglycoside The following rank order of nephrotoxicity has been reported, from most toxic to least toxic: neomycin > gentamicin ≥ tobramycin ≥ amikacin ≥ netilmicin > streptomycin [1].
Can aminoglycoside cause chronic kidney disease?
Chronic kidney disease. Regular courses of aminoglycoside antibiotics may cause subclinical kidney damage leading to chronic kidney disease (CKD). This can manifest at the level of the glomerulus (causing decreased glomerular filtration rate, GFR) and the tubules (causing altered excretion of electrolytes).
What are the side effects of aminoglycosides?
Since proteins are not properly synthesised, the small peptide chains cannot function as whole proteins which leads to incorrect cell function and bacteria cell death. Side effects of aminoglycosides. The most potent side effect associated with aminoglycosides is its toxic affect on the kidney.
What is the pathophysiology of aminoglycoside toxicity?
Regular courses of aminoglycoside antibiotics may cause subclinical kidney damage leading to chronic kidney disease (CKD). This can manifest at the level of the glomerulus (causing decreased glomerular filtration rate, GFR) and the tubules (causing altered excretion of electrolytes). The stages of CKD are shown in table 1.
What is the most potent nephrotoxic aminoglycoside?
The most potent side effect associated with aminoglycosides is its toxic affect on the kidney. The central element of this aminoglycosidic nephrotoxcity is tubular cytotoxicity. Gentamicin is the most potent nephrotoxic aminoglycoside upon which most studies on aminoglycoside nephrotoxicity are based.