Nephrotoxicity tobramycin

Matzke GR, Lucarotti RL, Shapiro HS. Controlled comparison of gentamicin and tobramycin nephrotoxicity. Am J Nephrol 1983 3(1) 11-17. 

English J, Gilbert DN, Kohlhepp S, Kohnen PW, Mayor G, Houghton DC, Bennett WM. Attenuation of experimental tobramycin nephrotoxicity by ticarcillin. Antimicrob Agents Chemother 1985 27(6) 897-902. 

Beauchamp D, Theriault G, Grenier L, Gourde P, Perron S, Bergeron Y, Fontaine L, Bergeron MG. Ceftriaxone protects against tobramycin nephrotoxicity. Antimicrob Agents Chemother 1994 38(4) 750-6. 

Concomitant administration of piperacillin and cephaloridine to rabbits resulted in a significant protective effect against cephaloridine nephrotoxicity [153]. Cephaloridine nephrotoxicity can be prevented by administration of other cephalosporins or penicdhns that produce little or no reduction of the cortical concentration of cephaloridine [154]. However, ceftriaxone protects against tobramycin nephrotoxicity by reducing the intracortical accumulation of tobramycin [155]. Combination of tobramycin with latamoxef protects the rat kidney from tobramycin nephrotoxicity, and the protective effect may be partially due to suppression of intrarenal accumulation of tobramycin by latamoxef. This suppression of nephrotoxicity is roughly dependent on the latamoxef dosage [81,156]. 

Kojima R, Ito M, Suzuki Y. Studies on the nephrotoxicity of aminoglycoside antibiotics and protection from these effects (3). Protective effect of latamoxef against tobramycin nephrotoxicity and its protective mechanism. Jpn J Pharmacol 1986 42(3) 397-404. 

Wood CA, Kohihepp SJ, Kohnen PW, Houghton DC, Gilbert DN. Vancomycin enhancement of experimental tobramycin nephrotoxicity. Antimicrob Agents Chemother 1986 30 20-24. 

Kuhlmann J, Seidel G, Richter E, Grbtsch H, Tobramycin nephrotoxicity failure of cefotaxime to potentiate injury inpatient, Namyn Schmiedebergs Arch Pharmacol (1981) 316 (Sup-pi), R80,... 

Beauchamp D, Pellerin M, Gourde P. Petti ew M, Bergeron MG. Effects of daptomycin and vancomycin on tobramycin nephrotoxicity in rats. Antimicrob Agent Chemother 1990 34 139-147. 

Renal toxicity - Renal toxicity may be characterized by decreased creatinine clearance, cells or casts in the urine, decreased urine specific gravity, oliguria, proteinuria, or evidence of nitrogen retention. Renal damage is usually reversible. The relative nephrotoxicity of these agents is estimated to be Kanamycin = Amikacin = Gentamicin = Tobramycin Streptomycin. 

Avoid concurrent or sequential use of other neurotoxic and/or nephrotoxic drugs with streptomycin sulfate, including neomycin, kanamycin, gentamicin, cephaloridine, paromomycin, viomycin, polymyxin B, colistin, tobramycin, and cyclosporine. 

Like other aminoglycosides, tobramycin is ototoxic and nephrotoxic. Nephrotoxicity of tobramycin may be slightly less than that of gentamicin, but the difference is clinically inconsequential. 

Tobramycin Intravenous more active than gentamicin versus pseudomonas may also have less nephrotoxicity... 

Olsen KM et al Effect of once-daily dosing vs. multiple daily dosing of tobramycin on enzyme markers of nephrotoxicity. Crit Care Med 2004 32 1678. [PMID 15286543]... 

It is important to monitor peak and trough plasma levels (see p. 20) of gentamicin, tobramycin, netilmicin, and amikacin to avoid concentrations that cause dose-related toxicities (Figure 31.7). [Note Peak levels are defined as those obtained 1/2 to 1 hour after infusion. Trough levels are obtained immediately before the next dose.] Patient factors, such as old age, previous exposure to aminoglycosides, gender, and liver disease, tend to predispose patients to adverse reactions. The elderly are particularly susceptible to nephrotoxicity and ototoxicity. 

Answer The patient s high serum creatinine indicates compromised renal function. The aminoglycosides can be nephrotoxic and thus the drug was not employed. However, tobramycin might have been used together with ceftazidime if the dose were adjusted for renal function. 

Reiner NE, Bloxham DD, Thompson WL. Nephrotoxicity of gentamicin and tobramycin given once daily or continuously in dogs. J Antimicrob Chemother 1978 4(suppl A) 85-101. 

Tobramycin is similar to gentamicin it is more active against most strains of Pseudomonas aeruginosa and may be less nephrotoxic. It is commonly administered via a nebulizer for treatment of infective exacerbations of cystic fibrosis caused by pseudomonads or Enlerobacteriaceae. 

Netilmicin is a semisynthetic aminoglycoside which is active against some strains of bacteria that resist gentamicin and tobramycin evidence suggests that it may be less oto- and nephrotoxic. 

After administration of the recommended doses of amikacin for 10 days, renal damage probably occurs in less than 10% of cases. Limited data support the view that amikacin is less nephrotoxic than other aminoglycosides, possibly because of lower binding affinity to proximal tubular cells or reduced potential to cause phospholipidosis (SEDA-20,236). In several prospective randomized studies the liability of amikacin to cause nephrotoxicity was no greater than that of gentamicin or tobramycin (6-8). In a prospective study there was significantly lower nephrotoxicity with amikacin 15 mg/kg/day (4% toxicity) compared with netilmicin 7 mg/kg/day (12%) (9). As with other aminoglycosides, renal toxicity is reversible in most cases (10). 

Careful tailoring of the dose can prevent nephrotoxicity. In 89 critically ill patients with a creatinine clearance over 30 ml/minute who were treated with gentamicin or tobramycin 7 mg/kg/day independent of renal function, with subsequent doses chosen on the basis of the pharmacokinetics of the first dose, signs of renal impairment occurred in 14% in all survivors renal function recovered completely and hemofiltration was not needed (104). 

The pharmacokinetics of once-daily intravenous tobramycin have been investigated in seven children with cystic fibrosis (162). All responded well. There was one case of transient ototoxicity but no nephrotoxicity. 

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