Glomerular and Tubular Renal Function after Repeated Once-Daily Tobramycin Courses in Cystic Fibrosis Patients.

Florian Stehling,Rainer Büscher,Peter F Hoyer,Jörg Grosse-Onnebrink,Uwe Mellies

doi:10.1155/2017/2602653

Abstract

Introduction. Antibiotic treatment regimens against Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) patients often include aminoglycoside antibiotics that may cause chronic renal failure after repeated courses. Aminoaciduria is an early marker of acute aminoglycoside-induced renal tubular dysfunction. We hypothesized that urinary amino acid reabsorption is decreased after repeated once-daily tobramycin therapies. Methods. In this prospective cross-sectional study creatinine clearance was estimated by the Schwartz and the Cockcroft-Gault formula. Tubular amino acid reabsorption was determined by ion exchange chromatography in 46 patients with CF who received multiple tobramycin courses (6.3 ± 10.1 (1–57)) in a once-daily dosing regimen and 10 who did not. Results. Estimated creatinine clearance employing the Cockcroft-Gault was mildly reduced in 17/46 (37%) of the patients who received tobramycin and 5/10 (50%) of the patients who did not but in none using the Schwartz formula. No association with lifetime tobramycin courses was found. Tubular amino acid reabsorption was not influenced by the amount of once-daily tobramycin courses. Conclusion. Clinically not significant reduction of eCCL occurred in a minority of CF patients. However, chronic tubular dysfunction was not present in patients with CF repeatedly treated with tobramycin in the once-daily dosing scheme.

Highlights

Antibiotic treatment regimens against Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) patients often include aminoglycoside antibiotics that may cause chronic renal failure after repeated courses
In our study subjects treated with aminoglycosides (=Tob+ group) were older and had advanced CF disease with chronic Pseudomonas aeruginosa lung infection, when compared with Tob− group (Table 1)
The 46 subjects (21.2 ± 9.0 (9– 46) years) treated for Pseudomonas aeruginosa infections received a mean number of 6.3 ± 10.1 (1–57) intravenous antibiotic courses (corresponding to 44105 ± 80836 mg (520–480800 mg) or 487 ± 530 mg/kg (10–2890 mg/kg)) that included tobramycin given once daily

Summary

Introduction

Antibiotic treatment regimens against Pseudomonas aeruginosa lung infection in cystic fibrosis (CF) patients often include aminoglycoside antibiotics that may cause chronic renal failure after repeated courses. Tubular amino acid reabsorption was determined by ion exchange chromatography in 46 patients with CF who received multiple tobramycin courses (6.3 ± 10.1 (1–57)) in a once-daily dosing regimen and 10 who did not. Extensive antibiotic regimens to control Pseudomonas aeruginosa infections usually include aminoglycosides that are known to cause acute and chronic renal failure. Repeated courses of aminoglycoside antibiotics may cause chronic renal insufficiency [7], but data are controversial [8]. Those results are derived from retrospective data during the era when aminoglycosides were given three times daily. Since the early 2000s most CF centres adapted to the once-daily aminoglycoside dosing regimen with the aim of reducing nephrotoxicity [9]

Methods

Results

Conclusion