Related Experiment Videos
[Clinical studies on gentamicin (author's transl)]
Unlabelled:
Gentamicin (GM) was studied for on its antibacterial activity, absorption, and excretion, effect on the kidney and clinical effects. The results obtained are as follows: 1. Antibacterial activity: The susceptibility of E. coli, Klebsiella, Proteus mirabilis to GM was almost the same between the periods of 1964 to 1966 and 1972 to 1974: No tendency of increase of resistance by year was noted. However, against Pseudomonas aeruginosa, strains showing sensitivity to a concentration of more than 25 mcg/ml were isolated in 12.7%, in the latter period (1972-1974), as compared with the former period (1964-1966), which was 0%. 2. Blood levels: The peak level of GM in blood was obtained at 30 minutes after intramuscular injection to a healthy human. The peak level was 7.6 mcg/ml with 40 mg dose, 8.7 mcg/ml with 60 mg and 10.6 mcg/ml with 80 mg, showing a dose-responding curve. The half-life of GM absorption was 1.1 hours with 40 mg dose, 1.3 hours with 60 mg and 1.6 hours with 80 mg, showing also a dose related tendency. 3. Urinary levels: The peak level of GM in urine, about 200 mcg/ml, was noted in 0-2 hours after intramuscular injection of GM to a healthy human. The urinary recovery was about 44% in 6 hours. 4. Effect on the kidney: The effects of GM on the kidney was studied in rats administering 20 mg/kg once a day for 21 days consecutively. The results obtained are a slight increase (20 mg/dl) in BUN and a slight decrease (2,600 mosm/kg H2O) in urinary osmotic pressure; and urea lysozyme showed tendency to increase from the third day, the same as with kanamycin. Meanwhile, in the histopathological findings of the kidney tissue, the vacuolar degeneration and flattening of renal tubules were noted. Similar findings were obtained with kanamycin in a similar type of experiment. These results indicate that nephrotoxicity of GM is considered to be approximately the same as that of kanamycin. 5.
Clinical Results:
GM was injected into 22 patients with various infectious diseases (respiratory tract infections 7, liver abscess 1, urinary tract infections 14). Excellent efficacy was noted in 7 patients, good in 13 and no effect in 2. The effective rate was 90.9%. No serious side effect was noted in this clinical trial.
Insights
Gentamicin (GM) maintains antibacterial activity but shows increased resistance in Pseudomonas aeruginosa. Clinical trials demonstrate high efficacy (90.9%) with minimal side effects, though kidney effects were observed in rat studies.
Area of Science:
- Pharmacology and Microbiology
- Nephrology
- Clinical Medicine
Background:
- Gentamicin (GM) is a widely used antibiotic.
- Understanding its evolving antibacterial spectrum, pharmacokinetic profile, and potential toxicities is crucial for effective clinical application.
Purpose of the Study:
- To evaluate the current antibacterial activity of Gentamicin.
- To assess Gentamicin's absorption, excretion, and effects on kidney function.
- To determine the clinical efficacy and safety of Gentamicin in treating infections.
Main Methods:
- Antibacterial susceptibility testing of common pathogens.
- Pharmacokinetic studies involving blood and urine level analysis after intramuscular injection.
- Nephrotoxicity assessment in rats and histopathological examination of kidney tissue.
- Clinical trial evaluating Gentamicin in patients with various infections.
Main Results:
- Antibacterial activity against E. coli, Klebsiella, and Proteus mirabilis remained stable; however, resistance in Pseudomonas aeruginosa increased from 0% to 12.7%.
- Peak blood levels and absorption half-life showed a dose-dependent relationship after intramuscular administration.
- Urinary levels peaked within 2 hours, with approximately 44% recovery over 6 hours.
- Rat studies indicated mild nephrotoxicity, comparable to kanamycin, with increased BUN and decreased urinary osmotic pressure.
- Clinical trials in 22 patients showed a 90.9% efficacy rate for various infections, with no serious adverse events reported.
Conclusions:
- Gentamicin remains effective against many common bacteria, but emerging resistance in P. aeruginosa warrants monitoring.
- The drug exhibits predictable pharmacokinetics and a dose-dependent absorption profile.
- Nephrotoxicity, although present, appears comparable to other aminoglycosides like kanamycin.
- Gentamicin demonstrates significant clinical effectiveness and a favorable safety profile in treating diverse infections.