No abstract available.
Gentamicins*

The histopathological alterations in the vestibule due to aminoglycosides are well defined. Although there are reports comparing the vestibulotoxic effects of the many aminoglycosides, this is the first study to compare the effects of the most commonly used aminoglycosides i.e., streptomycin, gentamicin, amikacin and netilmicin administered both transtympanically and systemically. The transtympanic and systemic administration of each aminoglycoside caused similar histopathological alterations in the vestibule. The most severe degeneration in the cristae ampullaris, utriculus and sacculus was observed after streptomycine administration. The severity of the vestibular damage in terms of magnitude was in the order of streptomycine, gentamicin, amikacin, and netilmicin.
Amikacin/administration & dosage/*poisoning ; Animals ; Comparative Study ; Gentamicins/administration & dosage/*poisoning ; Guinea Pigs ; Injections, Intraperitoneal ; Netilmicin/administration & dosage/*poisoning ; Streptomycin/administration & dosage/*poisoning ; Tympanic Membrane ; Vestibule/*drug effects

BACKGROUND: Once daily dose of aminoglycoside has been used recently in the gram-negative infection for the purpose of improving efficacy. The clinical efficacy and side effects of once daily versus divided doses of gentamicin were compared in acute pyelonephritis. METHOD: Gentamicin (3-5mg/kg/day) was administered into 3 divided doses intravenously in 15 patients of the divided dose group, and the same dose was administered at a time in 19 patients of the once daily dose group. The duration of treatment was 6-14 days. RESULTS: The clinical outcome of all patients was favorable, and nephrotoxicity or ototoxicity was not detected in any patients. E. coli were isolated from 12 patients in the divided dose group, and 15 patients in the once daily dose group. They were all eradicated after treatment. The mean peak serum concentrations of gentamicin were 5.33+/-1.99;g/mL in the divided dose group, and 14.79+/-5.71g/mL in the once daily dose group. The trough concentrations were not different significantly between two groups(0.69+/-0.58;g/mL in the divided dose group vs. 0.35+/-0.45g/mL in the once daily dose group). The number of patients with peak concentration over 5.0g/mL was 8 out of 15 in the divided dose group. CONCLUSION: The once daily dose of gentamicin was as effective as the divided dose, and the nephrotoxicity or ototoxicity was not observed in both groups.
Gentamicins* ; Humans ; Pyelonephritis*

No abstract available.
Gentamicins* ; Humans ; Infant, Newborn*

No abstract available.
Bismuth* ; Gentamicins* ; Mercuric Chloride*

In 189 consecutive non-inflamed anophthalmic patients wearing uniocular prosthesis, the conjunctival flora was evaluated and compared to that of the opposite healthy eye. And this results were compared with that of department of clinical pathology studied from January 1997 to July 1998. The incidence of bacterial isolation on the anophthalmic side (63.5%) was significantly higher than that on the healthy side (28.0%). Especially, the incidence of potential pathogenic bacterial isolation. (S.aureus, streptococci spp. and gram-negative bacilli grouped together) on the anophthalmic side (42.3%) was very significantly higher (p<0.001) than that on the healthy side (6.9%).The antimicrobial susceptibility to ciprofloxacin was high (>90%) in all bacterial isolate from the both anophthalmic socket and fellow normal conjunctiva. The bacteria isolated from the anophthalmic socket and fellow normal conjunctiva were similarly sensitive to vancomycin,clindamycin, gentamicin, imipenem, tobramycin, amikacin, netilmicin, colistin and were resistant to penicillin, ampicillin and tetracycline. No significant difference in the anophthalmic conjunctival flora between our study and the previous report but the antimicrobial susceptibility to clindamycin in coagulase-negative staphlyococcus (CNS) and S.aureus from the anophthalmic socket is higher than that of the previous report. The antimicrobial susceptibility to erythromycin in gram-positive bacteria except coagulase-negative staphlyococcus (CNS) and S.aureus from the anophthalmic socket is lower than that of the previous report. The species isolated from our study were more sensitive to the majority of antimicrobial agents than that of the microbial laboratory report. But,the antimicrobial susceptibilities of our study to chloramphenicol and colistin were very significantly lower than that of the microbial laboratory report (p<0.001).
Amikacin ; Ampicillin ; Anti-Infective Agents ; Bacteria* ; Chloramphenicol ; Ciprofloxacin ; Clindamycin ; Colistin ; Conjunctiva* ; Erythromycin ; Eye, Artificial ; Gentamicins ; Gram-Positive Bacteria ; Humans ; Imipenem ; Incidence ; Netilmicin ; Pathology, Clinical ; Penicillins ; Prostheses and Implants ; Tetracycline ; Tobramycin

BACKGROUND: Staphylococcus aureus is one of the most important pathogens, causing severe morbidity and fatal infections. To date rapid evolution of antibiotic resistance in S. aureus, including recent emergence of vancomycin-resistant S. aureus (VRSA), has been a serious concern and an obstacle to the effective treatment. The purpose of this study is to update the resistance patterns against aminoglycoside antibiotics which play an important role in the therapy of serious staphylococcal infections. METHODS: Clinical isolates were collected from 8 university-affiliated hospitals during the period of June 1999 to January 2001. Susceptibility tests against 9 antibiotics were performed by disk diffusion method. Minimum inhibitory concentrations (MICs) of arbekacin against non-susceptible strains were determined by microbroth dilution method RESULTS: Among total 682 isolates exclusive of consecutive ones from the same patients, 199 (29%) were from pus, 152 (22%) from respiratory specimens, 137 (20%) from blood, 38 (6%) from urine. Of 682 isolates, 588 (87%) isolates were resistant to at least one of the aminoglycosides tested. Overall prevalence of MRSA was 64% (439/682), and resistance rates of MRSA were summarized as follows; kanamycin (KM) 98%, tobramycin (TOB) 98%, gentamicin (GM) 95%, amikacin (AMK) 90%, neomycin (NEO) 63%, streptomycin (SM) 31%, netilmicin (NET) 18%, arbekacin (ABK) 13%. MRSA isolates were resistant to multiple aminoglycosides, and 88% of them were resistant to all four aminoglycosides of KM, TOB, GM, and AMK. MICs of ABK against 58 non-susceptible strains ranged from 2 to 128 microgram/mL. CONCLUSION: More than 90% of MRSA isolates were resistant against kanamycin, tobramycin, gentamicin, and amikacin. Moreover, most of MRSA isolates were multi-drug resistant to all these four aminoglycosides. Resistance rates against arbekacin and netilmicin were less than 20%. Arbekacin was the most susceptible antibiotic of the aminoglycosides tested.
Amikacin ; Aminoglycosides ; Anti-Bacterial Agents* ; Diffusion ; Drug Resistance, Microbial ; Gentamicins ; Humans ; Kanamycin ; Methicillin-Resistant Staphylococcus aureus ; Microbial Sensitivity Tests ; Neomycin ; Netilmicin ; Prevalence ; Staphylococcal Infections ; Staphylococcus aureus ; Streptomycin ; Suppuration ; Tertiary Care Centers* ; Tobramycin

BACKGROUND: Many genes encoding aminoglycoside modifying enzymes (AMEs) on transposon or plasmid were transferred from one strain to another strain and inserted into a staphylococcal chromosomal cassette mec (SCCmec). There are very diverse subtypes in SCCmec type to the insertion of resistant genes. Therefore, we researched the resistance rates of antibiotics and distribution of AME genes according to SCCmec type in MRSA strains. MATERIALS AND METHODS: We isolated 640 Staphylococcus aureus from non-tertiary hospitals in 2004, detected mecA, aac(6')-aph(2"), aph(3')-IIIa, and ant(4')-Ia using the multiplex PCR method, tested antibacterial susceptibility disk diffusion and minimal inhibitory concentration, and determined SCCmec type. RESULTS: Of 640 S. aureus isolates, MRSA rate was 39.7% and all MRSA isolates carried mecA gene. Among 214 MRSA selected, aminoglycoside-resistant rates were 98.1% in kanamycin and tobramycin, 68.7% in gentamicin, 30.8% in amikacin, and 2.8% in netilmicin. The detection rates for aac(6')-aph(2"), aph(3')-IIIa, and ant(4')-Ia were 77.1%, 13.1%, and 53.3%, respectively. Also, SCCmec type was 50.9% in SCCmec type II, 16.4% in type III, and 32.7% in type IV. The genes encoding AMEs were distributed aac(6')-aph(2") (49.5%) and aac(6')-aph(2")/ant(4')-Ia (36.7%) in SCCmec type II, aph(3')-IIIa/aac(6')-aph(2") (60%) and aac(6')-aph(2") (31.4%) in type III, and aac(6')-aph(2")/ant(4')-Ia (41.4%) and ant(4')-Ia (50%) in type IV. CONCLUSION: 39.7% of S. aureus isolated from non-tertiary hospitals was resistant to methicillin. More than 90% of MRSA isolates were detected aac(6')-aph(2") in SCCmec type II and III, and ant(4')-Ia in type IV. With these results, the genes encoding AMEs may be closed related to SCCmec type.
Adenosine ; Amikacin ; Amphotericin B ; Anti-Bacterial Agents ; Diffusion ; Gentamicins ; Kanamycin ; Kanamycin Kinase ; Methicillin ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Multiplex Polymerase Chain Reaction ; Netilmicin ; Plasmids ; Sprains and Strains ; Staphylococcus aureus ; Tobramycin

BACKGROUND: Many genes encoding aminoglycoside modifying enzymes (AMEs) on transposon or plasmid were transferred from one strain to another strain and inserted into a staphylococcal chromosomal cassette mec (SCCmec). There are very diverse subtypes in SCCmec type to the insertion of resistant genes. Therefore, we researched the resistance rates of antibiotics and distribution of AME genes according to SCCmec type in MRSA strains. MATERIALS AND METHODS: We isolated 640 Staphylococcus aureus from non-tertiary hospitals in 2004, detected mecA, aac(6')-aph(2"), aph(3')-IIIa, and ant(4')-Ia using the multiplex PCR method, tested antibacterial susceptibility disk diffusion and minimal inhibitory concentration, and determined SCCmec type. RESULTS: Of 640 S. aureus isolates, MRSA rate was 39.7% and all MRSA isolates carried mecA gene. Among 214 MRSA selected, aminoglycoside-resistant rates were 98.1% in kanamycin and tobramycin, 68.7% in gentamicin, 30.8% in amikacin, and 2.8% in netilmicin. The detection rates for aac(6')-aph(2"), aph(3')-IIIa, and ant(4')-Ia were 77.1%, 13.1%, and 53.3%, respectively. Also, SCCmec type was 50.9% in SCCmec type II, 16.4% in type III, and 32.7% in type IV. The genes encoding AMEs were distributed aac(6')-aph(2") (49.5%) and aac(6')-aph(2")/ant(4')-Ia (36.7%) in SCCmec type II, aph(3')-IIIa/aac(6')-aph(2") (60%) and aac(6')-aph(2") (31.4%) in type III, and aac(6')-aph(2")/ant(4')-Ia (41.4%) and ant(4')-Ia (50%) in type IV. CONCLUSION: 39.7% of S. aureus isolated from non-tertiary hospitals was resistant to methicillin. More than 90% of MRSA isolates were detected aac(6')-aph(2") in SCCmec type II and III, and ant(4')-Ia in type IV. With these results, the genes encoding AMEs may be closed related to SCCmec type.
Adenosine ; Amikacin ; Amphotericin B ; Anti-Bacterial Agents ; Diffusion ; Gentamicins ; Kanamycin ; Kanamycin Kinase ; Methicillin ; Methicillin Resistance ; Methicillin-Resistant Staphylococcus aureus ; Multiplex Polymerase Chain Reaction ; Netilmicin ; Plasmids ; Sprains and Strains ; Staphylococcus aureus ; Tobramycin

BACKGROUND: High-level gentamicin and streptomycin disks are not easily available, despite their critical role in detection of high-level resistance to aminoglycosides in enterococci. Therefore, the possibility of applicating home-made disks to test high-level resistance of enterococci to aminoglycosides was evaluated. METHODS: The disk diffusion method using home-made disks was compared with minimal inhibitory concentrations(MIC) in 53 clinical isolates of enterococci, and, the stability of the disks were also evaluated by disk diffusion testing, biweekly, for 14 weeks. RESULTS: The high-level resistance rates to gentamicin(GM) and streptomycin(SM) were 60% and 43%, respectively. Thirty eight % of the enterococci were highly resistant in both GM and SM. The results of the disk diffusion method were consistent with the MIC until 10 weeks after production of the disks. After 12 weeks, the inhibition zones of GM- or SM-susceptible strains decreased by 2.9-3.9 mm, and the discrepancy rates were 5-24% between the results of the MIC and disk diffusion method. The storage temperature of -20degrees C versus -70degrees C showed no difference in the inhibition zone. CONCLUSION: It has been demonstrated that home-made high-level GM and SM disks are stable at -20degrees C for 10 weeks, and the results of disk diffusion method on the disks show they are applicable for the test of susceptibility of aminoglycosides to enterococci.
Aminoglycosides ; Diffusion ; Enterococcus ; Gentamicins ; Streptomycin