Amikacin infection

General Antibacterial Properties. In the clinical control of bacterial infectious disease, the aminoglycosides gentamicin, tobramycin, amikacin, netilmicin, and to a lesser extent, dibekacin and isepamicin are most commonly used for the treatment of serious infections involving aerobic or facultative gram-negative baciUi, especially in the compromised host. This usage is discussed in the Hterature (44—51). 

Aminoglycoside Amikacin and gentamycin Infections caused by Gram-negative bacteria such as E. coli and Klebsiella... 

Gentamicin and tobramycin are equally effective gentamicin is less expensive. Tobramycin has better pseudomonal activity, which may be important in serious systemic infections. Amikacin generally is reseived for multiresis-tant bacteria. 

Newer examples of aminoglycoside antibiotics include amikacin, neomycin (Neosporin, Cortisporin), and tobramycin (TOBI, TobraDex). Injectable tobramycin is used in the treatment of serious infections at many body sites. It has also been formulated in an inhalable dosage form that has a very specific use to treat cystic fibrosis patients having Pseudomonas aeruginosa lung infections. In the form suitable for inhalation by the patient, it delivers the antibiotic directly to the site of infection. 

Amikacin is indicated for the treatment of genital tract infections in the mare by intra-uterine infusion. 

Penicillin plus streptomycin is effective for enterococcal endocarditis and 2-week therapy of viridans streptococcal endocarditis. Gentamicin has largely replaced streptomycin for these indications. Streptomycin remains a useful agent for treating enterococcal infections, however, because approximately 15% of enterococcal isolates that are resistant to gentamicin (and therefore to netilmicin, tobramycin, and amikacin) will be susceptible to streptomycin. 

M avium complex Pulmonary disease in patients with chronic lung disease disseminated infection in AIDS Amikacin, azithromycin, clarithromycin, ciprofloxacin, ethambutol, rifabutin... 

M chelonae Abscess, sinus tract, ulcer bone, joint, tendon infection Amikacin, doxycycline, imipenem, macrolides, tobramycin... 

Generally, streptomycin and gentamicin are used to treat infections with gram-positive organisms, whereas gentamicin, tobramycin, and amikacin are used to treat infections with gram-negatives. 

Not all mycobacterial infections are caused by M. tuberculosis or M. leprae. These atypical mycobacteria require treatment with secondary medications as well as other chemotherapeutic agents. For example, M. marinum causes skin granulomas, and effective drugs in the treatment of infection are rifampin or minocycline. Mycobacterium fortuitum causes skin ulcers and the medications recommended for treatment are ethambutol, cycloserine, and rifampin in combination with amikacin. 

B. V. Wichert, R. J. Gonalez-Rothi, L. E. Straub, B. M. Wichert, and H. Schreier, Amikacin liposomes preparation, characterization, and in vitro activity against Mycobacterium avium-intracellulare infection in alveolar macrophages, Int. J. Pharm. 78 221 (1992). 

Tobramydtt. The antibacterial activity and pharmacokinetic properties of tobramycin resemble those of gentamicin, and the therapeutic uses of tobramycin are essentially identical to those for gentamicin. Although some bacteria are resistant to both gentamicin and tobramycin, it is impredictable in individual strains. Amikacin is usually effective for infections caused by organisms resistant to both gentamicin and tobramycin. 

Several trisaccharides containing amino sugars are potent antibiotics used in the treatment of certain severe and recurrent bacterial infections. These compounds, such as tobramycin and amikacin, are called amint ycoside antibiotics. 

Amikacin is mainly of value because it is more resistant to aminoglycoside-inactivating bacterial enzymes than is gentamicin. Since it is more costly, amikacin is reserved for treatment of infections with gentamicin-resistant organisms. Peak plasma concentrations should be kept between 20-30 mg/1 and trough concentrations below 10 mg/1. 

Erman M, Akova M, Akan H, Korten V, Ferhanoglu B, Koksal I, Cetinkaya Y, Uzun O, Unal S Febrile Neutropenia Study Group of Turkey. Comparison of cefepime and ceftazidime in combination with amikacin in the empirical treatment of high-risk patients with febrile neutropenia a prospective, randomized, multicenter study. Scand J Infect Dis 2001 33(11) 827-31. 

Feld R, Valdivieso M, Bodey GP, Rodriguez V. Comparison of amikacin and tobramycin in the treatment of infection in patients with cancer. J Infect Dis 1977 135(l) 61-6. 

Noone M, Pomeroy L, Sage R, Noone P. Prospective study of amikacin versus netilmicin in the treatment of severe infection in hospitalized patients. Am J Med 1989 86(6 Pt 2) 809-13. 

Whitehead TC, Lovering AM, Cropley IM, Wade P, Davidson RN. Kinetics and toxicity of liposomal and conventional amikacin in a patient with multidrug-resistant tuberculosis. Eur J Clin Microbiol Infect Dis 1998 17(ll) 794-7. 

In a leading cancer center in Houston, 24% of 758 Gram negative clinical isolates were resistant to tobramycin and 12% were resistant to amikacin (138). In 3144 bacterial isolates causing urinary tract infections in Chile, 74% were identified as Escherichia colv, 4.2% of these strains were resistant to gentamicin, and 1.3% were resistant to amikacin (139). In contrast, the resistance levels were 30% and 17% respectively, in the other enterobacterial strains. In Brazil, all isolates of methicillin-resistant S. aureus were also resistant to gentamicin, amikacin, kanamycin, neomycin, and tobramycin (140), and 97% of such strains from Spain were resistant to tobramycin (141). 

Once-daily amikacin was as effective and safe as twice-daily dosing in a prospective randomized study in 142 adults with systemic infections (160). 

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