Aminoglycosides

In addition to streptomycin, which is only used as a tuberculostat and in Malta fever (zoonosis caused by Brucella melitensis), the most important systemically used agents are:

• (Streptomycin)
• gentamicin
• Tobramycin
• amikacin
• fusomycin

Other aminoglycosides are only used topically (gentamicin is used systemically and topically):

• Kanamycin
• Framycetin
• Paromomycin (administered orally but not absorbed; used exclusively to reduce the intestinal flora and eradicate Entamoeba histolytica)

Aminoglycosides are taken up through the bacterial cytoplasmic membrane via a secondary active transport mechanism. They inhibit bacterial protein synthesis by binding with high affinity to the 30S subunit of bacterial ribosomes, thereby interfering with translation. The defective proteins synthesized as a result of reading errors lead to damage to the bacterial cell membrane and ultimately cause the bactericidal effect - both in the proliferation and resting stages of gram-positive and gram-negative germs.

The bactericidal effect increases depending on the concentration. It is advisable to achieve the highest possible peak concentrations by applying the dose once in the morning. This also reduces the toxicity of the active substance.

Acinetobacter spp, Aeromonas hydrophilia, Citrobacter spp, Enterobacter spp, E. coli, Haemophilus influenzae, Hafnia alvei, Klebsiella spp, Morganella morganii, Proteus spp, Providencia spp., Pseudomonas aeruginosa, Salmonella spp., Serratia spp., Shigella spp., Staphylococcus spp., Streptococcus spp., Yersinia spp. (see also Amikacin, Gentamicin, Netilmicin, Tobramycin)

Note! No absorption with oral application: application parenterally or topically.

Nephrological ADRs:

• Reversible nephrotoxicity with proteinuria, cylindruria, hematuria and elevated serum creatinine. Risk factors are an increased total dose and a long duration of therapy. An increased trough level also leads to increased toxicity (therefore only single application).

Neurological ADRs:

• neuromuscular blockade (antidote: calcium gluconate)
• paraesthesia
• Ototoxicity (irreversible), especially with impaired renal function. Symptoms are nausea, tinnitus, dizziness, hearing loss. Amikacin mainly causes hearing disorders, gentamycin vestibular disorders, tobramycin both at the same time.
• Myalgias

Opthalmologic ADR:

• Eye muscle paralysis

Hematologic ADR:

• Blood count disturbances

Heptatologic ADR:

• Transaminase increase

Immunological ADR:

• allergic reactions up to anaphylactic shock
• Drug fever

Hematologic ADR:

• Thrombocytopenia
• leukopenia
• eosinophilia

Pregnancy, lactation, hypersensitivity to aminoglycosides, pre-damage of the vestibular or cochlear organ, terminal renal failure, myasthenia gravis, Parkinson's disease, sulphide hypersensitivity in bronchial asthma.

Cave! Preexisting kidney damage. Good synergistic effect with β lactam antibiotics. Under therapy regular control of BB and kidney values. Therapy duration preferably not more than 10 days! In case of renal insufficiency extension of the dosage intervals. Infusion duration about 30 minutes to avoid a neuromuscular blockade!

Representative of the family of aminoglycoside antibiotics:

• amikacin
• Gentamycin
• Tobramycin

Useful combinations with other antibiotics:

• Aminoglycoside + piperacillin against pseudomonads
• Aminoglycoside + ampicillin against listeria
• Aminoglycoside + Cefalosporine against Klebsiellen