Aminoglycosides are broad-based heterosides with a broad-spectrum antibiotic action.
Streptomycin, dihydrostreptomycin, hydroxystreptomycin, manosidostreptomycin.
1,3 substitution (trisaccharide): kanamycin, amikacin, gentamicin, tobramycin, sisomicin, netilmicin.
1,2 substitution (tetrasaccharide): paramomycin, neomycin.
High for neomycin and streptomycin: >2% of treatments.
Occasional for gentamicin and amikacin: 0.1 to 2% of treatments.
Uncommon for kanamycin: 0.1 to 0.5% of treatments.
General: anaphylactic shock uncommon, fever (11% with long-term streptomycin), serum sickness.
Cutaneous: urticaria, rash (11% with streptomycin; 0.8% with gentamicin; 0.6% with tobramycin), contact dermatitis (3 to 10% with streptomycin), exfoliative dermatitis.
Haematological: eosinophilia, immunological blood dyscrasia.
Skin prick-tests: one case positive with systemic reaction in a patient with anaphylactic shock following topical use of framycetin (framycetin sulfate 10 mg/ ml).
- positive in 12% of patients treated with streptomycin.
- positive in patients presenting contact dermatitis, rash, fever.
- positive with neomycin in 10 to 35% of patients with leg ulcers.
The presence of antibodies against specific aminosides has rarely been demonstrated.
- antistreptomycin IgG antibodies in association with hemolytic anemia (direct and indirect Coombs);
- antierythrocyte antibodies (neomycin, gentamicin, kanamycin).
IgE-mediated hypersensitivity (rare).
Cell-mediated delayed hypersensitivity for contact dermatitis (neomycin) ; neomycin is the antibiotic with the highest contact sensitizing power. Sensitization tends to occur on altered skin (leg ulcers) and with long-term application.
Avoid use of offending antibiotics for leg ulcers. The use of neomycin should be avoided in dermatology.
Cross sensitivity between aminosides has been documented (neomycin-framycetin: 93% ; neomycin-ribostamycin 73% ; neomycin-kanamycin 60% ; neomycin-gentamycin 46% ; neomycin-tobramycin 40%).