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Experimental morphological and functional study of gentamicin cochleotoxicity using the regular dose given to
Carla Luiza Baggio1, Aron Ferreira Silveira, Miguel Angelo Hyppolito
1Hospital das Forças Armadas de Brasília. cabaggio@ig.com.br
Background:
gentamicin is an antibiotic that acts in Gram-negative bacilli infections, having as a side effect ototoxicity. Ototoxicity is an iatrogenic disturb provoked by drugs that modify the internal ear, affecting the cochlear and/or vestibular system and causing alterations in two important functions: equilibrium and audition. The main pediatric groups that receive aminoglicosides antibiotics are newborns who present serious infections in Neonate intensive care units.
Aim:
to verify the occurrence of external ciliary cells (ECC) caused by gentamicin with single dose schemas of 4 mg/kg/day and 2,5mg/kg/day every 12 hours, through a morphological - scanning electronic microscopy (SEM) and functional - distortion product otoacoustic emissions (DPOAE) experimental study.
Method:
26 albino guinea pigs were evaluated through DPOAE pre and post gentamicin treatment. The guinea pigs were sacrificed in the programmed time after the intramuscular administration of the drugs for anatomic analysis using MEV.
Results:
the evaluation of the functional state of the ECC indicated preservation of the DPOAE in all of the guinea pigs. The SEM results, after being photographed were analyzed in terms of the number of the ECC in the cochlear basal turn in a specific photographic field.
Conclusion:
lesions or alterations in the functioning of the ECC of albino guinea-pigs after the use of 4 mg/Kg/day and 2,5mg/Kg/day every 12 hours for a period 10 and 14 days were not observed.
Insights
Gentamicin did not cause damage to external ciliary cells (ECC) in guinea pigs, preserving hearing function. This study assessed gentamicin
Area of Science:
- Ototoxicology
- Pharmacology
- Otoacoustic Emissions
Background:
- Gentamicin, an antibiotic for Gram-negative infections, can cause ototoxicity, affecting hearing and balance.
- Ototoxicity impacts the cochlear and vestibular systems, crucial for audition and equilibrium.
- Neonate intensive care units frequently use aminoglycoside antibiotics in newborns with severe infections.
Purpose of the Study:
- To investigate gentamicin-induced external ciliary cell (ECC) damage.
- To evaluate gentamicin's ototoxicity using specific dosage regimens (4 mg/kg/day and 2.5 mg/kg/day every 12 hours).
- To employ both morphological (SEM) and functional (DPOAE) assessments.
Main Methods:
- 26 albino guinea pigs were used in the experimental study.
- Distortion product otoacoustic emissions (DPOAE) were measured pre- and post-gentamicin treatment.
- Scanning electron microscopy (SEM) was utilized for anatomical analysis of cochlear structures.
Main Results:
- Functional assessment via DPOAE showed preservation of hearing function in all treated guinea pigs.
- Morphological analysis using SEM did not reveal damage to external ciliary cells (ECC) in the cochlear basal turn.
- No observable lesions or functional alterations in ECC were detected post-gentamicin administration.
Conclusions:
- The tested gentamicin dosage regimens did not induce ototoxicity in the guinea pig model.
- External ciliary cells (ECC) and their function remained intact.
- Gentamicin, at the evaluated doses and durations, appears safe for cochlear function in this model.
