Ototoxicity of Lividomycin

Abstract

Ototoxicity of lividomycin (LVM), recently developed aminoglycoside antibiotic, was functionally as well as histopathologically evaluated in guinea pigs of Hartley strain (300g body weight at the start of the experiment). Sixty three guinea pigs were divided into following 5 groups.Group 1 (10 guinea pigs), each animal received LVM intramuscularly at dosis of 100mg/kg body weight.Group 2 (21 guinea pigs), each received LVM intramuscularly at dosis of 200mg/kg.Group 3 (11 guinea pigs), each received LVM intramuscularly at dosis of 400mg/kg.Group 4 (10 guinea pigs), each received KM intramuscularly at dosis of 100mg/kg.Group 5 (11 guinea pigs), each received KM intramuscularly at dosis of 200mg/kg.The antibiotics were given to the animals for 4 weeks. Pinna reflex test was performed before, during and after the experiment with audiometer. Frequencies of the audiometer ranged from 10, 000Hz to 500Hz. The animals underwent vital fixation with Wittmaack's fixative under general anesthesia after the end of the experiment. The temporal bones were en bloc removed from the skull and further fixed in the same fixative for one week. The temporal bones were embeded in celloidin after decalcification. The horizontally sectioned serial celloidin sections were stained with hematoxylin-eosin. Histopathological examination was performed on the spiral organ of the cochlea and the vestibular organ, with special reference to the extent of hair cell damage in the cochlea. The results obtained were as follows:1) LVM was ototoxic in guinea pigs at the dosis of 200 and 400mg per kg body weight. The ototoxicity was much prominent in the hair cells of the spiral organ. In the basal turn of the cochlea the outer hair cells were more sensitive to the antibiotic than the inner hair cells, but in the apical and 4th turns the inner hair cells were more vulnerable than the outer ones. The loss of the outer hair cells, that is advanced damage, started from the basal end and indicated a general tendency to spread upwards.2) LVM showed almost the same ototoxicity as KM at the dosis of 200mg/kg body weight in guinea pigs.