Exploration of the relationship between cumulative exposure to tobramycin and ototoxicity in patients with cystic fibrosis.

BACKGROUND: Aminoglycosides (AGs), such as tobramycin, are essential antibiotics in the management of pulmonary infections in patients with cystic fibrosis (CF). They induce ototoxicity without the relationship being clearly described in the literature. Our aim is to propose a mathematical and statistical model describing the relationship between the estimated cumulative exposure (Area Under the Curve, AUC) to tobramycin and ototoxicity with audiogram interpretation in young patients with CF. METHODS: Cumulative AUCs were estimated for each course of tobramycin, for the 106 individuals with CF (between 4 and 22 years of age) enrolled in this retrospective study (35 who had received IV tobramycin, 71 controls). Mean hearing loss was calculated for each audiogram and a statistical model was developed to predict hearing loss. RESULTS: The model confirms a significant relationship between cumulative tobramycin exposure and changes in hearing acuity: Meanhearingloss=2.7+(3×10-5)×AUC_tobramycin+individual_susceptibility However, the ototoxic effect is not clinically perceptible (mean hearing loss: 3.8 dB). The impact of AUC on hearing loss is minor in these subjects who received a limited number of courses of tobramycin (median: 5 courses). CONCLUSION: A significant relationship between cumulative exposure to tobramycin and ototoxicity was demonstrated. Individual treatment susceptibility should not be overlooked. As ototoxicity is not clinically perceptible in the study subjects, hearing tests should be continued during adulthood to provide individualized medical guidance and to obtain a lifetime analysis of the relationship between exposure and hearing loss.

Ligamentoplastía en inestabilidad ligamentaria crónica lateral de tobillo. Reporte de tres casos tratados con la técnica de Brostrom modificada / Ligament plasty for chronic lateral ligament instability of the ankle joint. Report of 3 cases treated by the modified Bronstrom technique

Tres pacientes deportistas, dos femeninos y uno masculino fueron tratados quirúrgicamente por presentar inestabilidad crónica lateral de tobillo con la técnica de Brostrom modificada. Los resultados fueron excelentes en los tres casos, retornando todos ellos a las actividades deportivas que practicaban antes de la lesión