Polimorfismos en el ADN mitocondrial en pacientes con ablación vestibular por la administración de gentamicina.

Background: Aminoglycosides are a group of antibiotics with great antimicrobial potential against severe infectious diseases and infections produced by organisms multi-resistant to other antibiotics. Their administration should be regulated due to their toxic consequences for auditive-vestibular and renal systems. Objective: To identify mitochondrial DNA mutations associated to hypersensitivity to aminoglycoside in Mexican patients. Patients and method: A comparative study of three patients treated with gentamicin was done. Clinical tests were performed to determine auditory and vestibular function. Mitochondrial DNA analysis was determined in peripheral blood samples by molecular biological techniques. Resulting oligonucleotides were sequenced and compared with existing normal reference sequences (rCRS) reported for human mitochondrial DNA. Results: Clinical studies of vestibular function of the three patients evidenced no damage in one of the patients whereas the remaining two showed severe vestibular affection. After a long period of rehabilitation, only one patient of the two affected recovered vestibular function. In none of the cases, auditory function was compromised. When mitochondrial DNA sequences were attained, some changes were evident in the three patients, some of them localized in the hypervariable regions 2 and 3; the most numerous changes were found in the patient showing no recovery of vestibular function, especially where transcription factors bind to mitochondrial DNA, thus affecting deeply the mitochondrial function. Conclusion: Some of the modifications found in mitochondrial DNA sequence can be responsible for vestibular damage caused by gentamicin and of the absence of recovery of vestibular function. [ABSTRACT FROM AUTHOR]