Aminoglycoside-induced deafness in leukemic patients: Cost-effectiveness of prevention by genetic testing. Sub-category: Cancer-Related Complications Category: Patient Care Abstract No: 9014 Author(s): M. Bitner-Glindzicz, V. Osei-Lah, I. Colvin, T. Sirimanna, D. Lucas, B. MacArdle, D. Webb, A. Shankar, J. Kingston, L. Jenkins, S. Rahman Abstract: Background: Aminoglycosides are highly-effective, inexpensive antimicrobials widely used in empirical combination therapy for fever in children with severe neutropenia, including patients receiving treatment for acute leukemia. Some genetically predisposed individuals are exquisitely sensitive to the cochleotoxic effects of these drugs, even when levels are within the therapeutic range. This genetic susceptibility is maternally inherited and caused by mutation of the MT-RNR1 gene encoding mitochondrial 12S rRNA at base position 1555, termed m.1555A>G. Methods: Retrospective analysis of m.1555A>G positive cases in the Regional Diagnostic laboratory to determine how many were revealed by aminoglycoside treatment for cancer treatment-related sepsis. Results: Three unrelated mutation positive individuals were identified in a two year period. All were children with acute lymphoblastic leukemia who experienced rapidly progressive hearing loss during their treatment. Two of the three children have a post-lingual hearing loss of sufficient severity to merit cochlear implantation. None had a significant family history of deafness. Conclusions: Initial estimates of the prevalence of the m.1555A>G mutation were based upon extrapolation back from its contribution to the cause of hearing loss amongst hearing-impaired people and were thought to be low. However, recent small studies of the prevalence of m.1555A>G in the general population suggest that prevalence is much higher than previously calculated (1 in 206 in New Zealand (n=206), 1 in 1,161 in Texas (n=1,161)) but that penetrance, at least in the absence of aminoglycosides, is low. Using estimates of the lifetime cost of pediatric cochlear implantation we suggest that screening for the m.1555A>G mutation at the time of diagnosis of leukemia would be cost effective and therefore suggest that all children diagnosed with leukemia should be screened for this mutation prior to receiving aminoglycoside therapy. Citation: Journal of Clinical Oncology, 2007 ASCO Annual Meeting Proceedings Part I. Vol 25, No. 18S (June 20 Supplement), 2007: 9014 Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.