Gentamicin and genetic testing. Mutations in mitochondrial DNA will predispose a person to high sensitivity to the antibiotic gentamicin. Just one dose can cause gentamicin-induced hearing loss, and it’s not a dose-dependent reaction.
A point of care aimed at identifying children at risk for drug-induced hering loss before they are treated with gentamicin, in which genotyping of mitochondrial DNA can be performed in approximately 20 minutes, was developed for the neonatal intensive care unit. But that plan was quashed because, in the NICU, you can introduce candida infections if you switch to the broad spectrum antibiotic cephalosporin. The infection then runs rampant, causing more morbidity than the gentamicin-related hearing loss. “Sound medical practices trump cool molecular diagnostics every time,” Dr. Choo said.
HPV. Human papilloma virus (HPV) can be used as an indicator of prognosis in head and neck cancer in those with HPV-positive disease, but its use is limited, said Christine Gourin, MD, associate professor of otolaryngology–head and neck surgery at Johns Hopkins Medical Center in Baltimore. “HPV is a prognostic biomarker; it is not a therapeutic target,” she said. “We don’t treat people differently in 2015, who are HPV positive, outside of some clinical trials in progress that are designed to see if clinical care can maybe be deintensified.”