Multi-resistant microbes are a growing danger. The often unnecessary and mass use of antibiotics causes the impassivity of pathogens against drugs. Infections that were easily curable up to now, may become life threatening. A new rapid test will give information on which available antibiotic is still effective. Faster diagnostics allow a personalized therapy and saves lives. A requirement for prevention of spreading antibiotic resistances is a targeted, economical and responsible application of broad-spectrum and last resort antibiotics.