An antibiotic sensitivity (or susceptibility) test is done
to help choose the antibiotic that will be most effective against the specific
types of bacteria or fungus infecting an individual person.
types of bacteria or fungus are resistant to certain antibiotics because of
differences in their genetic material (genes). Infections caused by resistant
bacteria or fungi are not cured by treatment with those antibiotics.
Drug-resistant bacteria or fungi usually develop because the entire
course of antibiotic treatment was not completed. Stopping drug treatment early
kills only the bacteria or fungi that are sensitive to the drugs, allowing the
resistant bacteria or fungi to multiply and cause an infection.