Patent ID: 7648830

Claim:
A method for determining the presence of antibiotic-resistant bacteria in a biological sample, wherein cells of the antibiotic-resistant bacteria are resistant to a cell lysing antibiotic, comprising the sequential steps of: (i) incubating the sample in an incubating medium including the cell lysing antibiotic, wherein the cell lysing antibiotic lyses cells of bacteria in the sample that are not resistant to lysis by the cell lysing antibiotic and the lysed cells release intracellular material, and wherein the cell lysing antibiotic does not lyse cells of the antibiotic-resistant bacteria in the sample that are resistant to lysis by the cell lysing antibiotic, wherein the antibiotic-resistant bacteria is Staphylococcus aureus: (ii) immobilizing the unlysed cells of the antibiotic-resistant bacteria on a solid support, (iii) separating and removing the intracellular material from said support upon which the immobilized cells are attached, (iv) exposing the unlysed cells of the antibiotic-resistant bacteria to a cell lysing agent that is different from the cell lysing antibiotic in step (i), wherein the agent lyses the cells of the antibiotic-resistant bacteria and the lysed cells release intracellular material, and (v) detecting the intracellular material released from the lysed cells of the antibiotic-resistant bacteria, wherein detection of the intracellular material released from the lysed cells of the target antibiotic-resistant bacteria indicates the presence in the sample of bacteria resistant to the cell lysing antibiotic.