Sterile Body Fluids and Normally Sterile Tissues: In response to infection, fluid may accumulate in any body cavity. Wound, Abscess, Exudates: Skin and soft tissue infections can occur as a result of a break in the skin surface, or they can occur as complications of surgery; trauma; human, animal, or insect bites; or diseases that interrupt a mucosal or skin surface. Specimen collection is of utmost importance for these specimen types. For most open lesions and abscesses, remove the superficial flora by decontaminating the skin before collecting a specimen from the advancing margin or base. A closed abscess is the specimen site of choice. Aspirate the abscess contents with a syringe.

Any microorganism found where no resident flora is present is considered significant and is reported. For specimens contaminated with the usual bacterial flora, bacteria that are potentially pathogenic are identified.