Staphylococcus epidermidis is a Gram-positive bacterium, and one of over 40 species belonging to the genus Staphylococcus.[1] It is part of the normal human flora, typically the skin flora, and less commonly the mucosal flora.[2] Although S. epidermidis is not usually pathogenic, patients with compromised immune systems are at risk of developing infection. These infections are generally hospital-acquired.[3] S. epidermidis is a particular concern for people with catheters or other surgical implants because it is known to form biofilms that grow on these devices.[4] Being part of the normal skin flora, S. epidermidis is a frequent contaminant of specimens sent to the diagnostic laboratory.[5]