Aetiology of suspected bloodstream infection associated with an intravenous catheter

Staphylococcus aureus and coagulase-negative staphylococci are the most common causes of bacteraemia associated with all intravenous catheters. Less commonly, other organisms such as gram-negative bacteria and Candida species can cause infection in patients with immune compromise. Sepsis or septic shock associated with an intravenous catheter, and superficial septic vein thrombosis (septic thrombophlebitis), are usually caused by S. aureus.