Intravenously administered pharmaceuticals impact biofilm formation and detachment of Staphylococcus lugdunensis and other staphylococci

Coagulase-negative staphylococci and Staphylococcus aureus are major causes of catheter-related infections because of their ability to form biofilms on indwelling polymeric devices. Staphylococcus lugdunensis is a particularly virulent coagulase-negative species responsible for several types of biofilm-related infections, but factors that influence biofilm formation by this species remain undetermined. Heparin and catecholamine inotropes are common intravenously administered drugs reported to stimulate biofilm formation of some staphylococci. This study assessed the effects of catecholamines and heparin on biofilm formation of a collection of S. lugdunensis isolates and other Staphylococcus species. Dopamine stimulated biofilm formation in two-thirds of S. lugdunensis isolates, whereas dobutamine prevented nearly all S. lugdunensis isolates from adhering to polystyrene. Heparin markedly reduced biofilm formation by 87% of S. lugdunensis isolates. Preformed biofilms of S. lugdunensis and other Staphylococcus species detached from polystyrene after exposure to heparin at concentrations used in catheter locks. Our data suggest that intravenous pharmaceuticals may influence staphylococcal biofilm formation on and detachment from intravascular catheters.