BACTEREMIA DUE TO RECURRENT REINFECTION WITH STAPHYLOCOCCUS-EPIDERMIDIS ASSOCIATED WITH DEFECTIVE OPSONIZATION AND PROCIDIN FUNCTION IN SERUM

Aims-To differentiate between reinfection and relapsing infection with Staphylococcus epidermidis in a middle-aged woman with defective opso nisation and procidin function in serum. Methods-Microbiological typin g was done by biotyping, phage typing, and polyacrylamide gel electrop horesis of radiolabelled bacterial proteins (radioPAGE method). Polymo rphonuclear cell function was assessed in vitro by phagocytosis and ki lling of Candida albicans; measurement of neutrophil random locomotion and chemotaxis; reduction of nitroblue tetrazolium after stimulation by opsonised Candida and a radiometric saccharomyces opsonisation assa y. The effect of plasma infusions on opsonic activity was assessed by chemiluminescence using control polymorphonuclear leucocytes with a la boratory strain of S epidermidis opsonised with either patient or cont rol serum. Results-Recurrent reinfection with different strains of Sta phylococcus epidermidis rather than relapsing infection was confirmed as having occurred by typing bacterial strains. The RadioPAGE method d etected all the S epidermidis strains involved in this patient's illne ss. The patient's serum was shown to be defective in both opsonin and procidin function. The defects were correctable in vitro by the additi on of normal serum. Clinical recovery occurred after repeated infusion s of normal fresh frozen plasma and prolonged antibacterial treatment; antibacterial treatment alone was insufficient. Conclusions-The radio PAGE method is useful in distinguishing recurrent reinfection with S e pidermidis from relapsing infection with this organism. Elucidation of the nature of, and underlying predisposition to, infection in the pat ient studied allowed a rational treatment plan of plasma infusion comb ined with antibacterial treatment to be devised which ultimately prove d successful.