Comparative virulence of human isolates of coagulase-negative staphylococci tested in an infant mouse weight retardation model.
Human infections caused by coagulase-negative staphylococci have steadily increased in numbers and severity. Causes may be the use of artificial prostheses, immunocompromising chemotherapy and radiation therapy, and sophisticated surgical techniques, to name a few. Although the infectivity of coagulase-negative staphylococci as a group has been well documented for humans, attempts to study the pathogenesis of infections caused by individual species of coagulase-negative staphylococci have been hampered by the lack of an animal model that is not refractory to infection by these organisms. In the study reported here, a 2-day-old-mouse weight retardation test was used to assay the virulence of 60 clinical and reference strains of coagulase-negative staphylococci. These strains represented eight species of coagulase-negative staphylococci. The most virulent strains were demonstrated to be of the species Staphylococcus haemolyticus, S. saprophyticus, and S. epidermidis. The data further suggest that production of slime is a marker of virulence in S. epidermidis and that intraspecies differences in virulence occur.
Gunn
B A
BA
Department of Clinical Investigation, Brooke Army Medical Center, Fort Sam Houston, Texas 78234.
D000818:Animals; D000831:Animals, Newborn; D001426:Bacterial Proteins; D004195:Disease Models, Animal; D006023:Glycoproteins / Q000096:biosynthesis; D008074:Lipoproteins / Q000096:biosynthesis; D051379:Mice; D013203:Staphylococcal Infections / Q000382:microbiology*; D013210:Staphylococcus / Q000378:metabolism / Q000472:pathogenicity*; D013211:Staphylococcus aureus / Q000378:metabolism / Q000472:pathogenicity; D013212:Staphylococcus epidermidis / Q000378:metabolism / Q000472:pathogenicity; D014774:Virulence; D015430:Weight Gain
D001426:Bacterial Proteins; D006023:Glycoproteins; D008074:Lipoproteins; C025431:extracellular slime proteins, bacterial