Capsule Expression and Genotypic Differences Among Staphylococcus aureus Isolates from Patients with Chronic or Acute steomyelitis.

LATTAR SM, TUCHSCHERR LP, CACCURI RL, CENTRÓN D, BECKER K, LONSO CA, BARBERIS C, MIRANDA G, BUZZOLA FR, VON EIFF C, AND SORDELLI DO.

INFECTION AND IMMUNITY

AMER SOC MICROBIOLOGY

Lugar: Washington; Año: 2009 vol. 77 p. 1968 - 1977

0019-9567

There is ample evidence that Staphylococcus aureus capsular polysaccharide (CP) promotes virulence. Loss of capsule expression, however, may lead to S. aureus persistence in a chronically infected host. This study was conducted to determine the relative prevalence of nonencapsulated S. aureus in patients with chronic and acute osteomyelitis. Only 76/118 (64%) S. aureus isolates from patients with osteomyelitis expressed CP, whereas all 50 isolates from blood cultures of patients with infections other than osteoarticular infections expressed CP (P 0.0001). A significantly higher prevalence of nonencapsulated S. aureus was found in patients with chronic osteomyelitis (53%) than in those with acute osteomyelitis (21%) (P 0.0046). S. aureus isolates obtained from multiple specimens from five of six patients with chronic osteomyelitis exhibited phenotypic (expression of CP,P Staphylococcus aureus capsular polysaccharide (CP) promotes virulence. Loss of capsule expression, however, may lead to S. aureus persistence in a chronically infected host. This study was conducted to determine the relative prevalence of nonencapsulated S. aureus in patients with chronic and acute osteomyelitis. Only 76/118 (64%) S. aureus isolates from patients with osteomyelitis expressed CP, whereas all 50 isolates from blood cultures of patients with infections other than osteoarticular infections expressed CP (P 0.0001). A significantly higher prevalence of nonencapsulated S. aureus was found in patients with chronic osteomyelitis (53%) than in those with acute osteomyelitis (21%) (P 0.0046). S. aureus isolates obtained from multiple specimens from five of six patients with chronic osteomyelitis exhibited phenotypic (expression of CP,P S. aureus persistence in a chronically infected host. This study was conducted to determine the relative prevalence of nonencapsulated S. aureus in patients with chronic and acute osteomyelitis. Only 76/118 (64%) S. aureus isolates from patients with osteomyelitis expressed CP, whereas all 50 isolates from blood cultures of patients with infections other than osteoarticular infections expressed CP (P 0.0001). A significantly higher prevalence of nonencapsulated S. aureus was found in patients with chronic osteomyelitis (53%) than in those with acute osteomyelitis (21%) (P 0.0046). S. aureus isolates obtained from multiple specimens from five of six patients with chronic osteomyelitis exhibited phenotypic (expression of CP,P S. aureus in patients with chronic and acute osteomyelitis. Only 76/118 (64%) S. aureus isolates from patients with osteomyelitis expressed CP, whereas all 50 isolates from blood cultures of patients with infections other than osteoarticular infections expressed CP (P 0.0001). A significantly higher prevalence of nonencapsulated S. aureus was found in patients with chronic osteomyelitis (53%) than in those with acute osteomyelitis (21%) (P 0.0046). S. aureus isolates obtained from multiple specimens from five of six patients with chronic osteomyelitis exhibited phenotypic (expression of CP,P S. aureus isolates from patients with osteomyelitis expressed CP, whereas all 50 isolates from blood cultures of patients with infections other than osteoarticular infections expressed CP (P 0.0001). A significantly higher prevalence of nonencapsulated S. aureus was found in patients with chronic osteomyelitis (53%) than in those with acute osteomyelitis (21%) (P 0.0046). S. aureus isolates obtained from multiple specimens from five of six patients with chronic osteomyelitis exhibited phenotypic (expression of CP,P P 0.0001). A significantly higher prevalence of nonencapsulated S. aureus was found in patients with chronic osteomyelitis (53%) than in those with acute osteomyelitis (21%) (P 0.0046). S. aureus isolates obtained from multiple specimens from five of six patients with chronic osteomyelitis exhibited phenotypic (expression of CP,P 0.0046). S. aureus isolates obtained from multiple specimens from five of six patients with chronic osteomyelitis exhibited phenotypic (expression of CP, -hemolysin, -hemolysin, slime, and the small-colony variant phenotype) and/or genotypic (pulsed-field gel electrophoresis and spa typing) differences. Nonencapsulated S. aureus was recovered from at least one specimen from each chronic osteomyelitis patient. Fourteen isolates obtained from two patients with acute osteomyelitis were indistinguishable from each other within each group, and all produced CP5. In conclusion, we demonstrated that nonencapsulated S. aureus is more frequently isolated from patients with chronic osteomyelitis than from those with acute osteomyelitis, suggesting that loss of CP expression may be advantageous to S. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selectionspa typing) differences. Nonencapsulated S. aureus was recovered from at least one specimen from each chronic osteomyelitis patient. Fourteen isolates obtained from two patients with acute osteomyelitis were indistinguishable from each other within each group, and all produced CP5. In conclusion, we demonstrated that nonencapsulated S. aureus is more frequently isolated from patients with chronic osteomyelitis than from those with acute osteomyelitis, suggesting that loss of CP expression may be advantageous to S. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selectionS. aureus is more frequently isolated from patients with chronic osteomyelitis than from those with acute osteomyelitis, suggesting that loss of CP expression may be advantageous to S. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selectionS. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selection-hemolysin, -hemolysin, slime, and the small-colony variant phenotype) and/or genotypic (pulsed-field gel electrophoresis and spa typing) differences. Nonencapsulated S. aureus was recovered from at least one specimen from each chronic osteomyelitis patient. Fourteen isolates obtained from two patients with acute osteomyelitis were indistinguishable from each other within each group, and all produced CP5. In conclusion, we demonstrated that nonencapsulated S. aureus is more frequently isolated from patients with chronic osteomyelitis than from those with acute osteomyelitis, suggesting that loss of CP expression may be advantageous to S. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selectionspa typing) differences. Nonencapsulated S. aureus was recovered from at least one specimen from each chronic osteomyelitis patient. Fourteen isolates obtained from two patients with acute osteomyelitis were indistinguishable from each other within each group, and all produced CP5. In conclusion, we demonstrated that nonencapsulated S. aureus is more frequently isolated from patients with chronic osteomyelitis than from those with acute osteomyelitis, suggesting that loss of CP expression may be advantageous to S. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selectionS. aureus is more frequently isolated from patients with chronic osteomyelitis than from those with acute osteomyelitis, suggesting that loss of CP expression may be advantageous to S. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selectionS. aureus during chronic infection. Our findings on multiple S. aureus isolates from individual patients allow us to suggest that selection