Staphylococcus lugdunensis

Staphylococcus lugdunensis
Scientific classification
Kingdom: Bacteria Phylum: Firmicutes Class: Cocci Order: Bacillales Family: Staphylococcaceae Genus: Staphylococcus Species: S. lugdunensis
Binomial name
Staphylococcus lugdunensis Freney et al. 1988

Staphylococcus lugdunensis is a member of the genus Staphylococcus, consisting of Gram-positive bacteria with spherical cells that appear in clusters. It was first described in 1988 and was recorded as a cause of serious human infections such as endocarditis, osteomyelitis, and septicaemia. It occurs as a commensal on human skin. In the past it was frequently misidentified as S. hominis, S. aureus, or other species.

S. lugdunensis may produce a bound coagulase (that is, the enzyme is bound to the cells), a property which it shares with S. aureus, but unlike S. aureus it does not produce a free coagulase. In the laboratory it can give a positive slide-coagulase test but a negative tube-coagulase test.

S. lugdunensis is fairly easy to identify because unlike the great majority of staphylococci it decarboxylates ornithine. (Very occasional strains of other species may do the same.)

Colonies of S. lugdunensis are usually hemolytic, sticky, yellow or tan and about 2-4 mm in diameter after a 48-hour incubation. They usually have a characteristic odour.

Antimicrobial therapy

• Staphylococcus lugdunensis treatment

• 1. Skin and soft tissue infections

• Preferred regimen: Oxacillin 1-2 g IV q4h for 1-2 weeks
• Note: Abscesses should be drained if possible.

• 2. Endocarditis

• 2.1 Native valve infectious endocarditis

• Preferred regimen (1): Vancomycin 15 mg/kg IV q12h (target trough concentration, 10 to 15 mcg/mL)
• Preferred regimen (for most patients with normal renal function) (2): Vancomycin 15 to 20 mg/kg (actual body weight) IV q8-12h -for trough concentration of 15 to 20 mcg/mL (minimum inhibitory concentration, 1 mcg/mL or less)
• Note: should consist of 6 weeks of parenteral beta-lactam therapy or Vancomycin (depending on susceptibility testing and beta-lactam hypersensitivity).

• 2.2 Prosthetic valve infective endocarditis

• Preferred regimen: Combination therapy including a beta-lactam (or Vancomycin) with an Aminoglycoside- Gentamicin 3 mg/kg/day in 1-3 divided doses and Rifampin 300 mg PO/IV q8h for at least 6 weeks
• Note (1): Combine with Vancomycin for the entire duration of therapy and Gentamicin for the first 2 weeks.
• Note (2): The Gentamicin should be administered for the first 2 weeks of therapy; the beta-lactam (or Vancomycin) and Rifampin should be continued for 6 weeks.
• Note (3): Surgery must be considered given the frequency of valvular compromise in the setting of Staphylococcus lugdunensis infective endocarditis.
• Note (4): The treatment of Staphylococcus lugdunensis pacemaker endocarditis includes antibiotic therapy as well as removal of the pacer system

• 3. Bacteremia

• Preferred regimen: Oxacillin 1-2 g IV q4h for 1-2 weeks

• Note (1): Bacteremia without endocarditis (often related to an intravascular catheter) appears to have a good prognosis.
• Note (2): For intravascular catheter-related Staphylococcus lugdunensis bacteremia, the catheter should be removed, followed by 14 days of antibiotics, provided that all of the following are applicable

• 2.1 The patient is not diabetic or immunosuppressed.
• 2.2 There is no prosthetic material, thrombophlebitis, infective endocarditis, evidence of metastatic infection.
• 2.3 The patient’s fever and bacteremia resolve within 72 hours after initiation of appropriate antibiotic therapy.

• 4. Prosthetic devices,

• Preferred regimen (1): Vancomycin 15 mg/kg IV q12h (target trough concentration, 10 to 15 mcg/mL)
• Preferred regimen (for most patients with normal renal function) (2): Vancomycin 15 to 20 mg/kg (actual body weight) IV q8-12h -for trough concentration of 15 to 20 mcg/mL (minimum inhibitory concentration, 1 mcg/mL or less)
• Preferred regimen (3): Daptomycin 6 mg/kg IV qd for 3 to 4 weeks
• Preferred regimen (4): Linezolid 600 mg IV q12h

• 5. Vertebral osteomyelitis, discitis

• Preferred regimen: Vancomycin 15 to 20 mg/kg IV q8-12h, not to exceed 2 g per dose

• 6. Septic arthritis in adults

• Preferred regimen: Vancomycin 15 mg/kg IV bd, not to exceed 2 g per 24 hours (unless cncentrations in serum are inappropriately low) for 4 weeks.