From the Guidelines
For 2 out of 2 blood cultures positive for Staphylococcus haemolyticus, I recommend initiating treatment with vancomycin at a loading dose of 25-30 mg/kg followed by 15-20 mg/kg every 8-12 hours (adjusted for renal function), with target trough levels of 15-20 μg/mL. Alternatively, daptomycin 6-10 mg/kg IV daily can be used 1. Treatment duration should be 14 days for uncomplicated bacteremia or 4-6 weeks if endocarditis or other deep-seated infection is present. S. haemolyticus is a coagulase-negative staphylococcus that is often multidrug-resistant, particularly to methicillin and other beta-lactams. It frequently causes healthcare-associated infections, especially in patients with indwelling devices or catheters.
Key Considerations
- Source control is essential, so any potentially infected catheters should be removed if possible 1.
- Infectious disease consultation is recommended to guide management.
- Echocardiography should be considered to rule out endocarditis, particularly in patients with persistent bacteremia, prosthetic valves, or other risk factors 1.
- Blood cultures should be repeated to document clearance of bacteremia.
Treatment Approach
- Vancomycin is an appropriate antimicrobial to use empirically until identification and antimicrobial sensitivities are available 1.
- In countries without high rates of MRSA, an anti-staphylococcal beta-lactam antimicrobial could be the first option.
- However, in severe illness, neutropenic or otherwise immunocompromised patients and those with a femoral catheter, additional empiric coverage for Gram-negative bacilli is reasonable 1.
Duration of Therapy
- Treatment duration should be 14 days for uncomplicated bacteremia or 4-6 weeks if endocarditis or other deep-seated infection is present 1.
- A 4–6-week antibiotic course should be administered if there is persistent bacteremia or fungemia (i.e., >72 h in duration) after hemodialysis catheter removal or for patients with endocarditis or suppurative thrombophlebitis 1.
From the Research
Staphylococcus haemolyticus Blood Cultures
- 2 out of 2 blood cultures positive for Staphylococcus haemolyticus indicate a possible infection with this bacterium 2, 3.
- Staphylococcus haemolyticus is a type of coagulase-negative staphylococci (CNS) that can cause infections, particularly in hospitalized patients 2.
- The susceptibility of Staphylococcus haemolyticus to various antibiotics, including vancomycin, ciprofloxacin, daptomycin, and linezolid, has been studied 2, 4.
Antibiotic Susceptibility
- Staphylococcus haemolyticus has shown resistance to vancomycin, with some studies reporting a high frequency of strains with reduced susceptibility to vancomycin 2, 4.
- Daptomycin has been shown to be effective against Staphylococcus haemolyticus, with no resistance observed in some studies 2, 3.
- Linezolid has also been used to treat Staphylococcus haemolyticus infections, but resistance has been reported 2, 3.
- The use of daptomycin and linezolid in combination has been reported to be effective in treating Staphylococcus haemolyticus infections 3.
Treatment Options
- Vancomycin is often used as a first-line treatment for Staphylococcus haemolyticus infections, but its effectiveness may be limited by resistance 2, 5.
- Daptomycin may be a suitable alternative for the treatment of Staphylococcus haemolyticus infections, particularly in cases where vancomycin resistance is suspected 2, 3, 5.
- The choice of antibiotic treatment should be guided by susceptibility testing and clinical judgment 6.