From the Guidelines
For a pregnant female with 30-40,000 CFU/ml of Staphylococcus haemolyticus in a urine culture, treatment is recommended as this represents a significant urinary tract infection, according to the 2019 clinical practice guideline for the management of asymptomatic bacteriuria by the Infectious Diseases Society of America 1.
Key Considerations
- The presence of Staphylococcus haemolyticus at this concentration indicates asymptomatic bacteriuria (ASB), which should be treated in pregnant women to prevent potential complications such as pyelonephritis, preterm labor, or low birth weight.
- The recommended treatment duration for ASB in pregnant women is 4–7 days of antimicrobial therapy, with the shortest effective course being preferred 1.
Treatment Options
- The preferred first-line treatment is not specified in the provided guidelines, but considering safety and efficacy during pregnancy, options like cephalexin or amoxicillin-clavulanate could be considered, with the caveat that antibiotic susceptibility testing is crucial to guide therapy.
- It's essential to complete the full course of antibiotics even if symptoms resolve quickly and to increase fluid intake to help flush bacteria from the urinary tract.
- A follow-up urine culture 1-2 weeks after completing treatment is necessary to confirm resolution of the infection.
Important Notes
- The guidelines emphasize the importance of screening for and treating ASB in pregnant women, despite some studies suggesting that nontreatment may be an acceptable option for selected low-risk women, highlighting the need for further evaluation in different populations 1.
- Antibiotic resistance patterns should be considered, and susceptibility testing is vital, especially if the initial treatment fails, to ensure appropriate adjustment of therapy.
From the Research
Staphylococcus Haemolyticus Infection
- Staphylococcus haemolyticus is a type of coagulase-negative staphylococci (CNS) that can cause infections, particularly in hospitalized patients 2.
- The susceptibility of S. haemolyticus to various antibiotics, including vancomycin, ciprofloxacin, daptomycin, and linezolid, has been studied 2, 3.
- According to a study published in 2011,15 out of 87 CNS strains isolated from blood cultures were identified as S. haemolyticus, and all of them were susceptible to daptomycin and linezolid 2.
- Another study published in 2016 found that all S. haemolyticus isolates were susceptible to linezolid and daptomycin, but 7.1% of the isolates were resistant to tigecycline 3.
Treatment of Staphylococcus Haemolyticus Infection
- The treatment of S. haemolyticus infection typically involves the use of antibiotics, such as vancomycin, daptomycin, or linezolid 2, 3.
- However, the choice of antibiotic may depend on the susceptibility of the isolate and the severity of the infection.
- In general, daptomycin and linezolid have been shown to be effective against S. haemolyticus, while vancomycin may be less effective due to the emergence of resistance 2, 3.
Pregnancy Considerations
- There is limited information available on the treatment of S. haemolyticus infection in pregnant women.
- However, it is generally recommended that pregnant women with bacterial infections be treated with antibiotics that are safe for use during pregnancy.
- The choice of antibiotic should be based on the susceptibility of the isolate and the severity of the infection, as well as the potential risks and benefits to the mother and the fetus.
Colony Forming Units (CFU)/ml
- The presence of 30-40,000 CFU/ml of S. haemolyticus in a pregnant female may indicate a significant infection that requires prompt treatment.
- The treatment of such an infection would typically involve the use of antibiotics, such as vancomycin, daptomycin, or linezolid, although the choice of antibiotic would depend on the susceptibility of the isolate and the severity of the infection 2, 3.