Ertapenem Combined With Anti-Staphylococcal Beta-Lactam Therapy for the Treatment of Persistent Staphylococcus Aureus Bacteremia in a Child With Vertebral Osteomyelitis.

Staphylococcus aureus infection is one of the most common and serious infections that arises in children and is associated with high morbidity. S. aureus is the leading cause of acute hematogenous osteomyelitis in children. In the absence of concerns regarding resistance to methicillin, an anti-staphylococcal isoxazolyl penicillin, such as oxacillin or nafcillin, is the drug of choice for treatment of S. aureus osteomyelitis. However, first-generation cephalosporins, such as cefazolin, can also be used. There are limited antimicrobial options available for osteomyelitis and persistent or intermittent bacteremia when surgical intervention for source control is not indicated or feasible. Hence, there is a need to improve our knowledge of synergistic antimicrobial combinations to guide clinical practice and improve outcomes, particularly among children. We present the case of an 11-year-old child with persistence of acute hematogenous vertebral osteomyelitis with discitis and bacteremia, despite appropriate treatment with an anti-staphylococcal beta-lactam. Blood cultures were sterilized, and symptoms resolved after the addition of ertapenem 1 g daily for 7 days. To our knowledge, this is the first report of using ertapenem in combination with an anti-staphylococcal beta-lactam to specifically treat persistent methicillin-susceptible S. aureus (MSSA) vertebral osteomyelitis with bacteremia. Similar success has been reported using this combination to treat adults with persistent MSSA bacteremia and preterm low-birth-weight infants with late-onset neonatal sepsis; hence, our report provides further support for the benefit of this combination in staphylococcal infections.