A novel treatment strategy using continuous local antibiotic perfusion: A case series study of a refractory infection caused by hypervirulent Klebsiella pneumoniae.

BACKGROUND: Conventional topical antimicrobial therapy cannot maintain a constant local concentration, resulting in uncontrolled infection and complications. We propose continuous local antibiotic perfusion (CLAP), which can maintain a constant appropriate local antibiotic concentration for a long time with less invasiveness and complications. CLAP is clearly different from traditional treatment because it uses negative pressure to direct the continuously infused antibiotic solution to the center of infection and excrete it outside the body. This study aimed to demonstrate the effectiveness of CLAP by presenting cases in which even refractory bone and soft-tissue infections caused by the hypervirulent Klebsiella pneumoniae (hvKp) could be cured without significant tissue loss and dysfunction. METHODS: This study is a case series in which four patients with limb infection due to hvKp were treated by CLAP. hvKp was defined by a positive string test. The therapy included intra-soft-tissue antibiotic perfusion and intramedullary antibiotic perfusion. Gentamicin (60 mg/50 cc) was infused continuously through dual-lumen tubes and bone marrow needles at low-flow rates (2 mL/h). Negative pressure was used to collect the antimicrobial solution and eliminate the dead space. RESULTS: The infection was controlled in all four patients after a mean period of 44.3 days. The mean maximum blood concentration of gentamicin was 1.6 µg/dL, and no cases of renal dysfunction or ototoxicity occurred. After CLAP, wound closure was required in two patients and iliac bone grafting was required in one patient. As sequelae, there were one case of osteoarthritis and one case of higher brain dysfunction due to hypoxia. CONCLUSIONS: Our results suggest that intractable hvKp infections can be controlled by CLAP. CLAP may give us the option to directly control local infections with less systemic complications. Therefore, it is considered a valuable treatment for further basic and clinical research, and this research report may be a first step.