Successful clearance of catheter-related bloodstream infection by antibiotic lock therapy using ampicillin.
OBJECTIVE
To report a case in which ampicillin was used successfully as lock therapy for a central venous intravascular catheter and to discuss the implications of ampicillin used in this modality.


METHODS
A 14-month-old girl with a long-term central venous catheter acquired a polymicrobial (Escherichia coli and Enterococcus durans) bloodstream infection. The central venous catheter was suspected as the source for the bacteremia based on the timing and number of positive blood cultures in relation to therapy with antibiotics. Antibiotic sensitivity testing revealed ampicillin monotherapy to be an ideal choice to treat both organisms. A combination of systemic therapy via a temporary catheter and antibiotic lock therapy of the central venous catheter was then instituted using ampicillin without anticoagulants. The patient tolerated this therapy without complications, and follow-up cultures demonstrated effective clearance of the bacteria.


CONCLUSIONS
Antibiotic lock therapy has been shown to be useful in the treatment of catheter-related bloodstream infections. However, many antibiotics have yet to be tested with this modality. Ampicillin, which is frequently used in the treatment of Enterococcus and E. coli infections, has not previously been reported as a single agent for lock therapy.


CONCLUSIONS
Ampicillin may be a useful agent with the relatively new modality of lock therapy for central venous catheters. Further studies are needed to demonstrate possible compatibility of this agent with anticoagulants, such as heparin, as well as its efficacy in treating catheter-related bloodstream infections.
Elwood
Robert L
RL
Department of Pediatric Infectious Disease, Walter Reed Army Hospital Center, Washington, DC 20307-5001, USA. Robert.Elwood@NA.AMEDD.ARMY.MIL
Spencer
Steven E
SE
D000667:Ampicillin / Q000008:administration & dosage / Q000627:therapeutic use*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000209:etiology / Q000382:microbiology; D002405:Catheterization, Central Venous / Q000009:adverse effects*; D004927:Escherichia coli Infections / Q000188:drug therapy* / Q000209:etiology / Q000382:microbiology; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000188:drug therapy* / Q000209:etiology / Q000382:microbiology; D006801:Humans; D007223:Infant; D016896:Treatment Outcome
D000900:Anti-Bacterial Agents; D000667:Ampicillin