Activity of ceftriaxone and comparator agents against bacterial pathogens isolated from central nervous system (CNS) (meningeal) specimens: TSN Database USA 2000–2002
© BioMed Central Ltd 2003
Published: 3 March 2003
Meningeal infections are life-threatening and require immediate, parenteral treatment, often with β-lactams such as ceftriaxone (CTX). Using The Surveillance Database (TSN®) USA, we analyzed the susceptibility of pathogens frequently causing meningitis isolated from CNS specimens (including cerebral fluids and shunts).
We analyzed data (January 2000-October 2002) from The Surveillance Network (TSN®) Database USA, an electronic surveillance system that collects routine susceptibility test results from 326 hospital laboratories distributed throughout the USA. Data is the same data reported to physicians. Only data from non-repeat isolates from patients' CNS specimen sources were included in the analysis. NCCLS (2002) breakpoints (BPs) were used to interpret as susceptible (S) or resistant (R) (included CTX BPs for meningeal isolates of Streptococcus pneumoniae [SP]). The number of organism susceptibilities tested by drug varied.
A total of 10,436 organisms were isolated and the susceptibility tested. The relative incidence of key pathogens known to be frequently involved in meningitis was coagulase-negative Staphylococci (CoNS) (44.9%, n = 4688) (1.5%, n = 155 isolated from shunt infections), Staphylococcus aureus (SA) (10.7%, n = 1114), SP (5.6%, n = 580), Escherichia coli (EC) (2.5%, n = 266) (n = 11 isolated from shunt infections), S. agalactiae (SAG) (1.1%, n = 114), Haemophilus influenzae (HF) (0.7%, n = 71), and Neisseria meningitidis (NM) (0.3%, n = 26). 72.2% (n = 1046) of SA from all CNS sources and 33.8% (n = 145) of CoNS were involved in shunt infections, and were oxacillin-susceptible. Among oxacillin S SA, 99.4% of isolates tested were S to CTX (n = 179). Against all CNS sources, 85.3% (2.9% R) of SP and 100% of SAG were S to CTX. SP and SAG were 55.7% S (17.9% R) and 100% S to penicillin, respectively. All Gram-positive isolates tested were vancomycin S. Erythromycin R was detected in all streptococcal species. EC isolated from shunts were 100% (n = 6) S to CTX and 100% (n = 7) were S to imipenem. For HF from all CNS sources, 29.1% (n = 55) were ampicillin R but 100% (n = 45) CTX S. No interpretive criteria are defined for NM, although 39 isolates were identified during this time period.
Although oxacillin-resistant Staphylococci would require glycopeptide therapy, after 18 years of clinical use CTX retains very high efficacy against most isolates likely to cause meningeal infections, including SP and HF.