Serious bacterial infections in hospitalized febrile infants aged 90 days or younger: the traditional combination of ampicillin and gentamicin is still appropriate.

BACKGROUND: A change in the bacterial epidemiology of infantile serious bacterial infection (SBI) has raised concerns regarding the appropriate empirical antibiotic therapy. OBJECTIVE: To describe the epidemiological features of SBI in febrile infants in order to elucidate the appropriate empirical regimens. METHODS: From 2005 to 2009, clinical and laboratory data were prospectively collected for all infants aged ≤ 90 days who were hospitalized for fever. RESULTS: Of the 1584 febrile infants who met the study criteria, 149 (9.4%) had a culture-proven SBI: urinary tract infection in 128 (86%), urinary tract infection with bacteraemia in 11 (7%), bacteraemia in 7 (5%), enteritis with bacteraemia in 2 (1.3%), and meningitis in 1 (0.7%). Ninety-one percent of cases were caused by Gram-negative bacteria, mostly Escherichia coli (72%). Among the causative Gram-positive bacteria were Enterococcus spp. (4%) and group B Streptococcus (0.7%); no cases of Listeria monocytogenes infection were identified. Sixty-one percent of the causative bacteria were resistant to ampicillin. According to in vitro susceptibility testing, the combination of ampicillin and gentamicin provided appropriate antibiotic coverage. CONCLUSIONS: Despite changes in the epidemiology of infantile SBI, the traditional combination of ampicillin and gentamicin is still appropriate for empirical treatment of febrile infants aged ≤ 90 days.

Penicillin and ceftriaxone susceptibility of Streptococcus pneumoniae isolated from cerebrospinal fluid of children with meningitis hospitalized in a tertiary hospital in Israel.

BACKGROUND: Streptococcus pneumoniae is now the predominant pathogen causing meningitis. The resistance of S. pneumoniae to penicillin and third-generation cephalosporins has grown steadily. OBJECTIVES: To assess the antibiotic susceptibility of S. pneumoniae isolated from the cerebrospinal fluid of children with meningitis, and determine the antibiotic regimen appropriate for suspected bacterial meningitis in Israel. METHODS: The study group included 31 children with 35 episodes of meningitis hospitalized from 1998 to 2006. S. pneumoniae isolates from the cerebrospinal fluid were tested for susceptibility to penicillin and ceftriaxone. RESULTS: Of the 35 isolates, 17 (48.6%) showed resistance to penicillin (minimum inhibitory concentration > or = 0.12 microg/ml). Only 3 isolates (8.6%) showed intermediate resistance to ceftriaxone (> or = 0.5 and < (2 microg/ml), and none showed complete resistance (MIC > or = 2 microg/ml). The rates of antibiotic resistance were higher in children who were treated with antibiotics prior to admission (penicillin 88.9% vs. 34.6%, P = 0.007; ceftriaxone 22.2% vs. 3.8%, P = 0.156). CONCLUSIONS: The rate of penicillin resistance is high in children with S. pneumoniae meningitis in Israel, especially in those treated with oral antibiotics prior to admission. Resistance to ceftriaxone is infrequent though not negligible. On the basis of these findings, current recommendations to empirically treat all children with suspected bacterial meningitis with ceftriaxone in addition to vancomycin until the bacterial susceptibility results become available are justified also in Israel.

Effect of benzathine penicillin treatment on antibiotic susceptibility of viridans streptococci in oral flora of patients receiving secondary prophylaxis after rheumatic fever.

OBJECTIVE: To assess the level of antibiotic resistance of viridans streptococci in the oral flora of children with a history of rheumatic fever, receiving long-term monthly intramuscular benzathine penicillin G prophylaxis. PATIENTS AND METHODS: Oral swabs from patients receiving monthly penicillin G prophylaxis for rheumatic fever were cultured and tested for viridans streptococci. The E-test was used to test susceptibility to penicillin G, clindamycin, clarithromycin and rifampin. Findings were compared with samples from healthy children who had not been exposed to antibiotic treatment for at least 2 months. RESULTS: Twenty-six patients and 20 control children were included in the study. Duration of intramuscular antibiotic treatment ranged from 5 months to 13.5 years. Sixty isolates of viridans streptococci species were obtained, with a similar distribution in the two groups. Intermediate resistance to penicillin (MIC 0.25-2 mg/L) was documented in 10 of the 32 isolates (31.2%) in the study group, and high resistance in none, compared to seven of 28 isolates (25%) with intermediate or high resistance in the control group (p=NS). All isolates in the study group and all but one in the control group were susceptible to clindamycin, and all isolates from both groups were susceptible to rifampin. One isolate (3.1%) in the study group and two (7.1%) in the control group were resistant to clarithromycin. CONCLUSION: Monthly Intramuscular penicillin prophylaxis has no effect on the antibiotic susceptibility of viridans streptococci in oral flora in children with a history of rheumatic fever, receiving secondary prophylaxis after rheumatic fever, regardless of the duration of treatment.