Ólafur Steingrímsson

Epidemiologic typing of Enterobacter sakazakii in two neonatal nosocomial outbreaks

Two unrelated hospital outbreaks of Enterobacter sakazakii, involving meningitis, bacteremia, and colonization of neonates, were investigated. In each of these outbreaks, E. sakazakii was isolated from both patients and dried infant formula. In previous outbreaks, the source and mode of transmission of E. sakazakii in neonatal infections was not determined. In this study, we used a combination of typing methods (plasmid analysis, antibiograms, chromosomal restriction endonuclease analysis, ribotyping, and multilocus enzyme electrophoresis) to evaluate the isolates from each outbreak as to their relatedness. The typing results differed among outbreaks, but in each one, patient and formula isolates shared the same typing pattern. The only exceptions were disk antibiograms, which often varied among colonies selected from each of the isolates. Plasmid analysis, chromosomal restriction endonuclease analysis, ribotyping, and multilocus enzyme electrophoresis all were effective as epidemiological typing methods for E. sakazakii, especially when used in combination. By using this typing scheme, we have confirmed that E. sakazakii from intrinsically contaminated dried infant formula was the source of neonatal infection.

Kingella kingae Infections in Paediatric Patients: 5 Cases of Septic Arthritis, Osteomyelitis and - Bacteraemia

Kingella kingae is a Gram-negative rod most often recognized as 1 of the organisms causing septic arthritis and osteomyelitis in children. Infection caused by K. kingae had not been diagnosed in Iceland until 5 cases were diagnosed at the Paediatric Department at the University Hospital of Iceland over a 1 year period. In this report we describe these 5 children with invasive infection caused by K. kingae (2 with septic arthritis, 1 with osteomyelitis, 1 with septic arthritis and osteomyelitis, and 1 with bacteraemia) and review the literature. All bacterial isolates were identified by the Bactec culture system.

Dose-Dependent Pharmacokinetics of Azlocillin Compared to Mezlocillin

The pharmacokinetics of azlocillin at intravenous doses of 1.0, 2.0 and 5.0 g and of 2.0 g mezlocillin were studied in a cross-over study on 10 healthy volunteers. The serum concentrations and total area under the serum curves for azlocillin increased more than expected from the multiples of the dose size. Likewise, the percentage of urinary excretion of an antibacterially active agent increased steadily with higher doses. The same applied to the serum half-life (t 1/2), whereas the total body clearance was reduced. All these characteristics are indicative of dose-dependent, i.e. capacity-limited pharmacokinetics. The t 1/2 was 0.89, 0.98, and 1.53 h for each dose. For 2.0 g mezlocillin, the serum values, urinary recovery, and t 1/2 were lower than the values after the same dose of azlocillin. The t 1/2 was 0.64 h. The total body clearance was 12,0, 9.2, and 6.4 liters/h for the three doses of azlocillin and 14.4 liters/h for 2. g mezlocillin. Dose dependence appears to be more pronounced with azlocillin than found previously with mezlocillin. Unchanged azlocillin and its biotransformation products are excreted more slowly than mezlocillin and its metabolites.

Lower genital tract infection with Chlamydia trachomatis and Neisseria gonorrhoeae in Icelandic women with salpingitis

In a study of 225 women with acute salpingitis verified by laparoscopy or laparotomy we investigated the prevalence of gonococcal and chlamydial infection in the lower genital tract. Neisseria gonorrhoeae was isolated from 18.9% of the women and Chlamydia trachomatis from 38.5%. Women with positive cultures were significantly younger (p less than 0.01) than those with negative cultures. A trend toward more severe inflammatory changes of the tubes was found in women with positive cultures compared with those with negative cultures. The majority of women with positive cultures stated they had only one sexual partner during the preceding 6 months. Single women had more partners (mean 1.9) than those cohabiting (mean 1.2). The ratio of single/multiple partners for women with Chlamydia was 2.5:1, and for those with gonorrhea 1:1 (p less than 0.05). Of the men, 60% could be examined and about 50% had positive cultures. Microbiologic investigation of both partners is necessary in order to prevent reinfection of the woman.

Clinical evaluation of an automated enzyme-linked fluorescent assay for the detection of chlamydial antigen in specimens from high-risk patients

A fully automated enzyme-linked fluorescent assay (ELFA) on the Vitek Immunodiagnostic Assay System (VIDAS CHL) was evaluated for the detection of chlamydial antigen in specimens from symptomatic and asymptomatic high-risk patients. The results were compared with those from McCoy cell culture and Chlamydiazyme with a blocking assay. False-positive VIDAS specimens were centrifuged and the pellet stained with direct fluorescent antibody (DFA). Of the 158 urine specimens, 52 (33%) were infected by Chlamydia trachomatis. The sensitivity and specificity of the VIDAS when compared with cell culture, DFA, and Chlamydiazyme were 75% and 96%, respectively, for urine specimens while the predictive value of a positive (PVP) and a negative (PVN) were 91% and 88%, respectively. Of the 245 urethral swabs, 75 (31%) were considered positive. The sensitivity and specificity were 71% and 92%, respectively, and the PVP and PVN were 80% and 87%, respectively. The sensitivity and specificity on the 108 cervical swabs, 22 of which were positive, were 95% and 95%, respectively, and PVP and PVN were 88% and 99%, respectively. Compared with Chlamydiazyme, the VIDAS was more sensitive on specimens from female patients and urine specimens, but less sensitive on urethral specimens from male patients.