Clinical and microbiological features associated with group B Streptococcus bone and joint infections, France 2004-2014.

This study describes the clinical and microbiological features associated with group B Streptococcus (GBS) bone and joint infections (BJIs). It was a retrospective analysis of adult cases of GBS BJIs reported to the French National Reference Center for Streptococci from January 2004 to December 2014. Clinical data and GBS molecular characteristics are reported. Strains were collected from 163 patients. The most frequent comorbidities were: solid organ cancer (n = 21, 21%) and diabetes mellitus (n = 20, 20%). The main infection sites were knee (47/155 = 30%) and hip (43/155 = 27%), and occurred on orthopedic devices in 71/148 cases (48%). CPS III (n = 47, 29%), Ia (n = 26, 16%) and V (n = 40, 25%) were predominant. Resistance to erythromycin, clindamycin and tetracycline was detected in 55/163 (34%), 35/163 (21%) and 132/163 (81%) strains, respectively. The most frequent sequence types were ST-1 (n = 21, 25%), ST-17 (n = 17, 20%) and ST-23 (n = 11, 13%). The rate of resistance to erythromycin was 0% for ST-17 strains, 52% (n = 11) for ST-1 and 44% (n = 7) for ST-23 (p < 0.001). GBS bone and joint infections predominantly occur in patients aged >50 years and/or with comorbidities such as cancer and diabetes mellitus. CPS type distribution and MLST are very similar to that of other adult GBS invasive infections.

Reactivity of (1→3)-ß-d-glucan assay in bacterial bloodstream infections.

To diagnose invasive fungal infections, the detection of (1 → 3)-ß-d-glucan in serum has shown variable specificity, depending on the targeted population. Several circumstances for false-positive results of beta-glucan tests have been identified, among which are severe bacterial infections. In this study, we measured (1 → 3)-ß-d-glucan by the Fungitell test in the serum of 62 patients (one serum sample tested per patient) for whom invasive fungal infection was not suspected: 19 control subjects and 43 patients with bacteraemia. The test was interpretable for 58 sera: all 19 control subjects had negative beta-glucan test; among the 39 bacteraemic patients, we report 16 false-positive results. For the 22 patients undergoing bacteraemia due to Gram-negative bacilli, we observed 13 false-positive results (59%). Among the 17 patients with bloodstream infection involving Gram-positive cocci, three false-positive tests were recorded, but none in the eight cases of Streptococcus pneumoniae bacteraemia. Statistical analysis showed that beta-glucan levels were significantly higher in patients with Gram-negative bacilli bloodstream infection in comparison to those with bacteraemia due to Gram-positive cocci. These results were independent from other previously described causes for false-positive beta-glucan tests. These data might help physicians to interpret positive beta-glucan detection when an invasive fungal infection is suspected, especially for patients with bacterial infections.

Virulence factors (aerobactin and mucoid phenotype) in Klebsiella pneumoniae and Escherichia coli blood culture isolates.

We examined the presence of two virulence factors in 241 blood isolates of Klebsiella pneumoniae from patients hospitalized during 1989 and 1990 in 7 French hospitals, and 125 blood isolates of Escherichia coli from one hospital. Aerobactin was scored phenotypically and genotypically with an intragenic DNA probe of 2 kb. The mucoid phenotype was assessed by culture on trypticase soy agar and by genotypic analysis (intragenic DNA probe of 235 bp). Only 6% K. pneumoniae isolates were aerobactin-positive with no significant variation according to geographical location while 20% of K. pneumoniae isolates displayed the mucoid phenotype, with a significant variation according to hospital. Aerobactin was always associated with the mucoid phenotype. The frequency of aerobactin production but not mucoid phenotype (14%) was higher among E. coli isolates (48%). They harbored two types of large plasmids. Intraperitoneal injection into mice of 10(3) cfu of K. pneumoniae producing both virulence factors demonstrated that capsular serotype K2 was the more virulent K23 and K28.

Spontaneous abortions during the second trimester of gestation.

To determine the factors causing spontaneous abortions, 422 consecutive second-trimester abortions and the corresponding clinical data were studied prospectively. All of the fetuses and placentas were referred to a single pathologist and microbiological cultures were carried out in 205 of these cases. One hundred twenty-one medically included abortions were used as controls for the interpretation of the investigations relating to infection. According to the degree of maceration, two groups could be isolated and seemed to represent different diseases and mechanisms of spontaneous abortions. In the largest group (78.6%) without long intrauterine retention, one explanation could be given for 85% of these cases. Ascending infections occurred through unruptured membranes, whether or not they were associated with obstetric complications. The second group (21.4%) included severely macerated fetuses where a cause of death could only be determined in 44% of the cases that had a predominance of fetal abnormalities and maternal factors.

Incidence of two virulence factors (aerobactin and mucoid phenotype) among 190 clinical isolates of Klebsiella pneumoniae producing extended-spectrum beta-lactamase.

Because outbreaks of multiple-resistant Klebsiella pneumoniae isolates producing extended-spectrum beta-lactamases were recently observed in French hospitals, the presence of virulence factors was examined for (i) phenotype by bioassay for aerobactin production and by culture for the mucoid phenotype, and (ii) genotype using intragenic probes of respectively 2-kb BglII and 235-bp BamHI-BglII fragments and dot-blotting among 190 unreplicated K. pneumoniae clinical isolates issued from 25 French hospitals and producing different types of extended-spectrum beta-lactamases (TEM-related enzymes: TEM-3, TEM-4, CAZ-1, CAZ-2, TEM-8, or SHV-related enzymes: SHV-2, SHV-3, SHV-4). Only 3.7% and 7% of K. pneumoniae isolates produced aerobactin and mucoid phenotypes respectively, unrelated to type of beta-lactamase. Only 2% had both factors. No discordance was reported according to the detection method tested. The low prevalence of such virulence factors seems to indicate they were not involved in dissemination of nosocomial K. pneumoniae isolates producing an extended-spectrum beta-lactamase.

[Multicenter study of 435 yeast strains isolated from 116,000 hemocultures]. / Etude multicentrique de 435 souches de levures isolées de 116000 hémocultures.

During a multicentric study on the diagnosis of yeast septicemia, 5 blood culture media have been compared. 435 yeast strains have been isolated from 116,372 blood cultures received during year 1989 in the mycological laboratories of 5 university hospitals from east of France. The results show that Candida albicans is always the first septicemia agent with 52% of yeasts isolation from blood. C. parapsilosis comes next with 17%, then C. glabrata, 6.2%. The average delay of yeasts isolation is 2.3 days for Bactec NR and Sabouraud media, 3.7 days for other bacteriological media. Compared with polyvalent media, Sabouraud diphasic medium is significantly the best for yeasts isolation. It is recommended to add chloramphenicol in the medium, to culture 10 ml of blood and to keep blood cultures for at least 8 days, better 15 days.

[Animal bites. Epidemiology and infection risks]. / Morsures d'animaux. Epidémiologie et risques infectieux.

A review of 5,116 cases of animal bites (587 of which were studied prospectively) has shed some light on their epidemiological aspects and on the risk of infection they carry. It has also led to a more objective assessment of the real effect of the therapeutic and prophylactic measures usually applied in such cases. The most frequent wounds are those of the hands and face, the former rising an infectious problem, the latter a predominantly cosmetic problem. The overall risk of infection is 30 per cent, but it is increased, notably as regards pasteurellosis, in the case of cat bite. Precise and simple rules concerning the prevention of this risk cannot easily be given, but it seems that the systematic antibiotic treatment initially prescribed has not clearly proved effective. Similarly, early sutures do not significantly increase the risk of infection.