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.

Highly virulent M1 Streptococcus pyogenes isolates resistant to clindamycin.

CONTEXT: Emm1-type group A Streptococcus (GAS), or Streptococcus pyogenes, is mostly responsible for invasive infections such as necrotizing fasciitis (NF) and streptococcal toxic shock syndrome (STSS). The recommended treatment of severe invasive GAS infections is a combination of clindamycin and penicillin. Until 2012, almost all emm1 isolates were susceptible to clindamycin. OBJECTIVES: We aimed to identify the phenotypic and genotypic characteristics of emm1 GAS clone resistant to clindamycin. METHODS: GAS strains were characterized by emm sequence typing, detection of genes encoding pyrogenic exotoxins or superantigens. Cluster analysis was performed by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). Antibiotic susceptibility was assessed using disk diffusion and resistance genes were detected by PCR. RESULTS: A total of 1321 GAS invasive isolates were analyzed between January 2011 and December 2012. The overall number of invasive isolates resistant to clindamycin was 52 (3.9%); seven of them were emm1 isolates. All isolates had the same genomic markers: macrolide resistance due to the presence of the erm(B) gene, emm subtype 1.0, the same toxin or superantigen profile, PFGE pattern and sequence type. CONCLUSION: This is the first description of highly virulent GAS emm1 isolates resistant to clindamycin in France. This article strengthens the need for monitoring the epidemiology of invasive GAS strains as they could lead to changes in treatment guidelines.

Group B streptococcus neonatal invasive infections, France 2007-2012.

Streptococcus agalactiae (group B streptococcus (GBS)) is the leading cause of invasive infections among newborns in industrialized countries, with two described syndromes: early-onset disease (EOD) and late-onset disease (LOD). Since the introduction in many countries of intrapartum antibioprophylaxis (IAP), the incidence of EOD has dramatically decreased, whereas that of LOD remains unchanged. We describe the clinical and bacteriological characteristics of 438 GBS neonatal invasive infections notified to the French National Reference Centre for Streptococci in France from 2007 to 2012. Clinical data were retrieved from hospitalization reports or questionnaires. Capsular type, assignment to the hypervirulent clonal complex (CC)17 and antibiotic susceptibility profiles were determined. One hundred and seventy-four (39.7%) and 264 (60.3%) isolates were responsible for EOD, including death in utero, and LOD, respectively. EOD was associated with bacteraemia (n = 103, 61%) and LOD with meningitis (n = 145, 55%). EOD was mainly due to capsular polysaccharide (CPS) III isolates (n = 99, 57%) and CPS Ia isolates (n = 40, 23%), and CPS III isolates were responsible for 80% (n = 211) of LOD cases. CC17 accounted for 80% (n = 121) of CPS III isolates responsible for meningitis (n = 151; total cases of meningitis, 188). Bad outcome risk factors were low gestational age and low birthweight. LOD represents almost 60% of cases of neonatal GBS disease in France and other countries in which IAP has been implemented. This observation reinforces the need to develop new prevention strategies targeting CC17, which is predominant in GBS neonatal infections.

IgM peak independently predicts treatment-free survival in chronic lymphocytic leukemia and correlates with accumulation of adverse oncogenetic events.

We examined the significance of IgM peaks in chronic lymphocytic leukemia (CLL), including its association with newly reported MYD88, BIRC3, NOTCH1 and SF3B1 mutations. A total of 27, 25, 41 and 57 patients with monoclonal IgM or IgG peaks (IgM and IgG groups), hypogammaglobulinemia (Hypo-γ group) and normal immunoglobulin serum levels (normal-γ group) were, respectively, included. IgM peaks were mainly associated with Binet stage C and the del(17p). Biased usage of IGHV3-48 was shared by both IgM and IgG groups. IGHV3-74 and IGHV4-39 gene rearrangements were specific for IgM and IgG peaks, respectively. SF3B1, NOTCH1, MYD88 and BIRC3 mutation frequencies were 12%, 4%, 2% and 2%, respectively, being over-represented in IgM, IgG and Hypo-γ groups for SF3B1, and being equal between normal-γ and IgM groups for MYD88. Overall, 76%, 87%, 49% and 42% of cases from IgM, IgG, Hypo-γ and normal-γ groups had at least one intermediate or poor prognosis genetic marker, respectively. By multivariate analysis, IgM peaks were associated with shorter treatment-free survival independently from any other univariate poor prognosis biological parameters, including IgG peaks, Hypo-γ, IGHV status, SF3B1 mutations, cytogenetics and lymphocytosis. Therefore, as with IgG peaks, IgM peaks aggravated the natural course of CLL, with increased accumulation of adverse genetic events.

[Epidemiology of Streptococcus pyogenes invasive diseases in France (2007-2011)]. / Épidémiologie des infections invasives à Streptococcus pyogenes (France 2007-2011).

Group A Streptococcus (GAS) is a human pathogen responsible for a wide range of clinical manifestations. An increase of GAS invasive infections has been described since the mid 1980s. To study the French epidemiology of invasive infections (i) we characterized all GAS invasive strains received at the French National Reference Center for streptococci (CNR-Strep) between 2007 and 2011; (ii) we analyzed the epidemiological data on the corresponding strains. For each strain, emm genotype, superantigen genes and antibiotics susceptibility were determined. Among the 2 603 non redundant invasive GAS strains, 65.1 % (n=1 695) were isolated from blood culture. A streptococcal toxic shock syndrome (STSS) was described in 16.4 % (n=428) of cases, mostly associated with necrotizing fasciitis (NF), pleuropulmonary or osteoarticular infections (p ≤0.001). The case fatality rate was 10.6 %. A total of 102 different emm genotypes were identified. Three emm genotypes predominated, reaching nearly 60 % of the strains: emm 1 (26.7 %), emm 28 (16.4 %), and emm 89 (12.8 %). The proportion of each emm genotype varied according to the year and the age of patients. Among those < 15 years old, the three main genotypes were emm 1 (36.8 %), emm 12 (12.9 %) and emm 4 (9.5 %). The distribution of superantigen genes (SpeA, SpeC and Ssa) was restricted to several emm genotypes. Between 2007 and 2011, the rate of macrolides resistant GAS strains decreased from 7.8 to 5.5 %. emm 1 strains are still the most common especially in most severe clinical manifestations including STSS and NF.

Invasive group B streptococcal infections in adults, France (2007-2010).

Group B streptococcus (GBS) has emerged as an important cause of invasive infection in adults. Here, we report the clinical and microbiological characteristics of 401 non-redundant GBS strains causing adult invasive infections collected during a 4-year period (2007-2010). Bacteraemia without focus (43.4%) and bone and joint infections (18.7%) were the main clinical manifestations. The distribution of capsular polysaccharide (CPS) type showed that types Ia, III, and V accounted for 71.8% of all strains. Resistance to erythromycin increased from 20.2% in 2007 to 35.3% in 2010, and was mainly associated with CPS type V harbouring the erm(B) resistant determinant.