European ST80 community-associated methicillin-resistant Staphylococcus aureus orbital cellulitis in a neonate

<p>Abstract</p> <p>Background</p> <p>Methicillin-resistant <it>Staphylococcus aureus</it> is a serious cause of morbidity and mortality in hospital environment, but also, lately, in the community. This case report is, to our knowledge, the first detailed description of a community-associated methicillin-resistant <it>S. aureus</it> ST80 orbital cellulitis in a previously healthy neonate. Possible predisposing factors of microbial acquisition and treatment selection are also discussed.</p> <p>Case presentation</p> <p>A 28-day-old Caucasian boy was referred to our hospital with the diagnosis of right orbital cellulitis. His symptoms included right eye proptosis, periocular edema and redness. Empirical therapy of intravenous daptomycin, rifampin and ceftriaxone was initiated. The culture of pus yielded a methicillin-resistant <it>S. aureus</it> isolate and the molecular analysis revealed that it was a Panton-Valentine leukocidine-positive ST80 strain. The combination antimicrobial therapy was continued for 42days and the infection was successfully controlled.</p> <p>Conclusions</p> <p>Clinicians should be aware that young infants, even without any predisposing condition, are susceptible to orbital cellulitis caused by community-associated methicillin-resistant <it>S. aureus.</it> Prompt initiation of the appropriate empirical therapy, according to the local epidemiology, should successfully address the infection, preventing ocular and systemic complications.</p

emm Types and clusters and macrolide resistance of pediatric group A streptococcal isolates in Central Greece during 2011-2017.

BACKGROUND:The surveillance of emm types and macrolide susceptibility of group A streptococcus (GAS) in various areas and time periods enhances the understanding of the epidemiology of GAS infections and may guide treatment strategies and the formulation of type-specific vaccines. Greece has emerged as a country with high macrolide use. However, studies suggest a gradual reduction in macrolide consumption after 2007. METHODS:During a 7-year period (2011-2017), 604 GAS isolates were recovered from consecutive children presenting with pharyngeal or nonpharyngeal infections in Central Greece; 517 viable isolates underwent molecular analysis, including emm typing. RESULTS:Isolates belonged to 20 different emm types (in decreasing order of prevalence: 1, 89, 4, 12, 28, 3, 75 and 6, accounting for 88.2% of total isolates). The emm types comprised 10 emm clusters (five most common clusters: E4, A-C3, E1, A-C4 and A-C5). The emm89 isolates were acapsular ('new clade'). Overall macrolide resistance rate was 15.4%, and cMLSB emerged as the predominant resistance phenotype (56.4%). The lowest annual resistance rates occurred in 2014 (13.1%), 2016 (5.5%) and 2017(8.0%) (P for trend = 0.002). Consumption of macrolide/lincosamide/streptogramin B declined by 22.6% during 2011-2017. Macrolide resistance and emm28 and emm77 types were associated (both P<0.001). The most frequently identified genetic lineages of macrolide-resistant GAS included emm28/ST52, emm77/ST63, emm12/ST36, emm89/ST101 and emm4/ST39. We estimated that 98.8% of the isolates belonged to emm types incorporated into a novel 30-valent M protein vaccine. CONCLUSIONS:In Central Greece during 2011-2017, the acapsular emm89 isolates comprised the second most prevalent type. Susceptibility testing and molecular analyses revealed decreasing GAS macrolide resistance rates, which may be attributed to the reduction in the consumption of macrolides and/or the reduced circulation of macrolide-resistant clones in recent years. Such data may provide valuable baseline information in targeting therapeutic intervention and the formulation of type-specific GAS vaccines

<i>emm</i> type distribution of the 338 macrolide-resistant group A streptococcal isolates with different macrolide resistance genotypes.

a<p>Number in parentheses, percent.</p>b<p><i>emm</i> type (no. of isolates): 3 (1), 6 (1), 49 (1), 102 (1), 106 (1).</p>c<p><i>emm</i> type (no. of isolates): 6 (1), 15 (1), 87 (1).</p>d<p><i>emm</i> type (no. of isolates): 25 (1).</p

<i>emm</i> type distribution of the macrolide-susceptible and macrolide-resistant group A streptococcal isolates.

a<p>Number in parentheses, percent.</p>b<p><i>emm</i> type (no. of isolates): 23 (1), 25 (1), 29 (2), 44 (1), 50 (1), 65 (1), 68 (1), 102 (1), 110 (2), 118 (1), PT3875 (1), ST3211 (1).</p>c<p><i>emm</i> type (no. of isolates): 15 (1), 25 (1), 49 (1), 102 (1), 106 (1).</p

Cumulative distribution of the <i>emm</i> types of the macrolide-susceptible (solid line) and the macrolide-resistant (dashed line) group A streptococcal (GAS) isolates, according to the types included in an experimental 26-valent GAS vaccine.

<p>Cumulative distribution of the <i>emm</i> types of the macrolide-susceptible (solid line) and the macrolide-resistant (dashed line) group A streptococcal (GAS) isolates, according to the types included in an experimental 26-valent GAS vaccine.</p

Macrolide-resistant group A streptococcal isolates.

<p>Annual frequencies of the 5 most common <i>emm</i> types. A significant yearly variation was observed in <i>emm</i>28 (<i>P</i><0.001), <i>emm</i>77 (<i>P</i><0.001) and <i>emm</i>4 (<i>P</i><0.005).</p

Macrolide resistance rate and resistance phenotypes among 2408 group A streptococcal isolates in Western Greece.

<p>Macrolide resistance rate and resistance phenotypes among 2408 group A streptococcal isolates in Western Greece.</p

Dynamics of pneumococcal carriage among day-care center attendees during the transition from the 7-valent to the higher-valent pneumococcal conjugate vaccines in Greece

Background: In Greece recently, higher-valent pneumococcal conjugate vaccines (PCVs) replaced the 7-valent (PCV7); the 10-valent (PCV10) became available in May 2009 and the 13-valent (PCV13) in June 2010. Methods: We investigated the nasopharyngeal colonization with Streptococcus pneumoniae in day-care center attendees in Athens and the prefecture of Viotia. Between December 2010 and June 2011, nasopharyngeal cultures were obtained 4 times, at enrollment and then every 6 to 8 weeks. Results: Among the 233 children, 225 (96.6%) had been vaccinated with >= 1 dose of PCV7. One tenth of the PCV7 vaccinated attendees had also received >= 1 dose of PCV13 or PCV10. During the 4 samplings, 358 isolates were recovered from a total of 874 samples. Of the 233 children, 183 (78.5%) were found to carry S. pneumoniae at least once. The overall serotype distribution among carriers was similar regardless of the time lapsed since the last PCV7 dose. A high frequency of 19A (17.1%) coincided with a low frequency of 19F (1.4%). Non-PCV13 serotypes accounted for 73.1% of the isolates; 23B, 15B/C, 16F, 21, 11A, 15A, 6C, 10A, 22F and 23A were the most common. Among attendees aged 24-59 months (median age 42 months), prolonged carriage of a non-PCV13 serotype was relatively common, mainly for 21 and 16F. One out of 4 cases of colonization with the prevalent non-PCV13 serotypes was followed by persistent carriage for 5 to 14 weeks. Conclusions: During this period of transition to the higher-valent PCVs in the day-care center setting, non-PCV13 serotypes dominated and exhibited prolonged colonization. The frequency and the duration of prolonged carriage tends to be increased, if sampling frequency increases and the carriage time before and after positive cultures is taken into consideration. Further studies regarding the fitness of the colonizing non-PCV13 serotypes will likely to be seen in the future. (C) 2014 Elsevier Ltd. All rights reserved

Seven-year surveillance of emm types of pediatric Group A streptococcal pharyngitis isolates in Western Greece

An experimental 26-valent M protein Group A streptococcal (GAS) vaccine has entered clinical studies. Pharyngeal GAS emm type surveillances in different areas and time-periods enhance the understanding of the epidemiology of GAS pharyngitis. Moreover, these surveillances, combined with the data on GAS invasive disease, can play a significant role in the formulation of multivalent type-specific vaccines. During a 7-year period (1999-2005), 2408 GAS isolates were recovered from consecutive children with pharyngitis in Western Greece. The overall macrolide resistance rate was 22.8%. Along the study period we noted a tendency towards significantly decreased rates of resistance, with the lowest rates occurring in 2002 (15.3%), 2003 (15%) and 2004 (16.7%). A random sample of isolates from each year, 338 (61.7%) of the 548 macrolide-resistant and 205 (11%) of the macrolide-susceptible, underwent molecular analysis, including emm typing. The 543 typed isolates had 28 different emm types. A statistically significant association was found between macrolide resistance and emm4, emm22 and emm77, whereas emm1, emm3, emm6, emm12, emm87 and emm89 were associated with macrolide susceptibility. A significant yearly fluctuation was observed in emm4, emm28 and emm77. The most common macrolide-resistant GAS were emm77 isolates harboring erm(A), either alone or in combination with mef(A), emm4 carrying mef(A), emm28 possessing erm(B), emm75 carrying mef(A), emm12 harboring mef(A) and emm22 carrying erm(A). We estimated that 82.8% of the isolates belonged to emm types included in the novel 26-valent M protein vaccine. The vaccine coverage rate was determined mainly by the increased frequency of nonvaccine emm4 isolates. A limited number of emm types dominated among macrolide-susceptible and macrolide-resistant GAS isolates. We observed seasonal fluctuations, which were significant for emm4, emm28 and emm77. This type of data can serve as baseline information if the novel 26-valent M protein GAS vaccine is introduced into practice