Pneumococci remain the main cause of complicated pediatric pneumonia in the post-pandemic era despite extensive pneumococcal vaccine use.

Nucleic acid amplification tests (NAATs) greatly enhance the capacity to identify the etiology of pediatric complicated pneumonia. However, the use of pneumococcal conjugate vaccines could reduce the importance of Streptococcus pneumoniae in pediatric complicated pneumonia with the potential emergence of other bacterial agents. Using an expanded NAAT in culture negative pleural fluid or empyema samples collected in 2010-2024 (n = 554) in Portugal, we show that S.

Rebound of pediatric invasive pneumococcal disease in Portugal after the COVID-19 pandemic was not associated with significant serotype changes.

Objectives: The COVID-19 pandemic led to the institution of public health measures in many countries which reduced respiratory infections. We aimed to identify and characterize changes in pediatric (<18 years) invasive pneumococcal disease (pIPD) in Portugal in 2018-2023.

Methods: pIPD cases were identified by culture and molecular methods and stratified by age and serotype.

Sustained increase of paediatric invasive infections dominated by M1 and diverse 12 isolates, Portugal, September 2022 to May 2023.

Since autumn 2022, observed numbers of paediatric invasive group A infections in Portugal (n = 89) were higher than in pre-COVID-19 seasons. Between September 2022 and May 2023, the dominant diagnoses were pneumonia (25/79), mostly with empyema (20/25), and sepsis (22/79). A number of cases required admission to intensive care (27/79) and surgery (35/79), and the case fatality rate was 5.

Continued Vaccine Breakthrough Cases of Serotype 3 Complicated Pneumonia in Vaccinated Children, Portugal (2016-2019).

We previously reported that despite the use of pneumococcal conjugate vaccines (PCVs), vaccine serotypes remained important causes of pneumonia with pleural effusion and empyema (pediatric complicated pneumococcal pneumonia [PCPP]). We cultured and performed PCR on 174 pleural fluid samples recovered from pediatric patients in Portugal from 2016 to 2019 to identify and serotype Streptococcus pneumoniae. Most PCPP cases ( = 87/98) were identified by PCR only.

Causing Skin and Soft Tissue Infections Are Enriched in the Recently Emerged 89 Clade 3 and Are Not Associated With Abrogation of CovRS.

Although skin and soft tissue infections (SSTI) are the most common focal infections associated with invasive disease caused by (Lancefield Group A streptococci - GAS), there is scarce information on the characteristics of isolates recovered from SSTI in temperate-climate regions. In this study, 320 GAS isolated from SSTI in Portugal were characterized by multiple typing methods and tested for antimicrobial susceptibility and SpeB activity. The and genes of isolates with no detectable SpeB activity were sequenced.

Pediatric Complicated Pneumonia Caused by Streptococcus pneumoniae Serotype 3 in 13-Valent Pneumococcal Conjugate Vaccinees, Portugal, 2010-2015.

Despite use of 7-valent pneumococcal conjugate vaccine, incidence of pleural effusion and empyema (pediatric complicated pneumococcal pneumonia [PCPP]) is reportedly increasing globally. We cultured and performed PCR on 152 pleural fluid samples recovered from pediatric patients in Portugal during 2010-2015 to identify and serotype Streptococcus pneumoniae. We identified only 17 cases by culture, but molecular methods identified S.

Consequences of the variability of the CovRS and RopB regulators among Streptococcus pyogenes causing human infections.

To evaluate the importance of covRS and ropB mutations in invasive disease caused by Group A Streptococci (GAS), we determined the sequence of the covRS and ropB genes of 191 isolates from invasive infections and pharyngitis, comprising a diverse set of emm types and multilocus sequence types. The production of SpeB and the activity of NAD glycohydrolase (NADase) and streptolysin S (SLS) were evaluated. The results support the acquisition of null covS alleles (predicted to eliminate protein function), resulting in downregulation of SpeB and upregulation of NADase and SLS, as a mechanism possibly contributing to higher invasiveness.

Automatic determination of NET (neutrophil extracellular traps) coverage in fluorescent microscopy images.

Motivation: Neutrophil extracellular traps (NETs) are believed to be essential in controlling several bacterial pathogens. Quantification of NETs in vitro is an important tool in studies aiming to clarify the biological and chemical factors contributing to NET production, stabilization and degradation. This estimation can be performed on the basis of fluorescent microscopy images using appropriate labelings.

Macrolide-resistant Streptococcus pyogenes: prevalence and treatment strategies.

Although penicillin remains the first-choice treatment for Streptococcus pyogenes infection, macrolides are important alternatives for allergic patients and lincosamides are recommended together with β-lactams in invasive infections. S. pyogenes may exhibit macrolide resistance because of active efflux (mef genes) or target modification (erm genes), the latter conferring cross resistance to lincosamides and streptogramin B.

Novel role of the antimicrobial peptide LL-37 in the protection of neutrophil extracellular traps against degradation by bacterial nucleases.

Neutrophil extracellular traps (NETs) have been described as a fundamental innate immune defence mechanism. They consist of a nuclear DNA backbone associated with different antimicrobial peptides (AMPs) which are able to engulf and kill pathogens. The AMP LL-37, a member of the cathelicidin family, is highly present in NETs.

Changes in Streptococcus pyogenes causing invasive disease in Portugal: evidence for superantigen gene loss and acquisition.

The emergence of highly virulent and successful Streptococcus pyogenes (group A streptococci - GAS) clones has been attributed to the exchange of virulence factors by lateral gene transfer mechanisms, which strongly contribute to genomic diversity. We characterized a collection of 191 GAS isolates recovered from normally sterile sites in Portugal during 2006-2009 and compared them to invasive isolates obtained during 2000-2005. Antimicrobial resistance rates did not change significantly between the two periods and were generally low.

Group A streptococci clones associated with invasive infections and pharyngitis in Portugal present differences in emm types, superantigen gene content and antimicrobial resistance.

Background: A few lineages of Group A streptococci (GAS) have been associated with a reemergence of severe invasive streptococcal disease in developed countries. However, the majority of the comparisons between invasive and non-invasive GAS isolates have been performed for collections of reduced genetic diversity or relied on limited typing information to distinguish clones. We characterized by several typing methods and compared a collection of 160 isolates recovered from normally sterile sites with 320 isolates associated with pharyngitis and recovered in the same time period in Portugal.

The Viriato study: update on antimicrobial resistance of microbial pathogens responsible for community-acquired respiratory tract infections in Portugal.

The Viriato study is a prospective, multicentre laboratory-based surveillance study of antimicrobial susceptibility in which 30 microbiology laboratories throughout Portugal are asked to isolate, identify and submit to a central laboratory for testing Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis responsible for community-acquired lower respiratory tract infections and Streptococcus pyogenes from tonsillitis. To monitor changes in antimicrobial resistance patterns of these frequent respiratory pathogens. Susceptibility was determined by disk diffusion (Kirby-Bauer) or using Etest strips following the Clinical and Laboratory Standards Institute guidelines.

Congenital adrenal hyperplasia: focus on the molecular basis of 21-hydroxylase deficiency.

Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder caused by defects in one of several steroidogenic enzymes involved in the synthesis of cortisol from cholesterol in the adrenal glands. More than 90% of cases are caused by 21-hydroxylase deficiency, and the severity of the resulting clinical symptoms varies according to the level of 21-hydroxylase activity. 21-Hydroxylase deficiency is usually caused by mutations in the CYP21A2 gene, which is located on the RCCX module, a chromosomal region highly prone to genetic recombination events that can result in a wide variety of complex rearrangements, such as gene duplications, gross deletions and gene conversions of variable extensions.

CYP21A2 mutations in Portuguese patients with congenital adrenal hyperplasia: identification of two novel mutations and characterization of four different partial gene conversions.

More than 90% of congenital adrenal hyperplasia (CAH) cases are caused by 21-hydroxylase deficiency. In this study, the CYP21 gene was genotyped in 56 Portuguese unrelated patients with clinical symptoms of 21-hydroxylase deficiency, in a total of 112 independent alleles. CYP21A2 mutations were identified in 99.