Search Results (7)

Psoriasis vulgaris is a T-cell-mediated skin disease that may involve an autoimmune response against melanocytes. It develops through still unexplained pathomechanisms. Streptococcal tonsillopharyngitis is a major trigger of psoriasis onset and relapses. HLA-C*06:02 is the main psoriasis risk gene. Here we find that B cells isolated from streptococci-infected tonsils or peripheral blood of HLA-C*06:02⁺ psoriasis patients stimulate an HLA-C*06:02-restricted melanocyte-reactive Vα3S1/Vβ13S1 T-cell receptor (TCR) from a lesional psoriatic CD8⁺ T cell clone in an IFN-γ-enhanced manner. Patients’ B cells furthermore induce proliferation of autologous blood CD8⁺ T cells. We identify several HLA-C*06:02-presented self-peptides in the immunopeptidomes we had isolated from four HLA-C*06:02 homozygous B-cell lines that stimulate the Vα3S1/Vβ13S1 TCR and differ from the melanocyte autoantigen recognized by this TCR. These data suggest that the proinflammatory environment of streptococcal tonsillopharyngitis may enable B cells to activate autoreactive CD8⁺ T cells that, owing to the polyspecificity of T-cell receptors, recognize several B-cell self-peptides presented by HLA-C*06:02 and subsequently cross-react against melanocytes in the skin, thereby triggering psoriasis. The capacity of B cells to stimulate a cross-reactive autoimmune response through HLA class I-presented B-cell peptides is a previously unknown mechanism in the induction of autoimmunity that could explain psoriasis onset and persistence. Full article

Background/Objectives: A common reason for a pediatrician’s visit is acute tonsillopharyngitis (ATR), which is usually caused by viruses. A dietary supplement comprising Pelargonium sidoides extract, honey, propolis, and zinc was proposed as an effective adjuvant for the management of respiratory tract infections. The study aimed to determine the efficacy of this dietary supplement in conjunction with standard of care (SoC) compared to SoC alone, in a pediatric population affected by ATR. Methods: This open randomized study (registered on ClinicalTrials.gov: NCT 04899401) involved three Romanian sites specialized in pediatric care. The primary endpoints were changes in Tonsillitis Severity Score and the number of patients failing to respond (evaluating the use of ibuprofen or high-dose paracetamol as a rescue medication). One hundred and thirty children, distributed into two groups, were enrolled and treated for six days. Results: The results showed an overall better performance in terms of efficacy of dietary supplement + SoC, compared to SoC alone, with lower total Tonsillitis Severity Score ratings on day 6 (p = 0.002) and lower sub-scores related to erythema and throat pain on day 6. No adverse events were reported. Investigators found compliance to be optimal. Conclusions: The administration of the dietary supplement + SoC in pediatric patients with ATR was found to be safe and superior to the administration of SoC alone in terms of efficacy. The results confirmed that the tested dietary supplement is an optimum effective adjuvant in the treatment of respiratory tract infections and is suitable for the daily clinical practice of pediatricians. Full article

Recently a resurgence of Streptococcus pyogenes infections has arisen, with concerns around the highly virulent M1_UK lineage. Our aim was to characterize S. pyogenes, the immune responses it causes, and to determine the presence of the M1_UK lineage in Sofia, Bulgaria. In our study, the infections were confirmed by culture testing or rapid antigen test. Identification was performed by MALDI-TOF and was followed up by antibiotic susceptibility testing (EUCAST). Virulence factors were identified using multiplex PCR and whole genome sequencing (WGS). Immune responses were measured through detection of serum complement levels, lymphocyte subsets, and cytokine profiling. Out of 82 children, 38 had scarlet fever and the rest had streptococcal pharyngitis. Strains were susceptible to penicillin (β-lactams), macrolides, clindamycin, tetracyclines, co-trimoxazole, fluoroquinolones, and linezolid. Superantigen profiles were identified: SpeA + SpeJ (45%), SpeC, and SpeI + SpeH (27.5% each). A novel Multilocus sequence typing (MLST) haplotype in the mutS gene (d90b) was found in four strains. The M1_UK lineage was detected for the first time in Bulgaria. We observed an increase in complement fractions C3 and C4 and a decrease in T lymphocytes. A significant increase in the levels of IFN-γ, IL-6, and IL-10 with corresponding reduction in IL-17A were revealed. In conclusion, the studied S. pyogenes strains were characterized by their susceptibility to antibiotics and the predominance of SpeA superantigen; for the first time in Bulgaria the presence of M1_UK and a novel SNP variation in the mutS gene (d90b) were found. A mixed pattern of pro- and anti-inflammatory immune responses in patients was observed. Full article

A high incidence of diphtheria cases in children in East Java province, Indonesia, has been observed since the beginning of this century. Despite many efforts, the outbreaks continue. This study aims to explain the high incidence of diphtheria in children in East Java province since 2013. This cross-sectional surveillance report-based study used data from 38 districts in East Java since 1 January 2013. Collected data included demographics, clinical information, additional examinations, immunization history, and close contact management. Over eleven years, there were 4009 diphtheria patients, of whom 2921 (72.86%) were under 18 years of age. Boys (59.77%) outnumbered girls, and the most common age category was >60–144 months (51.66%). Most cases had incomplete or zero immunization (76.16%). Tonsillopharyngeal diphtheria was the most common type (69.60%). The five top districts with the most cases were Surabaya, Sidoarjo, Kabupaten Blitar, Kota Malang, and Kabupaten Malang. The eleven-year case fatality rate (CFR) was 2.36% (69/2921). This study shows that diphtheria cases in children and adolescents in East Java have consistently been high, and low immunization coverage might still be the leading cause. There has also been a shift in the district distribution. Diphtheria outbreaks require complete and sustainable efforts, not just outbreak response immunizations. Full article

Physicians are currently finding products for pediatric respiratory diseases of viral etiology to reduce the inappropriate use of antibiotic therapy. This study evaluated PediaFlù (Pediatrica S.r.l.), a dietary supplement already on the market composed of honey, propolis, Pelargonium sidoides extract, and zinc (DSHPP), in children affected by acute tonsillopharyngitis (ATR). The open-label, randomized, and controlled study compared DSHPP + standard of care (SoC) versus SoC alone for six days. Children between 3 and 10 years with an ATR ≤ 48 h, a negative rapid test for beta-hemolytic Streptococcus, or a culture identification of nasal and/or pharyngeal exudates were included. A tonsillitis severity score (TSS) and the number of treatment failures (using ibuprofen or high-dose paracetamol as rescue medication) were the primary endpoints. DSHPP+ SoC showed better performance than SoC alone for TSS sub-scores: throat pain and erythema on day 6 (p < 0.001 and p < 0.05), swallowing (p < 0.01 on day 4), and TSS total score on days 4 and 6 (p < 0.05 and p < 0.001). Only one patient (SoC group) had treatment failure for ibuprofen administration. No adverse events were reported. DSHPP is an optimal adjuvant in the treatment of URTI and could potentially be useful in the daily clinical practice of paediatricians evaluating the correct antibiotic prescription. Full article

Hypervirulent Klebsiella pneumoniae (hvKp) is a novel pathotype that has been rarely described in Europe. This study characterizes a hvKp isolate that caused a community-acquired infection. The hypermucoviscous Klebsiella pneumoniae (K. pneumoniae) strain 18-0005 was obtained from a German patient with tonsillopharyngitis in 2017. Antibiotic susceptibility testing was performed and the genome was sequenced by Illumina and Nanopore technology. Whole genome data were analyzed by conducting core genome multilocus sequence typing (cgMLST) and single nucleotide polymorphism (SNP) analysis. Virulence genes were predicted by applying Kleborate. Phenotypic and whole genome analyses revealed a high similarity of the study isolate 18-0005 to the recently reported antibiotic-susceptible hvKp isolate SB5881 from France and the “ancestral” strain Kp52.145; both were assigned to the ST66-K2 lineage. Comparative genomic analysis of the three plasmids showed that the 18-0005 plasmid II differs from SB5881 plasmid II by an additional 3 kb integrated fragment of plasmid I. Our findings demonstrate the genetic flexibility of hvKp and the occurrence of a strain of the clonal group CG66-K2 in Germany. Hence, it emphasizes the need to improve clinical awareness and infection monitoring of hvKp. Full article

Leukocytoclastic small-vessel vasculitis of the skin (with or without systemic involvement) is often preceded by infections such as common cold, tonsillopharyngitis, or otitis media. Our purpose was to document pediatric (≤18 years) cases preceded by a symptomatic disease caused by an atypical bacterial pathogen. We performed a literature search following the Preferred Reporting of Systematic Reviews and Meta-Analyses guidelines. We retained 19 reports including 22 cases (13 females and 9 males, 1.0 to 17, median 6.3 years of age) associated with a Mycoplasma pneumoniae infection. We did not find any case linked to Chlamydophila pneumoniae, Chlamydophila psittaci, Coxiella burnetii, Francisella tularensis, or Legionella pneumophila. Patients with a systemic vasculitis (N = 14) and with a skin-limited (N = 8) vasculitis did not significantly differ with respect to gender and age. The time to recovery was ≤12 weeks in all patients with this information. In conclusion, a cutaneous small-vessel vasculitis with or without systemic involvement may occur in childhood after an infection caused by the atypical bacterial pathogen Mycoplasma pneumoniae. The clinical picture and the course of cases preceded by recognized triggers and by this atypical pathogen are indistinguishable. Full article