Exploring nasopharyngeal microbiota profile in children affected by SARS-CoV-2 infection

The relationship between COVID-19 and nasopharyngeal (NP) microbiota has been investigated mainly in the adult population. We explored the NP profile of children affected by COVID-19, compared to healthy controls (CTRLs). NP swabs of children with COVID-19, collected between March and September 2020, were investigated at the admission (T0), 72 h to 7 days (T1), and at the discharge (T2) of the patients. NP microbiota was analyzed by 16S rRNA targeted-metagenomics. Data from sequencing were investigated by QIIME 2.0 and PICRUSt 2. Multiple machine learning (ML) models were exploited to classify patients compared to CTRLs. The NP microbiota of COVID-19 patients (N = 71) was characterized by reduction of α-diversity compared to CTRLs (N = 59). The NP microbiota of COVID-19 cohort appeared significantly enriched in Streptococcus, Haemophilus, Staphylococcus, Veillonella, Enterococcus, Neisseria, Moraxella, Enterobacteriaceae, Gemella, Bacillus, and reduced in Faecalibacterium, Akkermansia, Blautia, Bifidobacterium, Ruminococcus, and Bacteroides, compared to CTRLs (FDR < 0.001). Exploiting ML models, Enterococcus, Pseudomonas, Streptococcus, Capnocytopagha, Tepidiphilus, Porphyromonas, Staphylococcus, and Veillonella resulted as NP microbiota biomarkers, in COVID-19 patients. No statistically significant differences were found comparing the NP microbiota profile of COVID-19 patients during the time-points or grouping patients on the basis of high, medium, and low viral load (VL). This evidence provides specific pathobiont signatures of the NP microbiota in pediatric COVID-19 patients, and the reduction of anaerobic protective commensals. Our data suggest that the NP microbiota may have a specific disease-related signature since infection onset without changes during disease progression, regardless of the SARS-CoV-2 VL.

IMPORTANCE

Since the beginning of pandemic, we know that children are less susceptible to severe COVID-19 disease. A potential role of the nasopharyngeal (NP) microbiota has been hypothesized but to date, most of the studies have been focused on adults. We studied the NP microbiota modifications in children affected by SARS-CoV-2 infection showing a specific NP microbiome profile, mainly composed by pathobionts and almost missing protective anaerobic commensals. Moreover, in our study, specific microbial signatures appear since the first days of infection independently from SARS-CoV-2 viral load.

The 2020 International Alliance for the Control of Scabies Consensus Criteria for the Diagnosis of Scabies

BACKGROUND

Scabies is a common parasitic skin condition that causes considerable morbidity globally. Clinical and epidemiological research for scabies has been limited by a lack of standardization of diagnostic methods.

OBJECTIVES

To develop consensus criteria for the diagnosis of common scabies that could be implemented in a variety of settings.

METHODS

Consensus diagnostic criteria were developed through a Delphi study with international experts. Detailed recommendations were collected from the expert panel to define the criteria features and guide their implementation. These comments were then combined with a comprehensive review of the available literature and the opinion of an expanded group of international experts to develop detailed, evidence-based definitions and diagnostic methods.

RESULTS

The 2020 International Alliance for the Control of Scabies (IACS) Consensus Criteria for the Diagnosis of Scabies include three levels of diagnostic certainty and eight subcategories. Confirmed scabies (level A) requires direct visualization of the mite or its products. Clinical scabies (level B) and suspected scabies (level C) rely on clinical assessment of signs and symptoms. Evidence-based, consensus methods for microscopy, visualization and clinical symptoms and signs were developed, along with a media library.

CONCLUSIONS

The 2020 IACS Criteria represent a pragmatic yet robust set of diagnostic features and methods. The criteria may be implemented in a range of research, public health and clinical settings by selecting the appropriate diagnostic levels and subcategories. These criteria may provide greater consistency and standardization for scabies diagnosis. Validation studies, development of training materials and development of survey methods are now required. What is already known about this topic? The diagnosis of scabies is limited by the lack of accurate, objective tests. Microscopy of skin scrapings can confirm the diagnosis, but it is insensitive, invasive and often impractical. Diagnosis usually relies on clinical assessment, although visualization using dermoscopy is becoming increasingly common. These diagnostic methods have not been standardized, hampering the interpretation of findings from clinical research and epidemiological surveys, and the development of scabies control strategies. What does this study add? International consensus diagnostic criteria for common scabies were developed through a Delphi study with global experts. The 2020 International Alliance for the Control of Scabies (IACS) Criteria categorize diagnosis at three levels of diagnostic certainty (confirmed, clinical and suspected scabies) and eight subcategories, and can be adapted to a range of research and public health settings. Detailed definitions and figures are included to aid training and implementation. The 2020 IACS Criteria may facilitate the standardization of scabies diagnosis.

A systems genomics approach identifies SIGLEC15 as a susceptibility factor in recurrent vulvovaginal candidiasis

Candida vaginitis is a frequent clinical diagnosis with up to 8% of women experiencing recurrent vulvovaginal candidiasis (RVVC) globally. RVVC is characterized by at least three episodes per year. Most patients with RVVC lack known risk factors, suggesting a role for genetic risk factors in this condition. Through integration of genomic approaches and immunological studies in two independent cohorts of patients with RVVC and healthy individuals, we identified genes and cellular processes that contribute to the pathogenesis of RVVC, including cellular morphogenesis and metabolism, and cellular adhesion. We further identified SIGLEC15, a lectin expressed by various immune cells that binds sialic acid-containing structures, as a candidate gene involved in RVVC susceptibility. Candida stimulation induced SIGLEC15 expression in human peripheral blood mononuclear cells (PBMCs) and a polymorphism in the SIGLEC15 gene that was associated with RVVC in the patient cohorts led to an altered cytokine profile after PBMC stimulation. The same polymorphism led to an increase in IL1B and NLRP3 expression after Candida stimulation in HeLa cells in vitro. Last, Siglec15 expression was induced by Candida at the vaginal surface of mice, where in vivo silencing of Siglec15 led to an increase in the fungal burden. Siglec15 silencing was additionally accompanied by an increase in polymorphonuclear leukocytes during the course of infection. Identification of these pathways and cellular processes contributes to a better understanding of RVVC and may open new therapeutic avenues.

FRI0182 RISK FACTORS ASSOCIATED WITH RENAL INVOLVEMENT IN PRIMARY SJÖGREN’S SYNDROME: DATA FROM THE SPANISH SJÖGRENSER COHORT

Objectives:

To investigate the prevalence, risk factors, and effects of primary renal disease on morbidity and mortality in patients with primary Sjögren’s syndrome (pSS).

Methods:

All patients in the SJÖGRENSER (registry of adult SSp patients of the Spanish Society of Rheumatology, cross-sectional phase) cohort were retrospectively investigated for the presence of clinically significant renal involvement directly related to pSS activity.

Results:

Of the 437 patients investigated, 39 (9%) presented overt renal involvement during follow-up. Severe renal disease necessitating kidney biopsy was relatively rare (23%).

Renal involvement may complicate pSS at any time during the disease course and is associated with severe disease (indicated by higher scores of involvement, activity, and damage), systemic multiorgan involvement, and a higher frequency of lymphoma. Multivariate analysis showed that older age (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00–1.07), higher European League Against Rheumatism Sjogren’s Syndrome Disease Activity Index scores (OR 1.1, CI 1.03–1.18), serum anti-La/SSB positivity (OR 6.44, CI 1.36–30.37), and non-vasculitic cutaneous involvement (OR 8.64, 1.33–55.90) were independently associated with this complication.

Chronic renal failure developed in 23 of 39 patients (59%); only 1 of them progressed to end-stage renal disease necessitating renal replacement therapy. Patients with renal disease showed higher Sjögren’s syndrome disease damage index scores (SSDDI), higher rates of hospitalization due to disease activity and higher rates of clinically relevant comorbidities.

Conclusion:

Renal involvement is an uncommon complication in pSS that was observed in 9% of patients. Although categorized as a non-negligible comorbidity, this condition shows a favorable prognosis.

Disclosure of Interests:

None declared

A biological model of scabies infection dynamics and treatment informs mass drug administration strategies to increase the likelihood of elimination

Infections with Sarcoptes scabiei, or scabies, remain common in many disadvantaged populations. Mass drug administration (MDA) has been used in such settings to achieve a rapid reduction in infection and transmission, with the goal of eliminating the public health burden of scabies. While prevalence has been observed to fall substantially following such an intervention, in some instances resurgence of infection to baseline levels has occurred over several years. To explore the biology underpinning this phenomenon, we have developed a theoretical model of scabies life-cycle and transmission dynamics in a homogeneously mixing population, and simulate the impact of mass drug treatment strategies acting on egg and mite life cycle stages (ovicidal) or mites alone (non-ovicidal). In order to investigate the dynamics of the system, we first define and calculate the optimal interval between treatment doses. We calculate the probability of eradication as a function of the number of optimally-timed successive treatment doses and the number of years over which a program is run. For the non-ovicidal intervention, we first show that at least two optimally-timed doses are required to achieve eradication. We then demonstrate that while more doses over a small number of years provides the highest chance of eradication, a similar outcome can be achieved with fewer doses delivered annually over a longer period of time. For the ovicidal intervention, we find that doses should be delivered as close together as possible. This work provides a platform for further research into optimal treatment strategies which may incorporate heterogeneity of transmission, and the interplay between MDA and enhancement of continuing scabies surveillance and treatment strategies.

Association of a variable number tandem repeat in the NLRP3 gene in women with susceptibility to RVVC

Vaginal infections with Candida spp. frequently occur in women of childbearing age. A small proportion of these women experience recurrent vulvovaginal candidosis (RVVC), which is characterized by at least three episodes of infection in one year. In addition to known risk factors such as antibiotics, diabetes, or pregnancy, host genetic variation and inflammatory pathways such as the IL-1/Th17 axis have been reported to play a substantial role in the pathogenesis of RVVC. In this study, we assessed a variable number tandem repeat (VNTR) polymorphism in the NLRP3 gene that encodes a component of the inflammasome, processing the proinflammatory cytokines IL-1β and IL-18. A total of 270 RVVC patients and 583 healthy controls were analyzed, and increased diseases susceptibility was associated with the presence of the 12/9 genotype. Furthermore, functional studies demonstrate that IL-1β production at the vaginal surface is higher in RVVC patients bearing the 12/9 genotype compared to controls, whereas IL-1Ra levels were decreased and IL-18 levels remained unchanged. These findings suggest that IL-1β-mediated hyperinflammation conveyed by the NLRP3 gene plays a causal role in the pathogenesis of RVVC and may identify this pathway as a potential therapeutic target in the disease.

Electroporation Enhances Bleomycin Efficacy in Cats with Periocular Carcinoma and Advanced Squamous Cell Carcinoma of the Head

Background

Advanced carcinoma of the head represents a substantial health problem in cats for local control and overall survival.

Objectives

Evaluate the capability of electrochemotherapy (ECT) to improve bleomycin efficacy in cats with periocular carcinoma and advanced carcinoma of the head.

Animals

Twenty‐one cats with periocular carcinoma (17 squamous cell carcinoma [SCC] and 4 anaplastic carcinoma) and 26 cats with advanced SCC of the head.

Methods

Nonrandomized prospective controlled study. Periocular carcinoma cohorts: 12 cats were treated with bleomycin (15 mg/m²IV) coupled with ECT under anesthesia; 9 cats were treated with bleomycin alone. Advanced head SCC cohorts: 14 cats were treated with bleomycin (15 mg/m²IV) coupled with ECT administered under sedation; 12 control cats were treated with bleomycin alone. ECT treatments (2–8) were performed every other week until complete remission (CR) or tumor progression occurred.

Results

Toxicities were minimal and mostly treated symptomatically. Overall response rate in the ECT treated animals was 89% (21 Complete Response [CR] and 2 Partial Response [PR]) whereas controls had response rate of 33% (4 CR and 3 PR). Median time to progression in ECT group was 30.5 months, whereas in controls it was 3.9 months (P < .0001). Median time to progression for ECT cohorts was 24.2 months for periocular cohort and 20.6 in advanced head SCC cohort, respectively.

Conclusions

Electrochemotherapy is well tolerated for advanced SCC of the head in cats; its use may be considered among loco‐regional strategies for cancer therapy in sensitive body regions such as periocular region.

Fine-tuning of Th17 Cytokines in Periodontal Disease by IL-10

Periodontitis (PD) is a chronic disease caused by the host inflammatory response to bacteria colonizing the oral cavity. In addition to tolerance to oral microbiome, a fine-tuned balance of IL-10 levels is critical to efficiently mount antimicrobial resistance without causing immunopathology. Clinical and animal studies support that adaptive T-helper (Th) cytokines are involved in the pathogenesis of alveolar bone destruction in PD. However, it remains unclear what type of Th response is related to human PD progression and what role IL-10 has on this process. We addressed the contribution of IL-10 in limiting Th1 and Th17 inflammatory response in murine and human PD. Through a combination of basic and translational approaches involving selected cytokine-deficient mice as well as human genetic epidemiology, our results demonstrate the requirement for IL-10 in fine-tuning the levels of Th17 (IL-17A and IL-17F) cytokines in experimental and human PD. Of novelty, we found that IL-17F correlated with protection in murine and human PD and was positively regulated by IL-10. To our knowledge, this is the first demonstration of the protective role for IL-17F in PD, its positive regulation by IL-10, and the potential differential role for IL-17A and IL-17F in periodontal disease.

Immune resistance and tolerance to fungi

Fungal diseases represent an important paradigm in immunology, since they can result from either the lack of recognition or over-activation of the inflammatory response. Current understanding of the pathophysiology underlying fungal infections and diseases highlights the multiple cell populations and cell-signaling pathways involved in these complex conditions beyond the dysregulated chaos in which fungal infection and disease are perceived. A systems biology approach that integrates investigations of immunity at the systems-level is required to generate novel insights into this complexity and to decipher the dynamics of the host-fungus interaction. Recent advances in the immune response to fungi have highlighted the cellular and molecular mechanisms of immune adaptations that maintain homeostasis with the fungal biota and its possible rupture in fungal infections and diseases. Functionally distinct modules of immunity, i.e., resistance and tolerance, evolved for the achievement of the best-fitted host-fungus interaction in mammals, are now essential components of the host-fungus interaction in the vertebrate host.

Five years of experience in nocturnal enuresis and urinary incontinence in children: where we are and where we are going

BACKGROUND

Nocturnal enuresis (NE) is a very common pediatric disorder. The aim of this study was to evaluate the characteristics of patients with NE or urinary incontinence (UI) during a period of 5 years to increase the knowledge on these conditions and optimize their diagnosis and treatment.

METHODS

We enrolled 278 children with NE or UI referred to the pediatric nephrology ambulatory, 'A. Gemelli' University Hospital of Rome, from December 2006 to December 2011.

RESULTS

We observed that heredity, parasomnias, left-handedness, polythelia and constipation are correlated to NE and UI.

CONCLUSIONS

We wanted to clarify the definition of NE and UI and describe our experience on the main characteristics of these conditions by referring to the latest knowledge reported in the literature.

Immunotherapy of aspergillosis

Management of invasive aspergillosis in high-risk patients remains challenging. There is an increasing demand for novel therapeutic strategies aimed at enhancing or restoring antifungal immunity in immunocompromised patients. In this regard, modulation of specific innate immune functions and vaccination are promising immunotherapeutic strategies. Recent findings have also provided a compelling rationale for assessment of the contribution of the individual genetic profile to the immunotherapy outcome. Altogether, integration of immunological and genetic data may contribute to the optimization of therapeutic strategies exerting control over immune pathways, ultimately improving the management of fungal infections in high-risk settings.

IL-22 defines a novel immune pathway of antifungal resistance

The role of IL-17 and Th17 cells in immunity vs. pathology associated with the human commensal Candida albicans remains controversial. Both positive and negative effects on immune resistance have been attributed to IL-17/Th17 in experimental candidiasis. In this study, we provide evidence that IL-22, which is also produced by Th17 cells, has a critical, first-line defense in candidiasis by controlling the growth of infecting yeasts as well as by contributing to the host's epithelial integrity in the absence of acquired Th1-type immunity. The two pathways are reciprocally regulated, and IL-22 is upregulated under Th1 deficiency conditions and vice versa. Whereas both IL-17A and F are dispensable for antifungal resistance, IL-22 mediates protection in IL-17RA-deficient mice, in which IL-17A contributes to disease susceptibility. Thus, our findings suggest that protective immunity to candidiasis is made up of a staged response involving an early, IL-22-dominated response followed by Th1/Treg reactivity that will prevent fungal dissemination and supply memory.

Dynamics of extracellular release of Aspergillus fumigatus DNAand galactomannan during growth in blood and serum

Aspergillus fumigatus is the major cause of invasive aspergillosis (IA),a disease associated with high rates of morbidity and mortality in patientsundergoing treatment for haematological malignancies. This study investigated A. fumigatus growth in vitro and in a murine model of IA inorder to provide insights into the dynamics of extracellular DNA and galactomannan (GM)release and their relevance to early diagnosis of IA. Following inoculationof whole blood with 20 A. fumigatus conidia ml−1,DNA that corresponded to the inoculum could be detected by PCR but GM wasnot detected in plasma separated from the blood sample, indicating that thefungus did not grow in whole blood. The quantities of DNA detected by PCR,and GM, were proportional to the amount of fungal biomass present in vitro. Fungal DNA could be detected in the sera of mice experimentally infectedwith A. fumigatus with maximum detection in cyclophosphamide-treatedmice.

Chronic granulomatous disease

Chronic granulomatous disease is an inherited disorder of the NADPH oxidase characterized by severe bacterial and fungal infections and disordered inflammation. We propose that NADPH oxidase has a key role in regulating acute neutrophilic and T cell responses, which in turn restrains fungal growth and calibrates the inflammatory response to minimize injury and allergy. In this model, superoxide-induced activation of indoleamine 2,3-dioxygenase (IDO) is a central mechanism by which the optimal balance of antifungal host defense and immune tolerance occurs. This model is based on studies in mice and requires correlation in humans.