The Psoriasis Risk Allele HLA-C*06:02 Shows Evidence of Association with Chronic or Recurrent Streptococcal Tonsillitis

Effectiveness of antibiotic therapy for early recurrence of peritonsillar cellulitis and abscesses: A retrospective cohort study

OBJECTIVE

Short-term recurrence is common in patients with peritonsillar cellulitis and abscesses, leading to socioeconomic problems. Early switching from intravenous to oral antibiotics is feasible for treating certain diseases. However, reports on early switching and total antibiotic administration duration in peritonsillar cellulitis and abscesses are limited. This study aimed to determine the appropriate antibiotic therapy duration and examine the impact of early oral switch therapy on peritonsillar cellulitis and abscesses.

METHODS

We retrospectively identified 98,394 patients who received antibiotic therapy during hospitalization for peritonsillar cellulitis and abscesses between July 1, 2010, and December 31, 2019, using the Japanese Diagnosis Procedure Combination database.

RESULTS

Propensity score matching analysis revealed no significant between-group difference in the rehospitalization rate (early oral switch therapy and long intravenous therapy: 1.7 % [198 of 11,621] vs. 2.0 % [234 of 11,621], odds ratio [OR] 0.84, 95 % confidence interval [CI] 0.70-1.02). A long total duration of antibiotic therapy (reference: 1-9 days) was associated with a low risk of rehospitalization (10-14 days: OR 0.86, 95 % CI 0.78-0.95; 15+ days: OR 0.51, 95 % CI 0.38-0.66).

CONCLUSION

Early oral switch therapy may be a viable option for treating patients with peritonsillar cellulitis and abscesses in good condition who can tolerate oral intake. No less than 10 days of antibiotic therapy is desirable.

Triggers for the onset and recurrence of psoriasis: a review and update

Psoriasis is an immune-mediated inflammatory skin disease, involving a complex interplay between genetic and environmental factors. Previous studies have demonstrated that genetic factors play a major role in the pathogenesis of psoriasis. However, non-genetic factors are also necessary to trigger the onset and recurrence of psoriasis in genetically predisposed individuals, which include infections, microbiota dysbiosis of the skin and gut, dysregulated lipid metabolism, dysregulated sex hormones, and mental illness. Psoriasis can also be induced by other environmental triggers, such as skin trauma, unhealthy lifestyles, and medications. Understanding how these triggers play a role in the onset and recurrence of psoriasis provides insights into psoriasis pathogenesis, as well as better clinical administration. In this review, we summarize the triggers for the onset and recurrence of psoriasis and update the current evidence on the underlying mechanism of how these factors elicit the disease. Video Abstract.

Intranasal streptococcal infection exacerbates psoriasis-like dermatitis via the induction of skin tissue-resident memory T cells

Recurrent streptococcal tonsillitis exacerbates psoriasis. Studies have indicated that T cells responding to streptococcal antigens in the skin are involved in the pathogenesis of the disease. However, a direct link between streptococcal tonsillitis and psoriasis has not been evidenced. In the present study, the impact of intranasal (i.n.) streptococcal infection on psoriasis was investigated using the imiquimod (IMQ) psoriasis mouse model. The results showed that repeated i.n. infection with group A Streptococcus (GAS) induced a robust and persistent Th17 response in the nasal-associated lymphoid tissue (NALT) and exacerbated IMQ-mediated psoriatic skin lesions. ELISpot and flow cytometry analyses revealed that GAS-reactive tissue-resident memory T cells (T_RM) were present in the skin of GAS-infected mice and produced IL-17/IL-23 axis cytokines in response to IMQ, compared to mice uninfected with GAS. In addition, i.n. infection with Streptococcus pneumoniae (Sp), a pathogen not associated with the development of psoriasis, also induced a persistent Th17 response in NALT but did not exacerbate IMQ-induced psoriatic inflammation nor elicited Sp-specific T cells in the skin. The results provide in vivo evidence that GAS-associated psoriasis is dependent on the skin GAS-specific T_RM cells induced by GAS nasopharyngeal infection and can be later activated by environmental triggers, leading to psoriatic inflammation. Reducing the reservoir of Th17 cells, which are source of skin T_RM cells, may constitute a promising treatment for psoriasis.

Inflammatory and infectious upper respiratory diseases associate with 41 genomic loci and type 2 inflammation

Inflammatory and infectious upper respiratory diseases (ICD-10: J30-J39), such as diseases of the sinonasal tract, pharynx and larynx, are growing health problems yet their genomic similarity is not known. We analyze genome-wide association to eight upper respiratory diseases (61,195 cases) among 260,405 FinnGen participants, meta-analyzing diseases in four groups based on an underlying genetic correlation structure. Aiming to understand which genetic loci contribute to susceptibility to upper respiratory diseases in general and its subtypes, we detect 41 independent genome-wide significant loci, distinguishing impact on sinonasal or pharyngeal diseases, or both. Fine-mapping implicated non-synonymous variants in nine genes, including three linked to immune-related diseases. Phenome-wide analysis implicated asthma and atopic dermatitis at sinonasal disease loci, and inflammatory bowel diseases and other immune-mediated disorders at pharyngeal disease loci. Upper respiratory diseases also genetically correlated with autoimmune diseases such as rheumatoid arthritis, autoimmune hypothyroidism, and psoriasis. Finally, we associated separate gene pathways in sinonasal and pharyngeal diseases that both contribute to type 2 immunological reaction. We show shared heritability among upper respiratory diseases that extends to several immune-mediated diseases with diverse mechanisms, such as type 2 high inflammation.

The impact of external factors on psoriasis

Psoriasis is one of the most common chronic inflammatory skin diseases, constituting a significant health and socioeconomic problem. Despite numerous therapeutic options, the results of treatment very often remain insufficient. It is extremely important to remember that many external factors impact the effectiveness of therapy. This article discusses the importance of emollients in therapy and the influence of infectious agents and injuries on the course of psoriasis. Understanding the above-mentioned factors in the treatment of psoriasis is critical to achieve satisfactory therapeutic effects.

Skin Barrier Dysregulation in Psoriasis

The skin barrier is broadly composed of two elements-a physical barrier mostly localised in the epidermis, and an immune barrier localised in both the dermis and epidermis. These two systems interact cooperatively to maintain skin homeostasis and overall human health. However, if dysregulated, several skin diseases may arise. Psoriasis is one of the most prevalent skin diseases associated with disrupted barrier function. It is characterised by the formation of psoriatic lesions, the aberrant differentiation and proliferation of keratinocytes, and excessive inflammation. In this review, we summarize recent discoveries in disease pathogenesis, including the contribution of keratinocytes, immune cells, genetic and environmental factors, and how they advance current and future treatments.

A high-resolution HLA reference panel capturing global population diversity enables multi-ancestry fine-mapping in HIV host response

Fine-mapping to plausible causal variation may be more effective in multi-ancestry cohorts, particularly in the MHC, which has population-specific structure. To enable such studies, we constructed a large (n = 21,546) HLA reference panel spanning five global populations based on whole-genome sequences. Despite population-specific long-range haplotypes, we demonstrated accurate imputation at G-group resolution (94.2%, 93.7%, 97.8% and 93.7% in admixed African (AA), East Asian (EAS), European (EUR) and Latino (LAT) populations). Applying HLA imputation to genome-wide association study data for HIV-1 viral load in three populations (EUR, AA and LAT), we obviated effects of previously reported associations from population-specific HIV studies and discovered a novel association at position 156 in HLA-B. We pinpointed the MHC association to three amino acid positions (97, 67 and 156) marking three consecutive pockets (C, B and D) within the HLA-B peptide-binding groove, explaining 12.9% of trait variance.

HLA-Cw1 and Psoriasis

Psoriasis is a chronic inflammatory skin condition with regional and ethnic differences in its prevalence and clinical manifestations. Human leukocyte antigen (HLA)-Cw6 is the disease allele conferring the greatest risk to psoriasis, but its prevalence is lower in Asian individuals. Recent studies have found associations between HLA-Cw1 and some Asian populations with psoriasis, especially Southern Chinese. HLA-Cw6 was associated with type I early-onset psoriasis, guttate psoriasis, Koebner phenomenon, and better response to methotrexate, interleukin (IL)-12/23, IL-17, and IL-23 targeting drugs. In contrast, HLA-Cw1 positivity has been associated with erythrodermic psoriasis, pustular psoriasis, and the axial type of psoriatic arthritis. Furthermore, HLA-Cw1 was more frequently associated with high-need patients who did not respond to conventional therapies. No known trigger factor nor autoantigen has been identified for HLA-Cw1 positivity. However, HLA-Cw1 has been linked to some viral agents. For example, cytotoxic T lymphocytes recognize multiple cytomegalovirus pp65-derived epitopes presented by HLA alleles, including HLA-C*01:02. In addition, cytomegalovirus can lead to severe exacerbation of psoriatic skin disease. The proposed interaction between viral infection, HLA-Cw1, and psoriasis is through the killer cell immunoglobulin-like receptors of natural killer cells. Given the diverse nature of psoriasis pathogenesis and the difference in HLA-Cw prevalence in different racial groups, more studies are needed to confirm the role of HLA-Cw1 in psoriasis.

Paediatrics: how to manage pharyngitis in an era of increasing antimicrobial resistance

The goal of this narrative review of pharyngitis is to summarize the practical aspects of the management of sore throat in children in high- and middle-income countries. A traditional review of the literature was performed. Most cases of pharyngitis are viral and self-limited, although rarely viral pharyngitis due to Epstein–Barr leads to airway obstruction. Bacterial pharyngitis is usually due to group A streptococcus (GAS), occurs primarily in children aged 5–15 years, and presents as sore throat in the absence of rhinitis, laryngitis or cough. Again, most cases are self-limited; antibiotics hasten recovery by only 1–2 days. Guidelines vary by country, but antibiotics are commonly recommended for proven GAS pharyngitis as they may prevent rare but severe complications, in particular rheumatic fever (RF). In this era of antimicrobial stewardship, it should be extremely rare that antibiotics are prescribed for presumed GAS pharyngitis until GAS has been detected. Even with proven GAS pharyngitis, it is controversial whether children at low risk for RF should routinely be prescribed antibiotics as the number needed to treat to prevent one case of RF is undoubtedly very large. When treatment is offered, the antibiotics of choice are penicillin or amoxicillin as they are narrow spectrum and resistance resulting in clinical failure is yet to be documented. A 10-day oral course is recommended as shorter courses appear to be less likely to clear carriage of GAS. However, the evidence that one needs to clear carriage to prevent RF is low quality and indirect.

Gut-Skin Axis: Current Knowledge of the Interrelationship between Microbial Dysbiosis and Skin Conditions

The microbiome plays an important role in a wide variety of skin disorders. Not only is the skin microbiome altered, but also surprisingly many skin diseases are accompanied by an altered gut microbiome. The microbiome is a key regulator for the immune system, as it aims to maintain homeostasis by communicating with tissues and organs in a bidirectional manner. Hence, dysbiosis in the skin and/or gut microbiome is associated with an altered immune response, promoting the development of skin diseases, such as atopic dermatitis, psoriasis, acne vulgaris, dandruff, and even skin cancer. Here, we focus on the associations between the microbiome, diet, metabolites, and immune responses in skin pathologies. This review describes an exhaustive list of common skin conditions with associated dysbiosis in the skin microbiome as well as the current body of evidence on gut microbiome dysbiosis, dietary links, and their interplay with skin conditions. An enhanced understanding of the local skin and gut microbiome including the underlying mechanisms is necessary to shed light on the microbial involvement in human skin diseases and to develop new therapeutic approaches.

Microbial-derived antigens and metabolites in spondyloarthritis

Spondyloarthritis (SpA) is a group of chronic, immune-mediated, inflammatory diseases affecting the bone, synovium, and enthesis. Microbiome, the community of microorganisms that has co-evolved with human hosts, plays a pivotal role in human health and disease. This invisible "essential organ" supplies the host with a myriad of chemicals and molecules. In turn, microbial metabolites can serve as messengers for microbes to communicate with each other and in the cross-talk with host cells. Gut dysbiosis in SpA is associated with altered microbial metabolites, and an accumulated body of research has contributed to the understanding that changes in intestinal microbiota can modulate disease pathogenesis. We review the novel findings from human and animal studies to provide an overview of the contribution of individual microbial metabolites and antigens to SpA.

Tonsillectomy and the subsequent risk of psoriasis: A nationwide population-based cohort study

BACKGROUND

Tonsillectomy has been suggested as an intervention to resolve psoriasis.

OBJECTIVE

This study aimed to investigate the subsequent risk of psoriasis in patients who received tonsillectomy.

METHODS

We used data from the Taiwan National Health Insurance Research Database. The tonsillectomy group (case group) and the tonsillectomy-free group (comparison group) were matched at a ratio of 1:4 by demographic data, comorbidities, medical confounders, and the index date. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

We identified 2021 patients as the case group and matched 8084 individuals as the comparison group. The adjusted HR (aHR) of psoriasis was 0.43 (95% CI, 0.22-0.87; P < .05). The study population is composed of a mainly male (65%) and young population (mostly younger than 50 years). Notably, patients with rheumatoid arthritis increased the risk of psoriasis (aHR, 3.97; 95% CI, 1.17-13.48; P < .05). In our stratification analysis, the risk of psoriasis decreased in almost all subgroups.

LIMITATION

Our database did not include information on genome and the subtypes of psoriasis.

CONCLUSION

Our study showed a decreased risk of psoriasis in the tonsillectomy group after adjustment for baseline characteristics, comorbidities, and medical confounders compared with the reference group.

Streptococci and the complement system: interplay during infection, inflammation and autoimmunity

Streptococci are a broad group of Gram-positive bacteria. This genus includes various human pathogens causing significant morbidity and mortality. Two of the most important human pathogens are Streptococcus pneumoniae (pneumococcus) and Streptococcus pyogenes (group A streptococcus or GAS). Streptococcal pathogens have evolved to express virulence factors that enable them to evade complement-mediated attack. These include factor H-binding M (S. pyogenes) and pneumococcal surface protein C (PspC) (S. pneumoniae) proteins. In addition, S. pyogenes and S. pneumoniae express cytolysins (streptolysin and pneumolysin), which are able to destroy host cells. Sometimes, the interplay between streptococci, the complement, and antistreptococcal immunity may lead to an excessive inflammatory response or autoimmune disease. Understanding the fundamental role of the complement system in microbial clearance and the bacterial escape mechanisms is of paramount importance for understanding microbial virulence, in general, and, the conversion of commensals to pathogens, more specifically. Such insights may help to identify novel antibiotic and vaccine targets in bacterial pathogens to counter their growing resistance to commonly used antibiotics.

Genetics of leprosy: today and beyond

Leprosy is a chronic infectious disease of the skin and peripheral nerves that presents a strong link with the host genetic background. Different approaches in genetic studies have been applied to leprosy and today leprosy is among the infectious diseases with the greatest number of genetic risk variants identified. Several leprosy genes have been implicated in host immune response to pathogens and point to specific pathways that are relevant for host defense to infection. In addition, host genetic factors are also involved in the heterogeneity of leprosy clinical manifestations and in excessive inflammatory responses that occur in some leprosy patients. Finally, genetic studies in leprosy have provided strong evidence of pleiotropic effects between leprosy and other complex diseases, such as immune-mediated or neurodegenerative diseases. These findings not only impact on the field of leprosy and infectious diseases but also make leprosy a good model for the study of complex immune-mediated diseases. Here, we summarize recent genetic findings in leprosy susceptibility and discuss the overlap of the genetic control in leprosy with Parkinson's disease and inflammatory bowel disease. Moreover, some limitations, challenges, and potential new avenues for future genetics studies of leprosy are also discussed in this review.

[Influence of tonzillektomy on the course of psoriasis]

Here, we performed the comprehensive review of the peer-reviewed literature of the effect of chronic foci of streptococcal infection on the course of skin psoriasis, as well as an assessment of the effectiveness of tonsillectomy on the course of this pathology. A PubMed, Web of Science and Google Scholar search were performed with the keywords 'psoriasis' AND 'tonsillectomy' OR 'tonsillitis' OR 'streptococcal infection'. The reviewers identified and evaluated 197 reports published prior to August 2018, of which 153 were excluded from further analysis after review of titles and/or abstracts including four duplicate studies from the same authors in the same patient groups. In total, 44 reports were used and included in the review (including original studies, a description of clinical cases, literature reviews). Analysis of the original studies showed that the effectiveness of tonsillectomy in patients with psoriasis is from 11.4 to 78.6%. Among clinical cases, the rate was 20-100%. We did not conduct a meta-analysis and use the statistical methods because of the heterogeneity of the data. Data were analysed using a descriptive approach. Most studies came from Russia, USA, Japan. However, multiple limitations in the studies do not allow final conclusions about the effectiveness of tonsillectomy in patients with psoriasis.