Characterization of dysbiosis of the conjunctival microbiome and nasal microbiome associated with allergic rhinoconjunctivitis and allergic rhinitis

Nasal, dermal, oral and indoor dust microbe and their interrelationship in children with allergic rhinitis

BACKGROUND

Allergic rhinitis (AR) subjects might have their microenvironment changed due to pathogenesis and living environment. Whether the nasal microbe in AR children differs from healthy subjects and how it interplays with dermal, oral and indoor dust microbe needs to be elucidated.

METHODS

In this case-control study, we analyzed and compared the bacterial characterization and associations in nasal, dermal, oral swab samples and dust samples in 62 children with physician-diagnosed AR(cases) and 51 age- and gender-matched healthy ones with no history of allergic diseases(controls). Full-length 16S rRNA sequencing(swabs) and shotgun metagenomics(dust) were applied. Bacterial diversity, composition, abundance difference characteristics and fast expectation-maximization for microbial source tracking(FEAST) analysis were performed and compared between cases and controls.

RESULTS

The α-diversity of dust microorganisms in AR was lower than that in control group (P = 0.034), and the β-diversity indices of microorganisms in nasal cavity (P = 0.020), skin (P = 0.001) and dust (P = 0.004) were significantly different from those in control group. At species levels, a total of 10, 15, 12, and 15 bacterial species were differentially enriched in either cases or controls in nasal, dermal, oral, and dust samples, respectively(Linear Discriminant Analysis(LDA) score > 2, P < 0.05). Staphylococcus epidermidis was the single species simultaneously more abundant in nasal, dermal and dust samples in AR children. By FEAST analysis, 8.85% and 10.11% of S. epidermidis in AR dermal and dust samples came from nasal cavity. These proportions were significantly higher than those in controls (2.70% and 3.86%) (P < 0.05). The same significantly higher transfer proportions(P < 0.05) were observed for Staphylococcus aureus enriched in the nasal cavity in AR children. Classification models by random forest regression at species levels showed, bacterial species enriched in indoor dust, nasal and dermal samples had substantial power in distinguishing AR children from healthy ones, with the highest power in the dust samples (AUC = 0.88) followed by nasal(AUC = 0.81) and dermal ones(AUC = 0.80).

CONCLUSIONS

Our study presented the microbial enrichment characteristics in AR children both in the living environment(dust) and body sites exposed to environment through inhalation(nasal cavity), contact(skin) and ingestion(oral cavity) pathways, respectively. Nasal S.epidermidis and S.aureus had dominant influences on dust and other body sites in AR children.

Proteomic scrutiny of nasal microbiomes: implications for the clinic

INTRODUCTION

The nasal cavity is the initial site of the human respiratory tract and is one of the habitats where microorganisms colonize. The findings from a growing number of studies have shown that the nasal microbiome is an important factor for human disease and health. 16S rRNA sequencing and metagenomic next-generation sequencing (mNGS) are the most commonly used means of microbiome evaluation. Among them, 16S rRNA sequencing is the primary method used in previous studies of nasal microbiomes. However, neither 16S rRNA sequencing nor mNGS can be used to analyze the genes specifically expressed by nasal microorganisms and their functions. This problem can be addressed by proteomic analysis of the nasal microbiome.

AREAS COVERED

In this review, we summarize current advances in research on the nasal microbiome, introduce the methods for proteomic evaluation of the nasal microbiome, and focus on the important roles of proteomic evaluation of the nasal microbiome in the diagnosis and treatment of related diseases.

EXPERT OPINION

The detection method for microbiome-expressed proteins is known as metaproteomics. Metaproteomic analysis can help us dig deeper into the nasal microbiomes and provide new targets and ideas for clinical diagnosis and treatment of many nasal dysbiosis-related diseases.

[Current aspects of vernal and atopic keratoconjunctivitis]

BACKGROUND

Vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) are complex and rare diseases. Thus, their diagnosis and treatment are often a challenge.

OBJECTIVE

Discussion on the epidemiology, new pathogenetic concepts, interesting clinical findings, diagnostic possibilities and new treatment options and their side effects in severe ocular allergies. Analysis of the presentation of VKC in the internet.

MATERIAL AND METHODS

Evaluation of recent review articles, original publications, and case reports on the topics of VKC and AKC over the past 5 years.

RESULTS

Ocular allergies have significantly increased over the last decades. Recent concepts discussed in the pathogenesis of VKC and AKC are the role of the local and gut microbiome as well as the influence of neuroinflammation. Keratoconus is significantly more common in patients with VKC and AKC compared to the normal population. It is associated with faster progression and a more severe course of disease. A conjunctival provocation test is only rarely necessary in the diagnosis of allergic conjunctivitis. Treatment of atopic dermatitis with dupilumab, an interleukin 4 receptor alpha (IL-4Ra) antagonist, can cause ocular side effects. Unfortunately, information available on the internet for patients and parents on the topic of VKC is sometimes dangerously incorrect.

CONCLUSION

From the abovementioned new pathogenetic concepts, preventive and personalized treatment options could be developed in the future. Keratoconus in AKC/VKC must be recognized and treated early. Official guidelines are now available for a standardized conjunctival provocation test in the diagnosis of allergic conjunctivitis. The unwanted ocular side effects of dupilumab are often difficult to discriminate from the actual underlying AKC and respond well to anti-inflammatory treatment. Patients with VKC must be informed about the incorrect information on the internet regarding their disease.

Role of the ocular surface microbiome in allergic eye diseases

PURPOSE OF REVIEW

The purpose of this review is to provide an update on emerging literature on the role of the ocular surface microbiome (OSM) in allergic eye diseases.

RECENT FINDINGS

Findings in the literature suggest that the ocular surface microbiome plays a role in the pathophysiology and course of allergic disease of the ocular surface.

SUMMARY

Knowledge regarding the role of the ocular surface microbiome in allergic disease is important to guide development of targets for future therapeutic interventions.