Seasonal and perennial allergic conjunctivitis: the possible role of nasal allergy

Allergic Rhinitis

Allergic rhinitis (AR) affects more than 400 million people worldwide, making it 1 of the most prevalent chronic diseases. Childhood AR is increasing, and almost half of patients with AR develop symptoms before age 6 years. Although a diagnosis of AR is associated with higher socioeconomic status, underserved and urban populations have more indoor aeroallergen sensitizations and are likely underdiagnosed with AR, further exacerbating health-care disparities. AR negatively impacts quality of life, school performance, and overall health outcomes. Untreated AR in children increases the risk for poor asthma control, increased asthma severity, and exacerbations. Many patients believe that they have seasonal allergies only but in reality have both perennial and seasonal AR, which may change the approach to allergen avoidance measures and treatment recommendations. Pharmacotherapy of AR has expanded, with many intranasal corticosteroids, intranasal antihistamines, and second-generation oral antihistamines approved for pediatric use. Allergen immunotherapy, including both subcutaneous and sublingual forms, are approved for children and are disease modifying, potentially reducing further allergen sensitization and progression to asthma. Many of the currently available biological therapies indicated for pediatric asthma and/or atopic diseases reduce AR symptoms as well. Children with moderate to severe or refractory AR or those with comorbidities should be referred to allergists for diagnostic testing and expanded management options, including immunotherapy and potential biological treatment.

Individual multidisciplinary clinical phenotypes of nasal and ocular symptoms in hay fever: Crowdsourced cross-sectional study using AllerSearch

BACKGROUND

Multidisciplinary efforts to prospectively collect and analyze symptoms of hay fever are limited. We aimed to identify the characteristics of nasal and ocular symptoms of hay fever, using the AllerSearch smartphone application.

METHODS

This mobile health-based prospective observational study using the AllerSearch smartphone application was conducted between February 1, 2018, and May 1, 2020. Individuals who downloaded AllerSearch from Japan and provided comprehensive self-assessments (including 17 items related to quality of life [QoL]-related items) were included. The characteristics and risk factors for allergic rhinitis (AR) and allergic conjunctivitis (AC) were identified using hierarchical heat maps and multivariate logistic regression.

RESULTS

Of the 9041 participants with hay fever, 58.8% had AR and AC, 22.2% had AR, and 5.7% had AC. The AR-AC comorbid cohort showed worse symptoms of hay fever and QoL scores than the other cohorts. Factors (odds ratio, 95% confidence interval) associated with AR-AC included a lower age (0.98, 0.97-0.98), female sex (1.31, 1.19-1.45), liver disease (1.58, 1.26-2.35), dry eye disease (1.45, 1.30-1.63), unknown dry eye disease status (1.46, 1.31-1.62), contact lens use discontinuation during the hay fever season (1.69, 1.28-2.23), and bedroom flooring material other than hardwood, carpet, tatami, or vinyl (1.91, 1.16-3.14).

CONCLUSIONS

Analysis of medical big data for hay fever performed using a mobile health app helped identify risk factors and characteristics of AC, AR, and AR-AC. Phenotyping of highly variable symptoms of hay fever, such as nasal and ocular symptoms, can facilitate better-quality clinical care.

Efficacy of olopatadine hydrochloride 0.1%, emedastine difumarate 0.05%, and loteprednol etabonate 0.5% for Chinese children with seasonal allergic conjunctivitis: a randomized vehicle-controlled study

Background

Allergic conjunctivitis (AC) is a disease of various agents that affects the physical and mental health of children. Although the most effective therapy has not been found so far, it is essential to explore the considerable therapeutic method. We compared the clinical efficacy of olopatadine, emedastine, loteprednol etabonate (LE), and vehicle for treating seasonal allergic conjunctivitis (SAC) in Chinese children.

Methods

Eighty cases of 160 eyes aged from 5 to 10 years with SAC were available and those subjects were randomly distributed into 4 groups. Both their eyes received olopatadine hydrochloride 0.1% twice a day, emedastine difumarate 0.05% twice a day, or LE 0.5% 4 times a day, respectively, whereas those of the control group received artificial tears (AT) 0.5% 3 times a day. This study was conducted successfully and the observations were collected before treatment and on day 8 (±1 day) and day 15 (±2 days) afterward. The principal measurement of efficacy was focused on the signs and symptoms of the subjects, evaluated before and after treatment, in addition to visual acuity (VA) and fundus oculi.

Results

On day 8 (±1 day) and day 15 (±2 days), all the antiallergic agents were found to be more effective than vehicle (p < 0.05) in terms of all the symptoms and signs. However, there was no statistical significance (p ≥ 0.05) shown among the treatment groups. There were no evident changes in VA and no clinically significant changes were observed in fundus oculi.

Conclusion

After the treatment, the efficacy presented a similar distribution among the trial groups.

Cytokines in tears during the secondary keratoconjunctival responses induced by allergic reaction in the nasal mucosa

BACKGROUND

Allergic keratoconjunctivitis (KC) can occur in a primary form due to an allergic reaction taking place in the conjunctivae or in a secondary form induced by nasal allergy.

OBJECTIVES

To search for the cytokine changes in tears accompanying the secondary keratoconjunctival response types (SKCR), caused by the nasal allergy.

METHODS

In 43 KC patients developing 15 immediate (SIKCR), 16 late (SLKCR) and 12 delayed (SDYKCR) responses to nasal provocation tests with allergens (NPT), the NPTs were repeated with subsequent recording of cytokine concentrations in tears up to 72 h.

RESULTS

The SIKCRs (p<0.001), occurring 10-120 min after the NPT, were accompanied by significant changes (p<0.05) of interleukin (IL)-4, IL-6, IL-10, IL-12p70 and granulocyte-macrophage colony-stimulating factor (GM-CSF). The SLKCRs (p<0.01), appearing 5-12 h after the NPT, were associated with significant changes (p<0.05) of IL-3, IL-4, IL-5, IL-8, IL-10, tumor necrosis factor (TNF)-α, GM-CSF and granulocyte colony-stimulating factor. The SDYKCRs (p<0.01), occurring 24-48 h after the NPT, were accompanied by significant changes (p<0.05) of IL-2, IL-8, IL-10, interferon-γ, transforming growth factor-β and TNF-α.

CONCLUSIONS

The particular SKCR types, induced by an allergic reaction in the nasal mucosa, were accompanied by different cytokine profiles in the tears, suggesting involvement of different hypersensitivity mechanisms. These results also stress the diagnostic usefulness of NPTs combined with monitoring of ocular features in KC patients who did not respond satisfactorily to the topical ophthalmological treatment.

Cellular changes in tears associated with keratoconjunctival responses induced by nasal allergy

BACKGROUND

Allergic keratoconjunctivitis occurs in a primary form, caused by an allergic reaction localized in the conjunctiva, and in a secondary form, induced by an allergic reaction originating in the nasal mucosa. Various hypersensitivity mechanisms involved in the keratoconjunctivitis forms result in different keratoconjunctival response types.

PURPOSE

To investigate the cytologic changes in tears during the secondary immediate (SIKCR), late (SLKCR), and delayed (SDYKCR) keratoconjunctival responses.

METHODS

In 61 patients, comprising 20 SIKCRs, 23 SLKCRs, and 18 SDYKCRs, nasal provocation tests (NPTs) with allergens and 61 phosphate-buffered control challenges were repeated and supplemented with cell counting in the tears.

RESULTS

The SIKCR (P<0.01), appearing 10-120 min after the NPT, was associated with increased eosinophil and mast cell counts in tears. The SLKCR (P<0.01), appearing 5-12 h after the NPT, was accompanied by increased counts of eosinophils, neutrophils, basophils, and conjunctival epithelial and goblet cells. The SDYKCR (P<0.05), appearing 24-48 h after NPT, was associated with increased counts of lymphocytes, neutrophils, monocytes, basophils, conjunctival epithelial, corneal epithelial and goblet cells.

CONCLUSIONS

The SIKCR, SLKCR, and SDYKCR, induced by nasal allergy, were associated with different cellular profiles in the tears. The cells, except mast, epithelial and goblet cells, displaying no intracellular changes, migrated probably from the conjunctival capillaries, in response to the factors released during the primary allergic reaction in the nasal mucosa and subsequently penetrating into the conjunctiva. These results demonstrate a causal role of nasal allergy and diagnostic value of NPT combined with recording of ocular features and cellular profiles in tears in some keratoconjunctivitis patients.

The anatomical and functional relationship between allergic conjunctivitis and allergic rhinitis

There are numerous anatomic connections between the allergic conjunctivitis and allergic rhinitis. The most obvious reason is the physical connection via the nasolacrimal apparatus. However, a closer look at innervation, circulatory, lymphatic, and neurogenic systems reveals much more than a physical connection. The eye is richly innervated by parasympathetic nerves that enter the eyes after traveling in conjunction with the parasympathetic input to the nasal cavity. Parasympathetic innervation governing the tear film and nasal secretion can intersect at the pterygopalatine ganglion. Neurogenic inflammation affects both the eye and the nose as evidenced by the presence of the same neurogenic factors. Venous flow is in the SOV area connecting the eye and the nose, once thought to be without valves. In the past, this thinking is the basis for concern about the danger triangle of the face. Recent literature has shown otherwise. Although valves are present, there are still pathways where bidirectional flow exists and a venous connection is made. The most likely area for venous communication is the pterygoid plexus and cavernous sinus. The venous flow and connections also offers a pathway for allergic shiners. Understanding the mutual connections between the nasal mucosa and the ocular surface can also affect treatment strategies.

Cytokine profiles in tears accompanying the secondary conjunctival responses induced by nasal allergy

PURPOSE/AIM

Allergic conjunctivitis (AC) occurs either in a primary form, due to the allergic reaction localized in the conjunctivae or in a secondary form, induced by an allergic reaction initiated primarily in the nasal mucosa. The purpose of this study was to investigate the cytokine profiles in tears associated with the secondary conjunctival response (SCR) types.

MATERIALS AND METHODS

In 47 AC patients developing 16 immediate (SICR; p < 0.01), 20 late (SLCR; p < 0.001) and 11 delayed (SDYCR; p < 0.05) responses to nasal provocation tests (NPTs) with allergens, the NPTs were repeated and combined with recording of cytokine concentrations in the tears.

RESULTS

The SCRs were associated with significant concentration changes of particular cytokines in tears (p < 0.05) as follows: (1): SICRs: interleukin (IL)-3, IL-4, IL-10 and granulocyte macrophage colony-stimulating factor (GM-CSF); (2) SLCRs: IL-3, IL-4, IL-5, IL-8, IL-10, IL-12p40, GM-CSF and granulocyte colony-stimulating factor (G-CSF); and (3) SDYCRs: IL-2, IL-8, IL-10, interferon gamma, G-CSF and tumor necrosis factor alpha. No significant cytokine changes were recorded in tears during the phosphate-buffered saline controls or negative SCRs.

CONCLUSIONS

Different cytokine profiles in the tears accompanying the immediate, late and delayed types of SCR, induced by nasal allergy, would indicate involvement of different hypersensitivity mechanisms in the particular SCR types. The low cytokine concentrations in tears recorded during the SCRs may suggest their origin from the nasal mucosa. These results emphasize the diagnostic value of NPTs with allergens combined with monitoring of various ocular features in patients suffering from the secondary form of AC. These results may also have an impact on the therapeutical approach to this clinical entity.

Cytological Changes in Nasal Secretions Accompanying Delayed Nasal Response to Allergen Challenge

Background

Patients with allergic rhinitis when challenged with allergen develop various types of nasal response, such as an immediate nasal response (INR), late nasal response (LNR), dual late nasal response (DLNR), or delayed nasal response (DYNR), probably because of different hypersensitivity mechanisms. This study was designed to investigate the cytological changes in the nasal secretions (NSs) during the DYNR, beginning 24–32 hours, reaching maximum at 32–36 hours, and resolving within 56 hours after the nasal provocation tests (NPTs) with allergens.

Methods

In 45 allergic rhinitis patients developing 45 positive DYNRs (p < 0.01), the NPTs and the phosphate-buffered saline (PBS) controls were repeated and supplemented with cytological examination of the NSs and determination of interferon (IFN) γ and IL-4 in nasal lavage fluid (NLF).

Results

The repeated DYNR (p < 0.001) was accompanied by significant changes (p < 0.05) in the counts of neutrophils, monocytes, lymphocytes, epithelial and goblet cells, and, to a limited extent, of plasma cells and platelets in the NSs and increased concentrations of IFN-γ but not of IL-4, in NLF between 24 and 48 hours after the NPT. No significant cytological changes were found in NSs during the PBS controls (p > 0.1).

Conclusion

The DYNR is associated with cytological profiles in the NS different from those observed during the INR or LNR. The significant count changes of neutrophils, monocytes, lymphocytes, epithelial and goblet cells in NSs, and increased IFN-γ but not of IL-4 concentrations in the NLF, suggest a possible involvement of the cell-mediated hypersensitivity in the DYNR. These results also emphasize the diagnostic value of NPTs combined with cytological examination of the NSs in patients with nasal allergy.

Allergic conjunctivitis and nasal allergy

Allergic conjunctivitis (AC) can be divided into the primary form (caused by an allergic reaction occurring primarily in the conjunctivae) and the secondary form (induced by allergic reaction originating primarily in the nasal mucosa, where the released mediators can reach conjunctiva through the lacrimal system, the blood, the lymphatic network, or the neurogenic network). Patients with primary AC develop an immediate, late, or delayed conjunctival response (CR) during conjunctival provocation tests. Patients with secondary AC develop an immediate, late, or delayed type of secondary CR, induced by the nasal allergic reaction, due to the nasal allergen challenge. Various hypersensitivity mechanisms may be involved in the particular CR types. The secondarily induced AC and CRs can only be confirmed by nasal provocations tests, performed by rhinomanometry combined with recording of conjunctival signs. The existence of the primary and secondarily induced AC has an impact on treatment of this disorder.

Conjunctival effects of a selective nasal pollen provocation

BACKGROUND

Several clinical and experimental observations suggest that allergen deposition in the nose may partially be responsible for the induction of conjunctival symptoms in allergic rhinitis. The aims of this study were to evaluate the induction of conjunctival symptoms by selective nasal allergen provocation and to assess the feasibility of the different tools for evaluation of conjunctival allergic inflammation.

METHODS

Grass pollen allergic subjects with rhinoconjunctivitis symptoms during the pollen season (n = 12) underwent a nasal sham and grass pollen provocation extra-seasonally. Nasal and conjunctival symptoms were scored using the Visual Analogue Scale (VAS) system at baseline, 15 min, 1 h and 24 h after provocation. In addition to Peak Nasal Inspiratory flow (PNIF) measurements, conjunctival inflammation and vascular congestion were evaluated and histamine and substance P levels in tear fluid were measured.

RESULTS

Selective nasal grass pollen provocation induced ocular pruritus, lacrimation and conjunctival vascular congestion. PNIF values correlated inversely with lacrimation (r = -0.71, P < 0.001) and ocular pruritus (r = -0.41, P < 0.05). Four out of 11 patients showed a conjunctival eosinophilic inflammation and levels of histamine (r = 0.73, P < 0.05) and substance P (r = 0.67, P = 0.05) in tear fluid correlated with conjunctival symptoms.

CONCLUSION

Selective nasal grass pollen provocation induced conjunctival inflammation, ocular pruritus and lacrimation, which correlated with histamine and substance P levels in tear fluid and inversely with the PNIF values. These data show a naso-ocular interaction in allergic rhinitis and offer objective tools for evaluation of conjunctival inflammation in allergic rhinoconjunctivitis.

Allergic conjunctivitis and the impact of allergic rhinitis

Although nasal allergy has been prominent in allergy research, ocular allergy is increasingly recognized as a distinct symptom complex that imposes its own disease burden and reduction in patients' quality of life. In the past year, knowledge of the relationships between allergic conjunctivitis and allergic rhinitis has increased. Allergic conjunctivitis is highly prevalent and has a close epidemiologic relationship with allergic rhinitis. Both conditions also exhibit similar pathophysiologic mechanisms. Pathways of communication are thought to increase the likelihood of an inflammatory reaction at both sites following allergen exposure of nasal or ocular tissue. Clinical trials of intranasal therapies have demonstrated efficacy in allergic conjunctivitis and rhinitis. Newer intranasal steroids decrease ocular symptoms, potentially achieving efficacy by suppressing the naso-ocular reflex, downregulation of inflammatory cell expression, or restoration of nasolacrimal duct patency. Proposed pathophysiologic interactions between allergic rhinitis and ocular allergy underscore the need for therapies with efficacy in both symptom sets.