Are Markers of Allergic Inflammation in Grass Pollen Allergy Influenced by H1 Antihistamines?

Soluble intercellular adhesion molecule-1 (ICAM-1) and soluble vascular adhesion molecule-1 (VCAM-1) play important roles in allergic rhinitis (AR). Treatment with H1 antihistamines improves AR symptoms and in vitro reduces the levels of adhesion molecules. The aim of the study was to evaluate serum levels of ICAM-1 and VCAM-1 in patients with AR to grass pollen and their response to different H1 antihistamines. Material and methods: A total of 50 patients with grass pollen AR were clinically and biologically evaluated. ICAM-1 and VCAM-1 serum levels were evaluated during pollen season before and after treatment with levocetirizine and desloratadine through the ELISA method. Results: ICAM-1, VCAM-1, eosinophils, and total IgE were elevated in patients with AR, compared with healthy subjects. Both antihistamines improved specific symptoms of AR and increased patients’ quality of life during pollen season after one month of treatment. H1 antihistamines reduced VCAM-1, ICAM-1, and total IgE after one-month treatment but not significantly. Patients with increased baseline values tend to remain with increased values after one-month AH1 treatment. Conclusions: ICAM-1 and sVCAM-1 levels are higher in patients with grass pollen-induced AR than healthy controls during pollen exposure. Their serum levels tend to remain at high values during pollen season despite antihistaminic therapy.

Rupatadine to prevent local allergic reactions to sublingual allergy immunotherapy: a case series

Background Sublingual immunotherapy tablets (SLIT-T) are an effective treatment for allergic rhinitis (AR), but some patients experience local allergic reactions (LAR) in the first few weeks of treatment that can lead to treatment discontinuation. Although oral antihistamines are recommended for the treatment and pretreatment of LAR associated with SLIT-T, there are no clinical trial data to support this recommendation. Rupatadine is an H1 antihistamine that also inhibits platelet activating factor activity. The objective of this case series is to describe real-world clinical situations in which rupatadine was used to treat or mitigate SLIT-T–related LAR. Case presentations Five cases are presented by the managing allergist and off-label use of rupatadine is their expert opinion only. Patients in all 5 cases were treated with a SLIT-T (e.g. ragweed, tree, grass, or house dust mites) for the management of allergic rhinitis and experienced bothersome LAR with the first SLIT-T administration. In 3 cases, rupatadine 10 mg was administered for the immediate treatment of LAR (either in-office with the first SLIT-T dose or for subsequent LAR experienced at home) and the symptoms resolved. In 3 cases, pretreatment with other second-generation H1 antihistamines was unable to prevent LAR and the patients discontinued the SLIT-T. In these 3 cases, switching to pretreatment with rupatadine allowed the patients to restart and tolerate SLIT-T treatment with minimal or no LAR. In these patients with an established history of LAR, proactive pretreatment with rupatadine in subsequent seasons or with initiation of a different SLIT-T mitigated the previously experienced LARs. Conclusions In the cases presented, treatment with rupatadine resolved LAR associated with SLIT-T treatment and rupatadine pretreatment appeared to mitigate subsequent LAR. Rupatadine may be an option to treat or improve the tolerability of the SLIT-T, potentially improving early treatment persistence.

Omalizumab for the treatment of chronic spontaneous urticaria: a systematic review

<p class="abstract">Chronic spontaneous urticaria (CSU) is a mast cell-driven skin disease characterized by the recurrence of transient wheals, angioedema or both lasting for more than 6 weeks duration. Omalizumab is a newer humanized anti IgE immunoglobulin along with many new antibody treatments has shown beneficial effect in treatment of chronic spontaneous urticaria. Although many randomized clinical trials have been conducted, as of now, the effectiveness of omalizumab in the real world management of CSU is largely unknown. A systematic review of all studies should be done. The objective was to study the efficacy and safety of different doses of omalizumab in the treatment of chronic spontaneous urticaria which was refractory to treatment with H1 antihistamines. Suitable studies were recognized after searching Wiley online library, PubMed, Google scholar, NEJM/NEJ dermatology, JAAD, JACI, clinicaltrials.gov. Only randomized, double-blind, placebo-controlled clinical trials with omalizumab versus antihistamine or leukotriene antagonists as placebo were involved in this study. 10 randomized, placebo-controlled studies were involved with 1692 patients with CSU. Patients treated with omalizumab (75-600 mg every 4 weeks) had reduced UAS7 score, improved QoL (quality of life), reduced WISS, when compared to the placebo group. The effects of omalizumab were found to be dose dependent, with maximum reduction in UAS7 at a dose of 300 mg when given at an interval of 4 weeks’ duration. The incidences of adverse events were almost similar in both control and placebo groups and across various dose ranges. The best effect in reduction of clinical symptoms and QoL in CSU patients was found at a dose of 300 mg subcutaneous injection once a month of omalizumab for 12 to 24 weeks. Omalizumab was found to reduce the clinical symptoms and signs in patients with CSU who were symptomatic despite treatment with upscaling dose of H1 antihistamines.</p>

The Role of Anti-IgE Antibodies in Urticaria

Chronic urticaria, a common mast cell driven disease, has been considered so far an underestimated and difficult to treat disease, very often resulting in high physical, psychological and socio-economic burden. More than 60% of these patients are unresponsive to second generation H1 antihistamines, the first-line symptomatic treatment for urticaria. However, anti-IgE drugs (omalizumab and ligelizumab) showed improved activity in urticaria-treated patients with inadequate symptom control. Omalizumab has been widely proven to be very effective and well-tolerated in patients with antihistamine-refractory chronic spontaneous urticaria and inducible urticaria and is currently licensed for these indication as third-line treatment. Ligelizumab, a next-generation monoclonal anti-IgE antibody with higher affinity to IgE compared to omalizumab and a similar safety profile, has recently demonstrated to be even more effective than omalizumab. This review is focused on the role of anti-IgE antibodies in chronic urticaria.

Histamine Intolerance—The More We Know the Less We Know. A Review

The intake of food may be an initiator of adverse reactions. Food intolerance is an abnormal non-immunological response of the organism to the ingestion of food or its components in a dosage normally tolerated. Despite the fact that food intolerance is spread throughout the world, its diagnosing is still difficult. Histamine intolerance (HIT) is the term for that type of food intolerance which includes a set of undesirable reactions as a result of accumulated or ingested histamine. Manifestations may be caused by various pathophysiological mechanisms or a combination of them. The problem with a “diagnosis” of HIT is precisely the inconstancy and variety of the manifestations in the same individual following similar stimuli. The diagnosing of HIT therefore requires a complex time-demanding multidisciplinary approach, including the systematic elimination of disorders with a similar manifestation of symptoms. Among therapeutic approaches, the gold standard is a low-histamine diet. A good response to such a diet is considered to be confirmation of HIT. Alongside the dietary measures, DAO supplementation supporting the degradation of ingested histamine may be considered as subsidiary treatment for individuals with intestinal DAO deficiency. If antihistamines are indicated, the treatment should be conscious and time-limited, while 2nd or 3rd generation of H1 antihistamines should take precedence.

Management of allergic rhinitis with leukotriene receptor antagonists versus selective H1-antihistamines: a meta-analysis of current evidence

Background Inconsistencies remain regarding the effectiveness and safety of leukotriene receptor antagonists (LTRAs) and selective H1-antihistamines (SAHs) for allergic rhinitis (AR). A meta-analysis of randomized controlled trials (RCTs) was conducted to compare the medications. Methods Relevant head-to-head comparative RCTs were retrieved by searching the PubMed, Embase, and Cochrane’s Library databases from inception to April 20, 2020. A random-effects model was applied to pool the results. Subgroup analyses were performed for seasonal and perennial AR. Results Fourteen RCTs comprising 4458 patients were included. LTRAs were inferior to SAHs in terms of the daytime nasal symptoms score (mean difference [MD]: 0.05, 95% confidence interval [CI] 0.02 to 0.08, p = 0.003, I2 = 89%) and daytime eye symptoms score (MD: 0.05, 95% CI 0.01 to 0.08, p = 0.009, I2 = 89%), but were superior in terms of the nighttime symptoms score (MD: − 0.04, 95% CI − 0.06 to − 0.02, p < 0.001, I2 = 85%). The effects of the two treatments on the composite symptom score (MD: 0.02, 95% CI − 0.02 to 0.05, p = 0.30, I2 = 91%) and rhinoconjunctivitis quality-of-life questionnaire (RQLQ) (MD: 0.01, 95% CI − 0.05 to 0.07, p = 0.71, I2 = 99%) were similar. Incidences of adverse events were comparable (odds ratio [OR]: 0.97, 95% CI 0.75 to 1.25, p = 0.98, I2 = 0%). These results were mainly obtained from studies on seasonal AR. No significant publication bias was detected. Conclusions Although both treatments are safe and effective in improving the quality of life (QoL) in AR patients, LTRAs are more effective in improving nighttime symptoms but less effective in improving daytime nasal symptoms compared to SAHs.

Modern H1- antihistamines in the treatment of allergic rhinitis: focus on bilastine

The second generation of H1-antihistamines is approved for the stepwise treatment of seasonal and perennial allergic rhinitis in adults and children by international and national guidelines. They reduce the severity of nasal and ocular symptoms of rhinitis and improve the quality of life of patients. Bilastine, a piperidine derivative, is a novel H1-antihistamine. It has a potent and selective effect on H1- receptors and a rapid onset and long duration of action and substantially reduces nasal and ocular symptoms of seasonal and perennial allergic rhinitis. Bilastine has no clinically substantial hepatic metabolism and has a high safety profile: it has no sedative effect, does not affect cognitive functions, has no cardiotoxic effects, and does not interact with alcohol and benzodiazepines in normal and high doses. Tachyphylaxis does not develop despite long-term (up to 1 year) use. Bilastine is registered for clinical use in adults and children aged 12 years. The results of clinical and experimental studies have demonstrated that bilastine has many of the features of modern H1-antihistamines recommended by international guidelines.

Anti-inflammatory activity of the antiallergic drug 7-[4-(4-benzhydrylpiperazinyl-1)butyl]-3-methylxanthine succinate (theoritin)

BACKGROUND: Many antagonists of histamine (H1) receptor, in addition to antihistamine action, suppress allergic inflammation by inhibiting the formation and secretion of proinflammatory cytokines. The new antiallergic drug benzhydrylpiperazinyl butylmethylxanthine succinate (theoritin), which has an antihistamine activity comparable to the known second generation H1-antihistamines, surpasses them in the ability to suppress the allergic inflammatory reaction, which allows this drug to have additional anti-inflammatory properties associated with the inhibition of the formation of proinflammatory cytokines. AIM: This study aimed to determine the effect of theoritin on the induced release of proinflammatory cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)- in cell culture in comparison with the action of the inverse agonist of H1 receptor cetirizine and a known inflammation inhibitor glucocorticosteroid dexamethasone. MATERIALS AND METHODS: U937 cells differentiated toward macrophage-like cells were used. Cytotoxicity of the substances used was assessed in the methyltetrazolium test at different incubation times (up to 24 h). Cells were stimulated with lipopolysaccharide (LPS). The tested compounds (theoritin and cetirizine) were evaluated at concentrations from 0.001 to 100 M and dexamethasone at 10 M was tested when added to cells 1 h before (prophylactic effect) or 1 h after (therapeutic effect) the addition of LPS. The presence of IL-6, IL-8, and TNF in the supernatants was determined by enzyme immunoassay. RESULTS: For cetirizine and theoritin, no cytotoxic action was found in the tested concentrations and time points. Dexamethasone inhibited the formation of IL-6 and TNF to the initial level and IL-8 to 50%60%. Theoritin led to a significant concentration-dependent decrease in the LPS-induced production of IL-6, IL-8, and TNF, and at a concentration of 100 M, the effect of theoritin was comparable with that of dexamethasone at a concentration of 10 M. The prophylactic test scheme for theoritin was more effective in suppressing LPS-induced production of proinflammatory cytokines than the curative one. The described effect of theoritin on LPS-induced production of proinflammatory cytokines exceeded that of the reference drug cetirizine. CONCLUSION: In addition to its antihistaminic action, theoritin, a new antiallergic agent, inhibits LPS-induced production of proinflammatory cytokines, which may be of clinical importance in suppressing allergic inflammation.

Cholinergic urticaria: novel aspects of pathogenesis, diagnosis and management

Cholinergic urticaria (CholU) is a chronic inducible urticaria, characterised by itchy pinpoint wheals up to 3 mm in diameter, surrounded by a prominent flare, that occur following an exposure to characteristic triggers such as active or passive heating, physical exercise, emotions, hot or spicy foods. Key pathophysiologic mechanisms include immediate hypersensitivity to autologous sweat antigens, functional sweating disorders, impaired acethylcholine metabolism, abnormal skin vascular permeability and disturbed skin innervation. Clinical manifestations of CholU may vary from typical itchy pinpoint urticarial lesions, angioedema to anaphylaxis. Atypical CholU forms include cholinergic pruritus, cholinergic dermographism, cold cholinergic urticaria and persistent cholinergic erythema. The diagnosis of cholinergic urticaria relies on patients history, сlinical manifestations and challenge tests. Treatment options include nonsedating H1 antihistamines in standard or increased doses. The evidence is accumulating for the use of biological treatment with omalizumab in cholinergic urticaria. The prospect of personalized treatment of cholinergic urticaria include autologous sweat desensitization. The main research efforts in ColdU are directed at optimizing diagnostic approaches and developing innovative therapeutic options.