
Hypersensitivity reactions (HRs) to contrast media (CM) can be distinguished in immune-mediated (including allergic reactions) and non-immune-mediated reactions, even if clinical manifestations could be similar. Such manifestations range from mild skin eruptions to severe anaphylaxis, making it important for radiologists to know how to identify and manage them. A panel of experts from the Società Italiana di Radiologia Medica e Interventistica (SIRM) and the Società Italiana di Allergologia, Asma e Immunologia Clinica (SIAAIC) provided a consensus document on the management of patients who must undergo radiological investigations with CM. Consensus topics included: the risk stratification of patients, the identification of the culprit CM and of a safe alternative by an allergy workup, as well as the use of premedication and the correct procedure to safely perform an elective (i.e., scheduled) or urgent examination. The most important recommendations are: (1) in all patients, a thorough medical history must be taken by the prescribing physician and/or the radiologist to identify at-risk patients; (2) in patients with hypersensitivity reactions to CM, the radiologist must consider an alternative, non-contrast imaging study with a comparable diagnostic value, or prescribe a different investigation with another class of CM; (3) if such options are not feasible, the radiologist must address at-risk patients to a reference centre for an allergy evaluation; (4) if timely referral to an allergist is not viable, it is recommended to use a CM other than the responsible one, taking into account cross-reactivity patterns; in the case of patients with histories of severe reactions, the presence of an anesthesiologist is also recommended and a premedication is suggested.
Asthma is a chronic condition that affects children worldwide. Accumulating number of studies reported that the prevalence of pediatric obesity and asthma might be altered through breastfeeding. It has been proposed that Leptin, which exists in human milk, is oppositely associated with weight increase in newborns. It may also influence peripheral immune system by promoting TH1 responses and suppressing TH2 cytokines. Leptin influences body weight and immune responses through complex signaling pathways at molecular level. Although previous studies provide explanations for the protective role of breastfeeding against both obesity and asthma, other factors such as duration of breastfeeding, parental, and prenatal factors may confound this relationship which requires further research.
Background Primary Systemic Sclerosis (PSS) is a connective tissue disorder characterized by excessive collagen deposition in the skin and internal organs. Interstitial lung disease (ILD) is a late demonstration of PSS and cytokines can contribute to the disease pathology. The purpose of the current study was to determine the association between serum interleukin-6 level and pulmonary involvement in progressive systemic sclerosis. Methods and materials Demographic data and serum interleukin-6 levels were measured for 30 PSS patients with pulmonary involvement (case group) and 30 PSS patients without pulmonary involvement (control group) following informed consent. The disease duration and activity, C-reactive protein (CRP), chest x-ray and highresolution CT scan (HRCT) findings, ejection fraction (EF) and echocardiography findings, and pulmonary artery pressure (PAP) were also determined in both groups. Results The age of patients in case and control groups was 52.5 ± 9.3 and 43.9 ± 9.7 years, respectively (p = 0.001). No significant difference was found between serum levels of IL-6 in case and control groups (73.1 ± 95.4 vs 46.7 ± 83.6 pg/ml, p = 0.267). However, IL-6 level was significantly higher in male case patients compared to male controls (p = 0.007). The duration of PSS was 11.6 ± 6.4 and 7.4 ± 4.2 years in case and control groups, respectively (p = 0.002). The quantitative CRP and PAP was also significantly higher in case patients (p = 0.01 and p < 0.001, respectively). There was found reticulonodular pattern in 20 (66.7%) of the cases, whereas 28 (93.3%) of the controls had normal Chest X-rays (CXR) (p < 0.001). EF was significantly lower in case patients compared to control patients (p = 0.001). Conclusion The serum level of IL-6 did not appear to have a relationship with pulmonary involvement, hence it could not be regarded as a potential therapeutic target.
It is clinically important to identify allergens in Artocarpus heterophyllus (jackfruit), Moringa oleifera (moringa), Trianthema portulacastrum (horse purslane) and Syzygium samarangense (rose apple). This study included 7 patients who developed anaphylaxis to jackfruit (1), moringa (2), horse purslane (3) and rose apple (1). We sought to determine allergens in the edible ripening stages of jackfruit (tender, mature, and ripened jackfruit) and seeds, edible parts of moringa (seeds, seedpod, flesh inside seedpod, and leaves), horse purslane leaves and ripened rose apple fruit. The persistence of the allergens after cooking was also investigated. Allergens were identified by clinical history followed by a skin prick test. Protein profiles of plant/fruit crude protein extracts were determined by SDS-PAGE. Molecular weights of the allergens were determined by immunoblotting with patient sera. A heat-stable allergen of 114 kDa in A. heterophyllus which is shared among different ripening stages and seeds was identified. Additionally, 101 kDa allergen in boiled tender jackfruit, 86 kDa allergen in boiled seeds and 80 kDa allergen in boiled mature jackfruit were identified. Five heat-stable allergens of 14, 23, 35, 43, and 48 kDa in M. oleifera, 1 heat-stable allergen of 97 kDa in T. portulacastrum, and 4 allergens of 26, 31. 60, and 82 kDa in S. samarangense were identified. Novel IgE-sensitive proteins of A. heterophyllus, M. oleifera, T. portulacastrum and S. samarangense were identified which would be especially useful in the diagnosis of food allergies. The identified allergens can be used in Component Resolved Diagnostics (CRD).
Abstract Background Maternal probiotic supplementation has a promising effect on atopic dermatitis (AD) prevention in infancy. In the randomised controlled study, Probiotics in the Prevention of Allergy among Children in Trondheim (ProPACT), maternal probiotics reduced the cumulative incidence of AD in their offspring by 40% at 2 years of age. However, our understanding on how probiotics prevented AD is still limited, and the role of inflammatory proteins in infants following maternal probiotic supplementation is unclear. We hypothesised that maternal probiotics lowered pro-inflammatory proteins and increased anti-inflammatory proteins in their 2-year-old children as a mechanism of AD prevention. We aimed to explore this hypothesis and the association between these proteins and the presence of AD, severity of AD, and the degree of preventive effect of probiotics. Methods Plasma samples were collected from 2-year-old children (n = 202) during the ProPACT study, a randomised placebo-controlled trial of maternal probiotic supplementation. These samples were analysed for 92 inflammatory proteins using a multiplex proximity extension assay. Associations between inflammatory proteins and the presence and severity of AD, and the degree of preventive effect, was estimated individually using regression analysis and then collectively using unsupervised cluster analysis. Results Several proteins were observed to differ between the groups. The probiotic group had lower CCL11 and IL-17C, while children with AD had higher IL-17C, MCP-4, uPA, and CD6. Cytokine CCL20 and IL-18 had moderate correlation (r = 0.35 and r = 0.46) with the severity of AD. The cluster analysis revealed that children in the cluster of samples with the highest value of immune checkpoint receptors and inflammatory suppressor enzymes showed the greatest AD preventive effect from probiotics. Conclusions The proteins associated with both maternal probiotic supplementation and the presence and severity of AD warrant attention because of their potential biological relevance. Cluster analysis may provide a new insight when considering which subgroups benefit from probiotic supplementation. Larger studies are needed to confirm the results. Trial registration number: The study was retrospectively registered at ClinicalTrials.gov (NCT00159523) on 12nd September 2005.
Background Non-specific lipid-transfer protein (nsLTP) is a pan-allergen in the plant world, and a cause of significant concern as food allergen in the Mediterranean area, due to its general heat- and acid-resistance and hence the risk of severe allergic reactions. Pru p 3 , the peach nsLTP, is considered the primary sensitizer to this allergen family and this allergy is usually persistent. Allergen-free diet and acute treatment of manifestations are the main recognized management goals in food allergy. Main text The role of immunotherapy for treating food allergy in adult patients is controversial, but immunotherapy for Pru p 3 could potentially represent a relevant therapeutic strategy. We systematically searched databases for studies assessing the role of immunotherapy Pru p 3 in food allergy. Overall, nine studies were included. Immunotherapy with Pru p 3 appears to be effective and with a good safety profile in both peach and LTP allergy for some foods, such as peanut, in both RCT and real-life studies. Conclusions Immunotherapy with Pru p 3 is a possible treatment option for food allergy to the peach LTP in the Mediterranean area, although at present have not reached routinary clinical practice. Larger studies are needed to confirm these findings and identify predictive biomarkers.
Background Asthma is the most prevalent respiratory disease caused by chronic airway inflammation. Attention Deficit Hyperactivity Disorder (ADHD) is children's most common psychological and neurodevelopmental disorder. Increased risk for ADHD in patients with inflammatory and autoimmune diseases supports the role of inflammatory mechanisms in the occurrence of ADHD. However, the association between asthma and ADHD remains unclear. Objective This study was designed to evaluate the prevalence of ADHD in patients with asthma who were referred to the clinic of allergy and clinical immunology. Methods This cross-sectional study was conducted on children aged 6 to 18 with asthma at Imam Ali hospital, Karaj, Iran. The patient's demographic data, history of childbirth delivery type, premature birth, hospital admission, family income, birth rate, and family history information related to the patient's asthma and medicines were recorded. ADHD diagnosis was made using the Persian version of Conners Parent Behavioral Problems Rating Scale (CPRS-26). Results In this study, 677 asthmatic patients were enrolled; 46 patients (6.8%) had ADHD. The probability of ADHD in asthmatic patients inhabited in a rural area, males, and patients with a history of food allergy, allergic rhinitis, urticaria, and eczema was significantly higher (p < 0.05). In addition, our result demonstrated that the likelihood of ADHD in patients with asthma and a history of PICU admission was significantly higher (p < 0.05). Conclusions The present study showed that severe asthma, was the risk factor for ADHD in patients with asthma. Physicians should be aware of this co-morbidity to refer asthmatic patients who have the symptoms of ADHD to a psychologist.
Background The accuracy of an atopy patch test (APT) for fresh cow’s milk allergy is controversial. Few studies have focused on commercial extract solutions. We aimed to evaluate the diagnostic performance of the APT in cow’s milk allergic children using fresh cow’s milk and commercial extracts of cow’s milk and its components including casein, α-lactalbumin, and β-lactoglobulin. Methods A prospective study was carried out in children with a history of cow’s milk allergy. Children underwent the skin prick test (SPT) and APT with fresh cow’s milk, powdered cow’s milk, and commercial extracts of cow’s milk, casein, α-lactalbumin, and β-lactoglobulin. Oral food challenge (OFC) was confirmed in all children. Results A total of 37 patients participated (mean age 13.14 ± 7.26 months). Only 5 (13.51%) patients had positive OFC to cow’s milk. The sensitivity of the APT using fresh cow’s milk was 40%, specificity was 65.6%, PPV was 15.4%, and NPV was 87.5%. The sensitivity of the APT using powdered cow’s milk was 40%, 60.7% for specificity, 15.4% for PPV, and 58% for NPV. The sensitivity and PPV of the APT using commercial solutions of cow’s milk, casein, α-lactalbumin, and β-lactoglobulin were zero. The specificities were 90.6%, 93.8%, 100%, and 100% for α-lactalbumin, cow’s milk, casein, and β-lactoglobulin, respectively. Conclusions APT using commercial solutions showed higher specificity than fresh milk. The specificity increased using a protein component allergen.
Background As the process and nature of developing sensitivity to house dust mites (HDMs) remain not fully studied, our goal was to establish the pattern, nature and timeframe of house dust mite (HDM) sensitization development in patients in Ukraine as well as the period when treatment of such patients would be most effective. Methods The data of the multiplex allergy test Alex 2 was collected from 20,033 patients. To determine age specifics of sensitization, descriptive statistics were used. Bayesian Network analysis was used to build probabilistic patterns of individual sensitization. Results Patients from Ukraine were most often sensitized to HDM allergens of group 1 (Der p 1, Der f 1) and group 2 (Der p 2, Der f 2) as well as to Der p 23 (55%). A considerable sensitivity to Der p 5, Der p 7 and Der p 21 allergens was also observed. The overall nature of sensitization to HDM allergens among the population of Ukraine is formed within the first year of life. By this time, there is a pronounced sensitization to HDM allergens of groups 1 and 2 as well as to Der p 23. Significance of sensitization to Der p 5, Der p 7 and Der p 21 allergens grows starting from the age of 3–6. Bayesian Network data analysis indicated the leading role of sensitization to Der p 1 and Der f 2. While developing the sensitivity to group 5 allergens, the leading role may belong to Der p 21 allergen. Conclusion The results obtained indicate the importance of determining the sensitization profile using the multi-component approach. A more detailed study of the optimal age for AIT prescription is required as the pattern of sensitization to HDMs is formed during the first year of life.
Systemic drug-related intertriginous and flexural exanthema (SDRIFE) is an adverse drug reaction which manifests as a symmetrical erythematous rash involving the skin folds after systemic drug exposure. A vast array of possible side effects associated with administration of different anti-SARS-CoV-2 vaccines have been reported in literature since the beginning of the COVID-19 pandemic, but only few times SDRIFE-like eruptions have been described in this context. We discuss here a case of SDRIFE-like eruption following the second dose of Oxford-Astrazeneca Vaxzevria vaccine.
Background Biologics are currently one of the main treatment options for a number of diseases. The IgG4 monoclonal antibody dupilumab targets the Interleukin-4 receptor alpha chain, thus preventing the biological effects of the cytokines IL-4 and IL-13, that are essential for the Th2 response. Several controlled trials showed that dupilumab is effective and safe in patients with atopic dermatitis (AD), severe asthma and chronic rhinosinusitis with nasal polyps (CRSwNP), thus resulting in approval by regulatory agencies. Aim of the study was to evaluate the efficacy and safety of dupilumab in adult patients with CRSwNP stratified by common overlapping comorbid conditions. Methods We performed a multicenter, observational, prospective study enrolling adult patients with severe CRSwNP who had started dupilumab treatment in the context of standard care from January 2021 to October 2021. Data were collected from twentynine Italian secondary care centers for allergy and clinical immunology, all of which were part of the Italian Society of Allergy, Asthma and Clinical Immunology (SIAAIC). A number of efficacy parameters were used. Patient data were compared using the Wilcoxon test for paired data. All statistical analyses were performed with SPSS version 20 (IBM, Armonk, NY, USA). Results In total, 82 patients with nasal polyposis were identified. A significant improvement was detected for all the applied efficacy parameters, i.e. 22-item Sino-Nasal Outcome Test (SNOT-22) and bilateral endoscopic nasal polyp score (NPS) scores for CRSwNP, Rhinitis Control Scoring System (RCSS) and Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) scores for allergic perennial rhinitis, Forced Expiratory Volume in the 1st second (FEV1) and Asthma Quality of Life Questionnaire (AQLQ) scores for asthma, Eczema Area and Severity Index (EASI) and Dermatology Life Quality Index (DLQI) scores for AD. A non-significant improvement was also obtained in the Urticaria Activity Score over 7 days (UAS7) for chronic spontaneous urticaria. Treatment with dupilumab was well tolerated. Conclusions These data suggest that dupilumab treatment in patients suffering from CRSwNP and associated comorbidities may be suitable. Such outcome, although confirmation by trials is warranted, suggests the possibility to treat different disorders with a single therapy, with favorable effects especially under the cost-effectiveness aspect.
Despite the low prevalence of IgE sensitivity to fresh or boiled coconut milk and coconut oil, those may contain allergens of which the clinical significance remains undetermined. This study aimed to identify and compare allergens in fresh coconut milk (FCM), boiled coconut milk (BCM), unrefined wet-processed coconut oil (WPCO), and dry-processed coconut oil (DPCO) using sera from patients with allergy to coconut milk. The study included 18 patients with immediate hypersensitivity to coconut milk, including five who developed anaphylaxis. Sensitization was assessed by skin prick test and ImmunoCAPs using commercially available coconut extracts. Immunoblotting was performed to identify and compare allergen profiles. Total sIgE levels and overall IgE reactivity of patients with anaphylaxis were higher compared to patients with allergy. Twelve allergens ranging from 5 to 128 kDa including six novel allergens with 5, 12, 47, 87, 110, and 128 kDa were visualized in immunoblots with FCM. Similarly, nine allergens of 5, 12, 17, 32, 35, 47, 87, 110, and 128 kDa were detected in BCM. One allergen (110 kDa) was discerned in all four extracts. Higher IgE prevalence was detected with three allergens of 55, 87, and 110 kDa. Allergens of BCM and unrefined coconut oil (WPCO and DPCO) were determined for the first time. Novel allergens of 87 and 110 kDa and the 55 kDa allergen have the highest potential to be used in Component Resolved Diagnostics. Further, these findings demonstrate that, patients who have an allergy to coconut milk could also react to boiled coconut milk and unrefined coconut oil.
Abstract Objectives This study aimed to determine the levels of IgM and IgG antibody response to the severe acute respiratory syndrome coronavirus (SARS-CoV)-2 in coronavirus disease 2019 (COVID-19) patients with different disease severity. Methods IgM and IgG antibody levels were evaluated via enzyme-linked immunosorbent assay (ELISA). In total, 100 patients with confirmed SARS-CoV-2 infection were enrolled in this study and viral RNA was detected by using Real-time PCR technique. Clinical and laboratory data were collected and analyzed after hospital admission for COVID-19 and two months post-admission. Results The level of anti-SARS-CoV-2 antibody IgG was significantly higher in the severe patients than those in moderate and mild groups, 2 months after admission. Also, level of IgG was positively associated with increased WBC, NUT and LYM counts in sever than mild or moderate groups after admission to hospital. Conclusion Our findings suggested that patients with severe illness might experience longer virus exposure times and have a stronger antibody response against viral infection. Thus, they have longer time immunity compared with other groups.
Abstract Background Food allergy is becoming increasingly common among the pediatric population. Despite strict avoidance of food allergens, a subgroup of sensitive individuals still develops frequent, persistent, and difficult to treat hives (FPDTH) for which there is no curative therapy. Although these cases are rare, these patients are in most need of therapy. Case presentations This is a retrospective review of 3 pediatric patients with highly sensitive food allergies who initially presented with hives daily or every other day, or multiple times a day, but achieved marked remission after traditional Chinese medicine (TCM) therapies. Patient 1 (P1) is a 5-year-old who has experienced 140 reactions in his lifetime. Reactions were mostly hives with 4 episodes of anaphylaxis. P1 had used Prednisone 20 times, had an Epinephrine injection 4 times, and had 3 emergency room (ER) visits. Patient 2 (P2) is a 12-year-old who had experienced hives since age 3. Despite daily antihistamine use, P2 had > 730 reactions in his lifetime at the time of presentation including 2 episodes of anaphylaxis. He had been prescribed prednisone 4 times, an Epinephrine injection 2 times, and had 1 ER visit. Patient 3 (P3) is a 20-month-old girl who had experienced > 120 reactions including 1 episode of anaphylaxis. She was on daily desonide and frequently used an antihistamine, yet still had required a course of prednisone once, an Epinephrine injection once, and had 1 ER visit to manage her reaction. After presenting to our clinic, patients received internal and external TCM treatments, including herbal baths and creams (Remedy A-D) as basic remedies to reduce food reactions, including but not limited to frequent hives. Within 7–9 months of TCM treatment, remarkably all patients had complete remission of atopic symptoms. All three patients also experienced an improvement in other conditions including food intolerance, diarrhea, anxiety, eczema, and environmental allergies. After 1 year of treatment, all three patients had reductions in food-specific IgE levels that had been previously elevated, and additionally, P1 and P3, who initially had high total IgE levels, experienced a marked decrease in total IgE levels as well. All three patients continued to introduce foods into their diet that they previously had reactions to, and all 3 patients remain symptom-free. Conclusions Three pediatric patients with a known history of multiple food sensitivities and physician-diagnosed food allergies that presented with FPDTH underwent a TCM regimen and experienced dramatic improvement in symptoms and reduction in their IgE levels. This regimen appears to be effective in FPDTH population although a further study in a controlled clinical setting is required.
ALEX multiplex array is a relatively new multiplex allergy test which analyses more than 120 allergen extracts and 170 molecular components. ISAC is the most used and studied multiplex array to date, offering 112 molecular components. In ten atopic children with multiple food allergies good agreement was observed between ALEX and ISAC sIgE results for nearly all shared food components. Presence of larger number of allergens in ALEX could help clinicians to improve personalized dietary advice. However more positive sensitizations with unknown clinical relevance were found by ALEX, potentially increasing clinical complexity. Pediatric allergists should be aware of this, especially in young atopic children with (severe) eczema who have not introduced all sorts of food yet.
Abstract Background Allergy to Apis dorsata (Giant Asian Honeybee) venom is the commonest insect allergy in Sri Lanka and South East Asia. However, laboratory diagnosis is difficult as the pure venom and diagnostic reagents are not commercially available. Objective This study assessed the use of four recombinant allergens of A. mellifera venom and the passive basophil activation test in the diagnosis of A. dorsata venom anaphylaxis. Methods Serum IgE levels to four recombinant allergens of A. mellifera, rApi m 1, 2, 5 and 10 were assessed and compared with serum IgE to the crude venom of A. mellifera or V. vulgaris by Phadia ImmunoCAP, in patients who developed anaphylaxis to A. dorsata stings. Basophil activation in response to venom of A. dorsata or V. affinis was assessed using a passive basophil activation test. Association of the severity of the reaction with basophil activation was compared. Results rApi m 1 and 10 combinedly had significant correlation (r = 0.722; p < 0.001) with the crude venom of A. mellifera (Western honeybee) and a higher positivity rate of 90% (27/30). Whereas, IgE reactivity to rApi m 2 or 5 had significant correlation (p = 0.02 and p = 0.005 respectively) with V. vulgaris crude venom. All 30 (100%) were positive to A. dorsata venom in passive BAT; 70% (21/30) had over 80% activation, 96.7% (29/30) had over 60% activation and 100% had over 50% activation. Percentage activation of basophils in patients who had mild or moderate reactions (n = 20) was significantly low (p = 0.02) from that of patients who had severe reactions (n = 10). Conclusions rApi m 1 and 10 when combined was sensitive for the diagnosis of A. dorsata allergy. This combination had the lowest cross-reactivity rate with Vespula vulgaris. The passive BAT is highly sensitive in A. dorsata allergy. The basophil reactivity was significantly higher in severe anaphylaxis compared to mild/moderate anaphylaxis. This finding should be further explored in further studies.
Allergic rhinitis (AR) is very commonly caused by pollens. The symptoms of AR consist of sneezing, nasal congestion, rhinorrhea, nasal itching and airflow obstruction. The diagnosis has long been based on clinical history, skin prick tests and in vitro measurement of specific IgE, but the innovative approach of precision medicine has made diagnostic tools of much greater accuracy available. This review covers the advances in the treatment of seasonal AR concerning the drugs to be used according to the grade of disease and the characteristics of the patients, and the role of allergen immunotherapy (AIT), which is the only treatment capable of acting, in addition to the symptoms, on the cause of AR and therefore to modify its natural history. Drug treatment of AR include a large number of agents, the choice of which depends on the severity of the disease. AIT has high evidence of efficacy demonstrated by meta-analyses, and further improvement is currently apparent, as for diagnosis, applying the means of precision medicine. However, when AIT is performed in current practice, without the strict rules of controlled trials, long-term low adherence is a major problem to be solved.
Abstract Background Ifosfamide is an alkylating agent used in the treatment of a wide range of tumours. Because of known side effects it is usually administered in combination with mesna, a thiol agent with uroprotective activity, to reduce them and increase the therapeutic dose. The most frequently administered regimens for ifosfamide are fractionated doses for 3 to 5 days, high-dose intravenous bolus, and continuous infusion over 24 to 72 h. Hypersensitivity reactions to ifosfamide plus mesna are not frequently described in the literature. Moreover, no reports exist concerning desensitization for this chemotherapy combination. Case presentation A 47-year-old man with stage IV renal sarcoma was treated with the combination of ifosfamide and mesna every 3 weeks in a 4-consecutive-day infusion protocol. During the second cycle of chemotherapy, he presented acute cutaneous symptoms. A 12-step desensitization protocol was proposed in view of the lack of knowledge of the possible hypersensitivity reactions to this combination of chemotherapy agents, and the multiple difficulties found during the study of the case. Conclusions The 12-step desensitization protocol was well tolerated. Therefore, it is an appropriate and safe option in the case of suspected allergy to ifosfamide plus mesna.
Type I hypersensitivity (allergic reaction) is an unsuitable or overreactive immune response to an allergen due to cross-link immunoglobulin E (IgE) antibodies bound to its high-affinity IgE receptors (FcεRIs) on effector cells. It is needless to say that at least two epitopes on allergens are required to the successful and effective cross-linking. There are some reports pointing to small proteins with only one IgE epitope could cross-link FcεRI-bound IgE through homo-oligomerization which provides two same IgE epitopes. Therefore, oligomerization of allergens plays an indisputable role in the allergenic feature and stability of allergens. In this regard, we review the signaling capacity of the B cell receptor (BCR) complex and cross-linking of FcεRI which results in the synthesis of allergen-specific IgE. This review also discusses the protein-protein interactions involved in the oligomerization of allergens and provide some explanations about the oligomerization of some well-known allergens, such as calcium-binding allergens, Alt a 1, Bet v 1, Der p 1, Per a3, and Fel d 1, along with the effects of their concentrations on dimerization.