Recent developments in the immunopathology of COVID-19.

There has been an important change in the clinical characteristics and immune profile of Coronavirus disease 2019 (COVID-19) patients during the pandemic thanks to the extensive vaccination programs. Here, we highlight recent studies on COVID-19, from the clinical and immunological characteristics to the protective and risk factors for severity and mortality of COVID-19. The efficacy of the COVID-19 vaccines and potential allergic reactions after administration are also discussed. The occurrence of new variants of concerns such as Omicron BA.2, BA.4, and BA.5 and the global administration of COVID-19 vaccines have changed the clinical scenario of COVID-19. Multisystem inflammatory syndrome in children (MIS-C) may cause severe and heterogeneous disease but with a lower mortality rate. Perturbations in immunity of T cells, B cells, and mast cells, as well as autoantibodies and metabolic reprogramming may contribute to the long-term symptoms of COVID-19. There is conflicting evidence about whether atopic diseases, such as allergic asthma and rhinitis, are associated with a lower susceptibility and better outcomes of COVID-19. At the beginning of pandemic, the European Academy of Allergy and Clinical Immunology (EAACI) developed guidelines that provided timely information for the management of allergic diseases and preventive measures to reduce transmission in the allergic clinics. The global distribution of COVID-19 vaccines and emerging severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants with reduced pathogenic potential dramatically decreased the morbidity, severity, and mortality of COVID-19. Nevertheless, breakthrough infection remains a challenge for disease control. Hypersensitivity reactions (HSR) to COVID-19 vaccines are low compared to other vaccines, and these were addressed in EAACI statements that provided indications for the management of allergic reactions, including anaphylaxis to COVID-19 vaccines. We have gained a depth knowledge and experience in the over 2 years since the start of the pandemic, and yet a full eradication of SARS-CoV-2 is not on the horizon. Novel strategies are warranted to prevent severe disease in high-risk groups, the development of MIS-C and long COVID-19.

Cold-induced urticaria in children: A multicenter, retrospective cohort study.

Background: Studies of cold-induced urticaria (ColdU) in pediatric patients are limited and not well characterized. Objective: The objective of the study was to investigate the characteristics of ColdU in children. Methods: A multicenter, retrospective chart review was performed in children ages ≤18 years diagnosed with ColdU at 11 pediatric allergy and immunology centers in Turkey between September 1, 2010, and August 31, 2022. Results: A total of 83 children with ColdU were included, 54.2% were girls, and the mean age of symptom onset was 8.8 years. The median duration of ColdU at the time of diagnosis was significantly higher in the girls than in the boys (1.0 years [0.0-13.8 years] versus 0.3 years [0.0-15.0 years]; p = 0.007). All the patients underwent an ice cube test, and 71.1% were found positive (typical ColdU). The mean ± standard deviation age of onset was significantly higher in the patients with typical ColdU versus atypical patients (9.4 ± 4.5 years versus 7.3 ± 4.5 years; p = 0.041). Swimming alone and in combination with the wind were significantly the most reported triggers in patients with cold-induced anaphylaxis (ColdA) when compared with patients with ColdU and with nonanaphylactic symptoms (70.0% versus 28.9% [p = 0.022], and 50.0% versus 4.1% [p < 0.001], respectively). Only patients with other chronic urticaria were found to be associated with the development of typical ColdU (p = 0.036). The median total serum immunoglobulin E (IgE) was significantly higher in typical ColdU than in atypical patients (72.5 IU/mL [3.86 - 2500 IU/mL] versus 30.0 IU/mL [0.83 - 1215 IU/mL]; p = 0.007); however, total serum IgE differences were not found to affect ColdU resolution between the two groups (p = 0.204). The resolution was documented in 30.4%. Conclusion: Those who were boys and had a positive ice cube test result could have an association with earlier onset of ColdU. Those swimming alone on a windy day were at highest risk for ColdA. It is still unclear what characteristics are associated with the resolution of ColdU, and this warrants further investigation.

Risk factors for severe and critically ill COVID-19 patients: A review.

The pandemic of coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has caused an unprecedented global social and economic impact, and high numbers of deaths. Many risk factors have been identified in the progression of COVID-19 into a severe and critical stage, including old age, male gender, underlying comorbidities such as hypertension, diabetes, obesity, chronic lung diseases, heart, liver and kidney diseases, tumors, clinically apparent immunodeficiencies, local immunodeficiencies, such as early type I interferon secretion capacity, and pregnancy. Possible complications include acute kidney injury, coagulation disorders, thoromboembolism. The development of lymphopenia and eosinopenia are laboratory indicators of COVID-19. Laboratory parameters to monitor disease progression include lactate dehydrogenase, procalcitonin, high-sensitivity C-reactive protein, proinflammatory cytokines such as interleukin (IL)-6, IL-1ß, Krebs von den Lungen-6 (KL-6), and ferritin. The development of a cytokine storm and extensive chest computed tomography imaging patterns are indicators of a severe disease. In addition, socioeconomic status, diet, lifestyle, geographical differences, ethnicity, exposed viral load, day of initiation of treatment, and quality of health care have been reported to influence individual outcomes. In this review, we highlight the scientific evidence on the risk factors of severity of COVID-19.

Immune response to SARS-CoV-2 and mechanisms of immunopathological changes in COVID-19.

As a zoonotic disease that has already spread globally to several million human beings and possibly to domestic and wild animals, eradication of coronavirus disease 2019 (COVID-19) appears practically impossible. There is a pressing need to improve our understanding of the immunology of this disease to contain the pandemic by developing vaccines and medicines for the prevention and treatment of patients. In this review, we aim to improve our understanding on the immune response and immunopathological changes in patients linked to deteriorating clinical conditions such as cytokine storm, acute respiratory distress syndrome, autopsy findings and changes in acute-phase reactants, and serum biochemistry in COVID-19. Similar to many other viral infections, asymptomatic disease is present in a significant but currently unknown fraction of the affected individuals. In the majority of the patients, a 1-week, self-limiting viral respiratory disease typically occurs, which ends with the development of neutralizing antiviral T cell and antibody immunity. The IgM-, IgA-, and IgG-type virus-specific antibodies levels are important measurements to predict population immunity against this disease and whether cross-reactivity with other coronaviruses is taking place. High viral load during the first infection and repeated exposure to virus especially in healthcare workers can be an important factor for severity of disease. It should be noted that many aspects of severe patients are unique to COVID-19 and are rarely observed in other respiratory viral infections, such as severe lymphopenia and eosinopenia, extensive pneumonia and lung tissue damage, a cytokine storm leading to acute respiratory distress syndrome, and multiorgan failure. Lymphopenia causes a defect in antiviral and immune regulatory immunity. At the same time, a cytokine storm starts with extensive activation of cytokine-secreting cells with innate and adaptive immune mechanisms both of which contribute to a poor prognosis. Elevated levels of acute-phase reactants and lymphopenia are early predictors of high disease severity. Prevention of development to severe disease, cytokine storm, acute respiratory distress syndrome, and novel approaches to prevent their development will be main routes for future research areas. As we learn to live amidst the virus, understanding the immunology of the disease can assist in containing the pandemic and in developing vaccines and medicines to prevent and treat individual patients.

A compendium answering 150 questions on COVID-19 and SARS-CoV-2.

In December 2019, China reported the first cases of the coronavirus disease 2019 (COVID-19). This disease, caused by the severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2), has developed into a pandemic. To date, it has resulted in ~9 million confirmed cases and caused almost 500 000 related deaths worldwide. Unequivocally, the COVID-19 pandemic is the gravest health and socioeconomic crisis of our time. In this context, numerous questions have emerged in demand of basic scientific information and evidence-based medical advice on SARS-CoV-2 and COVID-19. Although the majority of the patients show a very mild, self-limiting viral respiratory disease, many clinical manifestations in severe patients are unique to COVID-19, such as severe lymphopenia and eosinopenia, extensive pneumonia, a "cytokine storm" leading to acute respiratory distress syndrome, endothelitis, thromboembolic complications, and multiorgan failure. The epidemiologic features of COVID-19 are distinctive and have changed throughout the pandemic. Vaccine and drug development studies and clinical trials are rapidly growing at an unprecedented speed. However, basic and clinical research on COVID-19-related topics should be based on more coordinated high-quality studies. This paper answers pressing questions, formulated by young clinicians and scientists, on SARS-CoV-2, COVID-19, and allergy, focusing on the following topics: virology, immunology, diagnosis, management of patients with allergic disease and asthma, treatment, clinical trials, drug discovery, vaccine development, and epidemiology. A total of 150 questions were answered by experts in the field providing a comprehensive and practical overview of COVID-19 and allergic disease.

The Etiology and Clinical Features of Anaphylaxis in a developing country: A nationwide survey in Turkey.

BACKGROUND: Despite the increasing frequency of anaphylaxis, there is inadequate information on the etiology and clinical features in various countries, regions and age groups, especially in developing countries. OBJECTIVE: Our aim is to assess the etiology and clinical findings of anaphylaxis in Turkey. Gathering reliable data about the etiology and clinical findings of anaphylaxis in the general population will decrease the related morbidity and mortality. METHOD: We obtained the names and phone numbers of individuals who had been prescribed an epinephrine auto-injector with a diagnosis of anaphylaxis from ministry of health. Demographic data, clinical history of the first episode of anaphylaxis including the triggering agent, clinical findings, course of hospitalization, and the management of anaphylaxis were obtained by phone survey. RESULTS: A total of 843 patients with a mean age of 21.4±17.3 years were evaluated. There was a significant male predominance among children younger than 10 years of age but a female predominance in older subjects. The most common causes of anaphylaxis were foods(40.1%) in children and bee venom(60.8%) in adults. The biphasic reaction rate was 4.3% and the median length of stay at an emergency department was 4.0 hours. Almost 60% of the patients had recurrent anaphylaxis episodes. Only 10.7% of the cases were prescribed an epinephrine auto-injector at their first anaphylaxis episode and only 59.2% of the patients were referred to an allergist during discharge from the emergency department. CONCLUSIONS: In Turkey, bee venom was the most common cause of anaphylaxis, followed by food and drug. While more than a half of patients reported recurrent attacks; only 10% had been prescribed epinephrine auto-injector kit after their first episode. Strategies to improve the anaphyalxis management are therefore urgently required.

IgE-Mediated Hypersensitivity and Desensitisation with Recombinant Enzymes in Pompe Disease and Type I and Type VI Mucopolysaccharidosis.

Enzyme replacement therapy (ERT) is important for the treatment of lysosomal storage disorders. Hypersensitivity reactions with ERT have been reported, and in these cases, desensitisation with the enzyme is necessary. Here we report the cases of 3 patients with lysosomal storage disorders, including Pompe disease and mucopolysaccharidosis type I and VI, who had IgE-mediated hypersensitivity reactions and positive skin tests. Successful desensitisation protocols with the culprit enzyme solution were used for these patients. All 3 patients were able to safely receive ERT with the desensitisation protocol.

Clinical and etiologic evaluation of the children with chronic urticaria.

BACKGROUND: Chronic urticaria (CU) is a skin disorder defined as daily or almost daily exhibition of pruritic and transient wheals that last for 6 weeks. CU is divided into two subtypes: chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIndU). OBJECTIVES: To evaluate the clinical features, possible causes, associated findings, and laboratory results of different subtypes of CU in children according to a new classification. METHODS: In this study, we evaluated the clinical features, laboratory investigations, and provocation tests of children with different subtypes of CU according to a new classification. RESULTS: Two hundred and twenty-two children (59.9% girls) were enrolled in the study. Of the study patients, 59.9% and 40.1% were diagnosed as having CSU and CIndU, respectively. Antithyroid antibody levels were positive in 7.1% of the patients with CSU, 32.8% of the children had positive 14C-urea breath test results, and 6.5% of the patients had positive stool examination results for parasites. Autologous serum skin test results were positive in 53.5% of the patients with CSU. Of the patients with CIndU, 77.5% had symptomatic dermographism, 16.8% had cold urticaria, 2.2% had cholinergic urticaria, 2.2% had solar urticaria, and 1.1% had aquagenic urticaria. CONCLUSION: Children with CSU represent the majority of patients with CU, and more than a half of these patients might have autoimmune urticaria. Symptomatic dermographism was the most common type of CIndU.

TRACK as a complementary tool to GINA and NAEPP guidelines for assessing asthma control in pre-school children.

BACKGROUND: In this study, our goal is to evaluate the consistency between TRACK and the asthma control levels assessed according to the GINA and NAEPP guidelines in children younger than 5 years of age. METHODS: Patients under 5 years old, who were followed up for recurrent wheezing for at least 1 year have been included. Parents were given the TRACK questionnaire and the control level of asthma according to GINA and NAEPP guidelines were determined by a pediatric allergist blinded to TRACK scores. Patients were classified into two groups regarding the compatibility of the control level between TRACK and both GINA and NAEPP guidelines. RESULTS: A total of 365 questionnaires were evaluated. The TRACK cut-off point of 80 provided the most consistent balance between sensitivity and specificity for the compatibility with both GINA and NAEPP (for GINA 0.763 and 0.663, kappa = 0.487, p < 0.001 and for NAEPP 0.761 and 0.769, kappa = 0.524, p < 0.001, respectively). When 80 was taken as the cut-off value for TRACK, the compatibility rate of asthma control levels between TRACK and GINA and TRACK and NAEPP was 71.0 and 76.4%, respectively. About 70.1% of the patients who had TRACK scores over 80 and had mild asthma were grouped as controlled according to GINA and 50.0% of patients who had TRACK scores over 80 and had moderate to severe asthma was grouped as uncontrolled according to GINA (p = 0.019). CONCLUSION: TRACK is compatible with NAEPP and GINA in majority of asthmatic children under 5 years of age. Nevertheless, there is a discrepancy between guidelines and TRACK scores; therefore, it should be used in conjunction with a detailed clinical examination in order to make a better decision for assessing the control levels and management plan.

Anaphylaxis/angioedema caused by honey ingestion.

Honey allergy is a very rare, but serious health condition. In this study, we presented six patients who described systemic allergic reactions after ingestion of honey. Three of the six patients had suffered from anaphylaxis. Honey-specific IgE was measured and skin-prick tests for honey were performed to diagnose honey allergy. The results of honey-specific IgE of all patients were positive. Four patients had high serum-specific IgE for honey bee venom and two of five patients had also experienced anaphylaxis due to bee stings. Skin-prick tests with honey and pollens were positive in five patients. Honey is one of the foods that can cause severe systemic reactions. Specific IgE and skin-prick tests are helpful for the diagnosis of honey allergy.

The evaluation of drug provocation tests in pediatric allergy clinic: a single center experience.

Drug provocation tests (DPTs) are gold standard to diagnose drug allergy. Our goal was to evaluate the results and safety of diagnostic methods including DPTs during childhood. Between January 2010 and February 2013 DPTs were performed and evaluated, prospectively, in children who attended our pediatric allergy clinic with a suspected drug hypersensitivity reaction. One hundred ninety-eight suspected drug reactions in 175 patients (88 boys and 87 girls) were evaluated. The median age of the subjects at the time of the suspected drug-induced hypersensitivity reaction and at the time of the study was 56 (interquartile range [IQR] = 24-120 months) months and 76 (IQR = 35-149 months) months, respectively. Suspected drugs were beta-lactam antibiotics in 108 cases (54.5%), non-beta-lactam antibiotics in 22 cases (11.1%), and nonsteroid anti-inflammatory drugs in 52 cases (26.3%). The history was compatible with immediate-type reactions in 69 cases (34.8%). Skin-prick tests were not positive in any of the cases. Intradermal tests were positive in three cases (4%). DPTs were positive in 13 (6.8%) of 191 provocation cases, which were performed with culprit drugs. Our results suggest that a positive clinical history is not enough to make a diagnosis of drug allergy, which highlights the significance of undertaking further diagnostic evaluation especially for DPTs.

The effect of obesity on the level of fractional exhaled nitric oxide in children with asthma.

BACKGROUND: Several studies have demonstrated a relationship between asthma and obesity. However, the results have been conflicting with regard to the relationship between fractional exhaled nitric oxide (FeNO), used as a marker of airway inflammation in asthmatic patients, and obesity. We aimed to evaluate the association of FeNO with obesity and obesity-related metabolic complications in asthmatic and nonasthmatic children. METHODS: The study population included children aged between 6 and 17 years and consisted of 4 groups: obese asthmatics (n = 52), normal-weight asthmatics (n = 49), obese nonasthmatics (n = 51) and normal-weight nonasthmatics (n = 42). FeNO measurement and spirometry were performed for all patients. To evaluate the metabolic complications, serum lipids, glucose and insulin levels were measured. Insulin resistance (IR) was estimated by the homeostasis model assessment, HOMA-IR. All participants were evaluated for the presence of metabolic syndrome (MS). RESULTS: The mean age for the 194 subjects participating in the study was 11.6 ± 2.5 years. The FeNO level of asthma patients with MS was not different from those without MS (14.5 ± 8.0 and 16.7 ± 8.7, respectively, p = 0.449). In the nonasthmatic group, subjects with MS had a higher FeNO level than subjects without MS (12.5 ± 5.1 and 17.3 ± 8.3, respectively, p = 0.014). Spearman's rank correlation coefficients revealed a positive correlation between FeNO and body mass index (BMI; p = 0.049, r(2): 0.204) in the nonasthmatic group and after multivariate regression analysis, BMI still persisted as an independent risk factor for FeNO. CONCLUSION: We found a positive correlation between BMI and FeNO level which suggests a link between obesity and increased airway inflammation in nonasthmatic children.

Characteristics of anaphylaxis in children referred to a tertiary care center.

Anaphylaxis is a potentially life-threatening condition. There are limited data about the etiology and the clinical characteristics in developing countries. This study aimed to investigate the clinical characteristics of anaphylaxis patients attending our pediatric allergy clinic. We conducted a prospective analysis of patients who were admitted to our allergy clinic for anaphylaxis from 2010 to 2012. Ninety-six patients were evaluated during the study period. The mean age was 7.4 ± 5.2 years. Venom, food, and drugs were the most common causative agents responsible for 31 (32.3%), 30 (31.3%), and 26 (27.1%) of the cases, respectively. Foods implicated most frequently were peanuts and nuts (n = 9; 30.0%), cow's milk (n = 7; 23.3%), and egg white (n = 6; 20.0%). The clinical manifestations during anaphylaxis in order of frequency were cutaneous (97.9%), respiratory (86.5%), gastrointestinal (42.7%), neurological (37.5%), and cardiovascular symptoms (30.2%). A biphasic course was noticed in five cases (5.2%). Of the 91 patients, 79 (86.8%) received H1-antihistamines, 73 (80.2%) received corticosteroids, 40 (44.4%) received adrenaline, 38 (41.8%) received fluid replacement therapy, 18 (19.8%) received ß2-mimetics, and 8 (8.8%) received H2-antihistamines. According to severity, 7.3% of patients had mild, 59.4% had moderate, and 33.3% had severe anaphylaxis. Food and bee venom allergy were the most common etiologies. Adrenaline, the first-line treatment of anaphylaxis, was administered in only 44.4% of our cases.

Vitamin D level in children is correlated with severity of atopic dermatitis but only in patients with allergic sensitizations.

Vitamin D is believed to affect the progression and severity of atopic dermatitis (AD). Allergic sensitization may cause this effect to vary. Individuals who fulfilled the Hanifin and Rajka criteria for AD underwent epidermal prick tests and blood tests for specific immunoglobulin E(IgE), serum total IgE, 25-hydroxy vitamin D, and peripheral blood eosinophil count and percentage. Disease severity was determined according to the Scoring Atopic Dermatitis (SCORAD) index. Patients were grouped according to allergic sensitization. Seventy-three children with AD (median age 33.0 mos, interquartile range 19.0-61.5 mos) were enrolled in the study; 33 (45.2%) were found to have allergic sensitization. In this group there was a negative correlation between SCORAD score and serum vitamin D level (p = 0.047, correlation coefficient [r] = -0.349), whereas there was no correlation in the group without sensitization (p = 0.30, r = -0.168). Vitamin D was not correlated with total IgE and eosinophil percentage in either AD group (p = 0.77, r = 0.054 and p = 0.73, r = -0.062, respectively). Vitamin D may affect the severity of AD, especially in children with allergic sensitization.

Characteristics of children with non-hodgkin lymphoma associated with primary immune deficiency diseases: descriptions of five patients.

BACKGROUND: An increased incidence of non-Hodgkin lymphoma (NHL) has been seen in various primary immune deficiency (PID) cases. The present study aimed to evaluate the clinical characteristics and treatment outcomes of five cases with NHL associated with primary immunodeficiency. METHODS: We retrospectively evaluated five patients with primary immunodeficiency who developed NHL. Two patients had ataxia-telangiectasia (A-T), one patient had common variable immunodeficiency (CVID), one patient had Bloom's Syndrome, and one patient had Wiskott-Aldrich syndrome (WAS). RESULTS: All patients were male (median age, 8 years). Stage distribution was stage III in three patients and stage IV in two patients. Three patients had B-cell lymphoma and two had T-cell lymphoma. Reduced doses of Berlin-Frankfurt-Münster (BFM) and French Society of Pediatric Oncology (SFOP) regimens were used in four patients according to histopathological subtype. The two patients with ataxia and one patient with Bloom's Syndrome died of progressive/relapsed disease at months 5, 19, and 6, respectively. The patient with CVID associated with T-cell lymphoma has been in remission for 7 years. A full-dosage regimen of rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) was successfully used in the patient with WAS and B-cell lymphoma; he was still in remission after 3 years. CONCLUSION: Primary immunodeficiency diseases are one of the strongest known risk factors for the development of NHL. Management of these patients remains problematic. There is a great need to develop new therapeutic approaches in this group. The use of rituximab in combination with CHOP may provide a promising treatment option for B-cell lymphomas associated with immunodeficiency.

Consistency of GINA criteria and childhood asthma control test on the determination of asthma control.

BACKGROUND: Reliable assessment of asthma control is essential for effective treatment. Although several methods are used to assess asthma control, it is still suboptimal all over the world. Childhood asthma control test (C-ACT) is a widely used complementary test in determining the level of asthma control in conjunction with GINA guidelines. OBJECTIVE: To evaluate the consistency between the childhood asthma control test (C-ACT) and the Global Initiative for Asthma (GINA) guideline-based asthma control measure in children with asthma and, if present, to investigate the reasons for any discrepancy. METHODS: Patients and their caregivers filled a C-ACT and a socioeconomic status survey before the physician visit. Asthma control level was also assessed according to GINA criteria by a pediatric allergist who was blinded to C-ACT scores. RESULTS: The mean age of the total 314 patients was 9.0 ± 1.9 yr, ranging between 4.3 and 11.8 yr, of whom 56.1% (n = 176) were men. Regarding the study group, 54.8% of patients were controlled according to GINA, and 51.0% of patients were controlled according to C-ACT (score ≥20). There was inconsistency between GINA and C-ACT in 26.7% (84/314) of the study group when the patients were evaluated individually (κ = 0.464). There was not any significant variable that could predict the consistency and inconsistency between these methods. CONCLUSION: Consistency between GINA and C-ACT is not as to be expected. Using only one method for determining the control level of asthma does not seem to be reliable and accurate.

Localized acute generalized exanthematous pustulosis with amoxicillin and clavulanic acid.

Acute generalized exanthematous pustulosis (AGEP) is a rare skin disorder, characterized by acute development of numerous, pin-head sized, nonfollicular pustules on erythematous skin, with high fever and neutrophilia. The condition is frequently caused by hypersensitivity reaction to drugs or viral infections. Diagnosis is established according to clinical and histological criteria. Herein, we report a 17-year-old girl with localized AGEP related to the use of amoxicillin-clavulanate.

A pediatric case of anaphylaxis due to octreotide.

Octreotide is an octapeptide that mimics natural somatostatin pharmacologically. It is a potent inhibitor of growth hormone, glucagon and insulin, which is used for treatment of acromegaly, symptomatic treatment of carsinoid tumours, and vasoactive intestinal peptide secreting tumors. It is also used for chylothorax, chemotherapy induced diarrhea and, as it inhibits the exocrine production of pancreatic enzymes, for acute and chronic pancreatitis. Gallbladder stones, diarrhea, nausea, vomiting, hypoglycemia/hyperglycemia, headache, and abdominal discomfort are some of the common adverse effects of octreotide and it may rarely cause anaphylaxis. We present here a child who had chronic pancreatitis and had an anaphylactic reaction to octreotide. To our knowledge this is the first pediatric case of anaphylaxis with octreotide who was successfully desensitized.

Recent advances and developments in COVID-19 in the context of allergic diseases.

BACKGROUND: Since the first reports of coronavirus disease 2019 (COVID-19) in Wuhan, China, in December 2019, there have been 198 million confirmed cases worldwide as of August 2021. The scientific community has joined efforts to gain knowledge of the newly emerged virus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the immunopathological mechanisms leading to COVID-19, and its significance for patients with allergies and asthma. METHODS: Based on the current literature, recent advances and developments in COVID-19 in the context of allergic diseases were reviewed. RESULTS AND CONCLUSIONS: In this review, we discuss the prevalence of COVID-19 in subjects with asthma, attacks of hereditary angioedema, and other allergic diseases during COVID-19. Underlying mechanisms suggest a protective role of allergy in COVID-19, involving eosinophilia, SARS-CoV-2 receptors expression, interferon responses, and other immunological events, but further studies are needed to fully understand those associations. There has been significant progress in disease evaluation and management of COVID-19, and allergy care should continue during the COVID-19 pandemic. The European Academy of Allergy & Clinical Immunology (EAACI) launched a series of statements and position papers providing recommendations on the organization of the allergy clinic, handling of allergen immunotherapy, asthma, drug hypersensitivity, allergic rhinitis, and other allergic diseases. Treatment of allergies using biologics during the COVID-19 pandemic has also been discussed. Allergic reactions to the COVID-19 vaccines, including severe anaphylaxis, have been reported. Vaccination is a prophylactic strategy that can lead to a significant reduction in the mortality and morbidity associated with SARS-CoV-2 infection, and in this review, we discuss the proposed culprit components causing rare adverse reactions and recommendations to mitigate the risk of anaphylactic events during the administration of the vaccines.