Asthma is commonly recognized as a heterogeneous condition with a complex pathophysiology. With advances in the development of multiple medications for patients with asthma, most asthma symptoms are well managed. Nevertheless, 5% to 10% of adult asthmatic patients (called severe asthma) are in uncontrolled or partially controlled status despite intensive treatment. Especially, severe eosinophilic asthma is one of the severe asthma phenotypes characterized by eosinophilia in sputum/blood driven by type 2 immune responses. Eosinophils have been widely accepted as a central effector cell in the lungs. Some evidence has demonstrated that persistent eosinophilia in upper and lower airway mucosa contributes to asthma severity by producing various mediators including cytokines, chemokines and granule proteins. Moreover, extracellular traps released from eosinophils have been revealed to enhance type 2 inflammation in patients with severe asthma. These novel molecules have the ability to induce airway inf lammation and hyperresponsiveness through enhancing innate and type 2 immune responses. In this review, we highlight recent insight into the function of eosinophil extracellular traps in patients with severe asthma. In addition, the role of eosinophil extracellular vesicles in severe asthma is also proposed. Finally, current biologics are suggested as a potential strategy for effective management of severe eosinophilic asthma.

Background/Aims: Sensitization to staphylococcal superantigens (SAgs) could contribute to asthma severity. However, its relevance with eosinophilic phenotype has not yet been clarified. This study aimed to investigate associations between serum specific IgE levels to SAg and eosinophilic airway inflammation in adult asthmatics. Methods: The serum specific IgE levels to 3 SAgs, including staphylococcal enterotoxin A (SEA) and B (SEB), and toxic shock syndrome toxin-1 (TSST-1) were measured by ImmunoCAP in 230 adult asthmatic patients and 50 healthy controls (HCs). Clinical characteristics and laboratory parameters, including serum total/free IgE, and 2 eosinophil-activation markers, eosinophil cationic protein (ECP), and eosinophil-derived neurotoxin (EDN), were analyzed according to blood eosinophil counts (BEC; 150 cells/μL) and serum specific IgE levels to 3 SAgs (0.35 kU/L). Results: Asthmatic patients showed higher serum specific IgE levels to 3 SAgs than HCs (p < 0.05 for all). The serum total/clinfree IgE levels were significantly higher in asthmatics with positive IgE responses to 3 SAgs than those without (p < 0.05 for all). There were no significant differences in clinical parameters including age, asthma severity, comorbidities, or smoking according to IgE responses to 3 SAgs. Patients with positive IgE responses to SEB (not to SEA/TSST-1) had higher serum specific IgE levels to house dust mites and ECP/EDN as well as higher BEC with positive correlations between serum SEB-specific IgE levels and BEC/ECP/EDN (p < 0.05 for all). Conclusions These findings suggest that serum SEB-specific IgE levels could contribute to eosinophil activation as well as IgE production in adult asthma.

Cat-pork syndrome is an uncommon food allergy induced by red meat (pork/beef) that cross-reacts with cat/dog allergens, which is mediated by immunoglobulin E (IgE) response to the cat/dog albumin component. We report 2 cases of cat-pork syndrome occurred in adult pet breeders. They had suffered from allergic rhinitis/atopic dermatitis sensitive to cat/dog dander as well as house dust mites for several years, during which an immediate type of food allergy due to red meats developed whenever taking pork or beef. ImmunoCAP results showed the increased levels of serum-specific IgE to pork and beef allergens (f26, f27) as well as cat and dog dander (e1, e5); moreover, increased level of serum-specific IgE to the cat albumin component (e224) was noted. In conclusion, cat-food allergy can be found in allergic patients among whom are sensitive to cats and dogs and develop food allergy due to red meat.

Cat-pork syndrome is an uncommon food allergy induced by red meat (pork/beef) that cross-reacts with cat/dog allergens, which is mediated by immunoglobulin E (IgE) response to the cat/dog albumin component. We report 2 cases of cat-pork syndrome occurred in adult pet breeders. They had suffered from allergic rhinitis/atopic dermatitis sensitive to cat/dog dander as well as house dust mites for several years, during which an immediate type of food allergy due to red meats developed whenever taking pork or beef. ImmunoCAP results showed the increased levels of serum-specific IgE to pork and beef allergens (f26, f27) as well as cat and dog dander (e1, e5); moreover, increased level of serum-specific IgE to the cat albumin component (e224) was noted. In conclusion, cat-food allergy can be found in allergic patients among whom are sensitive to cats and dogs and develop food allergy due to red meat.

Cat-pork syndrome is an uncommon food allergy induced by red meat (pork/beef) that cross-reacts with cat/dog allergens, which is mediated by immunoglobulin E (IgE) response to the cat/dog albumin component. We report 2 cases of cat-pork syndrome occurred in adult pet breeders. They had suffered from allergic rhinitis/atopic dermatitis sensitive to cat/dog dander as well as house dust mites for several years, during which an immediate type of food allergy due to red meats developed whenever taking pork or beef. ImmunoCAP results showed the increased levels of serum-specific IgE to pork and beef allergens (f26, f27) as well as cat and dog dander (e1, e5); moreover, increased level of serum-specific IgE to the cat albumin component (e224) was noted. In conclusion, cat-food allergy can be found in allergic patients among whom are sensitive to cats and dogs and develop food allergy due to red meat.

Cat-pork syndrome is an uncommon food allergy induced by red meat (pork/beef) that cross-reacts with cat/dog allergens, which is mediated by immunoglobulin E (IgE) response to the cat/dog albumin component. We report 2 cases of cat-pork syndrome occurred in adult pet breeders. They had suffered from allergic rhinitis/atopic dermatitis sensitive to cat/dog dander as well as house dust mites for several years, during which an immediate type of food allergy due to red meats developed whenever taking pork or beef. ImmunoCAP results showed the increased levels of serum-specific IgE to pork and beef allergens (f26, f27) as well as cat and dog dander (e1, e5); moreover, increased level of serum-specific IgE to the cat albumin component (e224) was noted. In conclusion, cat-food allergy can be found in allergic patients among whom are sensitive to cats and dogs and develop food allergy due to red meat.

Cat-pork syndrome is an uncommon food allergy induced by red meat (pork/beef) that cross-reacts with cat/dog allergens, which is mediated by immunoglobulin E (IgE) response to the cat/dog albumin component. We report 2 cases of cat-pork syndrome occurred in adult pet breeders. They had suffered from allergic rhinitis/atopic dermatitis sensitive to cat/dog dander as well as house dust mites for several years, during which an immediate type of food allergy due to red meats developed whenever taking pork or beef. ImmunoCAP results showed the increased levels of serum-specific IgE to pork and beef allergens (f26, f27) as well as cat and dog dander (e1, e5); moreover, increased level of serum-specific IgE to the cat albumin component (e224) was noted. In conclusion, cat-food allergy can be found in allergic patients among whom are sensitive to cats and dogs and develop food allergy due to red meat.

Progesterone hypersensitivity is mediated by type I, III, and IV hypersensitivity reactions to endogenous or exogenous progesterone, involving autoimmune mechanisms in females of reproductive age. It presents with a range of dermatologic manifestations, most commonly urticaria, angioedema, eczema, and maculopapular rashes. Systemic and severe symptoms, such as generalized erythema multiforme or lesions resembling severe cutaneous adverse reactions, have rarely been reported. We describe a case of a 42-year-old woman who developed drug reaction with eosinophilia and systemic symptoms (DRESS) following exogenous progesterone therapy administered for assisted reproduction. She received high-dose subcutaneous progesterone and vaginal tablets. Despite this being her first procedure, she achieved pregnancy. However, at 8 weeks of gestation and during the third month of progesterone treatment, she developed generalized erythema multiforme, pruritus, and high-grade fever. Her laboratory findings showed increased blood eosinophil counts and inflammatory markers. After oral corticosteroid (OCS) treatment for several weeks, her skin lesions were partially improved. However, after tapering of OCS, her skin lesions were aggravated with increased blood eosinophil counts. Despite daily OCS (prednisolone, 12.5–60 mg/day) treatment after childbirth, her skin symptoms and eosinophilia persisted. Reslizumab treatment was also attempted, but only the eosinophilia resolved. These clinical findings were much improved after Janus kinase (JAK) inhibitor (upadacitinib 15 mg/day) treatment; consequently, OCS was stopped. Here, we report a case of relapsing DRESS triggered by exogenous progesterone, which has been controlled by JAK inhibitor treatment.