Hypersensitivity reactions (HSRs) to iodinated contrast media (ICM) can range from mild cutaneous symptoms to life-threatening anaphylaxis. In patients with a history of ICM hypersensitivity, avoidance of the culprit agent is generally recommended. This case report describes a successful desensitization in a 56-year-old man with recurrent HSRs to multiple agents including ioversol, iohexol, iobitridol, and iopamidol. Intradermal testing was performed to identify potentially safe alternatives; however, all tested agents, including iohexol, ioversol, iobitridol, iopamidol, iodixanol, iomeprol, and iopromide, yielded positive results. Given the clinical necessity of transcatheter arterial chemoembolization, a 13-step rapid desensitization protocol with iodixanol was implemented. The procedure was completed without any breakthrough reactions. This case highlights desensitization as a feasible and effective strategy for patients with hypersensitivity to multiple ICM agents.
Rhinoviruses are the most prevalent respiratory viruses across age groups, responsible for a wide spectrum of illnesses ranging from mild upper respiratory symptoms to lower airway involvement. Moreover, rhinovirus infection is also a major driver of asthma exacerbation and development, imposing a substantial disease burden. Rhinoviruses are classified into three species: RhinovirusA, Rhinovirus B, and Rhinovirus C, each utilizing distinct host cell receptors and exhibiting different clinical patterns. RhinovirusA and Rhino-virus Care more frequently associated with clinically significant disease outcomes compared to Rhinovirus B. Rhinovirus C binds to cadherin-related family member 3 (CDHR3), and a missense variant in CDHR3 (rs6967330) increases epithelial expression of the receptor, enhancing susceptibility to infection and severe illness, particularly in early life. Rhinovirus infection induces complex immune responses, characterized by impaired interferon signaling, type 2 inflammation, and epithelial barrier disruption. In individuals with asthma, altered interferon responses and T2-high immune profiles are closely linked to rhinovirus-induced exacerbations. In infants with atopic traits, such as eosinophilia, allergen sensitization, or a family history of allergic diseases, rhinovirus infection is strongly associated with subsequent development of asthma. Rhinovirus vaccine is needed to prevent severe respiratory infections and asthma exacerbations, particularly in vulnerable populations. Rhinovirus vaccine development has been challenging due to extensive antigenic diversity and limited cross-protective immunity. Recent progress in high-valency inactivated vaccines has demonstrated the feasibility of eliciting broad neutralizing responses. Prioritizing rhinovirus types linked to greater clinical severity may enable targeted vaccine strategies for high-risk populations, offering a promising approach to reducing the global burden of rhinovirus-associated illnesses. (Allergy Asthma Respir Dis 2026;14:69-76)
Purpose: This study investigated sensitization patterns and potential cross-sensitization among tree pollens of the Betulaceae (birch, alder, hazel) and Fagaceae (oak, beech) families, based on skin prick test results. Comparisons were also made with non-tree allergens, including mugwort, cat, and cockroach. Methods: We retrospectively analyzed skin prick test results of 1,812 patients evaluated between 2010 and 2013. A positive reaction was defined as an allergen-to-histamine wheal ratio of 1.0 or higher. Sensitization rates were calculated, and cross-sensitization was assessed by analyzing simultaneous positivity rates, conditional probabilities, and Pearson correlation coefficients based on raw skin prick test scores (0, 2, 3, and 4). Results: The sensitization rates were 12.4% for birch, 11.0% for alder, 11.1% for hazel, 14.6% for oak, and 14.1% for beech. Strong correlations were observed within Betulaceae (r=0.78-0.85) and within Fagaceae (r=0.76). Moderate to strong correlations were also found between Betulaceae and Fagaceae (r=0.70-0.80), suggesting inter-family cross-sensitization. Simultaneous positivity and conditional probabilities were also high within and between Betulaceae and Fagaceae, reinforcing the observed cross-sensitization patterns. In contrast, mugwort, cat, and cockroach showed weak correlations (r= 0.35-0.37 for mugwort; r <= 0.26 for cat and cockroach) and low simultaneous positivity and conditional probabilities, indicating limited cross-reactivity. All correlations were statistically significant (P< 0.001). Conclusion: These findings demonstrate strong associations among tree pollen allergens within and between Betulaceae and Fagaceae, reflecting molecular-level cross-reactivity, supporting their clinical relevance in allergy diagnosis and treatment planning.
Episodic angioedema with eosinophilia (EAE) is a rare disorder characterized by recurrent episodes of angioedema accompanying peripheral blood eosinophilia. Oral corticosteroids (OCS) are the primary treatment; however, concerns remain regarding potential adverse effects associated with frequent or long-term use of OCS. Although the pathophysiological mechanisms underlying EAE remain unclear, studies have reported an association between T-cell clonality and subsequent elevation of interleukin (IL)-5 levels. A 43-year-old male had experienced facial and hand edema accompanied by eosinophilia since 2020. During episodes of angioedema, he exhibited febrile sensation and rapid weight gain within a few hours, along with dyspnea and severe pruritus.To control symptoms, continuous OCS therapy was required. In 2021, he was treated with anti-IL 5 antibody (reslizumab 200 mg) for 3 months, which was ineffective. Subsequently, he visited Ajou University Hospital in November 2022 for additional disease management. He had been taking deflazacort (8-32 mg/day) and cyclosporine (75-200 mg/day); however, his EAE was not controlled during which higher doses of OCS had been used. Laboratory findings revealed variations in blood eosinophils according to the symptom status and OCS dose, and general reductions in immunoglobulin G2 (IgG2), IgG3, and IgG levels due to long-term use of OCS. Since anti-interleukin (IL)-5 receptor antibody (benralizumab, 30 mg) and intravenous immunoglobulin were regularly administered at 4-week intervals, no further attacks of EAE have been observed with stopping OCS treatment. Severe EAE refractory to anti-IL-5 antibody as well as OCS therapy could be controlled by anti-IL-5 receptor antibody as an effective steroid-sparing agent.
Purpose Laryngomalacia exhibits diverse morphological patterns, severities, and comorbidities. Defining clinical phenotypes could improve management and prognosis. This study aimed to identify and characterize phenotypes using cluster analysis and to evaluate prognostic factors. Methods We retrospectively reviewed records of 195 children diagnosed with laryngomalacia between 2014 and 2023 using flexible laryngoscopy or bronchoscopy. Demographics, endoscopic findings, comorbidities, and outcomes up to 1 year of age were collected. Hierarchical cluster analysis was conducted using 10 clinical variables. Results Four phenotypes emerged: cluster 1 (n=75, 38.5%), Groningen Laryngomalacia Classification System (GLCS) type 1 dominant-mild; cluster 2 (n=35, 17.9%), GLCS type 2 dominant-mild; cluster 3 (n=40, 20.5%), severe with multiple comorbidities; and cluster 4 (n=45, 23.1%), GLCS combined-type moderate. Distinct clinical courses were observed. Cluster 3 showed the highest rates of surgical intervention (32.5%, P<0.001), pediatric intensive care unit admission (17.5%, P=0.016), and Emergency Department (ED) visits (60.0%, P=0.013) for respiratory problems during the first year. When stratified by comorbidities, children with multiple comorbidities, particularly those with major feeding problems had a higher risk of hospitalization (adjusted odds ratio [aOR], 2.65; 95% confidence interval [CI], 1.11-6.33) and ED visits (aOR, 3.17; 95% CI, 1.39-7.23), even after adjusting for sex and severity. Conclusion Four clinically meaningful phenotypes of laryngomalacia were identified from the cluster analysis based on morphology, comorbidities, and disease severity. Children with multiple comorbidities accompanied by feeding problems had the greatest risk of hospitalization and ED visits for respiratory problems within the first year, even after adjusting for the severity of laryngomalacia.
Purpose: Treatment responses to Mycoplasma pneumoniae (MP) pneumonia in children exhibit considerable variability. It is essential to identify predictive indicators and elucidate mechanisms associated with treatment responses. This study aimed to characterize the clinical, radiological, laboratory, and cytokine profiles associated with treatment responses in pediatric MP pneumonia. Methods: A retrospective analysis was performed in 85 children hospitalized with MP pneumonia between May 2019 and March 2020. Patients were categorized into the good response group (n= 74) or the poor response group (n= 11) based on clinical responses to step-wise treatment. Clinical characteristics, radiological findings, laboratory parameters, and serum levels of 27 cytokines obtained at admission were compared between the groups. Results: Compared to the good response group, the poor response group exhibited significantly longer fever duration (11.36 +/- 5.33 days vs. 5.77 +/- 3.95 days, P= 0.006), more frequent lobar consolidation (63.6% vs. 20.3%, P= 0.043), and higher lactate dehydrogenase levels (1,146 +/- 505 IU/L vs. 731 +/- 231 IU/L, P= 0.008) and MP-specific immunoglobulin M index (6.49 +/- 3.01 vs. 3.85 +/- 3.28, P= 0.014). Among the cytokines assessed, IL-21, IL-22, and IL-31 levels were significantly elevated in the good response group. IL-17A levels were also higher in this group, albeit not statistically significant. Conclusion: Early identification of clinical, laboratory, and radiologic markers may facilitate early prediction of treatment response in pediatric MP pneumonia. Elevated IL-21, IL-22, and IL-31 levels in the good response group suggest a potential role forTh17-related cytokine activity in favorable treatment outcomes, warranting further investigation in larger cohorts. (Allergy Asthma RespirDis 2026; 14:14-19)
Local anesthetics, such as lidocaine, are widely used for numbing. Adverse drug reactions related to lidocaine are variable, unpredictable, and rarely reproducible, with the exception of some typical cases. A 42-year-old female who had shown a bizarre neurological reaction after lidocaine injection for dental procedures was referred for diagnosis and safe anesthetic alternatives. Within a few minutes after exposure to lidocaine, she was unable to move any extremities or to speak, while sensory and high cranial nerve functions were preserved. She was alert and able to communicate with eye blinks. These reactions were repeatedly reproduced after intradermal injection of 2% lidocaine, with complete recovery within 1 hour without treatment. No cross-reactivity with mepivacaine or bupivacaine was observed. This is the first report of immediate and transient generalized paralysis related to lidocaine. (Al-lergy Asthma Respir Dis 2026;14:44-46)
Common variable immunodeficiency (CVID) is a heterogeneous primary immunodeficiency characterized by reduced levels of immunoglobulin (Ig)G, with or without IgA and/or IgM deficiency, and hypogammaglobulinemia. Clinical manifestations are diverse, ranging from recurrent infections to autoimmune and allergic diseases. While CVID has been rarely reported in the Korean population, particularly in adults, we report 2 adult cases of CVID comorbid with asthma and Behcet's disease. The first case of a 53-year-old with severe allergic asthma and chronic rhinosinusitis experienced recurrent respiratory infections, stomatitis, and cystitis requiring frequent antibiotic treatment. Laboratory findings indicated a T2-high asthma phenotype, with elevated serum total IgE specific IgE to dog hair and fractional exhaled nitric oxide. Immunological evaluation revealed decreased serum IgG (including IgG1 and IgG2), along with hypogammaglobulinemia. She had been treated with regular anti-IgE antibody therapy and intravenous immunoglobulin replacement therapy (IVIGRT). The second case of a 38-year-old with Beh & ccedil;et's disease and uveitis had bronchial asthma and rhinitis that were exacerbated by recurrent infections despite standard asthma therapy. Laboratory findings revealed a T2-low phenotype and a marked reduction in serum IgG (including IgG1, IgG2, and IgG4), and hypogammaglobulinemia, consistent with CVID. IVIGRT effectively reduced asthma exacerbations and infection episodes in both cases. These cases highlight the clinical heterogeneity of CVID and its potential overlap with allergic and autoimmune diseases. Immunological evaluation of underlying immunodeficiency should be considered in adult patients with asthma who present with frequent exacerbations and recurrent infections. Early diagnosis and IVIGRT can prevent complications and improve outcomes.
Purpose:This study aimed to evaluate the feasibility, safety, and immunological outcomes of low-dose cow's milk oral immunotherapy (CM OIT) in school-aged children and adolescents with severe, persistent cow's milk allergy (CMA), a group typically considered at a high risk for OIT. Methods: We conducted a retrospective study involving 12 patients (median age, 11.4 years) with immunoglobulin E (IgE)-mediated CMA, who underwent individualized low-dose CM OIT in the outpatient setting at a single tertiary hospital. Baseline and longitudinal clinical and immunological data, including casein-specific IgE and immunoglobulin G4 (IgG4) levels, were analyzed. Patients were classified as either desensitized or unsuccessful based on treatment outcomes. Results: Of the 12 patients with severe CMA, 6 achieved desensitization up to the target dose, while the remaining 6 discontinued treatment because of intolerance or poor adherence. The desensitized and unsuccessful groups showed no significant differences in baseline age, OIT starting dose, or serum casein-specific IgE level. Immunological evaluation revealed a significantly greater increase in serum casein-specific IgG4 (0.87 vs.-0.37 mg/L, P=0.004) and a significantly lower natural log-transformed fold change in the IgE/IgG4 ratio (-1.38 vs. 0.44, P= 0.008) in the desensitized group. None of the patients required epinephrine during OIT, and adverse events were generally mild. Conclusion: In selected high-risk pediatric populations with severe CMA, outpatient-based low-dose OIT using individualized flexible protocols may provide a relatively safe approach that improves tolerability and adherence. Increased casein-specific IgG4 levels and a reduced casein-specific IgE/IgG4 ratio may serve as valuable biomarkers for treatment response.
Primary antibody deficiency (PAD) is the most common form of primary immunodeficiency (PID) in adults, although the overall prevalence remains low. Recent studies have suggested a rising incidence due to changes in environmental factors and increased awareness. PID typically presents with recurrent upper and lower respiratory tract infections but may also be associated with allergic and autoimmune diseases, resulting in various clinical manifestations. This report presents three representative adult cases of PAD--linked agammaglobulinemia (XLA), common variable immunodeficiency (CVID), and IgG3 subclass deficiency (IgG3D) with bronchial asthma-offering insights into their diagnosis and long-term management. These cases emphasize the need to suspect XLA in patients with recurrent pneumonia and bronchiectasis, to recognize chronic severe urticaria as a potential clinical clue for CVID, and to evaluate IgG3D in asthma patients with frequent viral infections despite standard care.Through these examples, this clinical insight underscores the importance of early suspicion of PID, comprehensive immunological evaluation and individualized treatment strategies in improving outcomes for adult PID patients
Diffuse alveolar hemorrhage (DAH) is a rare but life-threatening condition characterized by bleeding into the alveolar spaces because of damage to the pulmonary microvasculature. While it is commonly associated with autoimmune or coagulation disorders, post-ictal DAH following a generalized tonic-clonic seizure is extremely rare, especially in pediatric populations. We report the case of a previously healthy 13-year-old boy with allergic rhinitis and buckwheat allergy who presented with his first generalized tonic-clonic seizure. Following admission, he developed dyspnea and tachypnea (respiratory rate of 38/min); on hospital day 2, oxygen desaturation (SaO(2) 88%) accompanied by hemoptysis. Laboratory tests showed no evidence of coagulopathy or autoimmune disease. Chest radiography and computed tomography revealed bilateral pulmonary infiltrates consistent with alveolar hemorrhage. Intravenous methylprednisolone (1 mg/kg for 3 days) was administered, resulting in rapid improvement of respiratory symptoms and imaging findings. This case highlights the importance of early clinical suspicion and imaging-based diagnosis of post-ictal DAH, and the necessity of prompt supportive management to achieve favorable outcomes.
Purpose: Asthma is characterized by chronic type 2/eosinophilic inflammation in the airway mucosa. This study aimed to explore the clinical value of 2 cutoffs of blood eosinophil counts (>= 300/mu L and >= 150/mu L) in eosinophilic asthma, with relation to eosinophilderived neurotoxin (EDN), a surrogate marker of eosinophilic activity. Methods: To compare clinical features and eosinophil-related mediators according to 2 cutoffs of peripheral blood eosinophil counts (>= 300/mu L and >= 150/mu L), 137 adult asthmatics who had maintained antiasthmatic medications, including inhaled corticosteroid and long-acting beta 2 agonist, without biologics, were enrolled. EDN levels in serum, urine and sputum were measured by enzymelinked immunosorbent assay. Results: Patients with asthma and higher blood eosinophil counts (>= 300/mu L) had a higher prevalence of severe asthma, chronic rhinosinusitis, partly controlled/uncontrolled status, and higher levels of sputum eosinophils and EDN in serum/sputum than those with lower blood eosinophil counts (<300/L). When compared between patients with asthma having higher blood eosinophils (>= 150/mu L) and those with lower eosinophils ( < 150/L), there were no differences in symptom severity, control status or lung function parameters. Conclusion: These findings suggest that blood eosinophil count >= 300/mu L may identify asthma patients at higher risk for severity and heightened eosinophil activity, supporting its utility as a biomarker in a real clinical setting. (Allergy Asthma Respir Dis 2026;14:20-25)
Allergen specific immunotherapy (AIT) is a well-established, disease-modifying treatment for allergic rhinitis, asthma, and Hymenoptera venom allergy. In recent years, monoclonal antibodies targeting the key mediators of type 2 immunity, such as immunoglobulin E (IgE), interleukin (IL)-4, IL-13, and thymic stromal lymphopoietin (TSLP), have emerged as a promising strategy to enhance AIT efficacy, improved safety, and enabled earlier symptom control. Anti-IgE therapy remains most well-established and widely studied, demonstrating consistent benefits in enhancing both safety and efficacy. Anti-IL-4/IL-13 receptor antibodies may contribute to improvement in immunologic profiles, although their clinical impact appears modest in a short term. Notably, the combination of AIT with anti-TSLP therapy has shown sustained immunomodulatory effects and clinical improvement lasting up to one year posttreatment. Despite these encouraging findings, the optimal dosing regimens, treatment duration, cost-effectiveness, and criteria for appropriate patient selection have not yet been clearly established. Further studies are needed to address these gaps and to guide the development of personalized therapeutic strategies for the management of allergic diseases. (Allergy Asthma Respir Dis 2025;13:138-147)
Allopurinol-induced Stevens-Johnson syndrome (SJS) is a rare but severe reaction associated with the HLA-B*58:01 allele, especially in Asian populations. Most HLA-B*58:01-negative individuals do not develop severe cutaneous adverse reactions, such as SJS, which makes the case of this patient exceptionally uncommon. Here, we report the case of a patient with allopurinol-induced SJS who tested negative for HLA-B*58:01 genotyping. Despite preemptive HLA-B*58:01 genotyping, the patient developed SJS after initiating allopurinol therapy, suggesting the possible presence of nongenetic risk factors such as renal impairment and dosing. This case report emphasizes the importance of individualized therapy and careful monitoring, even in HLA-B*58:01-negative patients. (Allergy Asthma Respir Dis 2025;13:171-173)
Purpose: We aimed to evaluate the effects of dupilumab on the change in skin symptoms and food allergen sensitization in young children with moderate-to-severe atopic dermatitis (AD). Methods: In this retrospective study, we enrolled children aged 6 months to less than 6 years who were diagnosed with moderate-to-severe AD.The dupilumab group received dupilumab treatment, while the control group was treated with topical corticosteroids, topical calcineurin inhibitors, and cyclosporine. We compared age, SCORing Atopic Dermatitis (SCORAD), Eczema Area and Severity Index (EASI), total immunoglobulin E (IgE), and specific IgE against food allergens between the groups and analyzed within-group changes. Results: Data were collected from 20 children in both the dupilumab and control groups. Significant improvements in SCORAD were observed in both groups from 6 months of age to 6 years of age (P< 0.001, P= 0.001). EASI scores were significantly improved only in the dupilumab group (P< 0.001). Significant changes in SCORAD were observed in both groups from 6 months to 23 months of age (the dupilumab group P=0.031; the control group P=0.016). The changes in SCORAD from 2 years to under 6 years of age were significant only in dupilumab group (P< 0.001). Both total IgE and specific IgE to egg white, cow's milk, wheat and peanut significantly decreased in the dupilumab group (P= 0.008 and P=0.002, respectively). Conclusion: These findings suggest that dupilumab treatment in young children on moderate-to-severe AD may reduce food allergen sensitization. (Allergy Asthma Respir Dis 2025;13:164-170)
