Challenge-proven aspirin hypersensitivity in children with chronic spontaneous urticaria

Diagnostic evaluation of hypersensitivity reactions to arylpropionic acid derivatives: a descriptive observational study focusing on clinical characteristics and potential risk factors in children

BACKGROUND

Arylpropionic acid derivatives (APs) are the main triggers of nonsteroidal anti-inflammatory drug (NSAID) hypersensitivity. Data on clinical patterns and risk factors for AP hypersensitivity in children are quite limited.

AIM

To assess the clinical characteristics and potential risk factors for proven AP hypersensitivity in children.

METHOD

Patients with a history of AP hypersensitivity were retrospectively assessed using a standardized diagnostic algorithm. Children with confirmed hypersensitivity were defined as selective responders or cross-intolerants based on the result of drug provocation tests and further categorized according to the EAACI/ENDA classification. A multivariable logistic regression analysis was performed to analyze the potential risk factors for proven AP hypersensitivity.

RESULTS

A total of 166 patients (51.2% male, median age of six years) with a history of AP hypersensitivity were included. Ibuprofen (89.2%) was the most frequently reported AP in the patients' histories. The reported hypersensitivity of 40 (22.4%) patients was confirmed by diagnostic testing: eight (13.6%) patients with a history of reaction only to APs and 32 (29.9%) patients with a history of reactions to multiple NSAIDs, including chemically unrelated NSAIDs in addition to APs. Five (12.5%) patients were classified as selective responders and 35 (87.5%) were cross-intolerants. Overall, five (12.5%) of the confirmed cases could not be categorized according to the EAACI/ENDA classification. Older age (aOR: 1.11, 95% CI 1.02-1.21, p = 0.015), chronic urticaria as an underlying disease (aOR: 2.87, 95% CI 1.09-7.54, p = 0.033) and a history of anaphylaxis (aOR: 7.84, 95% CI 1.86-33.04, p = 0.005) were related to confirmed AP hypersensitivity.

CONCLUSION

Almost a quarter of children and adolescents were confirmed to have AP hypersensitivity. Older age, the presence of chronic urticaria and a history of anaphylaxis were potential risk factors for proven AP hypersensitivity.

The many faces of pediatric urticaria

Urticaria is a common disease that can affect individuals of all age groups, with approximately one-quarter of the population experiencing it at least once in their lifetime. Lesions characterized by erythema and itchy hives can appear anywhere on the body. These can vary in size ranging from millimeters to centimeters, and typically clear within 24 h. About 40% of patients with urticaria have accompanying angioedema, which involves localized deep tissue swelling. Urticaria usually occurs spontaneously and is classified into acute and chronic forms, with the latter referring to a condition that lasts for more than 6 weeks. The prevalence of chronic urticaria in the general population ranges from 0.5% to 5%, and it can either be inducible or spontaneous. The most common form of pediatric urticaria is acute and is usually self-limiting. However, a broad differential diagnosis should be considered in children with urticaria, particularly if they also have accompanying systemic complaints. Differential diagnoses of pediatric urticaria include chronic spontaneous urticaria, chronic inducible urticaria, serum sickness-like reaction, urticarial vasculitis, and mast cell disorders. Conditions that can mimic urticaria, including but not limited to cryopyrinopathies, hyper IgD syndrome, Periodic Fever, Aphthous Stomatitis, Pharyngitis and Adenitis (PFAPA), Tumor Necrosis Factor Receptor Associated Periodic Syndrome (TRAPs), and Schnitzler syndrome should also be considered. The many faces of pediatric urticaria can be both easy and confusing. A pragmatic approach relies on clinical foresight and understanding the various forms of urticaria and their potential mimickers. This approach can pave the way for an accurate and optimized diagnostic approach in children with urticaria.

NSAID Hypersensitivity in the Pediatric Population: Classification and Diagnostic Strategies

Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most frequently administered drugs, mainly for their anti-pyretic, but also for pain-relieving and anti-inflammatory effects in children. NSAIDs are composed of structurally divergent subgroups of drugs with similar pharmacological and adverse effects. Aspirin originates from salicin and was the first synthesized analgesic. As a prototype of NSAIDs; aspirin-induced hypersensitivity reactions were first reported, but subsequently, other phenotypes of hypersensitivity reactions were also described with aspirin and other NSAIDs. There are certain challenging aspects of NSAID-hypersensitivity in the pediatric population that need to be further investigated. These include the effect of age on drug metabolism and the natural history of the various phenotypes of NSAID-hypersensitivity, the effect of certain co-factors (infections, exercise) on NSAID-hypersensitivity, and diagnostic clinical and laboratory biomarkers clarifying the endotypes. In recent years, a non-negligible number of case series, studies and expert panel reports have been published in this field with some novel features and diagnostic modalities in the pediatric population. With the current review; the clinical phenotypes and diagnostic and management modalities of suspected NSAID-induced hypersensitivity reactions in childhood and adolescence were explained and updated by examining past and current publications.

Urticaria and angioedema in children and adolescents: diagnostic challenge

Urticaria diagnosis may be challenging in children since it can be triggered or related to numerous conditions. In this paper, we reviewed the main aspects regarding the diagnosis of urticaria in the pediatric population. Acute urticaria is often due to viral infections. However, other culprits, including foods, insect stings, drugs, contrast media, vaccination, latex, and medical diseases, may account for acute patterns. Laboratory tests and confirmatory allergy tests should be individualized and guided by history. Chronic urticaria (CU) is defined when hives and/or angioedema last for more than 6 weeks. The most common type of chronic urticaria in children is chronic spontaneous urticaria (CSU). Chronic inducible urticaria (CindU) is less common but is important to diagnose in order to manage appropriately and reduce the risk of severe reactions. Inducible forms in children are often diagnosed with specific provocation tests similar to the tests used in adults. Given that chronic urticaria could rarely be a presentation of vasculitis, systemic-onset juvenile idiopathic arthritis, or auto-inflammatory syndromes, it is important to rule out these conditions. It is crucial to differentiate cases of chronic urticaria from mastocytosis and Bradykinin-mediated angioedema, given that treatment may differ. The management of chronic urticaria in children has improved over the last decade because of the development of both clear management guidelines and new effective drugs. It is crucial to increase awareness for appropriate diagnosis and new available treatment to improve the management of chronic urticaria in children.

Chronic spontaneous urticaria: An etiopathogenic study

Importance:

Exact etiopathogenesis of chronic spontaneous urticaria (CSU) remains elusive. Infections, pseudoallergens, autoimmunity, and contact sensitization are various postulated factors. Few studies are available measuring cytokine levels in CSU.

Objectives:

The aim was to study various etiological factors of CSU and levels of IL-6 and IFN-ϒ in cases and controls, and correlation between various etiologies with the levels of the abovementioned interleukins in the cases.

Design:

Case-control study performed over 2 years with no follow-up of the participants.

Setting:

It was a referral-center-based study.

Participants:

Sixty patients of CSU and equal age and sex-matched healthy controls were recruited on the basis of convenience sampling.

Exposures:

Biochemical and hematological investigations with hepatitis serology, thyroid function tests, anti-thyroid antibodies, and levels IL-6 and IFN-ϒ were performed in all cases and controls. All cases were subjected to ASST. Cases with all above negative tests were patch-tested with Indian standard series. Urticaria activity score (UAS7) was calculated for all the cases and repeated in patients with positive etiological factor after 3 weeks (improvement after allergen or drug avoidance, treatment of infection).

Outcomes:

To study the various etiological factors (food, infection, autoimmunity, autoreactivity, and contact sensitization) and the levels of IL-6 and IFN- γ in patients of chronic spontaneous urticaria.

Results:

Etiology was ascertained in 75% of patients (autoimmunity: 50%, contact sensitization: 21.67%, food and drug allergy: 1.67% each). Mean values of the interleukins and anti-thyroid antibodies were significantly higher in cases versus controls. Levels of IFN-ϒ were significantly elevated in patients with higher UAS7 scores.

Conclusion:

Antithyroid antibodies, ASST, and patch testing are important tools and should be considered in patients of CSU after a thorough history and history-based workup. Elevated levels of IL-6 and IFN- ϒ in cases suggest that both Th1 and Th2 type of immune responses are implicated in pathogenesis of CSU.

Aspirin-Induced Delayed Urticaria in Children with Kawasaki Disease: A Retrospective Case-Control Study

Background

Aspirin remains a key component of the standard therapy for Kawasaki disease (KD) in children. Although it is well known that aspirin can cause hypersensitivity such as aspirin-induced urticaria (AIU), AIU in children with KD has not been described.

Methods

A retrospective case-control study was conducted to investigate AIU clinical features, biochemical parameters, treatment and outcomes in children with KD. Furthermore, biomarkers for predicting AIU were explored using the receiver operating characteristic (ROC) curve analysis.

Results

We identified 46 AIU cases with 22 boys and 24 girls during April 2015–May 2019. Eighty-nine age-matched KD patients without AIU were randomly chosen as controls. The proportions of children with allergy history and aspirin doses administered in the 2 groups were found not to be significantly different. AIU group had substantially higher baseline C-reactive protein and NT-proBNP levels, and increased neutrophil percent. AIU appeared 6.0 (4.0, 8.0) days after aspirin treatment. Aspirin withdrawal and anti-allergic treatment were applied for AIU, and AIU disappeared in 1–3 days. Baseline NT-proBNP predicted AIU with an AUC of 0.70 (95% CI [0.60 to 0.79]) for sensitivity and specificity of 72.1% and 62.5%, respectively, for a cut-off value of 612.9 mg/L. The length of hospital stay for AIU patients was significantly greater compared with controls.

Conclusion

AIU in KD children is not related to gender or aspirin dose, and those with AIU have more severe inflammation at admission. Aspirin should be withdrawn for AIU management. Baseline NT-proBNP may serve as a valuable biomarker to predict AIU.

Pediatric Drug Allergies: Updates on Beta-Lactam, Nonsteroidal Anti-Inflammatory Drug, and Chemotherapeutic Reactions

Adverse drug reactions are frequently reported in pediatric patients. In this review article, the authors discuss pediatric drug allergies with emphasis on the most common culprits, beta-lactam antibiotics and non-steroidal anti-inflammatory drugs. The authors also discuss reactions to non-beta-lactam antibiotics and chemotherapeutics. Skin testing has not yet been validated for many drugs, although notable exceptions include penicillin and carboplatin. The gold standard for diagnosis in most cases remains drug challenge, and the need for penicillin skin testing prior to oral provocation challenge has been questioned in recent studies. Successful desensitizations have also been reported with several drugs.

Effectiveness of Personalized Low Salicylate Diet in the Management of Salicylates Hypersensitive Patients: Interventional Study

Salicylic acid and its derivatives (including acetylsalicylic acid/aspirin) are popular in medicine. They also occur naturally in many food products. The aim of the study was to investigate the effect of the personalized low salicylate diet (PLSD) on the reduction of asthma, rhinosinusitis and urticaria symptoms in patients with hypersensitivity to aspirin (ASA) or nonsteroidal anti-inflammatory drugs (NSAIDs). To achieve the research goal, a prospective, nonrandomized, baseline-controlled intervention study was conducted. Thirty patients diagnosed with NSAIDs hypersensitivity, who despite pharmacotherapy had symptoms of hypersensitivity, were included in the study. The PLSD was recommended for all participants for a period of two to four weeks. The intensity of subjectively declared symptoms of asthma, rhinosinusitis and urticaria were measured before and after dietary intervention, using, respectively, the asthma control test (ACT), the sino-nasal outcome test (SNOT-22) and the four-item itch questionnaire (FIIQ). Diet adherence and salicylate intake were measured by a 3-day food record. The severity of symptoms improved significantly after the intervention. The median of the ACT score was 24 scores before and 25 after the dietary intervention (p < 0.002), the median of the SNOT-22 score was 25 before and 13 after a dietary intervention (p < 0.0002) and the median of the FIIQ score was 5 before and 0 after a dietary intervention (p < 0.0002). The intake of salicylates decreased from 0.79 mg/day (before intervention) to 0.15 mg/day (p < 0.001) (during intervention). Although the usefulness of a low salicylate diet in the treatment of salicylate hypersensitivity is controversial, the results of our study indicate that the PLSD may have a positive effect in reducing symptoms of salicylate hypersensitivity and could be an additional tool supporting the therapy of these patients.

Presence of positive skin prick tests to inhalant allergens and markers of T2 inflammation in subjects with chronic spontaneous urticaria (CSU): a systematic literature review

BACKGROUND

Current guidelines do not recommend performing aeroallergen skin prick testing (SPT) in chronic spontaneous urticaria (CSU).

OBJECTIVE

The objective of this review was to investigate the presence of aeroallergen sensitization and markers of T2 inflammation in subjects with CSU.

METHODS

Systematic literature reviews to identify all studies that evaluated the presence of T2 markers of allergic inflammation in CSU subjects were performed.

RESULTS

In 16 studies that assessed the prevalence of positive SPT to multiple aeroallergens in CSU, 38.5% of CSU subjects had positive SPT. In three controlled studies, 34.2% of CSU subjects had positive SPT to multiple aeroallergens, compared to 13.6% of controls (p = 0.047). In 18 studies that assessed the prevalence of house dust mite (HDM) positive SPT in CSU, 27.5% of CSU subjects had positive SPT. In three controlled studies, 27.5% of CSU subjects had positive SPT to HDM, compared to 2.1% of controls (p = 0.047). Overall, CSU subjects were 3.1 times more likely to be aeroallergen-sensitized (95% CI 1.7-5.8, p = 0.0002) and 6.1 times more likely to be HDM-sensitized (95% CI 3.7-9.9, p < 0.00001) than controls. Mean total serum IgE (tIgE) levels were 238 kU/L and median tIgE levels were 164 kU/L, which was greater than the upper 90th percentile of normal (< 137 kU/L). Compared to healthy controls, CSU subjects were 6.5 times more likely to have IgG autoantibody against FcεR1α (p = 0.001), 2.4 times more likely to have IgG anti-IgE antibody (p = 0.03) and 5 times more likely to have anti-thyroid peroxidase (anti-TPO) antibody (p = 0.02). When corticosteroids were withheld for ≥ 28 days, mean blood eosinophil percentage was elevated at 5.9% (normal < 4%), but other studies reporting absolute count found the mean was in the normal range, 239 × 10 6 / L (normal < 400 × 10 6 / L).

CONCLUSION

Increased aeroallergen sensitization, tIgE, autoantibodies and blood eosinophil percentage in the CSU subjects indicates the possible importance of T2 inflammation in the pathogenesis of CSU. Further studies may be warranted to determine if specific allergen avoidance, desensitization or improvement in the mucosal allergic inflammation present in asthma and/or rhinitis has any benefit in the management of CSU.

Pharmacologic Management of Chronic Urticaria in Pediatric Patients: The Gap Between Guidelines and Practice

Chronic urticaria is an uncommon disorder in children but can present considerable morbidity, as well as frustration for the healthcare provider and parent. The prevalence is 0.1-0.3% but can vary considerably by country. Chronic spontaneous urticaria (no identifiable cause) is responsible for 70-80% of chronic urticaria, about half of this due to a subtype called chronic autoimmune urticaria identified by the presence of autoantibodies to IgE or the IgE receptor. Chronic urticaria that is triggered by external physical stimuli is called chronic inducible urticaria and is present in another 15-20%. Allergies, infection, and other underlying diseases such as thyroid disease, celiac disease, or Helicobacter pylori infection cause a minor proportion of cases. Chronic urticaria has considerable impact on quality of life and healthcare costs. An adverse impact on quality of life is more prevalent in older children and adolescents and can be comparable to other diseases of childhood such as diabetes and epilepsy. Healthcare costs can be 50% higher than the national estimates for healthy patients and include more hospitalizations, longer duration of hospitalizations, and more emergency department (ED) and outpatient visits. Allergic and autoimmune diseases can be comorbidities that add to healthcare utilization. Resolution can take years. Guidelines are available for diagnosis and treatment. A good history is the key to identifying the cause. Minimal laboratory tests are required and should be guided by the history. Patients with easily controlled urticaria may not need any laboratory tests. Suggested treatment emphasizes the use of non-sedating antihistamines, utilized in a step-wise fashion beginning with normal doses and advancing the dose based on the response up to four times the recommended dose for age. Other treatments are left to the urticaria specialist and are not discussed in this paper. These guidelines are not well utilized based on real-world studies; sedating antihistamines and oral steroids are overutilized. Medications should be taken daily, not as needed. Additional medications, if required, should be added to prior medications in a step-wise fashion. The gap between the guidelines for diagnosis and treatment and what is happening in the real world needs to be closed to reduce the cost and morbidity associated with this disorder.

Pediatric Drug Allergies: Updates on Beta-Lactam, Nonsteroidal Anti-Inflammatory Drug, and Chemotherapeutic Reactions

Adverse drug reactions are frequently reported in pediatric patients. In this review article, the authors discuss pediatric drug allergies with emphasis on the most common culprits, beta-lactam antibiotics and non-steroidal anti-inflammatory drugs. The authors also discuss reactions to non-beta-lactam antibiotics and chemotherapeutics. Skin testing has not yet been validated for many drugs, although notable exceptions include penicillin and carboplatin. The gold standard for diagnosis in most cases remains drug challenge, and the need for penicillin skin testing prior to oral provocation challenge has been questioned in recent studies. Successful desensitizations have also been reported with several drugs.

Management of chronic urticaria in children: a clinical guideline

The aim of this guidance is to provide recommendations to clinicians and other interested parties on chronic urticaria in children. The Italian Society for Pediatrics (SIP), the Italian Society for Allergy and Immunology (SIAIP), the Italian Society for Pediatric dermatology (SIDerP) convened a multidisciplinary panel that prepared clinical guidelines for diagnosis and management of chronic urticaria in childhood. Key questions on epidemiology, natural history, diagnosis, and management were developed. The literature was systematically searched and evaluated, recommendations were rated and algorithms for diagnosis and treatment were developed. The recommendations focus on identification of diseases and comorbidities, strategies to recognize triggering factors, improvement of treatment by individualized care.

NSAID-induced reactions: classification, prevalence, impact, and management strategies

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the leading cause of hypersensitivity drug reactions. The different chemical structures, cyclooxygenase 1 (COX-1) and/or COX-2 inhibitors, are taken at all ages and some can be easily obtained over the counter. Vasoactive inflammatory mediators like histamine and leukotriene metabolites can produce local/systemic effects. Responders can be selective (SR), IgE or T-cell mediated, or cross-intolerant (CI). Inhibition of the COX pathway is the common mechanism in CI, with the skin being the most frequent organ involved, followed by the lung and/or the nose. An important number of cases have skin and respiratory involvement, with systemic manifestations ranging from mild to severe anaphylaxis. Among SR, this is the most frequent entity, often being severe. Recent years have seen an increase in reactions involving the skin, with many cases having urticaria and/or angioedema in the absence of chronic urticaria. Aspirin, the classical drug involved, has now been replaced by other NSAIDs, with ibuprofen being the universal culprit. For CI, no in vivo/in vitro diagnostic methods exist and controlled administration is the only option unless the cases evaluated report repetitive and consistent episodes with different NSAIDs. In SR, skin testing (patch and intradermal) with 24-48 reading can be useful, mainly for delayed T-cell responses. Acetyl salicylic acid (ASA) is the test drug to establish the diagnosis and confirm/exclude CI by controlled administration. Desensitization to ASA has been extensively used in respiratory cases though it can also be applied in those cases where it is required.

Characteristics of NSAID-induced hypersensitivity reactions in childhood

Non-steroidal anti-inflammatory drugs (NSAIDs) are available as over-the-counter drugs, and they are commonly used in children for their antipyretic, analgesic, and anti-inflammatory effects. NSAIDs are among the most frequently reported drugs associated with hypersensitivity reactions and even with anaphylaxis. A complete evaluation of the patients based on reported clinical manifestations, timing of the reaction, the presence of underlying disease, and reactions to other NSAIDs allows clinicians to stratify children with a history of reaction to NSAIDs. Although NSAID-induced hypersensitivity reactions have mainly been investigated in adults, recent studies have aimed to explore their epidemiology in the pediatric population. This review will cover the current understanding of clinical manifestations, the risk factors, and the different phenotypes of NSAID-induced hypersensitivity reactions with a comprehensive overview of the epidemiologic data from past to present and the practical approach to the management of NSAID hypersensitivity in children and adolescents.

Chronic urticaria and drug hypersensitivity in children

The cause of chronic urticaria remains often elusive. The association between chronic urticaria and intake of medications have been reported in children. However, the causative role of drugs has been rarely ascertained by onset of symptoms on drug provocation test. Chronic urticaria can be mediated by immunologic and nonimmunologic mechanisms. The diagnostic work-up of chronic urticaria includes a comprehensive evaluation of triggering factors such as drugs. A diagnosis is necessary in order to permit a safely administration of drugs in children with chronic urticaria.

EAACI/ENDA Position Paper: Diagnosis and management of hypersensitivity reactions to non-steroidal anti-inflammatory drugs (NSAIDs) in children and adolescents

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in the pediatric population as antipyretics/analgesics and anti-inflammatory medications. Hypersensitivity (HS) reactions to NSAID in this age group, while similar to adults, have unique diagnostic and management issues. Although slowly accumulating, published data in this age group are still relatively rare and lacking a unifying consensus. This work is a summary of current knowledge and consensus recommendations utilizing both published data and expert opinion from the European Network of Drug Allergy (ENDA) and the Drug Hypersensitivity interest group in the European Academy of Allergy and Clinical Immunology (EAACI). This position paper summarizes diagnostic and management guidelines for children and adolescents with NSAIDs hypersensitivity.

Management of Pediatric Urticaria with Review of the Literature on Chronic Spontaneous Urticaria in Children

There are substantial knowledge gaps related to diagnosis and management of pediatric cases of chronic urticaria, and in particular chronic spontaneous urticaria (CSU). In this article we aimed to review the diagnosis and management of chronic urticaria in children and CSU in particular. We conducted a systematic review of articles published in English and French on pediatric CSU management in the last 10 years. We included experimental studies (eg, randomized controlled trials), other experimental designs (eg, nonrandomized methods of assignment, controlled before-after studies, and interrupted time series), and observational studies (eg, prospective or retrospective cohort studies, cross-sectional studies, case-control studies, and case reports). Our findings highlight the efficacy of second-generation antihistamines for the treatment of CSU in children and supports the use of omalizumab for more severe cases. However, our study also reveals severe knowledge gaps related to the best management strategy in children with more severe/refractory cases of CSU. Future studies are required to establish the beneficial effect of high doses of second-generation antihistamines as well as the effectiveness and safety of omalizumab and other biologics in young children.

Current Knowledge and Management of Hypersensitivity to Aspirin and NSAIDs

Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) are some of the most common culprits of drug-induced hypersensitivity reactions, and can lead to a wide array of adverse effects. The accurate and timely diagnosis of aspirin and NSAID-induced hypersensitivity reactions is important for both patient safety and for the initiation of appropriate disease-specific management and treatment. Because there are no reliably validated in vitro tests available, aspirin and NSAID challenges are considered to be the criterion standard for the diagnosis of these hypersensitivity reactions, though in some patients the diagnosis can be made on the basis of a clear clinical history.

Pro and Contra: Provocation Tests in Drug Hypersensitivity

Drug provocation test (DPT) is the controlled administration of a drug to diagnose immune- or non-immune-mediated drug hypersensitivity and the last step for accurate recognition of drug hypersensitivity reactions when the previous diagnostic evaluations are negative or unavailable. A DPT is performed only if other conventional tests fail to yield conclusive results. In each clinical presentation, "to provoke or not to provoke" a patient should be decided after careful assessment of the risk-benefit ratio. Well-defined benefits of DPT include confirmative exclusion of diagnoses of drug hypersensitivity and provision of safe alternatives. However, disadvantages such as safety, difficulty in interpretations of results, lack of objective biomarkers, risks of resensitization, efficiency in daily practice, and lack of standardized protocols, are poorly debated. This review summarizes the current published research concerning DPT, with particular emphasis on the advantages and disadvantages of DPT in an evidence-based manner.

Controversies and challenges in the management of chronic urticaria

This supplement reports proceedings of the second international Global Urticaria Forum, which was held in Berlin, Germany in November 2015. Despite the clear international guideline, there remain a number of controversies and challenges in the management of patients with chronic urticaria (CU). As a result of major advancements in urticaria over the past 4 years, the current EAACI/GA(2) LEN/EDF/WAO urticaria guideline treatment algorithm requires updating. Case studies from patients with chronic spontaneous urticaria (CSU) [also called chronic idiopathic urticaria (CIU)], chronic inducible urticaria (CIndU) or diseases and syndromes related to CU are useful in describing and exploring challenges in disease management. Case studies of specific CSU patient populations such as children with CU or patients with angio-edema but no hives also require consideration as potentially challenging groups with unmet needs. The current EAACI/GA(2) LEN/EDF/WAO urticaria guideline provides a general framework for the management of patients with CU but, as these cases highlight, a personalized approach based on the expert knowledge of the physician may be required.

Approaches to the diagnosis and management of chronic urticaria in children

Most guidelines for chronic urticaria (CU) in infants and children are based on limited pediatric evidence. Current evidence used to guide treatment in children is extrapolated from data focusing on older age groups. CU in children is a different and complex condition than that in adults. Furthermore, there is little published information regarding urticaria in Korean children. The aim of the present article is to review recent research on chronic childhood urticaria and improve the current understanding of its pathogenesis and management. The classification and definition of urticaria in adults also applies to children. CU is defined as a daily occurrence of spontaneous wheals, angioedema, or both for >6 weeks. The precise pathophysiology of CU is unknown and the rates of successful identification of a cause in children with CU vary from 20%-50%. There is no established laboratory test to evaluate the presence of urticaria. The natural course of childhood CU is undetermined, with limited reports discussing long-term outcomes. Second-generation H1 antihistamines are the cornerstone of management, while limited therapeutic drugs are available for adults.