Demographic and clinical profiles in patients with acute urticaria

Immunopathogenesis of urticaria: a clinical perspective on histamine and cytokine involvement

BACKGROUND

Urticaria is a clinical condition characterized by the appearance of wheals (hives), angioedema, or both. Over the last several decades, a better understanding of the mechanisms at play in the immunopathogenesis of urticaria has underscored the existence of numerous urticaria subtypes. Separating the different kinds of urticaria explicitly helps find the best detection method for the management of this skin disorder. Subtypes of urticaria also include both spontaneous and physical types. The conventional ones include spontaneous urticaria, constituting both acute and chronic urticaria. Therefore, a broad and effective therapy is essential for the diagnosis and treatment of urticaria.

METHODS

To understand the immunopathogenesis of urticaria, various databases, including PubMed, Scopus, and Web of Science, were used to retrieve original articles and reviews related to urticaria. While information on several clinical trials were obtained from clinicaltrials.gov database.

RESULTS

This article highlights the immunopathogenesis involved in the intricate interaction between cellular infiltration, immune reactions, coagulation cascades, and autoantibodies that underlie urticaria's pathophysiology.

CONCLUSION

The recent progress in understanding urticaria can help to understand the intricate characteristics in the immunopathogenesis of urticaria and could play a beneficial role in the management of urticaria.

Etiological causes in patients with acute urticaria and angioedema: A cross-sectional study

BACKGROUND

Acute urticaria and angioedema are emergency dermatological conditions associated with various etiologic factors.

OBJECTIVE

To determine the etiological causes in patients with acute urticaria and angioedema, and to investigate whether more than one etiological cause was present, along with the patients' laboratory values.

METHODS

The study was conducted in a tertiary hospital with one center. Etiological causes and laboratory parameters in 284 patients diagnosed with acute urticaria and angioedema were retrospectively studied.

RESULTS

A total of 284 patients were included in the study. The mean age of the patients was 42.7 ± 15.6 years, where 163 (57.4%) were women and 121 (42.6%) were men. Acute urticaria and angioedema occurred together in 149 (52.5%) patients. At least one precipitating factor among the predisposing risk factors was present in 220 (77.5%) patients, and more than one precipitating factor was found in 51 (18%) patients. Medication use was found in 157 (55.3%) patients and infection in 54 (19%). The development of urticaria after food consumption was noted in nine (3.2%) individuals. A history of infection and medication intake was present in 50 (17.6%) patients. A joint history of food consumption and medication intake was present in only one patient. Elevated C-reactive protein level was found in 178 (62.7%) patients and elevated anti-streptolysin O titer in 41 (14.4%) patients. Vitamin B12 deficiency was found in 116 (40.8%) patients and vitamin D deficiency in 254 (89.4%).

CONCLUSION

Acute urticaria and angioedema may occur as a result of multiple etiological factors, in which different triggers may be present simultaneously.

Clinical review: The suggested management pathway for urticaria in primary care

Background

Urticaria is a common condition presenting both as acute and chronic disease within primary care. To those without specialist training it is poorly understood from the points of view of diagnosis and management. It causes a considerable disease burden to sufferers with marked impact on quality of life.

Purpose of this review

The recent publication of the EAACI/GA²LEN/EuroGuiDerm/APAAACI Guideline for the Definition, Classification, Diagnosis and Management of Urticaria guideline prompted us to take this excellent resource and re-configure its findings and recommendations to a non-specialist audience with particular reference to the needs of the primary care team.

Urticaria

Urticaria is an inflammatory skin disorder that affects up to 20% of the world population at some point during their life. It presents with wheals, angioedema or both due to activation and degranulation of skin mast cells and the release of histamine and other mediators. Most cases of urticaria are acute urticaria, which lasts ≤6 weeks and can be associated with infections or intake of drugs or foods. Chronic urticaria (CU) is either spontaneous or inducible, lasts >6 weeks and persists for >1 year in most patients. CU greatly affects patient quality of life, and is linked to psychiatric comorbidities and high healthcare costs. In contrast to chronic spontaneous urticaria (CSU), chronic inducible urticaria (CIndU) has definite and subtype-specific triggers that induce signs and symptoms. The pathogenesis of CSU consists of several interlinked events involving autoantibodies, complement and coagulation. The diagnosis of urticaria is clinical, but several tests can be performed to exclude differential diagnoses and identify underlying causes in CSU or triggers in CIndU. Current urticaria treatment aims at complete response, with a stepwise approach using second-generation H1 antihistamines, omalizumab and cyclosporine. Novel treatment approaches centre on targeting mediators, signalling pathways and receptors of mast cells and other immune cells. Further research should focus on defining disease endotypes and their biomarkers, identifying new treatment targets and developing improved therapies.

Acute Urticaria and Anaphylaxis: Differences and Similarities in Clinical Management

Acute urticaria is a common condition that presents with wheals and/or angioedema. However, these symptoms are also frequent in anaphylaxis, a life-threatening reaction that should be immediately diagnosed and treated. In both, mast cells play a central role in the physiopathology. Causes and triggers of acute urticaria and anaphylaxis are similar in general, but some peculiarities can be observed. The diagnostic approach may differ, accordingly to the condition, suspicious causes, age groups and regions. Adrenaline is the first-line treatment for anaphylaxis, but not for acute urticaria, where H1-antihistamines are the first choice. In this paper, we review the main aspects, similarities and differences regarding definitions, mechanisms, causes, diagnosis and treatment of acute urticaria and anaphylaxis.

Risk Factors for Acute Urticaria in Central California

At least 15–20% of the population in the world suffers from urticaria. Allergy triggers contribute to the development of urticaria. Not much is known about the demographic and environmental risk factors that contribute to the occurrence of acute urticaria. Methods: We utilized emergency department data on acute urticaria-related visits managed by the California Office of Statewide Planning and Operations for 201 zip codes located in southern central California (San Joaquin Valley) collected during the years 2016 and 2017. Census data from the same zip codes were considered as a population at risk. Socioeconomic and environmental parameters using CalEnviroScreen (Office of Environmental Health Hazard Assessment, Sacramento, CA, USA) database for the zip codes were evaluated as risk factors. Results: The incidence rate of acute urticaria in San Joaquin Valley during 2016–2017 was 1.56/1000 persons (n = 14,417 cases). Multivariate Poisson analysis revealed that zip codes with high population density (RR = 2.81), high percentage of farm workers (RR = 1.49), and the composite of those with high and medium percentage of poverty and those with high and medium percentage of non-white residents (RR = 1.59) increased the likelihood of the occurrence of acute urticaria. Conclusion: High population density, farm work, poverty and minority status is associated with a high risk of having acute urticaria.

Etiological and predictive factors of pediatric urticaria in an emergency context

Background

Urticaria is common in pediatric population and is caused by various etiologies which usually differ among different age groups. The different etiologies require different management strategies. Thus, understanding detailed of the etiologies of urticaria in children would help pediatricians to perform appropriate initial treatment.

Methods

A cross-sectional epidemiological study of all patients aged under 18-year-old with the diagnosis of urticaria from any causes entered in the emergency department during January 1st, 2016 to December 31st, 2019 by collecting the data from the Health Object Program®, an authorized electronic medical records program, at the Srinagarind Hospital, Faculty of Medicine, Khon Kaen University, Thailand.

Results

There were total of 515 urticaria patients aged under 18 years old at the emergency department. The ages of patients ranged from 8 months to 18 years with a median age of 7 years (IQR 3.17–12.08). The majority of the patients were in the preschool-aged group (40.97%), followed by the school-aged (28.16%), adolescent (22.14%), and infant (8.74%). Six major etiologic categories were identified in the present study. The most common cause of urticaria was infection (51.26%), followed by idiopathic urticaria (34.37%), inhalants (6.99%), drugs (4.08%), foods (2.52%), and insect stings (0.78%).

Conclusions

Having underlying allergic diseases had a strong association with all identified causes of urticaria in the study population, of which, food and inhalation etiologies had a significant difference when compared to the other identified causes. The present study has found that infection was the most common cause of acute urticaria in children. This etiology (infection-induced urticaria) usually presents concurrent with fever, however, non-febrile symptoms were also presented. Therefore, in the pediatric population, pediatricians should always look for infection as the cause of urticaria even in patients without pyrexia.

Urticaria: recommendations from the Italian Society of Allergology, Asthma and Clinical Immunology and the Italian Society of Allergological, Occupational and Environmental Dermatology

BACKGROUND

Urticaria is a disorder affecting skin and mucosal tissues characterized by the occurrence of wheals, angioedema or both, the latter defining the urticaria-angioedema syndrome. It is estimated that 12-22% of the general population has suffered at least one subtype of urticaria during life, but only a small percentage (estimated at 7.6-16%) has acute urticaria, because it is usually self-limited and resolves spontaneously without requiring medical attention. This makes likely that its incidence is underestimated. The epidemiological data currently available on chronic urticaria in many cases are deeply discordant and not univocal, but a recent Italian study, based on the consultation of a national registry, reports a prevalence of chronic spontaneous urticaria of 0.02% to 0.4% and an incidence of 0.1-1.5 cases/1000 inhabitants/year.

METHODS

We reviewed the recent international guidelines about urticaria and we described a methodologic approach based on classification, pathophysiology, impact on quality of life, diagnosis and prognosis, differential diagnosis and management of all the types of urticaria.

CONCLUSIONS

The aim of the present document from the Italian Society of Allergology, Asthma and Clinical Immunology (SIAAIC) and the Italian Society of Allergological, Occupational and Environmental Dermatology (SIDAPA) is to provide updated information to all physicians involved in diagnosis and management of urticaria and angioedema.

Topography of itch: evidence of distinct coding for pruriception in the trigeminal nerve

Introduction

Little is known about the topographical distribution of pruriception (in particular for nonhistaminergic itch), although conditions with chronic itch frequently occur in distinct anatomic and often bilateral patterns. This study aimed to investigate regional differences in the sensitivity to itch stimuli by assessing the intensity of itch, pain, and cutaneous neurogenic flare evoked by histamine and cowhage in different anatomic regions in 20 healthy volunteers.

Methods

Itch was induced by 1% histamine applied with a prick lancet or by insertion of 25±5 cowhage spicules in 4 regions: volar/dorsal forearm, lower back, and chin. The duration and intensity of itch and pain following each pruritic stimulus were measured by a continuous visual analogue scale (VAS_0-100). Sensitivity to touch-evoked itch was assessed by von Frey filaments and cutaneous flare was quantified by full-field laser perfusion imaging.

Results

Peak itch intensity was lower at the chin (19.4±3.6) compared with other areas (mean of 3 locations; 41.3±4.4), independently of whether histamine or cowhage was applied (P<0.01). Baseline sensitivity to touch-evoked itch was higher on the chin (P<0.01), but here hyperknesis did not develop in contrast to other areas (P<0.05). Cutaneous flare was more intense but had a smaller dispersion at the chin, compared with other areas (P<0.01).

Discussion

In conclusion, sensitivity to histaminergic and non-histaminergic itch diverges considerably between body regions. Lower density of pruriceptive CMH and CMI-neurons or distinct neuronal substrates for itch in the mandibular part of the trigeminal area may explain the observed reduced itch and vasomotor responses.

Anaphylaxis in a 4-year-old male caused by contact with grasses: a case report

Background

Acute urticaria is the presence of urticaria for <6 weeks, and it is the most common type of urticaria in children. Sometimes, it may be associated with anaphylaxis, a life-threatening condition. Urticaria must be differentiated from anaphylaxis because the latter may require emergency treatment. We describe a child with anaphylaxis exposed to grasses on two occasions.

Case presentation

We described a 4-year-old male child with anaphylaxis exposed to grasses. Patient also suffered mild neurologic/respiratory symptoms but it is unlikely that he had anaphylaxis. Skin-prick tests were positive to Cynodon dactylis, Phalaris arundinacea and Festuca elatior. Little is known about the importance of pollens as a cause of urticaria in young children.

Conclusions

The case reported here is particularly interesting because, to the best of our knowledge, anaphylaxis due to pollen exposure in children aged <4 years has not been reported before. We strongly encourage all physicians searching for the cause of acute urticaria (allergists, dermatologists, primary-care physicians) to consider the possibility of pollen allergy, and to screen these patients for pollen sensitization.

Particularities of allergy in the Tropics

Allergic diseases are distributed worldwide and their risk factors and triggers vary according to geographical and socioeconomic conditions. Allergies are frequent in the Tropics but aspects of their prevalence, natural history, risk factors, sensitizers and triggers are not well defined and some are expected to be different from those in temperate zone countries. The aim of this review is to investigate if allergic diseases in the Tropics have particularities that deserve special attention for research and clinical practice. Such information will help to form a better understanding of the pathogenesis, diagnosis and management of allergic diseases in the Tropics. As expected, we found particularities in the Tropics that merit further study because they strongly affect the natural history of common allergic diseases; most of them related to climate conditions that favor permanent exposure to mite allergens, helminth infections and stinging insects. In addition, we detected several unmet needs in important areas which should be investigated and solved by collaborative efforts led by the emergent research groups on allergy from tropical countries.