Urticária aquagênica familiar: relato de dois casos e revisão da literatura

A Systematic Review of Aquagenic Urticaria-Subgroups and Treatment Options

BACKGROUND

Aquagenic urticaria (AquaU) is a rare variant of chronic inducible urticaria where wheals occur after skin contact with water. Information on clinical manifestations and treatment outcomes is limited, which makes the management of AquaU challenging.

OBJECTIVE

To systematically review disease features and relevant triggers of AquaU and patients' response to treatment.

METHODS

Related articles were searched by use of the terms "aquagenic urticaria" and "aquagenic angioedema" until June 2021 and reviewed according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis recommendations.

RESULTS

A total of 77 patients with AquaU were investigated in 59 studies including 47 case reports and 12 case series. AquaU predominantly presented in women (47 patients, 61%), and the mean age of onset of the disease was 19.6 ± 10.8 years (range: 0-54 years). Wheals commonly occurred in localized areas and regardless of the water temperature. Based on the reviewed evidence, AquaU can be classified as familial AquaU (FAquaU, 18.2%) and acquired AquaU (AAquaU, 81.8%). Although many treatments were used in both subtypes of AquaU, the use of second-generation H₁ antihistamines (2^ndAH₁) was reported most often to achieve marked improvement in both subtypes. The use of topical therapies in AquaU, which most commonly use hydrophobic vehicles, is poorly documented and of controversial efficiency.

CONCLUSIONS

AquaU is proposed to be classified into 2 subtypes, FAquaU and the more common AAquaU. Treatment with a 2^ndAH₁ is recommended as the first-line treatment for both types of AquaU. Further studies are required to fill knowledge gaps.

Aquagenic urticaria: Water, friend, or foe?

There are <100 reported cases of aquagenic urticaria. Although most are sporadic, several diseases have been associated. Diagnosis is based on provocation tests. Second-generation antihistamines are the first-line treatment.

Chronic Urticaria in Children: an Update on Diagnosis and Treatment

PURPOSE OF REVIEW

Both adults and children are frequently affected by symptoms of itchy urticarial lesions that cause considerable distress and impact nearly all their daily activities. A comprehensive history is critical to identify the etiology in patients who have chronic spontaneous urticaria (CSU) (those with symptoms for > 6 weeks) and is more important than extensive laboratory serum tests. Unfortunately, most of the current treatment guidelines have been based on data from adult studies since there is rare data on children. These treatment algorithms have been subsequently used to extrapolate treatments for children.

RECENT FINDINGS

Current treatment regiments do not achieve complete success in all patients, neither adults nor children. As the pathophysiology of chronic urticaria slowly becomes defined, novel therapies are being tested which target these individual molecular pathways to treat those that continue to experience symptoms. Future studies are required to establish the natural history, risks/benefits and efficacy of current medications, and biologics used to treat CSU in children.

Review of Physical Urticarias and Testing Methods

PURPOSE OF REVIEW

This review aims to update the information available on the prevalence, clinical picture, diagnostic methods, and treatment of urticarias induced by external physical stimuli.

RECENT FINDINGS

Physical urticarias are present in up to 5% of the general population, and in 10 to 50% of patients with chronic urticaria. Recent investigations have provided evidence that the presence of physical urticaria alone or when comorbid with chronic spontaneous urticaria is associated with a worse prognosis and duration. Most frequent subtypes of physical urticaria are dermographism and delayed pressure urticaria. The diagnosis is established through specific provocation tests and the management encompasses avoidance measures, pharmacologic therapy with nonsedating antihistamines, and alternative medications in refractory cases.

Aquagenic Urticaria Diagnosed by the Water Provocation Test and the Results of Histopathologic Examination

An 18-year-old male visited our department complaining of recurrent episodes of an itchy rash after hand washing, showering/bathing, drinking water, and getting rain-soaked. He was diagnosed with aquagenic urticaria after a water provocation test and histopathologic examination. Five months of antihistamine treatment successfully prevented further wheal formation. Aquagenic urticaria is a very unusual form of physical urticaria caused by contact with water. It manifests as pruritic small wheals surrounded by erythema within 30 minutes of exposure. The condition can be diagnosed by a water provocation test. Systemic antihistamines are the first-line treatment, with anticholinergics, phototherapy, or barrier cream used alternatively or additionally. Four cases of aquagenic urticaria have been reported in Korea, but no histopathologic evaluation was reported in the English or Korean literature. Herein, we provide both a case report of aquagenic urticaria diagnosed by the water provocation test and histopathologic examination results for this patient.

The definition, diagnostic testing, and management of chronic inducible urticarias - The EAACI/GA(2) LEN/EDF/UNEV consensus recommendations 2016 update and revision

These recommendations for the definition, diagnosis and management of chronic inducible urticaria (CIndU) extend, revise and update our previous consensus report on physical urticarias and cholinergic urticaria (Allergy, 2009). The aim of these recommendations is to improve the diagnosis and management of patients with CIndU. Our recommendations acknowledge the latest changes in our understanding of CIndU, and the available therapeutic options, as well as the development of novel diagnostic tools.

[Inducible urticaria and chronic spontaneous urticaria]

In the recently published 2013 revision of the guidelines of urticaria, chronic urticaria (CU) gathers chronic spontaneous urticaria (CSU) and inducible urticaria (IU), and excludes pseudourticarial rashes with more than 24h-lasting rash or more than 72h-lasting angiœdema. Activity and psychosocial impact of the disease must be measured with validated scores such as Urticaria and Angioedema Activity Scores, Urticaria Control Test, CU-Q2OL, AE-QOL. Although an allergic cause is generaly absent in CU, pathomecanisms remain elusive even since the well-known role of mast cell degranulation and the presence of autoantibodies anti-FcRεI or anti-IgE. Coagulation pathways may be involved, at least as an amplifying phenomenon. Mean duration of CU is 1 to 4 years, but many patients still have symptoms after 10 years, some predictive factors being known as severity, angioedema, a positive autologous serum test, inducible urticaria. Recommended routine diagnosic tests are validated provocation tests for IU (and cryoproteins for cold urticaria), blood cell count and CRP for CSU, since a thorough history and a normal detailed physical examination should avoid unnecessary tests. Management of CU has been improved by the off-label use of increased dosages of second generation anti- H1 antihistamines, but a subsequent therapeutic intensification may be necessary in some cases. Educational program may prevent this intensification. Independent studies evaluating available molecules are needed, along with more fundamental research studies.

Aquagenic urticaria in twins

We describe the case of 18 year old twin brothers who presented to our unit with a 3 year history of aquagenic urticaria. This rare form of urticaria usually presents within an hour of contact with water. The aetiology is unknown. Most cases are sporadic but there are a small number of familial cases in the medical literature. A specific genetic mutation has not yet been found. To our knowledge, this is the first report of aquagenic urticaria in monozygotic twins, further supporting a genetic component to this disease.