The lifetime prevalence of urticaria, a severe allergic disease, is almost 20%. It not only limits the quality of life of those affected, but also their general performance at work and in their daily activities. This publication is the first section of the Urticaria Guideline. It covers the classification and diagnosis of urticaria, taking into account the major advances in research into its causes, triggering factors and pathomechanisms. It also addresses strategies for the efficient diagnosis of the different subtypes of urticaria. This is crucial for individual, patient-oriented treatment, which is covered in the second part of the guideline, published separately. This German-language guideline was developed according to the criteria of the AWMF on the basis of the international English-language S3 guideline with special consideration of health system characteristics in the German-speaking countries. This first part of the guideline describes the classification of urticaria, distinguishing spontaneously occurring wheals (hives) and angioedema from forms of urticaria with inducible symptoms. Urticaria is defined as sudden onset of wheals, angioedema, or both, but is to be distinguished from conditions in which wheals occur as a short-term symptom, such as anaphylaxis. The diagnosis is based on (a limited number of) laboratory tests, but especially on medical history. In addition, validated instruments are available to measure the severity, activity and course of the disease.

Urticaria is one of the most frequent dermatological diseases and it usually occurs in paroxysmal, recurrent form [...].

Urticaria is a disease triggered by mast cells and characterized by recurrent symptoms such as wheals and/or angioedema. Most patients benefit from treatment with antihistamines (AH) or, if not effective enough, from additional therapy with omalizumab, which leads to significant symptom relief. Here we present a patient with therapy-resistant chronic spontaneous urticaria treated with AH, omalizumab, and glucocorticosteroids. The subsequent recommended therapy according to the current guideline, cyclosporine A, was contraindicated in this patient. Therefore, therapy with dupilumab was initiated, resulting in a complete control of symptoms. In this case report, we present a case of successful dual therapy with omalizumab and dupilumab.

A 65-year-old African American man initially presented to the emergency department complaining of headaches, retro-orbital pressure, decreased vision, white flashes and floaters, and palinopsia of both eyes. After complete evaluation, he was diagnosed with migraine with aura and discharged to home with an ophthalmology follow-up. Upon follow-up with the ophthalmology team, he had developed severe periorbital inflammation, proptosis, chemosis, and vision loss that was greatest on the left side. The patient was immediately hospitalized for further evaluation and steroid treatment. His vision, ocular symptoms, and physical findings dramatically and rapidly improved with a 3-day course of high-dose intravenous steroids. Existing literature is sparse on rapid loss and recovery of vision following steroid treatment for orbital myositis. The exact mechanism of vision loss in orbital myositis is not understood and merits further investigation. Orbital myositis is a subset of nonspecific orbital inflammatory syndrome. It remains a poorly understood condition that mimics other, more common conditions such as thyroid eye disease and orbital cellulitis. If left untreated, orbital myositis could progress to the point of continued inflammation, enlargement of ocular tissues, ocular ischemia, and optic neuritis. To reverse these symptoms and prevent further progression, a quick diagnosis followed by steroid treatment is imperative.

Chronic spontaneous urticaria (CSU) is primarily a T2-dominant disease with a complex genetic background. Skin mast cell activation can be induced not only via the IgE-FcεRI axis but also from several other distinct mechanisms, molecules, and receptors involved in CSU onset, persistence, and exacerbation. These include autoallergy, autoimmunity, central or peripheral neuroimmune dysregulation, activation of both extrinsic and intrinsic coagulation pathways, and microbial infections. Besides mast cells, recent reports suggest the active and direct involvement of basophils and eosinophils. Several biological characteristics or biomarkers have been linked with CSU's known endotypes and may help forecast therapeutic responses. The introduction of biologic therapy for CSU has been a major advance in the last 10 years. The cornerstone of angioedema (AE) pathogenesis is increased vascular permeability and plasma leakage into the deeper dermis and subcutis, either mediated by histamine or bradykinin (BK). C1-inhibitor deficiency, hereditary or acquired, is the primary cause of BK-mediated AE due to increased plasma BK concentration. Other complex conditions have been identified, with some likely involving contact system dysregulation and other putative mechanisms related to vascular endothelial dysfunction. The approval of multiple hereditary-AE-specific therapies for both prevention and acute attacks has revolutionized treatment of this disease. Any new knowledge of the pathogenesis of CSU and AE offers the opportunity to improve patient information, physician-patient communication, prediction of therapeutic responses, selection of precise tailor-made treatment for each patient, and exploration of novel treatment options for those who do not achieve disease control with current medications.

Chronic urticaria is a dermatological condition characterized by the appearance of wheals or angioedema longer than 6 weeks. It could cause serious complications such as laryngeal edema, vasculitis, and diarrhea. However, the pathologic changes of the ocular fundus caused by chronic urticaria are rarely reported. In this study, we described the pathologic changes of ocular fundus in a patient with history of chronic urticaria and central serous chorioretinopathy. A 28-year-old female was presented with blurred vision and distorted images in her right eye for 6 days. The patient was diagnosed with choroidal neovascularization. She received an intravitreal injection of conbercept (0.5 mg/eye/time) monthly. Finally, no abnormality was found in her ocular examination after 4 months of first injection. In conclusion, chronic urticaria could cause central serous chorioretinopathy, leading to choroidal neovascularization. Intravitreal conbercept injection showed an excellent local therapeutic efficacy for this eye condition.

Acute angioedema is mostly found in the head and neck region. Therefore, it can be life threatening by potentially endangering air way patency. Pathophysiologically angioedemas can be divided into mast cell-mediated or bradykinin-mediated forms. Differentiation is essential due to the different therapeutic strategies. In cases of doubt, initial therapy with adrenalin, antihistamines, and glucocorticoids should be initiated. This initial emergency treatment is comparable to the treatment of allergic reactions. For diagnosed or suspected hereditary angioedema, specific treatments are available. For drug-associated forms, immediate and life-long cessation of the medication is crucial. In the emergency situation, diagnosis can only be based on medical history and clinical symptoms. Recognition of impending airway obstruction and securing the airway is of highest priority; final diagnosis must be confirmed later.

Chronic urticaria is a debilitating skin condition that is defined as itchy hives at least twice a week and lasting for six or more weeks, with or without angioedema. Chronic spontaneous urticaria (CSU) is a form of disease that is witnessed in two-thirds of those with chronic urticaria. This meta-analysis explores the efficacy of differential dosages of omalizumab for outcomes of weekly itching scores, weekly wheal scores, urticarial assessment score 7 (UAS7), and responder rates. Adhering to PRISMA Statement 2020 guidelines, a systematic search of PubMed/MEDLINE, Scopus, Embase, and Web of Science was conducted until 15 September 2022. A combination of the following keywords was used: omalizumab and chronic urticaria. Data comprising clinical trial ID, name, author/year, country, dosage and time of intervention, inclusion criteria, mean age, female gender, and racial grouping information were obtained. The meta-analytical outcomes were analyzed in RevMan 5.4. The risk-of-bias assessment was conducted using version 2 of the Cochrane risk-of-bias tool for randomized trials (RoB 2). A total of 10 trials comprising 1705 patients with CSU were included. Notably, 1162 belonged to the intervention group, while 543 were controls. A total of 70.4% of the participants were female in the intervention group, while 65.6% of them were female in the control group. The overall mean age was 38.64 ± 10.66 years. Weekly itch score outcomes were most notable with 150 mg dosage (Cohen's d = -2.6, 95% CI = -4.75, -0.46, p = 0.02). The weekly wheal score outcomes had the largest effect size with 300 mg dosage (Cohen's d = -1.45, 95% CI = -2.2, -0.69, p = 0.0002). For UAS7 outcomes, the largest effect size was yielded with 150 mg dosage (Cohen's d = -6.92, 95% CI: -10.38, -3.47, p < 0.0001). The response rate to omalizumab had a likelihood of being higher with 300 mg of intervention compared to placebo (OR = 8.65, 95% CI = 4.42, 16.93, p < 0.0001). Well-rounded urticarial symptom resolution was observed with 150 mg and 300 mg dosages of omalizumab. Improvement of UAS7 was more comparable with 150 mg dosage, whereas the chance of response to treatment was higher with 300 mg dosage. Our findings support omalizumab as an effective intervention for adult and pediatric populations that are resistant to many therapies, including high-dose H1-antihistamines.

Drug hypersensitivity reactions (DHRs) are a type of adverse drug reactions with heterogeneous pathophysiological mechanisms and a broad spectrum of clinical manifestations. Since over-diagnosing is common in children, a complete allergy work-up is needed. A cross-sectional study was conducted at a tertiary care institution, covering the five-year period. Five hundred and four patients of both sexes, mean age 7.5 and with a medical history suggestive of DHR were evaluated. ENDA/EAACI guidelines were used for a diagnostic algorithm. Single drug hypersensitivity was registered in 375 patients and multiple drug hypersensitivity in 129. The main culprits in medical history were antibiotics (83%), non-steroidal anti-inflammatory drugs (NSAIDs) (8.4%) and analgoantipyretics (3.8%). Skin involvement was registered in 96.2%. DHRs were confirmed in 4.4% patients-six patients had positive skin tests and 13 had a positive drug provocation test. In the proven DHRs group, the main agents were antibiotics (72.7%), followed by NSAIDs (8.3%), and of all the skin manifestations, urticaria was most common (78.2%), followed by exanthema (10.5%) and angioedema (5.3%). Considering the above, anticipating DHRs and a proper referral of children to an allergologist is a key step in the assessment of drug hypersensitivity. A complete allergy work-up prevents unnecessary drug exclusion and allows most children to safely continue the use of first-line medications when needed.

Oral drug provocation tests (DPT) are the basic diagnostic tool for the detection of hypersensitivity to non-opioid analgesics and for selecting a safe alternative for a patient. They are of great practical importance due to their common use, but the data on the follow-up of patients after negative DPT are still very scarce. We examined the further fate of 164 such adult patients after negative NSAID or paracetamol tests and analyzed which excipients in the studied drugs they could be exposed to after the diagnostic workup. A structured medical interview was performed 32.9 months (mean) after the provocation tests. Of the 164 patients, 131 (79.9%) retook the tested drug and 12 developed another hypersensitivity reaction, giving the estimated negative predictive value of 90.8%. These reactions were induced by acetylsalicylic acid, paracetamol, meloxicam, and diclofenac, and were clinically similar to the initial ones (most commonly urticaria and angioedema). There are 93 generics of these drugs on the local market, containing a total of 33 excipients for which hypersensitivity reactions have been reported. All available generics contain such excipients. Thirty-one patients (20.1%) did not take the previously tested drug again, most often because it was not needed or because they were afraid of another reaction. DPT with analgesics has a high diagnostic performance. A minority of patients had relapsed after reexposure. One of the underestimated reasons for this may be drug excipients provoking a reaction, so it is advisable to use exactly the same medical product that has been negatively tested. Many patients avoid reexposure to a given drug, despite negative tests, therefore very reliable patient education in connection with DPT is highly needed.

Although favipiravir is a promising drug for coronavirus disease 2019, some adverse effects, including skin lesions, have been reported. A 56-year-old female who was prescribed favipiravir by a filiation team following a positive severe acute respiratory syndrome coronavirus 2 polymerase chain reaction test presented to our hospital. After examination, favipiravir and paracetamol were prescribed. She represented to the hospital with facial swelling and itchy rashes on her forearm. Angioedema and urticaria were diagnosed. Favipiravir was discontinued. Steroid and antihistaminic therapy were administered for angioedema. To our knowledge, this is the first reported case of favipiravir-induced angioedema and urticaria in Turkey.

Management of psychiatric disorders in high-risk cardiac patients often requires difficult decision making when it comes to acceptable medication side effects. We present the case report of a 28-year-old female with a history of generalized anxiety disorder (GAD), major depressive disorder (MDD), intravenous heroin use disorder, and prior tricuspid valve replacement who presented to the hospital with signs and symptoms of sepsis. She was found to have corrected QT interval (QTc) prolongation and infective endocarditis with blood cultures positive for Streptococcus viridans. Due to QTc prolongation, her home medication of citalopram was discontinued in favor of escitalopram. Within 24 hours of administration, the patient experienced angioedema with periorbital swelling, lip swelling, and urticaria of the face and arms which was resolved with intravenous (IV) diphenhydramine. In this case report, we present what we believe to be the first recorded case of escitalopram-induced angioedema in a patient without a past medical history of hereditary angioedema (HAE), and how pharmacogenomic testing influenced antidepressant medication selection.