Pediatric chronic spontaneous urticaria: a brief clinician's guide.

INTRODUCTION: Chronic urticaria (CU) appears with daily or intermittent/recurrent wheals with/without angioedema for more than six weeks. When no specific eliciting factors are found, chronic urticaria is defined as spontaneous (CSU). Up to 50% of patients with CSU do not respond to therapy, leading to a prolonged disease course and the need for expensive therapies, impacting the quality of life (QoL) and healthcare resources. AREAS COVERED: Diagnosis of CSU is made when other potential causes of chronic urticaria are excluded. CSU therapy aims to achieve complete control of symptoms and normalization of QoL. Current treatment options for urticaria aim to target mast cell mediators such as histamine, or activators, such as autoantibodies. Guidelines recommend starting with second generation antihistamines (sgAHs) and adding omalizumab therapy if symptoms are not controlled. This review aims to provide a practical guide for CSU in the pediatric population. EXPERT OPINION: Treatment options for pediatric CSU are primarily based on adult data that have been extrapolated for children. Current guidelines should be reevaluated based on pediatric data, new biological treatments, and the COVID-19 pandemic. Future research is needed to investigate strategies to personalize current treatments and identify potential predictive biomarkers.

Liver-spleen axis dysfunction in COVID-19.

Coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an acute infectious disease that spreads mainly through the respiratory route. Besides interstitial pneumonia, a number of other clinical manifestations were noticed in COVID-19 patients. In particular, liver and spleen dysfunctions have been described both as complications of COVID-19 and as potential predisposing factors for severe COVID-19. Liver damage is rather common in COVID-19 patients, and it is most likely multifactorial, caused by the direct insult of SARS-CoV-2 to the liver by the cytokine storm triggered by the virus, by the use of hepatotoxic drugs, and as a consequence of hypoxia. Although generally mild, liver impairment has been found to be associated with a higher rate of intensive care unit admission. A higher mortality rate was reported among chronic liver disease patients. Instead, spleen impairment in patients with COVID-19 has been poorly described. The main anatomical changes are the architectural derangement of the B cell compartment, white pulp atrophy, and reduction or absence of lymphoid follicles, while, from a functional point of view, the IgM memory B cell pool is markedly depleted. The outcome of COVID-19 in asplenic or hyposplenic patients is yet to be defined. In this review, we will summarise the current knowledge regarding the impact of SARS-CoV-2 on the liver and spleen function, as well as the outcome of patients with a pre-existent liver disease or defective spleen function.

Autoimmune diseases associated with common variable immune deficiency.

Common variable immunodeficiency (CVID) is the most prevalent primary immune deficiency, affecting roughly 2-4/100 000 individuals in the general population. The etiology is currently unknown, even if several genetic mutations have been described, and no single clinical feature or single laboratory test can establish the diagnosis, which is based on multiple criteria. CVID is characterized by B- and T-cell dysfunction that predisposes to an increased risk of infections, with the typical involvement of the respiratory and gastrointestinal tracts. Besides this well-established complication, though the coexistence of immunodeficiency and autoimmunity appears paradoxical, two-thirds of CVID patients present concomitant autoimmune disorders. Of note, autoimmunity can often be the only clinical manifestation of CVID at the time of diagnosis. The most common autoimmune disorders associated with CVID are autoimmune cytopenias, that is, immune thrombocytopenic purpura and autoimmune hemolytic anemia, either as separate entities or as concurrently (Evans syndrome). CVID patients can also manifest rheumatologic diseases (eg, arthritis, Sjogren's disease, systemic lupus erythematosus, vasculitis, Behçet's syndrome) and gastrointestinal autoimmune disorders (eg, ulcerative colitis, autoimmune atrophic gastritis, celiac disease). This latter may pose a particular diagnostic challenge, as celiac-specific autoantibodies can be absent in CVID patients. Understanding the molecular basis and the clinical impact of autoimmunity in CVID patients might help manage CVID, thus reducing its diagnostic delay and preventing its complications.