Your browser doesn't support javascript.
Systemic reaction triggered by SARS-COV- 2 infection in a patient with chronic autoimmune urticaria
Allergy: European Journal of Allergy and Clinical Immunology ; 78(Supplement 111):321-322, 2023.
Article in English | EMBASE | ID: covidwho-2302756
ABSTRACT
Case report Chronic urticaria is defined as the presence of urticaria for a period exceeding six weeks. Infections are known as possible triggers for urticaria manifestations, and, as such, SARS-CoV- 2 infection can be recognized as causative. An 8-year- old boy, with a previous history of idiopathic chronic urticaria, came to the Emergency Department for the appearance of generalized urticaria and lips angioedema associated with vomit and shortening of breath normal vital signs by age. Thus, due to the significant reaction, intravenous corticosteroids and antihistamines were promptly administered, with a rapid improvement of symptoms. Since the systemic reaction, the tryptase dosage was performed with the identification of an elevation at the time of the arrival and a complete normalization after the twelfth hour from the beginning of the reaction. Figure 1 shows the kinetic of the tryptase over time. SARS-CoV2 swab was performed before hospitalization and a positive test was identified. To investigate the etiopathogenesis of reaction, the patient was submitted to the extensive clinical, laboratory, and instrumental investigations that revealed only a positive in vitro basophil activation test (BAT) as evidence of functional serum histamine-releasing autoantibodies that are directed against IgE or high-affinity IgE receptors. The viral infection did not need any medication, and the urticaria was resolute in a couple of days. Daily treatment with oral antihistamines was then prescribed, and no further urticarious episodes occurred. A negative SARS-CoV- 2 swab was detected within 12 days of beginning symptoms. Approximately 40% of patients with idiopathic chronic urticaria have circulating antibodies versus IgE epitopes or the IgE receptor, but as it occurs in many autoimmune conditions, the presence of autoantibodies does not necessarily result in a disease phenotype. It is demonstrated that infections can elicit an autoimmune condition, and as our report shows, SARS-CoV2 could explain the reaction observed in our patient. The autoimmune precondition could have been the primer of the systemic reaction, pre-activating the mastocyte degranulation, as the tryptase elevation demonstrated. On the other hand, the SARS-CoV2 virus reducing the ACE2 expression, due to virus endocytosis, could create an imbalance in the RAS system, increasing the bradykinin levels. Bystander activation of pre-activated mastocytes caused by an inflammatory environment could explain the systemic reaction described above.
Keywords

Full text: Available Collection: Databases of international organizations Database: EMBASE Language: English Journal: Allergy: European Journal of Allergy and Clinical Immunology Year: 2023 Document Type: Article

Similar

MEDLINE

...
LILACS

LIS


Full text: Available Collection: Databases of international organizations Database: EMBASE Language: English Journal: Allergy: European Journal of Allergy and Clinical Immunology Year: 2023 Document Type: Article