Confirming acetylsalicylic acid hypersensitivity as a cause of chronic urticaria by desensitization

A female aged 72, with diabetes type 2, hypertension, hypercholesterolemia, narrowing of the left internal carotid artery, suspected coronary heart disease, nodular thyroid disease with subclinical hyperthyroidism, and osteoarthritis, was admitted to the Allergology Department due to chronic urticaria. In anamnesis, urticaria and angioedema started about 40 years before. At the beginning there was a correlation between symptoms and usage of nonsteroidal anti-inflammatory drugs (NSAID) (e.g. ketoprofen). There were also cutaneous changes after local use of ointments with analgesic drugs. Since September 2016 urticaria has been constant, sometimes with concomitant angioedema of eyelids. The patient observed worsening of symptoms after spicy meals. No additional symptoms indicating systemic reaction, like hypotension, dyspnoea, wheezing, gastrointestinal or other organ involvement were present. Aspirin (ASA) provocation was not suitable in this patient since she presented with constant urticaria. Thus, the basophil activation test with acetylsalicylic acid (BAT-ASA) was performed but the result was undiagnostic (due to unspecific degranulation of basophils without any factor). In December 2016, the patient was admitted to the Department of Allergology due to continuous severe urticaria. The patient was then treated with antihistaminic drugs and systemic steroids with good results, however an oral provocation test with acetylsalicylic acid could not be performed then. BAT-ASA was again undiagnostic (again due to unspecific degranulation of basophils without any factor). Even though after discharge the patient continued antihistaminic medication, recurrence of urticaria was observed