Labial angioedema in an elderly woman with hypogammaglobulinemia, grass allergy and urticaria: a case report

This is the clinical case of an elderly woman with stabilized polypathology, suffering from a grass allergy, multiple intolerances, episodes of urticaria, and recurrent labial angioedema. The diagnostic work-up, carried out over many years, failed to yield definitive conclusions, as increases in eosinophils, elevated immunoglobulin (Ig) E, and autoimmune phenomena were all ruled out. Only in later life was a mild hypogammaglobulinemia discovered, specifically an IgG2 subclass deficiency. According to the recent DANCE classification, the labial angioedema was interpreted as idiopathic histaminergic angioedema, which was also suggested by the fact that, after initiating long-term therapy with a second-generation antihistamine, the clinical manifestations did not recur. Although we investigated possible links between chronic urticaria, angioedema, and hypogammaglobulinemia, the case remains partially unresolved, as reports of IgG subclass deficiency associated with angioedema are extremely rare. Only targeted genetic analyses could better define this inborn error of immunity, especially considering that hypogammaglobulinemia was also found in a family member.