[De-sensitization to allopurinol in a patient with tophi gout].

Background: Allopurinol is a xanthine oxidase inhibitor used in the treatment of patients with gout. Approximately 2% of patients are affected by adverse reactions to this drug. Severity ranges from mild rashes to severe reactions in up to 0.

[Adverse effects with ambulatory intravenous immunoglobulin administration in adult patients with common variable immunodeficiency].

Background: Common variable immunodeficiency (CVID) is the most frequent symptomatic primary immunodeficiency, affecting 1:25,000-75,000 people. It is characterized by the absence or decrease antibody production. Treatment for CVID consists on human immunoglobulin administration, and the intravenous route is the most common route for administration, at 400-800 mg/kg of weight every 3-4 weeks.

[Oral allergy syndrome in adults of a third level hospital].

Background: Oral allergy syndrome (OAS) is the mildest form of an allergic reaction to foods. It is characterized by the presence of IgE mediated symptoms restricted to oral mucosa after intake of fresh fruits and vegetables. OAS diagnosis is based on suggestive clinical manifestations and can be confirmed with tests such as prick-to-prick skin test with the food implicated, which have a sensitivity > 90%, specificity 30-60%, positive predictive value (PPV) of 40% and negative predictive value (NPV) > 95%.