Eosinophilic esophagitis (EoE) is a chronic inflammation of the esophagus that has been considered an allergic phenomenon based on its similarities to other allergic conditions. More specifically, EoE has been considered a form of food allergy because of patient sensitizations to foods and improvements in symptoms and inflammation after food eliminations. This article presents the currently available evidence regarding the classification of EoE as an allergic condition, the involvement of foods in disease pathogenesis, and the value of different types of allergy testing and elimination diets in management of EoE. Using the search engines PubMed and Ovid, English literature in the past 10 years was reviewed with the use of the following key words: eosinophilic esophagitis, EoE epidemiology, EoE pathophysiology, food allergy, eosinophils, skin-prick testing, atopy patch testing, elemental diet, test directed elimination diet, six food elimination diet. Studies of EoE epidemiology and pathophysiology support the link between EoE and allergy in general, and studies of food allergy testing and elimination diets have supported a link between EoE and food allergy. Although food elimination diets cause resolution of symptoms and pathology in pediatric EoE, the results of testing and diet elimination studies are not as clear in adults, and aeroallergen sensitizations may play a larger role in adult EoE pathophysiology. Although several studies in children and adults support considering EoE a form of food allergy, the usefulness of skin-prick testing and atopy patch testing for food allergies and the optimal elimination diet for disease management are still uncertain.

The lack of C1 inhibitor function that results in excessive production of bradykinin causing the angioedema seen in hereditary angioedema (HAE) is well established. Several drugs have been developed to treat and prevent attacks in patients suffering from HAE due to C1 inhibitor deficiency (C1-INH-HAE). Plasma-derived C1INH has been used to replace the deficiency of C1 inhibitor (C1INH) and has been approved for both treatment of attacks and for prophylactic therapy to prevent attacks. Plasma kallikrein inhibitor (ecallantide) and bradykinin receptor antagonist (icatibant) are both effective for treatment of acute attacks, but their short half-life limits the use for prophylaxis. Androgens, in particular danazol, are effective for long-term prophylaxis, but adverse event profile can limit its use. Recombinant C1 inhibitor derived from transgenic rabbits has recently been approved for use in treatment of C1-INH-HAE attacks and is effective and appears safe with minimal adverse event profile.

Hereditary angioedema (HAE) with C1-inhibitor (C1-Inh) deficiency (C1-Inh-HAE) is a rare, life-threatening, and disabling genetic disorder characterized by self-limited tissue swelling caused by deficiency or dysfunction of C1-Inh. Our aim in this update is to discuss new advances in HAE therapy, focusing mainly on the various treatment options that have become available recently and also drugs that are under trial for prophylaxis to prevent attacks. There is a paradigm shift to where the treatment of HAE is headed, focusing now on prophylactic treatment rather than abortive management.

Although Hyper-IgE Syndrome (HIES) is a rare immunodeficiency disorder, presenting symptoms may be as common as lung and skin infections. Symptoms are usually nonspecific such as recurrent abscesses, folliculitis, and pneumonias along with skeletal abnormalities. Careful history of susceptibility to skin and lung infections, thorough family history, and findings on physical exam can guide towards the diagnosis of this often-eluded condition. Early optimization of therapy with prophylactic antibiotics can prevent recurrent infections and future complications and improve quality of life and longevity of survival. We present a case of a young female with Hyper-IgE Syndrome with a novel mutation in STAT 3 gene who initially presented with long standing history of intractable skin abscesses being managed as Hidradenitis Suppurativa.