Dr Edgar undertakes outpatient clinics at the Royal Victoria Hospital, Royal Belfast Hospital for Sick Children, Belfast City Hospital and Ulster Independent Clinic. He sees both children and adults.

Most referrals are for the diagnosis of underlying immune deficiency, allergic or autoimmune disorders or for advice on management of these conditions.

Common symptoms of immune deficiency in young children include failure to grow normally, diarrhoea and repeated chest infections. In adults it is most often repeated infection of the chest, ear, nose or throat.

In its most severe form, allergic disease presents with life threatening collapse and breathing difficulty (anaphylaxis), but less severe symptoms include itchy rashes and swelling (urticaria and angioedema), or upper airway symptoms of itchiness of the eyes and nose or wheeze.

Autoimmune diseases may present in many ways including with joint problems, skin rashes, or symptoms related to the affected organ, eg: thyroid, lungs, kidney or liver.