Adenosine deaminase (ADA) Overview Adenosine deaminase (ADA) deficiency is a rare, autosomal recessive metabolic disorder that impairs lymphocyte development and causes severe combined immunodeficiency (SCID). Without the ADA enzyme, toxic metabolites (such as dATP) accumulate, destroying T, B, and NK cells. Untreated ADA-SCID is typically fatal in infancy. Symptoms The signs and symptoms of ADA deficiency generally fall into three categories :1. Severe Immune Deficiency (ADA-SCID)Around 80% of cases are severe and appear within the first 6 months of life. Without treatment, these are usually fatal within the first or second year. Recurrent Infections: Frequent, persistent, or unusual cases of pneumonia, chronic diarrhea, thrush (oral yeast), and skin rashes. Failure to Thrive: Severely slow growth in height and weight, often resulting in developmental delays. No Functional Immunity : A near-complete lack of T-cells, B-cells, and natural killer (NK) cells. 2. Skeletal & Non-...
Autosomal Dominant Hyper IgE Syndrome Overview Autosomal dominant hyper IgE syndrome (AD-HIES) is a rare multisystem primary immunodeficiency disorder. Symptoms often become apparent early during infancy or childhood. The disorder is characterized by repeated bacterial infections of the skin and lungs (pneumonia), skeletal abnormalities, and characteristic facial features. The first symptom is often the development of a dry, red flaky skin rash (eczema) at birth or early during infancy. Researchers have discovered that mutations in the STAT3 gene cause AD-HIES in over 60% of the patients. Most cases of AD-HIES occur as the result of a new mutation in this gene. There are two main forms of hyper IgE syndrome – one inherited in an autosomal dominant pattern and one in an autosomal recessive pattern. Both involve defects of the immune system and elevated levels of immunoglobulin E (hyper IgE) in the blood. For years, researchers considered them different expressions of the same disorder, ...