All of the following are features of Hyper-IgE syndrome, except:
**Core Concept**
Hyper-IgE syndrome, also known as Job syndrome, is a rare primary immunodeficiency disorder characterized by elevated levels of Immunoglobulin E (IgE), eczema, and recurrent cutaneous and pulmonary infections. This condition results from mutations in the STAT3 gene, leading to impaired T-cell function and increased IgE production.
**Why the Correct Answer is Right**
The correct answer features of Hyper-IgE syndrome include eczema, recurrent cutaneous and pulmonary infections, and elevated IgE levels. The condition is often associated with characteristic facial features, such as a broad forehead, a prominent jaw, and a high-arched palate. Additionally, patients with Hyper-IgE syndrome may experience skeletal abnormalities, including osteoporosis and scoliosis. The elevated IgE levels contribute to the development of eczema and increased susceptibility to infections.
**Why Each Wrong Option is Incorrect**
**Option A:** Elevated IgE levels are a hallmark of Hyper-IgE syndrome, so this option is incorrect.
**Option B:** Recurrent cutaneous and pulmonary infections are common in patients with Hyper-IgE syndrome, making this option incorrect.
**Option C:** Eczema is a characteristic feature of Hyper-IgE syndrome, so this option is incorrect.
**Clinical Pearl / High-Yield Fact**
Hyper-IgE syndrome is often referred to as Job syndrome, named after the Swiss farmer who first described the condition in 1954. The condition is characterized by a distinctive combination of eczema, recurrent infections, and elevated IgE levels.
**Correct Answer: C. Elevated IgE levels are a hallmark of Hyper-IgE syndrome, so this option is incorrect.**