|Classification and external resources|
|ICD-10||D81.2 (ILDS D81.210)|
Omenn syndrome is an autosomal recessive severe combined immunodeficiency associated with mutations in the recombination activating genes (RAG1 and RAG2), affecting circulating levels of both B-cells and T-cells.
The symptoms are very similar to graft-versus-host disease (GVHD). This is because the patients have some T cells with limited levels of recombination with the mutant RAG genes. These T cells are abnormal and have a very specific affinity for self antigens found in the thymus and in the periphery. Therefore, these T cells are auto-reactive and cause the GVHD phenotype.
- Desquamation (shedding the outer layers of skin)
- Chronic diarrhea
- Erythroderma (widespread reddening of the skin)
- Hepatosplenomegaly (simultaneous enlargement of both the liver and the spleen)
- Leukocytosis (elevation of the white blood cell count)
- Lymphadenopathy (swelling of one or more lymph nodes)
- Persistent bacterial infections
- Elevated serum IgE