Nezelof Syndrome. Combined Immunodeficiency.
Incidence
Nezelof's syndrome is an inherited condition that is usually diagnosed in infancy and early childhood (usually within the first 6 months of life), due to the abnormal infections and illness that result in early life.
Clinical Characteristics
Nezelof Syndrome is a very rare immune disorder where the cells of the body that normally fight against infections do not function properly. This syndrome is also sometimes called combined immunodeficiency (CID) because both of the immune system cells (B cells and T cells) do not work properly. It is different from severe combined immunodeficiency (SCID) because there is often some function of the B and T cells present, and so it is not as severe. As more information becomes available about the immune system, several different causes of Nezelof syndrome are becoming known. The two main ones currently are cartilage hair hypoplasia and PNP, a deficiency of a protein that helps the body process old DNA. A child with Nezelof's syndrome may have the following symptoms: persistent diarrhea, an unusually high number of bacterial, viral, fungal, or protozoan infections, infections that are more life threatening, and less responsive to treatment than in other infants with a functional immune system. Other illnesses including pneumonia, meningitis, and blood infections occur. Exposure to chickenpox may cause a dangerous infection of the lungs and brain. Chronic lung inflammation is a common complication of pneumonia.
Precipitants
None.
Provocation Tests
None
Diagnostic Procedures
A child may be diagnosed with this condition after their physician notices that they have been suffering from persistent, recurrent infections, or severe infections from microorganisms that do not usually cause severe infection. Doctors may suspect that the child has an immunodeficiency disorder, and diagnose Nezelof's on the basis of blood test results. Tests that may be performed might include a white blood cell count, a T lymphocyte count, and other tests that measure the level of immune cells in the body. In the case of a PNP enzyme deficiency, a test can be performed that helps determine whether this enzyme is functioning properly.