What are the IBMFS disorders?
Severe Congenital Neutropenia (SCN)
SCN patients have very low white
blood counts. Since white cells help the body to fight off
infection, children with this disorder develop serious infections
during infancy. The physical appearance is normal.
Males and females are affected equally.
- What are the major findings on physical examination?
- These patients have normal physical examinations.
- What is the age at diagnosis?
- The diagnosis is usually made in the first year of life.
- What is the pattern of bone marrow failure?
- The bone marrow of patients with SCN fails to produce a
specific type of white blood cell known as a "neutrophil".
- What specific kinds of cancer
(cancer of the blood and bone marrow)
- How is SCN specifically diagnosed?
- By doing a blood count and a bone marrow examination, doctors
can detect the specific absence of neutrophil white cells.
- Mutation analysis (genetic testing)
- Laboratories can now identify the genetic "error" (mutation)
in some patients, in a gene called ELANE (formerly ELA2).
- The disease usually occurs if a person has only one abnormal
This form is thought to be inherited
in an autosomal
- In some families, SCN occurs only if a person has two abnormal genes. This form of SCN is also known as
Kostmann Syndrome, and it is inherited
in an autosomal recessive
manner. The gene which causes this form of SCN is HAX1.
- A few patients have had mutations in other genes: GFI1 (dominant), G6PC3 (recessive), THC1/WASP (X-linked recessive).