Familial progressive hyperpigmentation is characterized by patches of hyperpigmentation, present at birth, which increase in size and number with age. This is a genetic disease, however the gene that accounts for this spotty darkening of the skin has yet to be discovered. Although rare, the congenital disease is most prevalent among populations originating from China. : 858

See also
Skin lesion

References

The American Journal of Human Genetics 84, 672–677, May 15, 2009


== External links ==
Other, newer methods use colorimetric or fluorescence-labeled technology in the place of radioactive isotopes.The RAST methodology was invented and marketed in 1974 by Pharmacia Diagnostics AB, Uppsala, Sweden, and the acronym RAST is actually a brand name. In 1989, Pharmacia Diagnostics AB replaced it with a superior test named the ImmunoCAP Specific IgE blood test, which uses the newer fluorescence-labeled technology.American College of Allergy Asthma and Immunology (ACAAI) and the American Academy of Allergy Asthma and Immunology (AAAAI) issued the Joint Task Force Report "Pearls and pitfalls of allergy diagnostic testing" in 2008, and is firm in its statement that the term RAST is now obsolete:

The term RAST became a colloquialism for all varieties of (in vitro allergy) tests. This is unfortunate because it is well recognized that there are well-performing tests and some that do not perform so well, yet they are all called RASTs, making it difficult to distinguish which is which. For these reasons, it is now recommended that use of RAST as a generic descriptor of these tests be abandoned. The updated version, the ImmunoCAP Specific IgE blood test, is the only specific IgE assay to receive Food and Drug Administration approval to quantitatively report to its detection limit of 0.1kU/L. Medical specialty
An allergist is a physician specially trained to manage and treat allergies, asthma, and the other allergic diseases.