X-linked reticulate pigmentary disorder
|X-linked reticulate pigmentary disorder|
|Classification and external resources|
X-linked reticulate pigmentary disorder (also known as "Familial cutaneous amyloidosis," "Partington amyloidosis," "Partington cutaneous amyloidosis," "Partington syndrome type II," "Reticulate pigmentary disorder", and "X-linked reticulate pigmentary disorder with systemic manifestations") is a cutaneous condition that has been described in adult women that had linear streaks of hyperpigmentation and in which male patients manifested a reticulated mottled brown pigmentation of the skin, which, on biopsy, demonstrated dermal deposits of amyloid.
The syndrome is also referred with the acronym X-Linked-PDR or even XLPRD.
It's a very rare disease, genetically determined, with a chronic course.
It was characterized in 1981.
Mutation of the POLA1 gene leads to loss of expression of the catalytic subunit of DNA polymerase-α and is responsible for XLPDR. Loss of POLA1 expression results in reduced levels of RNA:DNA hybrids in the cytosol and unexpectedly triggers aberrant immune responses (e.g. type I interferon production) which at least in part can account for the symptoms associated with XLPDR.
Affected males develop generalized reticular hyper pigmentation in early childhood. Hair often looks bedraggled or brushed backwards, hanging low on the forehead.
Among the associated extracutaneous manifestations are described:
- Respiratory infections
- Dyskeratosis corneal photophobia
- Hypohidrosis with large deficit of thermoregulation
- Growth retardation
- Gastrointestinal disorders
- Kidney disease
- Kidney stones
- Urinary infections
- Webbed feet or hands
- Electrolyte imbalance
- Retinitis pigmentosa
- Thyroid abnormalities
Each patient shows some of the symptoms listed above. Not every sick person will show all of the listed symptoms.
In females the disease is characterized by skin rashes linear hyper pigmentation following the Blaschko's lines, morphologically similar to stage 3 pigment incontinence. There are no systemic manifestations associated with XLPDR in females.
- Rapini, Ronald P.; Bolognia, Jean L.; Jorizzo, Joseph L. (2007). Dermatology: 2-Volume Set. St. Louis: Mosby. p. 630. ISBN 1-4160-2999-0.
- Partington MW, Marriott PJ, Prentice RS, Cavaglia A, Simpson NE (1981). "Familial cutaneous amyloidosis with systemic manifestations in males". Am. J. Med. Genet. 10 (1): 65–75. doi:10.1002/ajmg.1320100109. PMID 6794369.
- Starokadomskyy P, Gemelli T, Rios JJ, Xing C, Wang RC, Li H, Pokatayev V, Dozmorov I, Khan S, Miyata N, Fraile G, Raj P, Xu Z, Xu Z, Ma L, Lin Z, Wang H, Yang Y, Ben-Amitai D, Orenstein N, Mussaffi H, Baselga E, Tadini G, Grunebaum E, Sarajlija A, Krzewski K, Wakeland EK, Yan N, de la Morena MT, Zinn AR, Burstein E. "DNA polymerase-α regulates the activation of type I interferons through cytosolic RNA:DNA synthesis.". Nature Immunology. doi:10.1038/ni.3409.