Kyrle disease - Skin
The cause of Kyrle's disease is unknown, but the pathomechanisms are thought to be multifactorial, including mechanical injury (especially from scratching), abnormal metalloproteinase activity, and transforming growth factor (TGF)-beta3 overexpression. Associations with nephropathy secondary to diabetes and with congestive heart failure and liver disease have been proposed. Age of onset is generally between 20 and 63 with an average age of onset of 30 years old. There seems to be no predilection for sex or race/ethnicity. The disease is rare except when seen in association with renal failure and is not uncommon in hemodialysis patients who have pruritus. Kyrle's lesions are found in about 10% of patients on hemodialysis secondary to diabetic nephropathy. Other precipitating factors that have been postulated include infection, disorder of vitamin A metabolism, and genetics (it has been hypothesized that this is an autosomal recessive genodermatosis).
Kyrle's disease classically presents as multiple discrete hyperkeratotic follicular (predominantly) and parafollicular eruptive papules with central crust or hyperkeratotic plug. When central plugs are removed, a pit-like depression remains (Kyrle's phenomenon). Pruritus may be present. Koebner's phenomenon (lesions forming at sites of skin trauma) is not generally seen, in contrast to some of the other perforating disorders. The predominant material that is extruded via transepidermal elimination in Kyrle's disease is keratin; elastic fibers and collagen can be present as well but are more prominent in other perforating disorders.
Pediatric Patient Considerations:
Cases documented in children are very rare.
L87.0 – Keratosis follicularis et parafollicularis in cutem penetrans
34042008 – Hyperkeratosis follicularis in cutem penetrans
- Excoriations from a variety of causes (example: prurigo simplex)
- Prurigo nodularis
- Arthropod bites
- Perforation of exogenous foreign material
- Perforation of endogenous substances
- Multiple keratoacanthomas
- Hypertrophic lichen planus (resembles early non-verrucous stage but missing central hyperkeratotic plug)
- Darier's disease (could be confused with large verrucous plaque form of Kyrle's disease)