Friction melanosis, friction amyloidosis, macular amyloidosis, towel melanosis: Many names for the same clinical entity
ABSTRACT Macular or friction amyloidosis is a cutaneous entity characterized by a brownish pigmentation distributed on the skin over bony regions of the trunk and limbs after the use, for many years, of a nylon towel or scrub brush to clean the skin. Electron microscopy is necessary for the diagnosis of this dermatosis and reveals deposits of amyloid in the papillary dermis. This condition is relatively unknown in Western countries. In this report, we describe 24 Italian patients affected by friction amyloidosis which was caused by the use of cotton towels, horse-hair gloves or artificial and rough sponges to clean their skin.
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- "Frequent involvement of back, extensor aspects of upper limbs and clavicular areas compared to sun-protected sites like lower back, legs, thighs, buttocks and breast would point to exposure of ultraviolet (UV) rays as an etiological factor in MA. Moreover, sunny weather contributing to increased pigmentation in PLCA has previously been reported. Sun-protected sites were involved in only 10% of our patients with sun-exposed sites being involved in a higher number of patients (64%). "
ABSTRACT: Macular amyloidosis (MA) is the most subtle form of cutaneous amyloidosis, characterized by brownish macules in a rippled pattern, distributed predominantly over the trunk and extremities. MA has a high incidence in Asia, Middle East, and South America. Its etiology has yet to be fully elucidated though various risk factors such as sex, race, genetic predisposition, exposure to sunlight, atopy and friction and even auto-immunity have been implicated. This study attempts to evaluate the epidemiology and risk factors in the etiology of MA. Clinical history and risk factors of 50 patients with a clinical diagnosis of MA were evaluated. Skin biopsies of 26 randomly selected patients were studied for the deposition of amyloid. We observed a characteristic female preponderance (88%) with a female to male ratio of 7.3:1, with a mean age of onset of MA being earlier in females. Upper back was involved in 80% of patients and sun-exposed sites were involved in 64% cases. Incidence of MA was high in patients with skin phototype III. Role of friction was inconclusive Lack of clear-cut etiological factors makes it difficult to suggest a reasonable therapeutic modality. Histopathology is not specific and amyloid deposits can be demonstrated only in a small number of patients. For want of the requisite information on the natural course and definitive etiology, the disease MA remains an enigma and a source of concern for the suffering patients.Indian Journal of Dermatology 03/2012; 57(4):269-74. DOI:10.4103/0019-5154.97662
- "The diagnosis of macular amyloidosis is based on long term persistence of the disorder, localized pruritus and constant scratching urge, greyishbrown pigmentation over the scapula and detection of amyloid in histologic slides (Shanon and Sagher 1970).Rippled pigmentation is not necessarily specific or diagnostic of amyloidosis and is associated with atopic dermatitis (Onuma et al.,1994). Siraqusa M et al described friction amyloidosis to be caused by the use of cotton towels, horse-hair gloves or artificial and rough sponges to clean the skin (Siraqusa et al., 2001). There is history of prolonged rubbing over a period of 2-5 years with various objects such as bath sponges, brushes, towels, plant sticks and leaves (Rasi et al., 2004; Shanon and Sagher 1970). "
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- "Epidermal hypermelanization is apparent in these types of hyperpigmentation, with marked dermal melanin deposition resulting from pigmentary incontinence [3,13–17] and melanin in the cytoplasm of dermal macrophages, with   or without    deposition of amyloid. We have also experienced patients with similar melanogenetic manifestation at sites of the body where repetitive friction is apparent (e.g., pigmentation of the nipple–areolar complex  , intertriginous parts of the body, and sites where underwear is attached or over a bony prominence ). "
ABSTRACT: The aim of this study was to investigate the possible pathological relation between mechanical stress and hyperpigmentation. We did this by investigating the influence of cyclic stretch on the expression of keratinocyte- and fibroblast-derived melanogenetic paracrine cytokines in vitro. Using primary human keratinocytes and fibroblasts, alterations of mRNA expression of melanogenetic paracrine cytokines due to cyclic stretch were investigated using a real-time polymerase chain reaction (PCR). The cytokines included basic fibroblast growth factor (bFGF), stem cell factor (SCF), granulocyte/macrophage colony-stimulating factor, interleukin-1α, and endothelin-1 (ET-1) for keratinocytes and bFGF, SCF, and hepatocyte growth factor for fibroblasts. The dose dependence of keratinocyte-derived ET-1 upregulation was further investigated using real-time PCR and an enzyme-linked immunosorbent assay. We also investigated the effects of cyclic stretch on the proliferation and differentiation of keratinocytes. Among the melanogenetic paracrine cytokines investigated, keratinocyte-derived ET-1 was consistently upregulated in all four cell lines. The degree of upregulation increased with the degree of the length and frequency of the stretch; in contrast, cell number and differentiation markers showed no obvious alterations with cyclic stretch. Keratinocyte-derived ET-1 upregulation possibly plays a significant role in the pathogenesis of pigmented disorders, such as friction melanosis, caused by mechanical stress.Biochemical and Biophysical Research Communications 05/2011; 409(1):103-7. DOI:10.1016/j.bbrc.2011.04.118 · 2.28 Impact Factor