الفهرس 
STRIAE DISTENSAE: OVERVIEWOnly 14 pages are availabe for public view
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Abstract
Striae distensae are well recognized common skin condition that rarely causes some significant medical problem but is often a significant source of stress to those affected. They arise from progressive and rapid stretching of the dermis. The classic anatomical sites affected include the abdomen and breast for pregnancy- related striae, the outer thighs or lumbosacral regions in adolescent boys, and the buttocks, thighs, upper arms and breasts in adolescent girls.
Striae distensae progress through three stages of maturation: the acute stage is characterized by red and slightly raised striae (rubra), the subacute stage characterized by purpuric striae and the chronic stage characterized by hypopigmented and atrophic striae. High-resolution epiluminescence colorimetric assessment of SD identified four distinct types: striae alba, striae rubra, striae caerulea, and striae nigra.
The causes of striae are not clear; many authors had shown that the mechanical effect of stretching is the main cause, leading to rupture of the connective tissue framework as in pregnancy, obesity and weight lifting. Normal growth has been suggested as another cause, with these marks commonly developing during adolescence. Some authors suggested that damage of the tissues in a toxic way results in striations. Others suggested that SD are features of high serum levels of steroid hormones induced from local or systemic steroid therapy or Cushing’s syndrome.
The histological studies revealed, initial inflammatory changes followed by flattening and thinning of the epidermis due to underlying changes in the numbers and organization of collagen. In mature striae there is stretched collagen fibers aligned parallel to the skin surface, followed by subsequent loss of collagen and increased flattening of rete ridges.
Our study was conducted on 30 females aiming at studying the expression of estrogen androgen and glucocorticoid receptors in recent and mature striae. We included three groups of subjects: GroupI included 10 healthy females serving as controls, group II included 10 females having striae rubra and group III included 10 females having striae alba. Females of the control group were subjected to one punch biopsy, while females having striae alba and rubra were subjected to two punch biopsies from lesional and non lesional skin.
The H&E stained slides of striae rubra lesional skin showed that there is epidermal thinning, dermal edema, superficial and deep perivascular lymphocytic cuffing, there is vasodilatation and congestion in the dermis. However, in striae alba lesional skin The epidermis is thinned out and stretched. There was epidermal atrophy in some areas with loss and flattening of rete ridges.
The mallory stained slides of non lesional skin of striae rubra and alba showed that there was thin collagen bundles in the papillary dermis running in different directions. However, in the lesional skin of striae rubra there were thick collagen bundles in the papillary dermis many of them are seen running parallel to dermo-epidermal junction indicating increased fibrosis. In the lesional skin of striae alba there were thick collagen bundles in the papillary dermis running parallel to dermo-epidermal junction, much less vasculature and flattening of the dermo-epidermal junction. In other areas collagen appeared as disorganized and discontinuous bundles.
Statistical analysis of immunohistochemical results revealed that there was a highly significant decrease in ERβ expression in the epidermis and dermis of striae rubra and alba as compared to control group and a significant increase in the epidermis of striae alba than striae rubra as regards the lesional skin. However, in the non lesional skin there was a highly significant decrease in the ERβ expression in the epidermis of striae rubra than the control group and a significant increase in the epidermis of striae alba than striae rubra. As regards the dermis of non lesional skin there was a significant decrease in ERβ expression in striae rubra than the control group and a highly significant increase in striae alba than the control group and striae rubra. On comparing the ERβ expression between lesional and non lesional skin in striae rubra and striae alba it was found that there was a highly significant decrease in lesional than non lesional skin as regards the epidermis. In the dermis of striae alba there was a highly significant decrease in the lesional than non lesional skin.
On studying the expression of AR there was a significant increase in the epidermis of lesional skin of the striae alba than striae rubra and control group and a significant decrease in the dermis of striae alba than striae rubra and control group. However, as regards the non lesional skin there was a significant decrease in AR expression in the epidermis and dermis of striae rubra than control group and a highly significant decrease in the dermis of striae alba than the control group and a significant decrease in the dermis of striae alba than striae rubra. On comparing the AR expression in lesional and non lesional skin there was a highly significant increase in the lesional than non lesional skin of striae alba as regards the epidermis and a significant increase in the lesional than non lesional skin as regards the dermis.
Statistical analysis of immunohistochemical results of the GR expression revealed that it increased highly significantly in the epidermis and dermis of lesional skin of striae rubra and alba than the control group. However, in the non lesional skin there was a significant increase in the GR expression in the epidermis and dermis of striae rubra and alba than the control group and a significant increase in the dermis of striae alba than striae rubra. There was a highly significant increase in the GR expression in the lesional than non lesional skin as regards the epidermis and a significant increase in the lesional than non lesional skin as regards the dermis of striae rubra.
To conclude that there is a relation between the ER, AR and GR expression and the pathogenesis of striae distensae especially GR which was increased significantly in the lesional skin of striae rubra and striae alba and there is variability in the hormonal expression in the different stages of striae distensae. There are also, differences in the ER, AR and GR expression between the lesional and non lesional skin in the same patient. The quality of collagen content and the epidermal thickening differ in different stages of striae distensae as there is epidermal thinning and disorganization of collagen with maturation of striae distensae.