Striae distensae, more commonly known as “stretch marks,” are atrophic linear bands of skin that appear after certain precipitating factors such as pregnancy, steroid use, and dramatic changes in weight or muscle mass (Fig. 60.1). At presentation, they feature a purple or pink color (striae rubra) that fades to a paler white (striae alba) over time. They are most common in adult women.
(A) Striae alba at baseline. (B) Striae alba at 11 months follow-up after four treatments with a 1450-nm diode laser (Smoothbeam, Candela Corp., Wayland, MA) at energy settings of 13 to 14 J/cm2, using a 6-mm spot size with a pulse duration of 30 ms. Treatment was performed at intervals of 2 to 3 months
Race: more common in Caucasians
Sex: females > males (associated with puberty and pregnancy)
Precipitating factors: topical and oral steroid use, Cushing’s syndrome, pregnancy, breast-feeding, puberty, genetic collagen defects, and dramatic changes in weight, height, or muscle mass
There are changes in the extracellular dermal matrix including fibrillin, elastin, and collagen, resulting from prolonged stretching of the skin.
There are scar-like features. Typically, there is an atrophic epidermis with narrow collagen bundles arranged parallel to the skin surface. The rete ridges are effaced. In early striae, there is a superficial, deep, and interstitial lymphocytic perivascular infiltrate and occasional eosinophils. The infiltrate fades in older lesions.
Multiple symmetric linear band-like plaques of atrophic skin that present most commonly in the outer thighs, breasts, and buttocks of women along the lines of cleavage. They present with a pink/purple hue (striae rubra) and become paler with fine wrinkling over time (striae alba). Striae are largest and most abundant in patients with Cushing’s disease. In pregnancy, striae are most abundant on the abdomen. In weight lifters, they are most prominent on the shoulders. Topical corticosteroid use most commonly produces striae on the face, genitalia, flexural areas, and body folds.
The characteristic clinical appearance of striae negates any need for skin biopsy. Additional laboratory workup to rule out Cushing’s disease is indicated in the appropriate clinical setting.
Striae begin as pink or purple atrophic lesions that become paler and less obvious over time.
KEY CONSULTATIVE QUESTIONS