Chapter 60: Striae Distensae

INTRODUCTION

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.

EPIDEMIOLOGY

Incidence: common

Age: puberty, pregnancy

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

PATHOGENESIS

There are changes in the extracellular dermal matrix including fibrillin, elastin, and collagen, resulting from prolonged stretching of the skin.

PATHOLOGY

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.

PHYSICAL 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.

DIFFERENTIAL DIAGNOSIS

Linear focal elastosis.

LABORATORY EXAMINATION

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.

COURSE

Striae begin as pink or purple atrophic lesions that become paler and less obvious over time.

KEY CONSULTATIVE QUESTIONS

• Duration

• Skin phototype

• Pregnancy

• Assess for symptoms of Cushing’s disease

• Use of corticosteroids

• History of weight change

• History of ...