Anogenital Abrasion

Synopsis

Genital abrasions may occur following accidental, self-inflicted, or sexually assaultive trauma. Dermatologic conditions causing pruritus can also lead to abrasions and excoriations. Acute abrasions with associated lacerations or extensive bruising of the penis, scrotum, or perineum are considered of moderate specificity of abuse. Injury to the genital area in children always gives cause for concern. Parents are often worried about permanent damage and are often concerned about sexual abuse.

Accidental injuries to the genitalia usually have a clear history with findings on examination consistent with that history. Straddle injuries are a type of accidental trauma that lead to compression of the soft tissues of the penis between the object and the pubic ramus, causing bruising, abrasions, and/or lacerations. In a typical straddle injury, one foot slips and the child falls forward, compressing the genital area (eg, on the monkey bars). This causes anteriorly placed abrasions and asymmetrical bruising of the genitalia. Scraping of the medial side of one thigh may also occur, especially if the object straddled has a rough surface (eg, the side of a swimming pool). Associated lacerations, if present, are most often superficial.

Stretch injuries, “the splits,” can result in superficial lacerations in the skin of the perineum.

Severe self-inflicted injury is unlikely because of the pain caused by self-trauma. Minor abrasions may occur if children scratch because of pinworm infection. Adolescents may cause minor injuries with masturbation.

Children with genital abrasions typically complain of genital pain, soreness, and, sometimes, dysuria when the urine passes over the abraded area.

The external genitalia of boys must also be evaluated for abrasions and lacerations possibly due to a bite. Often, there is associated erythema and/or ecchymosis. The urethral meatus may also have evidence of lacerations, erythema, and discharge.

Perineal irritation, abrasion, and erythema are common causes, most likely due secondarily to pruritus from contact dermatitis (often caused by diapers), seborrheic dermatitis, poor hygiene, and candidal lesions.

Since positive physical findings of sexual abuse occur infrequently, one cannot overemphasize that the history from the child still remains the single most important diagnostic feature in assessing whether a child has been sexually abused.