Differentiating Common Sexually Transmitted Genital Lesions

Finding

Other Features

Cause*

Solitary painless ulcer

Indurated, nontender or only slightly tender

Relatively nontender adenopathy

Syphilitic chancre

Clusters of small, painful superficial ulcers on an erythematous base

Sometimes with vesicles

Inguinal adenopathy

Herpes simplex virus infection

Shallow painful ulcer

Nonindurated, tender ulcers with ragged, undermined edges and a red border, varying in size and often coalescing

Regional adenopathy

Chancroid

Small papule or ulcer, often asymptomatic or unnoticed

Severely tender and painful adenopathy, sometimes with distal lymphedema or drainage to the skin

Sometimes fever

Lymphogranuloma venereum

Multiple, shallow ulcers

Characteristic extragenital lesions and burrows

Excoriated scabies

Multiple, shallow lesions

Visible lice, or egg sacs (nits) attached to hair shafts

Pediculosis pubis with excoriation

Elevated nodule that ulcerates and progressively expands

Velvety, malodorous, granulating lesions

No inguinal adenopathy

Granuloma inguinale

* Other causes of ulcers include mucous patches of secondary syphilis, erosive balanitis, gummatous ulceration of tertiary syphilis, Behçet syndrome, epithelioma, and trauma.