• Clinical pattern of multiple, bilateral, cutaneous, tender, and somewhat painful inflammatory, nonulcerating, and nonscarring eruptions that undergo characteristic color changes ending in temporary bruise-like areas
• Occurs most commonly on the extensor surface of the shins, less common on thighs and forearms
• Often idiopathic, but may be seen as a response to a variety of clinical entities
• Usually subsides in 3–6 weeks without scarring or atrophy
• Synonym(s): Dermatitis contusiformis

ALERT
Pediatric Considerations
Incidence equal, male and female

Pregnancy Considerations
May have repeat outbreaks during pregnancy

• Predominant age: 20–30 years
• Predominant sex: Female > Male (3:1)

Incidence
Unknown

Prevalence
Unknown

See “Etiology.”

• Idiopathic: 37–60%
• Bacterial: Streptococcal infections (most common cause in children), tuberculosis, leprosy, Yersinia enterocolitica, tularemia, Campylobacter, salmonella, Shigella, gonorrhea
• Sarcoid
• Drugs: Sulfonamides, oral contraceptives, bromides
• Pregnancy
• Deep fungal: Dermatophytes, coccidioidomycosis, histoplasmosis, blastomycosis
• Viral/Chlamydial: Infectious mononucleosis, lymphogranuloma venereum, paravaccinia
• Enteropathies: Ulcerative colitis, Crohn disease, Behçet disease (1), celiac disease (2)
• Malignancies: Lymphoma/leukemia, sarcoma, post radiation therapy

See “Etiology.”