Cutaneous Signs of Vascular Disorders: Idiopathic Leukocytoclastic Vasculitis

By Robert P. Blereau, MD

A 16-year-old girl was bothered by ankle pain and “red spots” on her lower legs. These symptoms cleared in a few days without treatment. Six weeks later, after returning from an all-day outing at a fair, she noticed that the spots had reappeared (A) and hemorrhagic lesions had developed on the right ankle (B) and left heel (C). After removing her shoes, the teenager felt severe pain in both ankles, particularly the right Unable to walk, the patient was taken to the emergency department the following morning. She was afebrile, had no other lesions or joint pain, and was taking no medications. The complete blood cell count and sedimentation rate were normal. Antinuclear antibody titer was negative. An elliptical incisional biopsy was performed on the large left heel lesion, and an excisional biopsy was done on the purpuric lesion on the same leg. Microscopically, both sites revealed small vascular structures, primarily capillaries, surrounded by abundant polymorphonuclear leukocytes and few eosinophils, evidence that confirmed the diagnosis of leukocytoclastic vasculitis. Leukocytoclastic, or hypersensitivity, vasculitis is a neutrophilic inflammation of small blood vessels.1Symptoms may include purpura, malaise, myalgias, and fever; oligoarthritis or monarthritis is associated with 40% of cases.2 Three characteristics are significant in making this diagnosis:

  • The purpura is nonblanching.
  • Purpuric patches are found on dependent areas of the body; symmetric distribution on the legs, thighs, and buttocks is typical.
  • Each macule is regular and approximately circular.
The course of leukocytoclastic vasculitis generally is benign. This patient was treated with oral prednisone(, and her condition promptly improved.
References

1. Habif TP. Clinical Dermatology: A Color Guide to Diagnosis and Therapy. 3rd ed. St Louis: Mosby; 1996:579-582.
2. Olewiler SD. Photoclinic: leukocytoclastic vasculitis.Consultant. 1994;34:1482-1483.