Clinical Challenge: Purplish spots on the scrotum

Angiokeratomas are telangectasias with overlyinghyperkeratosis. The case presented here is an example of angiokeratoma of thescrotum, also called angiokeratoma of Fordyce. There are five clinicalvariants: Angiokeratoma of the scrotum — characterized by purplish, reddish or black papules that stud the...

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Angiokeratomas are telangectasias with overlyinghyperkeratosis. The case presented here is an example of angiokeratoma of thescrotum, also called angiokeratoma of Fordyce. There are five clinicalvariants:

1. Angiokeratoma of the scrotum — characterized by purplish, reddish or black papules that stud the scrotum. The papules are usually asymptomatic, but may bleed if they are significantly traumatized.
2. Solitary or multiple angiokeratomas — this type of angiokeratoma may be found incidentally on physical exam. It most commonly appears as small blue-black warty papules on the lower extremities, but can occur on any body area.
3. Angiokeratoma of Mibelli — in this variant, lesions develop in prepubertal or pubertal children and are usually located on the dorsal and lateral aspect of the digits. Lesions are sometimes associated with chilblains or acrocyanosis, and an autosomal dominant inheritance pattern has been described.
4. Angiokeratoma corporis diffusum — associated with several inherited metabolic diseases including X-linked recessive Fabry disease, patients with angiokeratoma corporis diffusum develop the disorder during late childhood adolescence. It is characterized by multiple clustered angiokeratomas in a “bathing-trunk” distribution. 
5. Angiokeratoma circumscriptum — develops during infancy or childhood with a female predominance, and appears in a unilateral distribution on the trunk, arms or legs.

Diagnosis & Treatment

Clinical diagnosis is based on the characteristic appearance of angiokeratomas.A biopsy may be performed when the diagnosis is in doubt.

Angiokeratoma lesions are not consistent with any of the other answerchoices. Malignant melanoma may rarely be confused with solitaryangiokeratomas, but in this instance the lesions are purplish-red and easily identifiedas vascular lesions. Angiofibromas, also called fibrous papules, most commonlypresent as a small dome-shaped papules on the nose. Angiosarcoma commonlypresents as a bruise-like macule or patch on the head and neck region of anelderly individual, and angiolipoma presents as a soft subcutaneous nodule,usually on the forearms of young adults. Cherry angiomas are bright red dome-shapedpapules that commonly develop on the trunk and extremities of adults. 

Angiokeratoma treatment options include excision, laser ablation orelectrosurgery. However, for most patients reassurance is sufficient.

Adam Rees, MD, is agraduate of the University of California Los Angeles School of Medicine and aresident in the Department of Dermatology at Baylor College of Medicine inHouston.

References

1. Bolognia J, Jorizzo JL, Rapini RP. “Chapter 106: Other Vascular Disorders.” Dermatology (2nd ed.) St. Louis, Mo.: Mosby/Elsevier, 2008.
2. James WD, Berger TJ, Elston DM et al. “Chapter 28: Dermal and Subcutaneous Tumors.” Andrews’ Diseases of the Skin: Clinical Dermatology. Philadelphia: Saunder Elsevier, 2006.