Growing asymptomatic birthmark on boy’s left ankle

October 1, 2015

A healthy 10-year-old boy is brought to your office by his worried father for evaluation of an asymptomatic birthmark on his left ankle. It has grown proportionately and does not cause pain or interfere with normal function. What’s the diagnosis?

The Case

A healthy 10-year-old boy is brought to your office by his worried father for evaluation of an asymptomatic birthmark on his left ankle. It has grown proportionately and does not cause pain or interfere with normal function. 

NEXT: What's the diagnosis?

 

DERMCASE diagnosis: Venous malformation

Epidemiology

The overall incidence of congenital vascular malformations is 1.2%. Venous malformation is one of the more common forms. It occurs in 1 in 5000 to 10,000 live births. The most common site for the formation of venous malformations is on the lower limb.1

Pathophysiology

Vascular malformations are present at birth and do not regress.2 Venous malformations are simple, slow-flow vascular malformations.3 Venous malformations contain abnormally formed veins with less smooth muscle and are weak and dilated. Venous malformations can grow sporadically, especially during pregnancy, puberty, or after injury.4 Symptomatology can therefore vary greatly throughout a patient’s life.

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The exact cause of venous malformations is unknown, although there is a clear correlation with mutations to TIE2/TEK tyrosine kinase transmembrane receptor. A rare autosomal dominant form accounts for 1% to 2% of venous malformation cases. This autosomal dominant form has been mapped to a locus on chromosome 9p where there is a gain of function mutation on endothelial cell-specific tyrosine kinase receptor TIE2/TEK.5 Furthermore, about half of the spontaneous cases will exhibit a mutation in TIE2.6

Investigations

Imaging is integral when planning treatment for symptomatic presentations. On ultrasound, slow-flow venous malformations are solid, compressible echogenic masses with phleboliths (even in patients aged as young as 2 years). On Doppler ultrasound, no flow or a monophasic venous flow pattern are typical findings.7

Treatment

Vascular malformations will persist unless treated.2 Size and depth of the lesion, along with the tissue types involved, dictate treatment options. For malformations deep in the dermis that are not symptomatic, treatment is not necessary; however, it can improve the cosmetic effect. As veins swell and become painful, compression stockings provide symptomatic relief.8 Surgery, laser therapy, and sclerotherapy are proven treatments used in combination to control, but not cure, the malformations.2 To ameliorate bleeding risks, percutaneous sclerotherapy should be performed before surgery.4 Partial resection can precipitate rapid expansion of the lesion. This risk must be considered when planning interventions.4

Differential diagnosis

Capillary malformation. These are flat, red, or purplish benign lesions. The “stork bite” or “angel kiss” are common congenital capillary malformations that occur in up to 70% of infants. These often regress within the first year of life. The nevus flammeus, also known as port-wine stains, occur in 0.3% of live births and can persist for the patient’s lifetime.9

Lymphatic malformation. Lymphatic malformations can cause local spongey swelling. They can also appear as collections of hypopigmented vesicles, like frog spawn, and are present from birth.9

Arteriovenous malformation. Arteriovenous malformations are tense, high-flow lesions that are present from birth. They can have a unique appearance on Doppler imaging and can have a bruit.9

Infantile hemangioma. Infantile hemangiomas are raised lesions that grow in the first year of life and then begin to regress. Often reddish looking, these can also be flesh colored.9

Outcome

In this case, the boy’s venous malformation was asymptomatic and there were no sinister changes or any suggestion that the malformation was altering the growth of his leg. No further investigations or treatments were indicated.

References

1. Lee B-B, Laredo J, Neville RF. Epidemiology of vascular malformations. In: Mattassi R, Loose DA, Vaghi M, eds. Hemangiomas and Vascular Malformations: An Atlas of Diagnosis and Treatment. Milan, Italy: Springer Milan;2015:165-170.  

2. Richter GT, Friedman AB. Hemangiomas and vascular malformations: current theory and management. Int J Pediatr. 2012;2012:645678. Epub May 7, 2012.

3. Dasgupta R, Fishman SJ. ISSVA classification. Semin Pediatr Surg. 2014;23(4):158-161.

4. Dubois J, Garel L. Imaging and therapeutic approach of hemangiomas and vascular malformations in the pediatric age group. Pediatr Radiol. 1999;29(12):879-893.

5. Breugem CC, van Der Horst CM, Hennekam RC. Progress toward understanding vascular malformations. Plast Reconstr Surg. 2001:107(6):1509-1523.

6. Soblet J, Limaye N, Uebelhoer M, et al. Variable somatic TIE2 mutations in half of sporadic venous malformations. Mol Syndromol. 2013;4(4):179-183.

7. Lowe LH, Marchant TC, Rivard DC, Scherbel AJ. Vascular malformations: classification and terminology the radiologist needs to know. Semin Roentgenol. 2012;47(2):106-117.

8. Mattassi R. Treatment of venous malformations. In: Mattassi R, Loose DA, Vaghi M, eds. Hemangiomas and Vascular Malformations: An Atlas of Diagnosis and Treatment. Milan, Italy: Springer Milan;2009:223-230.

9. Cohen BA. Another baby and another cutaneous lesion-and more on efficient recognition and management, Part 2. Contemporary Pediatrics. 2004;29(10):31-57.           

Ms Ward is currently a fifth year MBBS student in the GKT School of Medical Education at King’s College, London, United Kingdom. Dr Cohen, section editor for Dermcase, is professor of pediatrics and dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland.