Introduction:

Klippel-Trenaunay Syndrome (KTS) is a rare, complex congenital disorder characterized by a triad of capillary malformations (port-wine stains), venous varicosities, and limb hypertrophy. While typically unilateral, phenotypic expression varies significantly. We present a case of an adolescent male exhibiting extensive cutaneous involvement and mixed vascular anomalies.

Case Presentation:

A 16-year-old male presented for evaluation of congenital vascular abnormalities. Physical examination revealed an extensive capillary malformation (port-wine stain) involving the left chest and abdomen, extending to the bilateral lower extremities. Significant varicosities were noted in the bilateral lower limbs, indicative of chronic venous insufficiency. Additionally, a distinct haemangioma was identified on the left ankle. Assessment of limb proportions demonstrated localised soft tissue and bony hypertrophy of the right foot, confirming the clinical triad characteristic of KTS. Diagnosis was clinical, supported by the presence of the defining triad. Doppler ultrasound was utilised to assess deep venous patency and characterise the extent of the varicosities and the ankle haemangioma. The patient's presentation aligns with the somatic mosaicism often associated with PIK3CA mutations, which can lead to tissue overgrowth and vascular dysplasia.

Management:

Management for this patient focused on symptom alleviation and prevention of complications. Conservative measures, including graduated compression therapy, were initiated to manage venous hypertension and oedema in the lower limbs. The patient is under multidisciplinary surveillance involving dermatology, vascular surgery, and orthopaedics to monitor the right foot hypertrophy and assess the need for potential sclerotherapy or epiphysiodesis (growth modulation) should functional impairment arise.

Conclusion:

This case highlights the heterogeneity of Klippel-Trenaunay Syndrome, particularly the presence of bilateral cutaneous and venous symptoms alongside unilateral hypertrophy. It underscores the necessity for thorough clinical evaluation and individualized, multidisciplinary care to optimize quality of life in adolescent patients transitioning to adulthood.