Klippel-Trenaunay-Weber syndrome (KTWS) is a rare congenital disease characterized by limb hypertrophy affecting bones and soft tissues, with extensive flat angiomas, varicose veins, and other vascular abnormalities, such as arteriovenous fistulas. Its incidence is 1: 100,000 people. The aim of this work was to describe a rare case of bilateral KTWS, confirmed with clinical and imaging findings in a 9-year-old male, with a history of lower gastrointestinal bleeding, left inguinal herniorrhaphy and ipsilateral orchidopexy. In both lower limbs, hemangiomatous lesions and muscle hypertrophy were identified, and in the left lower limb edema was identified with absence of the second and third toes due to a surgical history of amputation. Additionally, the patient presented cervical and inguinal lymphadenopathy. Among the important radiographic findings, in the left lower limb femur a thin bony cortex was observed. KTWS typically affects the lower limbs unilaterally; this is an infrequent case of bilate- ral affection (predominantly left). Some patients have visceral involvement with lower gastrointestinal bleeding, as well as genitourinary alterations, present in 30 % of cases. The presentation of lymphadenopathy is unusual.

KEY WORDS: Klippel-Trenaunay-Weber syndrome; Osteomuscularhypertrophy; Vascularabnormalities.