クリッペル・トレノネー・ウェーバー症候群

Combined vascular malformations are complex, heterogeneous lesions increasingly classified by anatomic components and genetic drivers, specifically the PI3K/AKT/mTOR pathway (PROS) and RASA1 mutations. These syndromes, including Klippel-Trenaunay, CLOVES, and capillary malformation-arteriovenous malformation, present with soft-tissue hypertrophy, skeletal overgrowth, and varied vascular anomalies. Effective management requires a multidisciplinary approach to address complications such as thromboembolism, localized intravascular coagulopathy, and limb-length discrepancy. Diagnostic evaluation relies on ultrasound and MRI. Therapeutic interventions have evolved from conservative compression and sclerotherapy to targeted pharmacotherapy (sirolimus, alpelisib) and individualized surgical debulking, with the aim of improving functional outcomes and quality of life.

INTRODUCTION: Klippel-Trénaunay syndrome (KTS) is a rare congenital syndrome characterized by the triad of capillary malformation, varicosities, and limb hypertrophy, with an incidence of 2-5 per 100,000. Gastrointestinal (GI) involvement in KTS may be present in over 30% of patients, typically presenting with pain and bleeding. While bleeding is a well-described symptom of GI involvement in KTS in the medical literature, diarrhea remains an uncommon and underreported manifestation. This report highlights this unique finding and the diagnostic complexity it presents. CASE PRESENTATION: A 64-year-old male presented to the hospital with recurrent foul-smelling bloody diarrhea over the past two months. He had been previously diagnosed and treated for ulcerative colitis. Physical examination revealed pallor, macrodactyly, and segmental hypertrophy of the lower left limb. Investigations demonstrated severe iron-deficiency anemia, splenomegaly, fundal varices, and a continuous 15-cm colonic involvement from the anal verge with varicosities and bleeding. This led to the establishment of a diagnosis of KTS. CONCLUSION: This case highlights the diagnostic challenge that may arise from the complexity and variability of KTS presentations, which can mimic inflammatory bowel disease (IBD) due to findings like bloody diarrhea and extensive colonic involvement. Although diarrhea is rarely reported as a manifestation of KTS, it might result from existing GI vascular and lymphatic malformation, potentially leading to protein-losing enteropathy. Awareness of this atypical presentation and early multidisciplinary evaluation are crucial for symptom control, preventing complications, and improving quality of life.

Bloom syndrome is a rare autosomal recessive chromosomal instability disorder characterized by growth deficiency and early-onset malignancies, and its coexistence with multiple vascular neurocutaneous syndromes is exceptionally uncommon. We report an 8-year-old girl who presented with severe growth failure and persistent pancytopenia. Bone marrow examination showed hypocellularity with monosomy 7, consistent with myelodysplastic neoplasm, and molecular analysis identified a homozygous pathogenic BLM variant (NM_000057.4:c.796C>T; p.Arg266Ter). Clinically, she exhibited overlapping neurocutaneous features within the spectrum of Sturge-Weber syndrome, Klippel-Trénaunay syndrome, and phakomatosis pigmentovascularis. The course was complicated by severe sepsis, leading to death before hematopoietic stem cell transplantation could be performed. This case highlights the importance of considering inherited cancer predisposition syndromes in children with cytopenia, growth failure, and complex neurocutaneous phenotypes.

INTRODUCTION: Parkes-Weber Syndrome (PWS) is a rare congenital vascular disorder of unknown etiology for which no established curative treatments currently exist. High-flow arteriovenous malformations (AVMs) in PWS can lead to severe complications, including the need for major limb amputation. CASE PRESENTATION: A woman in her 50s presented with progressive swelling, severe pain, and impaired ambulation in her right thigh. She was diagnosed at age 14 with varicose veins in her right lower limb and a 1.5-cm limb-length discrepancy, with the right leg longer than the left, and later developed an arteriovenous fistula at age 23. By age 54, examination revealed extensive swelling and hardening of the thigh, with CT imaging showing numerous abnormal vessels forming a nidus and a ruptured hematoma measuring 17 × 14 × 18 cm. She was referred to our facility after unsuccessful attempts to remove hematoma removal at a previous institution and was diagnosed with PWS. Preoperative embolization of multiple niduses was performed to reduce blood flow, although perfusion to other niduses persisted. Hematoma removal was conducted in 2 stages. The first surgery involved securing arterial flow with a stent graft and partial excision of the hematoma (13 h 39 min; blood loss: 9105 mL). Nineteen days later, a second surgery was performed to remove approximately 90% of the hematoma while preserving the remaining wall to avoid complications (8 h 14 min; blood loss: 5533 mL). The patient recovered without complications and was discharged 2 weeks following the second surgery. Minor delays in wound healing resolved within 6 months, and she remains recurrence-free at 48 months. CONCLUSIONS: This case highlights the complexity of managing PWS and underscores the importance of individualized, multidisciplinary care.