Congenital angiodysplasia of the superficial venous system of the lower extremities in children

Biomedicine and diseases: the Klippel-Trenaunay syndrome, vascular anomalies and vascular morphogenesis

Vascular morphogenesis is a vital process for embryonic development, normal physiologic conditions (e.g. wound healing) and pathological processes (e.g. atherosclerosis, cancer). Genetic studies of vascular anomalies have led to identification of critical genes involved in vascular morphogenesis. A susceptibility gene, VG5Q (formally named AGGF1), was cloned for Klippel-Trenaunay syndrome (KTS). AGGF1 encodes a potent angiogenic factor, and KTS-associated mutations enhance angiogenic activity of AGGF1, defining 'increased angiogenesis' as one molecular mechanism for the pathogenesis of KTS. Similar studies have identified other genes involved in vascular anomalies as important genes for vascular morphogenesis, including TIE2, VEGFR-3, RASA1, KRIT1, MGC4607, PDCD10, glomulin, FOXC2, NEMO, SOX18, ENG, ACVRLK1, MADH4, NDP, TIMP3, Notch3, COL3A1 and PTEN. Future studies of vascular anomaly genes will provide insights into the molecular mechanisms for vascular morphogenesis, and may lead to the development of therapeutic strategies for treating these and other angiogenesis-related diseases, including coronary artery disease and cancer.

Klippel-Trénaunay syndrome: spectrum and management

OBJECTIVE

To describe a series of 252 patients with Klippel-Trénaunay syndrome (KTS), a rare congenital malformation characterized by the triad of capillary malformations, atypical varicosities or venous malformations, and bony or soft tissue hypertrophy usually affecting one extremity.

MATERIAL AND METHODS

We reviewed the clinical characteristics and findings in 136 female and 116 male patients with KTS who underwent assessment at Mayo Clinic Rochester between January 1956 and January 1995. In addition, management options are discussed.

RESULTS

Capillary malformations (port-wine stains) were found in 246 patients (98%), varicosities or venous malformations in 182 (72%), and limb hypertrophy in 170 (67%). All three features of KTS were present in 159 patients (63%), and 93 (37%) had two of the three features. Atypical veins, including lateral veins and persistent sciatic vein, occurred in 182 patients (72%). Operations performed in 145 patients with KTS included epiphysiodesis, stripping of varicose veins or venous malformations, excision of vascular malformations, amputations, and debulking procedures.

CONCLUSION

Most patients with KTS should be managed conservatively. The clearest indication for operation is a leg length discrepancy projected to exceed 2.0 cm at skeletal maturity, which can be treated with epiphysiodesis in the growing child. If a functioning deep vein system is present, removal of symptomatic varicosities or localized superficial venous malformations in selected patients can yield good results.

Klippel-Trénaunay syndrome: clinical features, complications, and management

Klippel-Trénaunay Syndrome (KTS) is rare and not well recognized among most physicians, which has lead to inappropriate management and delayed referral in many cases. Presented herein is the largest series ever reported from a single center in Saudi Arabia, comprised of 18 patients seen between 1990 and 1996, whose clinical features, complications, and management are discussed. All 18 patients had large angiomatous navei, hypertrophy of the soft tissue with bone overgrowth in the lower limbs, and extensive lower limb varicosities, which extended to the buttocks and lower abdomen in 2 patients. There were 4 patients who had undergone at least one operation for lower limb varicose veins prior to referral. The diagnostic workup and treatment for KTS is discussed in detail. It is essential that physicians understand how this complex syndrome presents, and the most appropriate means of investigating and managing it, to avoid unnecessary surgery being performed prior to referral to a specialist center.