More than 150 People Worldwide
National Organization for Rare Disorders
Summary CLOVES syndrome (CS) is a recently described rare disorder characterized by tissue overgrowth and complex vascular anomalies. CLOVES stands for congenital lipomatous (fatty) overgrowth, vascular malformations, epidermal nevi and scoliosis/skeletal/spinal anomalies. Introduction CLOVES syndrome was described independently by Saap and colleagues in 2007 and Alomari in 2009. A case report by the German physician Hermann Friedberg “gigantism of the right lower limb” published in 1867 is probably the first known written account of CLOVES syndrome.Signs & Symptoms
CLOVES syndrome may affects the soft tissue, blood vessels, bone and internal organs. The manifestations are very variable ranging from mild to severe anomalies. These abnormalities are typically present at birth. The most common features are:
- Fatty masses. Soft fatty masses of variable size are noted at birth and can be located in the back, flanks, axilla, abdomen and buttocks. These masses may affect one or both sides of the body. The skin over the mass is typically covered with a red-pinkish birthmark (capillary malformation or port-wine stain).
- Vascular anomalies: Dilated veins in the chest, upper and lower extremities may cause clot formation and occasionally serious pulmonary embolism (clot travelling from the vein to the lungs). Lymphatic malformations are abnormal, large spaces filled with lymph. These malformations are frequently noted within the fatty masses or inside the abdomen and chest. A small subgroup of patients may suffer from the more aggressive arteriovenous malformation around the area of the spinal cord.
- Abnormal extremities (arms and legs) are common. Large wide hands or feet, large fingers or toes, wide space between digits (sandal gap toe) and uneven size of extremities are common.
- Spinal anomalies include scoliosis (curving of the spine), fatty masses and vessels pushing on the spinal cord and tethered cord (spinal cord fixed by abnormal band).
- Skin birthmarks include port-wine stains, prominent veins, lymphatic vesicles, moles and epidermal nevus (slightly raised areas of skin with light brownish color).
- Kidney anomalies: The size of the kidneys could be asymmetric (one is larger) and may show some abnormal features on imaging studies. Wilms tumor has been noted in a small number of young patients with CLOVES syndrome. This requires screening with serial ultrasound examinations.
Additional findings can occur in CLOVES syndrome including bleeding from the intestine, and asymmetric face and head.
Not all patients with CLOVES syndrome have all these signs, but rather a combination of abnormalities. Some can be subtle and a dedicated physical exam and proper imaging studies are required.