<prompt> All are true about lymphedema exceptPrevalence of 0.1-2Interstitial fluid accumulationSevere Lymphedema if limb volume 40Primary lymphedema sets in by age of 2  <response>: Lymphoedema may be defined as abnormal limb swelling caused by the accumulation of increased amounts of high protein ISF secondary to defective lymphatic drainage in the presence of near normal net capillary filtration. At bih, 1 in 6000 people will develop lymphoedema with an overall prevalence of 0.13-2.The severity of unilateral limb lymphoedema can be classified as:mild: 20 excess limb volume;moderate: 20-40 excess limb volume;severe: 40 excess limb volumeTypes of Primary lymphedemaCongenital onset 2 years old: sporadic; familial Nonne-Milroys diseasePraecox onset 2-35 years old: sporadic; familial Letessier-Meiges diseaseTarda onset after 35 years oldRef: Bailey and love 27e pg: 998 