淋巴水肿是由于淋巴系统无法输送淋巴液造成的。在淋巴水肿出现明显临床表现之前,大约有80%的淋巴引流肯定是非功能性的。[3]Slavin SA, Greene AK, Borud LJ. Lymphedema. In: Weinzweig J, ed. Plastic surgery secrets plus. 2nd ed. Philadelphia, PA: Mosby; 2009.异常淋巴回流可能是由淋巴管发育不全、阻塞或纤维化造成的。全球90%以上病例的原因是癌症治疗(特别是乳腺癌治疗)、恶性肿瘤、线虫感染(丝虫病)和创伤。[3]Slavin SA, Greene AK, Borud LJ. Lymphedema. In: Weinzweig J, ed. Plastic surgery secrets plus. 2nd ed. Philadelphia, PA: Mosby; 2009.
淋巴结清除术、放射疗法或肿瘤浸润都可损伤淋巴系统(例如,骨盆腔肿瘤或淋巴结清除术可导致下肢或生殖器淋巴水肿)。[10]McDougal WS. Lymphedema of the external genitalia. J Urol. 2003;170:711-716.http://www.ncbi.nlm.nih.gov/pubmed/12913680?tool=bestpractice.com寄生线虫,如班氏丝虫和马来丝虫,由蚊虫媒介传播,可通过直接阻塞淋巴通道或区域性炎症引发淋巴丝虫病。[11]Palumbo E. Filariasis: diagnosis, treatment and prevention. Acta Biomed. 2008;79:106-109.http://www.ncbi.nlm.nih.gov/pubmed/18788504?tool=bestpractice.com在蚊虫疫区,有多达1.2亿人口由于线虫感染发展为淋巴水肿。[11]Palumbo E. Filariasis: diagnosis, treatment and prevention. Acta Biomed. 2008;79:106-109.http://www.ncbi.nlm.nih.gov/pubmed/18788504?tool=bestpractice.com[12]Wynd S, Melrose WD, Durrheim DN, et al. Understanding the community impact of lymphatic filariasis: a review of the sociocultural literature. Bull World Health Organ. 2007;85:493-498.http://www.scielosp.org/scielo.php?script=sci_arttext&pid=S0042-96862007000600017&lng=en&nrm=iso&tlng=enhttp://www.ncbi.nlm.nih.gov/pubmed/17639248?tool=bestpractice.com严重穿透伤,尤其是在腋窝或腹股沟,可能会损伤淋巴系统,随之引发淋巴水肿。此外,曲线疤痕可能滞留淋巴液,因而产生一个凸起、肿胀的区域和瘢痕性淋巴水肿。[13]Warren AG, Slavin SA. Scar lymphedema: fact or fiction? Ann Plast Surg. 2007;59:41-45.http://www.ncbi.nlm.nih.gov/pubmed/17589258?tool=bestpractice.com
原发性淋巴水肿通常是由于淋巴系统发育不全造成的,在淋巴水肿患者中的占比可能还不到1%。[3]Slavin SA, Greene AK, Borud LJ. Lymphedema. In: Weinzweig J, ed. Plastic surgery secrets plus. 2nd ed. Philadelphia, PA: Mosby; 2009.[6]Smeltzer DM, Stickler GB, Schirger A. Primary lymphedema in children and adolescents: a follow-up study and review. Pediatrics. 1985;76:206-218.http://www.ncbi.nlm.nih.gov/pubmed/4022694?tool=bestpractice.com大多数病例是散发性的;但大约有10%-15%的患者具有家族性或综合征性淋巴水肿。[1]Schook CC, Mulliken JB, Fishman SJ, et al. Primary lymphedema: clinical features and management in 138 pediatric patients. Plast Reconstr Surg. 2011;127:2419-2431.http://www.ncbi.nlm.nih.gov/pubmed/21617474?tool=bestpractice.com在某些淋巴水肿相关综合征中已鉴定出致病突变:Milroy病(VEGFR3)、淋巴水肿—双行睫综合征(FOXC2)、稀毛症—淋巴水肿—毛细血管扩张(SOX18)和Hennekam综合征(CCBE1)。[14]Irrthum A, Karkkainen MJ, Devriendt K, et al. Congenital hereditary lymphedema caused by a mutation that inactivates VEGFR3 tyrosine kinase. Am J Hum Genet. 2000;67:295-301.http://www.cell.com/ajhg/fulltext/S0002-9297(07)62641-Xhttp://www.ncbi.nlm.nih.gov/pubmed/10856194?tool=bestpractice.com[15]Irrthum A, Devriendt K, Chitayat D, et al. Mutations in the transcription factor gene SOX18 underlie recessive and dominant forms of hypotrichosis-lymphedema-telangiectasia. Am J Hum Genet. 2003;72:1470-1478.http://www.cell.com/ajhg/fulltext/S0002-9297(07)60446-7http://www.ncbi.nlm.nih.gov/pubmed/12740761?tool=bestpractice.com[16]Finegold DN, Kimak MA, Lawrence EC, et al. Truncating mutations in FOXC2 cause multiple lymphedema syndromes. Hum Mol Genet. 2001;10:1185-1189.http://hmg.oxfordjournals.org/content/10/11/1185.longhttp://www.ncbi.nlm.nih.gov/pubmed/11371511?tool=bestpractice.com[17]Boon LM, Ballieux F, Vikkula M. Pathogenesis of vascular anomalies. Clin Plast Surg. 2011;38:7-19.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3031181/http://www.ncbi.nlm.nih.gov/pubmed/21095468?tool=bestpractice.com[18]Alders M, Hogan BM, Gjini E, et al. Mutations in CCBE1 cause generalized lymph vessel dysplasia in humans. Nat Genet. 2009;41:1272-1274.http://www.ncbi.nlm.nih.gov/pubmed/19935664?tool=bestpractice.com
常染色体显性遗传最常见(例如,Milroy病、Meige病、淋巴水肿—双行睫综合征),[3]Slavin SA, Greene AK, Borud LJ. Lymphedema. In: Weinzweig J, ed. Plastic surgery secrets plus. 2nd ed. Philadelphia, PA: Mosby; 2009.[6]Smeltzer DM, Stickler GB, Schirger A. Primary lymphedema in children and adolescents: a follow-up study and review. Pediatrics. 1985;76:206-218.http://www.ncbi.nlm.nih.gov/pubmed/4022694?tool=bestpractice.com但也会发生常染色体隐性遗传(例如,稀毛症、淋巴水肿—毛细血管扩张、Hennekam综合征)。[17]Boon LM, Ballieux F, Vikkula M. Pathogenesis of vascular anomalies. Clin Plast Surg. 2011;38:7-19.http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3031181/http://www.ncbi.nlm.nih.gov/pubmed/21095468?tool=bestpractice.com[19]Ghalamkarpour A, Holnthoner W, Saharinen P, et al. Recessive primary congenital lymphoedema caused by a VEGFR3 mutation. J Med Genet. 2009;46:399-404.http://www.ncbi.nlm.nih.gov/pubmed/19289394?tool=bestpractice.com其他几种情况(例如,Noonan综合征、Turner综合征)也会增加原发性淋巴水肿的风险。[20]Brice G, Child AH, Evans A, et al. Milroy disease and the VEGFR-3 mutation phenotype. J Med Genet. 2005;42:98-102.http://jmg.bmj.com/content/42/2/98.longhttp://www.ncbi.nlm.nih.gov/pubmed/15689446?tool=bestpractice.com