To date, only one gene, short-stature homeobox gene ( SHOX), has been confirmed to cause phenotypic features of Turner syndrome, specifically short stature and skeletal abnormalities. ![]() Identification of causative genes for the lymphatic phenotype in Turner syndrome has proven difficult. 16 One lymphoscintigraphic study of Turner syndrome patients has demonstrated various lymphatic pathological features and identified aplasia, hypoplasia and hyperplasia of the peripheral lymphatics in Turner syndrome patients. Swelling resolved in 19% (87% of these by 2 years), improved in 31%, worsened in 10% and was unchanged in 40%. 2, 14, 15 One key study, a retrospective questionnaire study focusing on the progression of lymphoedema in 42 Turner syndrome patients, found that 76% patients had swelling at birth and 55% had hand and feet swelling. The literature that is available reports that lymphoedema is most commonly found in Turner syndrome patients with a non-mosaic 45,X karyotype and usually resolves by 2 years of age, although it can persist throughout life and recur. There is a lack of detailed medical literature regarding the lymphatic phenotype of Turner syndrome. Prenatal lethality in Turner syndrome may also be due to an underlying lymphatic abnormality, resulting in fluid imbalance and hydrops fetalis. In utero facial oedema manifests as epicanthic folds and peripheral lymphoedema manifests as swollen hands and feet, deep digital skin fold creases and small dysplastic toenails. 2 Cervical lymphatic system distension manifests as a webbed neck and a low posterior hairline 2 (observable as increased nuchal translucency on ultrasound scanning (USS) at 10–14 weeks 8, 12). 2, 8, 12 Many phenotypic features of Turner syndrome are believed to result from in utero oedema. 2 Lymphoedema is thought to result from lymphatic hypoplasia or aplasia of the lymphatic tracts, which results in stasis of lymph fluid and swelling. ![]() ![]() 2 Swollen hands and feet in a female neonate always suggest a diagnosis of Turner syndrome. This facilitates an early diagnosis in an approximately one-third of patients. Lymphoedema of the hands and feet is thought to be present in >60% of infants with Turner syndrome. 10 Lymphoscintigraphy (imaging of peripheral lymph drainage through interstitial injection of a radiolabelled colloid and gamma camera detection) is the gold-standard investigation for lymphoedema, but it is not routinely performed in all centres. 9 Like Turner syndrome, Milroy disease may present with congenital pedal oedema however, hand swelling is rarely noted in Milroy disease and this condition affects males and females equally. Primary lymphoedema has many genetic causes. A compromised lymphatic system results in lymphatic insufficiency, with swelling and fluid retention in one or more limbs or body segment (eg, head, neck or genitalia) or systemically with gut, pericardial or respiratory involvement. This is due to a failure of the lymph-conducting system. ![]() It is characterised by the accumulation of lymph and other elements (commonly proteins) in the interstitial spaces. Lymphoedema is a chronic, debilitating and incurable condition. The lymphoscintigraphy results suggest that the lymphatic phenotype of Turner syndrome may be due to a failure of initial lymphatic (capillary) function. There was only one case of suspected systemic involvement (intestinal lymphangiectasia). The swelling was confined to the legs and hands with no facial or genital swelling. The majority of patients presented at birth with four-limb lymphoedema, which often resolved in early childhood, but frequently recurred in later life. The aim of this study was to analyse the medical records of a cohort of 19 Turner syndrome patients attending three specialist primary lymphoedema clinics, to elucidate the key features of the lymphatic phenotype and provide vital insights into its diagnosis, natural history and management. Congenital lymphoedema of the hands, feet and neck region (present in over 60% of patients) is a common and key diagnostic indicator, although is poorly described in the literature. Turner syndrome is a complex disorder caused by an absent or abnormal sex chromosome.
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