A 1-day-old girl is evaluated in the newborn nursery due to swollen hands and feet. She was born via vaginal delivery at 38 weeks gestation to a 28-year-old mother. Birth weight was 2.8 kg (6 lb 3 oz). There was no history of fetal distress, delayed crying, lethargy, or feeding difficulty. There is no family history of recurrent miscarriages, infantile deaths, or genetic diseases. Vital signs are normal. She is active, with intact suck, Moro, and grasp reflexes. There is bilateral nonpitting edema of the hands and feet extending up to the elbows and ankles, respectively. The neck is short with loose skin. Nails are dysplastic. What is the most appropriate next step in diagnosis?
Turner syndrome | |
Etiology |
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Presentation |
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Diagnosis & management |
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This newborn with nonpitting carpal and pedal edema has congenital lymphedema, a condition caused by dysgenesis of the lymphatic system. In an infant girl, congenital lymphedema—particularly when associated with dysmorphic features—should raise suspicion for Turner syndrome, a genetic disorder associated with hypoplasia of lymphatic vessels, causing poor lymph absorption. Lymphatic obstruction leads to fluid accumulation in the interstitial space of the hands and feet, as seen in this patient; the edema is nonpitting because of the high protein content of the interstitial fluid.
In addition to edema of the hands and feet, other characteristic dysmorphic features of Turner syndrome are related to underlying lymphedema, including:
A webbed neck (ie, short neck with loose skin as in this patient) with low hairline from extravasation of cervical lymph
Cystic hygroma from severe obstruction the lymphatic vessels of the neck. Hydrops fetalis can occur with excessive fluid accumulation.
Dysplastic nails, as seen in this patient, from in utero hand/foot swelling
Diagnosis of Turner syndrome is with a karyotype, or blood chromosome analysis, identifying a complete or partial deletion of an X chromosome. Once the diagnosis is confirmed, screening for other comorbidities is required, including renal ultrasound for horseshoe kidney as well as echocardiogram for aortic coarctation and bicuspid aortic valve.
Treatment of congenital lymphedema is supportive (eg, compression bandages, skin care), and symptoms generally improve in early childhood.
(Choices B and C) Cerebral edema can be evaluated with dilated funduscopic examination (ie, papilledema) and MRI of the brain, but these studies are not helpful in evaluating congenital lymphedema. In addition, intracranial abnormalities do not occur with Turner syndrome.
(Choice D) Dysmorphic features are seen in a form of congenital pseudohypoparathyroidism (ie, end-organ unresponsiveness to parathyroid hormone) known as Albright hereditary osteodystrophy; however, these include short metacarpal bones, short stature, and round facies (vs webbed neck, dysplastic nails). Hypoparathyroidism in very rare cases can be associated with congenital lymphedema. However, the priority in this patient is to evaluate for Turner syndrome, a common genetic cause of lymphedema.
(Choice E) Patients with Turner syndrome often have renal anomalies (eg, horseshoe kidney), which can be associated with hydronephrosis or obstruction. Vesicoureteral reflux or obstructive uropathy (which voiding cystourethrography can diagnose) may lead to renal failure and subsequent peripheral edema. However, in contrast to this patient, edema associated with kidney injury is pitting (due to low protein concentration in interstitial fluid).
Educational objective:
Congenital lymphedema occurs due to dysgenesis of the lymphatic system and presents in infants with nonpitting carpal and pedal edema. Turner syndrome should be suspected in an infant girl with congenital lymphedema, webbed neck, and dysplastic nails; loss of an X chromosome on karyotype is diagnostic.