Which assessment finding would be expected in a neonate with suspected Potter syndrome?

Potter phenotype

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• Exams and Tests
• Outlook (Prognosis)
• References
• Version Info
• Article Sections
• Head and Neck
• Respiratory and Cardiovascular Systems
• Which areas of the neonate are assessed for jaundice?
• When assessing a newborn for early signs of jaundice which technique does the nurse use?
• Which symptom at birth would the nurse identify as likely associated with a congenital cardiac defect?
• Which factor might account for loose stools in a newborn after phototherapy?

Potter syndrome and Potter phenotype refers to a group of findings associated with a lack of amniotic fluid and kidney failure in an unborn infant.

Amniotic fluid not only protects the fetus from injury and temperature changes, it also is circulated by the fetus every 3 hours.

Broad nasal bridge, or widening of the base of the nose, is a relative term. It can be a normal facial feature, but it can also be associated with certain congenital disorders such as basal cell nevus syndrome, or trisomy 8, a chromosome defect.

Causes

In Potter syndrome, the primary problem is kidney failure. The kidneys fail to develop properly as the baby is growing in the womb. The kidneys normally produce the amniotic fluid (as urine).

Potter phenotype refers to a typical facial appearance that occurs in a newborn when there is no amniotic fluid. The lack of amniotic fluid is called oligohydramnios. Without amniotic fluid, the infant is not cushioned from the walls of the uterus. The pressure of the uterine wall leads to an unusual facial appearance, including widely separated eyes.

Potter phenotype may also lead to abnormal limbs, or limbs that are held in abnormal positions or contractures.

Oligohydramnios also stops development of the lungs, so the lungs do not work properly at birth.

Symptoms

Symptoms include:

• Widely separated eyes with epicanthal folds, broad nasal bridge, low set ears, and receding chin
• Absence of urine output
• Difficulty breathing

Exams and Tests

A pregnancy ultrasound may show lack of amniotic fluid, absence of fetal kidneys, or severely abnormal kidneys in the unborn baby.

The following tests may be used to help diagnose the condition in a newborn:

• X-ray of the abdomen
• X-ray of the lungs

Treatment

Resuscitation at delivery may be attempted pending the diagnosis. Treatment will be provided for any urinary outlet obstruction.

Outlook (Prognosis)

This is a very serious condition. Most of the time it is deadly. The short-term outcome depends on the severity of lung involvement. Long-term outcome depends on the severity of kidney involvement.

Prevention

There is no known prevention.

References

Joyce E, Ellis D, Miyashita Y. Nephrology. In: Zitelli BJ, McIntire SC, Nowalk AJ, eds. Zitelli and Davis' Atlas of Pediatric Physical Diagnosis. 7th ed. Philadelphia, PA: Elsevier; 2018:chap 14.

Marcdante KJ, Kliegman RM. Congenital and developmental abnormalities of the urinary tract. In: Marcdante KJ, Kliegman RM, eds. Nelson Essentials of Pediatrics. 8th ed. Philadelphia, PA: Elsevier; 2019:chap 168.

Mitchell AL. Congenital anomalies. In: Martin RJ, Fanaroff AA, Walsh MC, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 30.

Version Info

Last reviewed on: 8/10/2021

Reviewed by: Neil K. Kaneshiro, MD, MHA, Clinical Professor of Pediatrics, University of Washington School of Medicine, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

Article Sections

The routine newborn assessment should include an examination for size, macrocephaly or microcephaly, changes in skin color, signs of birth trauma, malformations, evidence of respiratory distress, level of arousal, posture, tone, presence of spontaneous movements, and symmetry of movements. A newborn with one anatomic malformation should be evaluated for associated anomalies. Total and direct bilirubin levels should be measured in newborns with jaundice, and a complete blood count should be obtained in those with pallor or a ruddy complexion. Neurosurgical consultation is necessary in infants with craniosynostosis accompanied by restricted brain growth or hydrocephalus, cephaloceles, or exophytic scalp nodules. Neck masses can be identified by their location and include vascular malformations, abnormal lymphatic tissue, teratomas, and dermoid cysts. Most facial nerve palsies resolve spontaneously. Conjunctivitis is relatively common in newborns. Infants with chest abnormalities may need to be evaluated for Poland's syndrome or Turner's syndrome. Murmurs in the immediate newborn period are usually innocent and represent a transition from fetal to neonatal circulation. Because cyanosis is primarily secondary to respiratory or cardiac causes, affected newborns should be evaluated expeditiously, with the involvement of a cardiologist or neonatologist.

A careful examination at delivery helps the physician detect anomalies, birth injuries, and cardiorespiratory disorders that may compromise a newborn's successful adaptation to extrauterine life. A detailed examination should also be performed after the newborn has completed the transition from fetal to neonatal life. The examination may begin with an evaluation of neonatal size (Table 1). The presence of one anatomic malformation should prompt an evaluation for associated anomalies. Part I of this two-part article focuses on anomalies and disorders involving the skin, head and neck, chest, and respiratory and cardiovascular systems.

Erythema toxicum neonatorum, transient neonatal pustular melanosis, sucking blister, miliaria, and mongolian spots are among the many benign skin conditions that can occur in newborns. Total and direct bilirubin levels should be measured in newborns with jaundice, and various causes for this condition should be considered (Table 2). The American Academy of Pediatrics1 has published guidelines on the management of hyperbilirubinemia in healthy term infants. A complete blood count should be obtained in newborns with pallor or a ruddy complexion.

The diagnosis and treatment of cutaneous vascular lesions in newborns are reviewed elsewhere.2

Head and Neck

Head circumference and fontanelle size can indicate a congenital disorder or head trauma (Tables 3 and 43). Craniosynostosis, or premature fusion of cranial sutures, results in growth restriction perpendicular to the affected suture(s) and compensatory overgrowth in unrestricted regions4 (Figure 1). This anomaly may suggest a genetic disorder such as Apert's syndrome or Crouzon's disease. If the synostosis is accompanied by restricted brain growth or hydrocephalus, neurosurgical intervention is necessary.

Large meningoceles or encephaloceles are usually diagnosed prenatally or at birth. Smaller defects may be mistaken for cutaneous lesions such as hemangiomas or dermoid cysts. Congenital exophytic scalp nodules should always be evaluated further, because 20 to 37 percent of these lesions connect to the underlying central nervous system.5 Cutaneous signs of cranial dysraphism include the “hair collar sign” (darker, coarser hair encircling the scalp nodule), vascular malformations, and cutaneous dimples and sinuses. Cephaloceles and exophytic scalp nodules should be assessed by magnetic resonance imaging (MRI), and a neurosurgical consultation should be obtained.5

The most common neck masses are vascular malformations, abnormal lymphatic tissue, teratomas, and dermoid cysts. Neck masses can be identified based on their location (Figure 2).6 Thyroglossal duct cysts, one of the most frequent congenital anomalies of the neck, are typically midline and inferior to the hyoid bone. Surgical consultation is required in newborns with thyroglossal duct cysts.

Clavicular fractures are the most common broken bones in newborns, especially large neonates. Of these, greenstick fractures are the most frequent and are usually asymptomatic. Newborns may present with decreased or absent movement and pain or tenderness on movement of the arm on the affected side, deformity and discoloration over the fracture site, and crepitus or irregularity along the clavicle. Treatment is directed at minimizing the newborn's pain or discomfort. If the newborn with clavicular fracture is in pain, the affected arm should be immobilized, with the arm abducted more than 60 degrees and the elbow flexed more than 90 degrees.3

FACE

Facial nerve paralysis is caused by compression of the nerve against the sacral promontory or by trauma resulting from the use of forceps during delivery. Paralysis is usually apparent on the first or second day of life. The nasolabial fold on the paralyzed side is obliterated, and the corner of the mouth droops; with crying, the mouth is drawn to the normal side4 (Figure 3). With peripheral facial nerve paresis, the forehead and eyes may be affected.

Most facial nerve palsies resolve spontaneously within days, although full recovery may require weeks to months. A persistently open eye should be protected from corneal drying. Electrodiagnostic testing may be necessary if no improvement occurs within seven to 10 days; rarely, surgical intervention is needed.3 Congenital absence or hypoplasia of the depressor anguli oris muscle may simulate facial palsy.

Erupted teeth are present in approximately one of 2,000 newborns.7 Although natal teeth are frequently found in normal infants, they are more often present in newborns with cleft palate. They are also commonly associated with Ellis–van Creveld syndrome, Hallermann-Streiff syndrome, and pachyonychia congenita syndrome. Most erupted teeth, particularly if loose, require removal.

Isolated cleft palate differs genetically from cleft lip. Mild forms of cleft palate include sub-mucosal clefts, pharyngeal incompetence and bifid uvula. Cleft lip, with or without cleft palate, is found in newborns with trisomy 13 syndrome, holoprosencephaly (median cleft lip), and amnion rupture sequence. Newborns with a cleft lip or palate require genetic evaluation and plastic surgery. Because of feeding difficulties, the mothers of these infants may benefit from lactation consultation and occupational therapy.

EYES

Marked lid edema often results in eversion of the upper lid when force is applied to open the eye. Examination should be postponed until the edema resolves. Subconjunctival hemorrhages, which are common after vaginal delivery, usually do not represent ocular trauma. Conjunctivitis is relatively common in newborns (Table 5).8,9

Coloboma (absence or defect of some ocular tissue) may involve the eyelid margin, as in Treacher Collins syndrome, or the iris and retina, as in the CHARGE association (syndrome of coloboma, heart disease, choanal atresia, postnatal growth retardation, genital hypoplasia and ear anomalies). Aniridia (absence of the iris) is usually bilateral and is almost always associated with poor vision and nystagmus. Newborns with aniridia or coloboma should have a formal eye examination.

The red reflex normally shows no dullness or irregularities. A white pupil (cat's eye reflex) denotes an abnormality of the lens, vitreous, or fundus. One of the most common presenting signs of a cataract is a white pupillary reflex. Congenital cataract is present in 0.4 percent of newborns. These infants should be tested for TORCH (toxoplasmosis, other viruses, rubella, cytomegaloviruses, herpes [simplex] viruses) infections. Newborns with monocular congenital or dense cataracts are at risk for developing deprivation amblyopia. Newborns with cataracts should be evaluated by an ophthalmologist.10

Congenital glaucoma, while uncommon, may present at birth. More often, signs of glaucoma develop during the first several weeks or months of life and include corneal cloudiness and enlargement, tearing, blepharospasm, and photophobia. Corneal edema can also occur secondary to the malpositioning of forceps during delivery. Prompt referral to an ophthalmologist is indicated.11

Chest

Although pectus carinatum and pectus excavatum are of concern to parents, these physical anomalies are rarely of clinical significance. Unilateral absence or hypoplasia of the pectoralis major muscle suggests the diagnosis of Poland's syndrome (sometimes called Poland's sequence). Common associated findings in this syndrome include rib defects, hypoplasia of the upper extremities, and syndactyly. Occasionally, more severe limb reduction deformities, hemivertebrae, renal anomalies, and dextrocardia may be present.

Widely spaced nipples, excessive nuchal skin, and lymphedema are findings associated with Turner's syndrome. The evaluation of newborns suspected of having this syndrome should include chromosomal analysis, echocardiography to detect cardiac lesions, and a genetic consultation.

A small thorax suggests pulmonary hypoplasia. A bell-shaped thorax is often present in newborns with neurologic abnormalities or some dwarfing syndromes.

Respiratory and Cardiovascular Systems

Newborns with choanal atresia present with cyanosis that is relieved by crying. The diagnosis is usually established by the inability to pass a catheter through the nostril(s). Unilateral choanal atresia may remain undiagnosed for years. Infants and children with this congenital anomaly may present with mucus or foul-smelling secretions from the affected nares and respiratory distress associated with upper respiratory infection.

Newborns with significant cyanosis should be evaluated expeditiously. Depending on the clinical findings, consultation with a neonatologist may be required. Respiratory disease is more likely in newborns who are tachypneic and using accessory muscles of respiration. Newborns with heart disease generally breathe normally, except for mild tachypnea or hyperpnea. The differential diagnosis and evaluation of cyanosis in infants are presented in Table 6.

The normal heart rate in newborns is 120 to 160 beats per minute. Some term newborns have a resting heart rate below 90 beats per minute. If the heart rate does not increase appropriately with stimulation, serum electrolyte levels should be checked, and an electrocardiogram should be obtained to rule out heart block.

Diminished pulses in all extremities indicate poor cardiac output or peripheral vasoconstriction. Absent or diminished femoral pulses suggest the presence of ductaldependent cardiac lesions (e.g., coarctation of the aorta). Although hypertension is uncommon in newborns, it is rarely idiopathic. An approach to determining the cause of neonatal hypertension is presented in Figure 4.12

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Palpation and auscultation may reveal a shift in the position of the heart from normal, as occurs in dextrocardia. In newborns, a murmur does not always signify the presence of heart disease, nor does the absence of a murmur provide reassurance of normalcy. Newborns with relatively benign lesions, such as small ventricular septal defects, often have the loudest murmurs, whereas newborns withsevere heart disease may have no murmurs. The most commonly auscultated murmurs in the immediate newborn period are flow murmurs that represent a transition from fetal to neonatal circulation (e.g., tricuspid regurgitation, patent ductus arteriosus). Further evaluation is required if a murmur persists beyond several weeks in a healthy newborn or if a murmur is present in a critically ill infant.

Which areas of the neonate are assessed for jaundice?

When assessing a newborn for early signs of jaundice which technique does the nurse use?

Which symptom at birth would the nurse identify as likely associated with a congenital cardiac defect?

Which factor might account for loose stools in a newborn after phototherapy?