The first signs of Potter syndrome are evident in the womb before one month of fetal development. At this stage, the ureteral bud, which forms the kidneys, fails to develop. The urine that is produced by the kidneys during pregnancy creates the amniotic fluid (a yellowish liquid that surrounds the unborn baby during pregnancy). If the uteral bud fails to develop, like in Potter syndrome, little amniotic fluid is produced as a result. The production of amniotic fluid during pregnancy is vital to the development of the baby's lungs. In Potter syndrome, the lungs of the baby do not develop fully because of a lack of amniotic fluid (this is known as oligohydramnios). During pregnancy, babies may appear to have normal weight and size for their age because the placenta performs the filtering work of the kidneys. However, babies die either during birth or very shortly thereafter mainly because of pulmonary hypoplasia (underdevelopment of the lungs).
Potter syndrome was first described by Dr Edith Potter in 1946. It is an extremely rare condition involving a total absence (agenesis) or severe malformation (dysgenesis or dysplasia) of both infant kidneys. The normal function of the kidneys is to filter waste products from the blood, eliminating them as urine. Absence of one kidney (unilateral) is compatible with life whereas absence of both kidneys (bilateral) is fatal.
Medical text written August 2003 by Contact a Family. Approved August 2003 by the medical advisor in paediatric nephrology to the National Kidney Research Fund UK. Last updated in March 2010 by Dr Jane Tizard, Consultant Paediatric Nephrologist, Department of Paediatric Nephrology, Bristol Royal Hospital for Children, Bristol, UK.
What are the symptoms?
How is it treated?
Potter syndrome occurs twice as frequently in males compared with with females. There is no known treatment for classical Potter syndrome and it is always fatal due to the underdevelopment of the baby's lungs. In some Potter-like cases where the kidneys are present but are severely malformed, the kidneys may have produced enough urine during pregnancy, and therefore sufficient amniotic fluid, for the lungs to develop enough for the baby to survive. In this situation, babies may survive if kidney function can be supported with a form of dialysis, however, this is technically very challenging.
Inheritance patterns and prenatal diagnosis
In most cases, Potter syndrome occurs sporadically in which case it is not likely to happen again in the same family. In some cases, Potter syndrome may be inherited as an autosomal dominant trait. Potter syndrome is more common in infants born of a parent who has a kidney malformation, particularly unilateral renal agenesis (absence of one kidney). Genetic counselling is recommended after the birth of a baby with Potter syndrome.
Potter syndrome may be identified on ultrasound examination in subsequent pregnancies. As Potter syndrome is frequently associated with clinically silent anomalies of the kidneys, ultrasound examination of the kidneys and urinary tract would be recommended for the parents in the first instance.