OMIM ID:
Potter Disease, Type I
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
As part of the facial morphology said to be characteristic of Potter disease, there is usually hypertelorism, telecanthus and epicanthal folds. Cataracts and angiomas of the optic disc area have also been described.
Systemic Features
Polycystic kidney disease and hepatic system anomalies are major features of Potter disease. Pulmonary hypoplasia with neonatal respiratory distress, however, is often the most immediate cause of death in most infants. Antenatal oligohydramnios and low birth weight are commonly present. As many as 33% of fetuses die in utero, often the result of bilateral renal agenesis. Infants that survive can have chronic lung disease and renal dysfunction. Congenital heart malformations are common, including septal defects, tetralogy of Fallot and patent ductus arteriosis. Vertebrae may have a ‘butterfly’ shape but other skeletal findings include hemivertebrae and sacral agenesis. The neck has been described as short and the skull is brachycephalic.
The facial appearance, known as Potter facies, is said to be characteristic and may be helpful in distinguishing this type of polycystic kidney disease. In addition to the ocular findings, the nares are often anteverted, and the external ears are large and often posteriorly rotated.
Genetics
Inheritance
The uniqueness of this syndrome remains to be established. There are several polycystic kidney disorders which have a monogenic basis. These often have overlapping renal features with the condition described here but lack the facial features said to be characteristic of Potter type I disease. Autosomal recessive inheritance has been suggested on the basis of several reported families with affected sibs from consanguineous parents but so far no gene locus or mutation has been identified.
Pedigree
Autosomal recessive
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.
In order for autosomal recessive disorders to be expressed, offspring generally must inherit two mutations, one from each carrier parent. Carriers with only one mutation, such as the parents, do not have clinical disease. Note that carrier parents can expect that 1 in 4 children (25%) will inherit both mutations and have the disorder, 2 in 4 children (50%) will be carriers like their parents, while 1 in 4 children (25%) inherit neither mutation.