Potter Disease, Type I
Patient Information
Characteristics
Background and History
This category of kidney disease was described by pathologist Edith Potter in 1946. Potter disease is only one of a number of types of polycystic kidney disease, so-called because the kidney is filled with cysts.
Clinical Correlations
During gestation, mothers may note little weight gain. Amniotic fluid production is low as is birth weight. Many infants have difficulty breathing from birth and significant numbers of newborns do not live beyond the neonatal period. Urine production is low and tests reveal cysts in the kidneys. The liver may not develop normally either. The face is said to have a characteristic appearance in which the nose is flat, the eyes appear to be far apart and the ears are large and low-set. The neck may be short and skull flattened in the back. The vertebrae are often malformed as well. Congenital heart defects are common.
Genetics
Inheritance
This type of polycystic kidney disease seems to be inherited in an autosomal recessive pattern based on the few reported families in which the parents were related. So far, no responsible gene 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.
Diagnosis and Prognosis
The diagnosis is often made by pediatricians based on the constellation of kidney and morphologic findings. The kidney disease may be unilateral but when both kidneys are severely involved, as many as one-third of infants die before birth. Many others do not survive the newborn period and those that do often have chronic lung and kidney disease.
Web Resources
Printer Friendly Version: Ctrl/Cmd+P