What is bilateral infantile polycystic kidney disease?
Asst. Professor of Medicine,
Overton Brooks VA Medical Centre,
USA
Q: My friend is pregnant and is due anytime now. When she was 8 months pregnant, the doctor had taken a scan and then advised her to go for an MRI scan. Her MRI Scan result shows that the foetus has Bilateral infantile polycystic kidney disease. How dangerous is this disease? What are the symptoms? How does it occur in an unborn baby? Now she has been admitted to the hospital for bedrest as she has high BP (140/90). This is her second baby. Her first delivery was a normal delivery. Does high BP mean that she has to undergo C-section?
A:Infantile polycystic kidney disease (AKA: Autosomal Recessive Polycystic Kidney Disease or ARPKD) is a rare disease of infants or neonates whose incidence is estimated to be from 1:10,000 to 1:40,000. This is a genetic disorder inherited as a recessive condition, i.e. two copies of the mistaken gene are required to cause the problems; having just one mistaken copy makes you a carrier and is usually asymptomatic. Thus both parents have to be carriers, and any brother or sister of an affected child has a 1:4 chance of having it. Both parents are carriers without symptoms or signs. ARPKD is characterized by presence of small cysts on the tubules of the kidney. The greater number of tubules involved, the more likelihood of kidney damage. The liver is often affected which may mean a transplant of both organs may be needed. Fetuses with ARPKD and severe impairment of renal function have decreased fetal urine output and oligohydramnios. The main complication in new born babies is pulmonary (lung) distress. Mechanical ventilation may be needed. Many of these infants may die from pulmonary complications shortly after birth. The rate at which kidney function is lost varies widely, but the majority of babies who survive the first month of life do not develop severe kidney failure until later childhood or adolescence. In those with less severe disease who survive the neonatal period, renal insufficiency or end-stage renal failure may develop. However, the age at which this occurs is variable and depends on the degree of involvement. However, if baby survives beyond infancy, transplantation of kidney and/or liver may perhaps be the best treatment option. As far as high blood pressure in mother is concerned, she perhaps has Pregnancy Induced hypertension (PIH) and has been appropriately advised bed rest. Unless she was hypertensive prior to this pregnancy, her BP is expected to return normal levels following the completion of pregnancy. Since she is close to term and can deliver anytime, she may not have to undergo C-section unless there are other indications for this surgery. The couple should undergo appropriate genetic counselling before they plan their next pregnancy and expectant mother should be advised of high risk of PIH during subsequent pregnancies.