Sunday, December 19, 2010

What is Potters?

Potter Sequence
Philippe Jeanty, MD, PhD & Sandra R Silva, MD

 
Several entities use the eponym Potter:
1) Potter syndrome, now renamed either oligohydramnios sequence or bilateral renal agenesis (BRA)
depending on whether the cause of the syndrome (BRA) or the mechanism is referred to.

2) Potter syndrome Type I is now referred to as Autosomal recessive polycystic kidney disease
3) Potter syndrome Type II is now referred to as Renal dysplasia
4) Potter syndrome Type III is now referred to as Autosomal dominant polycystic kidney disease


Our son, Christian died from Type II, Renal dysplasia.


WHAT IS POTTERS SYNDROME?
 Potters Syndrome is the term used to describe the total absence or malformation of infant kidneys. The condition gets it name from Edith Potter who first described the condition in 1946 at the Chicago Lying-In Hospital in Chicago. Prior to this there had been several isolated studies done on infants with the condition, some even date back as far as the sixteen hundreds but up until this study it was presumed that the condition was extremely rare. Dr. Potters investigation concentrated only on total Renal Agenesis (absent kidneys) but since then the name has been extended to any condition where the kidneys fail to develop fully.

WHAT IS A SYNDROME?
 A syndrome is a collection of associated problems, which relate to one primary problem. In simple terms with Potters Syndrome the main problem is that the kidneys are missing but because of this other problems arise. The kidneys cannot produce the fluid to develop the lungs so therefore the infant’s lungs are underdeveloped as a result. Also related to the lack of fluid are the physical features of Potters Syndrome. The infant is so tightly packed in the womb that the limbs may not form properly and the face may show certain features such as a flattened nose and chin etc. All of the above go to make up a syndrome which are directly connected to the one major problem, which is the absence or malformation of the kidneys.


WHAT DID DR. POTTERS STUDY SHOW?
The first study was carried out on 20 infants who had died over a ten-year period. In the group there were 17 males and 3 females babies. Of the 19 available maternal histories the mother’s ages ranged from 18 to 39 years giving an average age of 24 years. Two of these women had had previous abortions, only two had more than two previous pregnancies one of whom had 11 children. Nineteen of the mothers were white and one was Negro. There was therefore one common link between the mothers with regard to age, race or number of pregnancies. 

 She also noted that these babies were more likely to be born live rather than stillborn. In the group fetal death occurred prior to labour in one infant, during labour in six and after birth in thirteen. The length of life varied from 25 minutes to 11 hours 15 minutes giving an average life span of 1 hour 38 minutes.
 Of the 16 babies where the gestation of pregnancy had been record the number of weeks varied from 26 weeks to 40 weeks giving an average delivery time of about 32.5 weeks.
 Dr. Potter was unable to establish the amount of amniotic fluid present with each baby and therefore was unable to establish the important link between the kidneys and the production of the fluid. This was only discovered and confirmed later. The cause of the death was mainly associated to the malformation of the lungs. There children also showed similar facial features such as the wide set eyes, a slightly compressed nose, low set flat ears and also a compression of the chin. Other physical features were clubbed feet and some with club hands. With the female babies it was noted that their genitalia were extremely under developed where as with males the development for the most part had been perfectly normal.

SUMMARY: Dr. Potter concluded that the incidence of this condition was somewhere between 4 and 7 deaths per thousand deaths in newborn infant. She also noted that there was no relation to maternal age or to method of delivery or to complication during pregnancy. The infants were predominately male. The lungs of the infants were all severely underdeveloped or hypoplastic and that all the infants showed characteristic facial expressions. Prior to post mortem examination only 8 of the infants were believed to have died because of malformations.




  WHAT DO WE NOW KNOW ABOUT POTTERS SYNDROME?
OCCURRENCE RATE: The incidence of Potters Syndrome is said to be somewhere between 1 in 2000 and 1 and 5000 the average would suggest to be on occurrence rate of approximately 1 in 4000 births.
SEX LINKAGE: Potters Syndrome is predominately a male condition with an occurrence rate of approximately 65% - 80% male babies.
TIME FACTOR: complete Renal Agenesis (or absence of kidneys) must occur before 31 days of fetal development.
CAUSE OF DEATH: The primary cause of infant death is respiratory insufficiency. The fetal kidneys are responsible for the production of the amniotic fluid in the womb. The baby then inhales the fluid into its lungs which in turn causes the lungs to grow.  When the kidneys are absent or not working the vital fluid is not produced and therefore the lungs cannot develop properly and therefore when the baby is born it is unable to breath properly.


ABSENT KIDNEYS: These infants could for up to three or four days with absent or redundant kidneys if the lungs had any other way to develop but because this is not possible the maximum life span for a baby with renal agenesis would seem to be about 12 hours. Where there is some kidney development with a little kidney function the life span could be slightly longer but the child would probably need the aid of a respirator and probably dialysis.

CHRISTIAN DANIEL, my glory baby

WHY DO POTTERS SYNDROME BABIES SHOW SIMILAR PHYSICAL FEATURES?
 When the amniotic fluid is missing the baby lives in a very tightly packed enviroment and therefore will demonstrate very compressed features. Normally the baby is surrounded by the fluid, which allows freedom of movement, and of growth. It helps in the development of the babies muscular and skeletal system. Inhaling the fluid is also vital to the development of the baby’s lungs. The fluid prevents fetal parts growing unevenly and being pressed against the wall of the uterus or womb. With Potters Syndrome the babies face and head will be squashed in the womb and thus lead to the very flat, low-set ears. The nose and chin will also show compression and the nose can sometimes is described as beaked. The muscles will also be under developed as the baby will not have much room for exercise and the feet maybe turned- in otherwise described as clubfeet.  The baby may also have underdevelopment of the hands, which can be described as club-hands.

HOW CAN THE BABY SURVIVE IN THE WOMB WITH POTTERS SYNDROME?
 In the womb the baby’s life is dependent on the functions of the placenta. The placenta acts like a life-support system and filters products and food from the mother to the baby and then back out into the mothers system for disposal. The amniotic fluid, which is normally a straw colored and clear substance, consists of 99% water with small amounts of protein, glucose, and salt and also contains shed cells from the baby. The baby’s urine is mostly water because the mother’s kidneys are functioning via the placenta for the baby disposing of any waste products. Therefore the baby can survive without its kidneys as long as the placenta is functioning normally. The problems for the baby will more than likely only show after birth.

WHAT IS THE RISK OF A REOCCURANCE OF THE POTTERS SYNDROME?
 In the vast majority of cases this is an isolated abnormality and in this respect it is unlikely to recur in the same family. Statistically however once you have had one Potters Syndrome baby the risk of a reoccurrence of some kind of kidney defect is put at about 3%. In a few cases there maybe an abnormality of one kidney from either parent in which case the risk of having Potters Syndrome again may be up to 10%. Rarer again is when there is a genetic link to the syndrome when the risk maybe as high as 1 in 4.
Thankfully the bulk of cases of Potters Syndrome has no parental link and therefore is unlikely to ever happen again. The most difficult issue to deal with is that with these cases there is no explanation as to why it occurred in the first place. It has not yet been discovered just what is responsible for this syndrome. It could be related to chromosome activity or D.N.A. but why it is just the kidneys which do not grow or which malforms is anybody’s guess.

2 comments:

  1. I had a baby born with no kidneys over 20 years ago

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  2. THIS IS THE SADDEST PART TO BE TOLD THAT YOUR BABY HAS NOT DEVELOPED LUNGS AND KIDNEYS....WHICH MEANS CERTAIN DEATH...LITTLE ANGELS HAVE TO SUFFER SO EARLY...WHY? IS THERE AN ANSWER?

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