Saving babies from Cholestasis, or Lethal Itching in Pregnancy
Just now I delivered a 37.0 week baby of a mom who had a case of Cholestasis of Pregnancy. It was an elective delivery done at the cusp of term, delivered early, to save the baby. The baby is now in the nursery and in perfectly good health. The mom is recovering in the recovery room and seems fine. Her cholestasis will resolve in the next few days and she will be completely fine. She has been very very itchy.
Cholestasis of Pregnancy is a very interesting story. What happens is that the bile flow through the maternal liver gets clogged up. Bile is a human waste product that needs to be pumped out of the blood by the liver, into the intestines through the gallbladder, and therefore out of the body. Bile is yellow to brown, and is the end result of the metabolism of recycling old cells of the body. Bile has no use to humans, and it's presence in excessive quantities causes a ton of trouble. In high quantities bile in the blood makes the patient turn a shade of yellow or gold called "jaundice". When I was a medical student the chief residents would like to tease the medical students by testing their basic knowledge. They would say, "what do we do if the Bile level is too low. Do we have to order some for the patient?". The really serious medical students, the ones that were used to getting an A every time on every test, would get really stressed out wracking their brains trying to figure out the answer. It was a good lesson. If the resident pushed the question too hard, it became a particular kind of torture known as "pimping" the student. I think at that point the lesson was lost, and a different lesson was learned. That was that some humans in charge can be cruel. That lesson was learned as well, usually in the third year of med school.
Anyway, if the maternal liver functions normally, then the bile is excreted from the body and all is good. If the bile is not excreted, then it builds up in the blood. The scientists and professors of medicine are able to subdivide the types of "hyperbilirubinemia" into many different kinds, depending on where the obstruction is. They can sometimes find a specific defect in a specific molecule in the body. This is called molecular medicine and is really impressive to those who can appreciate this kind of thing.
The pregnancy cholestasis is called "intrahepatic cholestasis of pregnancy" and is specific to pregnancies. It is fully treatable by delivery. Some medicines can also help reduce the bile in the blood.
Cholestasis of Pregnancy is not very dangerous to the Mother. The itching may be awful, and she may be miserable with it, but it doesn't do long term damage. Many liver failure diseases are fatal, but this isn't one of them. Once delivered, the moms recover fine.
Cholestasis of Pregnancy is very dangerous to the fetus. There seem to be two risks to the baby, ultimately leading to an unpredictable sudden fetal mortality. The first of all, is that the bile gets into the baby and the baby's liver becomes overworked, trying to do the job of the mothers liver. This liver can swell and fail. This might kill the baby. The second is that the bile is toxic to the fetal heart. We think that some babies actually have heart attacks due to the toxic effects of bilirubin on the fetal heart. This kind of toxic reaction is not predictable. It is sudden and unexpected.
Cholestasis of pregnancy is difficult to diagnose properly, and has a causes a ton of stress for women and those around them. Why is it hard to diagnose? Because many pregnant women are itchy. It is very common that a pregnant women will have "PUPP" syndrome. This is "Pruritic Urticaria and Papules of Pregnancy". This usually causes a itchy rash on the abdomen over the top of the pregnancy. Pupp is a self limiting benign kind of problem that can be treated symptomatically. But if she is itchy, and her "bile acids" are elevated, then the diagnosis becomes much more severe. To help differentiate the problem, the itchiness of cholestasis almost always affects the palms and the soles of the feet. The itchiness of Pupp is usually mostly on the abdomen. There is another big diagnosis that overlaps with Cholestasis, and that is Toxemia of Pregnancy. This is also called PreEcclampsia of Pregnancy. PreEccclampsia causes hyptertension, hyperbilirubinemia, and sometimes liver failure. It is extremely common, and in mild cases strikes up to 1 in 20 pregnancies. It is much less common in low risk young healthy women, but more common in older women who may have hyptertension, diabetes, heavy weight, and very stressful lives. Stress can elevate blood pressures and exacerbate toxemia.
Many years ago, the incidence of cholestasis was quoted as one in a thousand. This meant that a reasonably experienced obstetrician, who saw a low risk population of healthy young pregnant girls, may go a whole career without seeing a case of cholestasis. Since it wasn't on their radar, the Ob's would not think of cholestasis when presented with an itchy patient. Since most pregnant women are itchy, they would just attribute it to normal Pupp, or dry skin. They may even get a dermatology consult and the patient would be treated symptomatically. These patients are not colored by Jaundice, so that doesn't help.
In recent years, the incidence of cholestasis has gone up from 0.1 percent, to more than 10 times higher. There are several reasons. One, the genetic melting pot means that there are more people around with the Nordic genes, or the native South American genes, so there are more people at risk. Two, I think that since Ob's see it more often, the diagnosis is suspected more often. Once it is suspected then the lid is off the pot, and we can diagnose it. Once we see it then we can identify it, test for it, monitor it, treat it, and deliver the babies earlier. This means the reported incidence increases because doctors are getting better at diagnosing it, not because of an actual increase.
Importantly, I think that taking the lid off the pot will save babies lives.
Some genetic groups are at a very high risk of cholestasis. Swedes have more, and native Chilean's have risks above 20 percent. It seems to be a genetic factor involved there with some molecule that moves the bile through the liver.
When we are faced with cholestasis, we must get the baby out before there is an adverse event. The standard, if there is one, is to deliver at 37 weeks, at the cusp of term. Some say 38 weeks. And there are still some around who don't deliver early. Before term, we monitor for toxemia and fetal health, and deliver if there is toxemia or some other distress to the baby.
Thanks for reading my blog.
My post on contraceptive options is coming up soon. I have many other posts in mind as well.
Doctor John Marcus MD FACOG
Obstetrician and Gynecologist
Ridgewood NJ 07450
Phone 201-447-0077
blog at doctorjohnmarcus.blogspot.com
Well understand by me. The details are just wonderful.
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