Evaluation and Treatment for Turner Syndrome

Jennifer Sprague, MD, PhD, discusses the evaluation and treatment for Turner Syndrome and the Turner's Clinic at the St. Louis Children's Hospital Specialty Care Center.
Evaluation and Treatment for Turner Syndrome
Featured Speaker:
Jennifer Sprague, MD, PhD
Jennifer Sprague, MD, PhD areas of Clinical Interest are Type 2 diabetes in adolescents, polycystic ovary syndrome (PCOS), endocrine complications of obesity, pediatric endocrine disorders, Type 1 and Type 2 diabetes.


Transcription:
Evaluation and Treatment for Turner Syndrome

Melanie Cole (Host): Welcome, our topic today is the evaluation and treatment for Turner Syndrome. My guest is Dr. Jennifer Sprague. She’s a Washington University pediatric endocrinologist at St. Louis Children’s Hospital. Dr. Sprague, let’s start the segment with a description of Turner Syndrome.

Dr. Jennifer Sprague (Guest): Sure Turner Syndrome is a genetic disorder affecting girls and women that are missing all or part of one of their X chromosomes and they have to have at least one clinical feature like short stature, premature ovarian failure, or certain cardiac defects. About one in 2,000 to 4,000 women are affected or girls are affected and it affects multiple organ systems so they need a multidisciplinary approach to care.

Melanie: Do we know what causes it?

Dr. Sprague: It’s caused by loss of all or part of one of the X chromosomes in some or all cells. It’s very common at conception to be missing one of the X chromosomes and often leads to early pregnancy loss. It’s estimated to account for up to about 10% of first trimester miscarriages. Many people think that those who are liveborn with 45, X karyotype actually may have some cryptic mosaicism, meaning some of their cells do have two X chromosomes. Now that said, on standard karyotyping, about 40% to 50% of girls with Turner Syndrome have monosomy X.

Melanie: Why does it affect only females? And tell us a little bit about when it is diagnosed, would this be something you would notice in utero or after the baby is born?

Dr. Sprague: Sometimes it is diagnosed in utero if there’s a cystic hygroma or hydrops or sometimes left sided heart defects on ultrasound will prompt workup. Sometimes quad screens can also prompt a workup for Turner Syndrome, but it can be diagnosed at any age from prenatal to adult. It affects only females because that’s part of the definition. You have to a phenotypic female. If you’re phenotypically male and are found to have a 45 X, 46 X Y karyotype, we actually classify you as mixed gonadal dysgenesis. Those boys could be under virialized and could have impaired testicular function, but some do have spontaneous puberty.

Melanie: Tell us about the Turner’s Clinic at St. Louis Children’s Hospital Specialty Care Center?

Dr. Sprague: So the Turner’s Clinic has been around for about a year, although we’ve been taking care of girls with Turner Syndrome for a much longer period of time. It coordinates endocrinology follow up, renal follow up, cardiology, and also coordinates a lot of the screening studies that these girls need. They need audiology. They need regular echocardiograms and EKGs and a lot of coordinated services, so it’s a great resource to make sure that these girls are getting all the healthcare that they need.

Melanie: As you’ve mentioned different providers that are involved, speak about that improved coordination of care between providers and how are you all working together?

Dr. Sprague: So by putting all the providers in one location, it lets the girls get all their screening done at one time, but it also let’s us talk and understand what the impact of one problem may have on how we’re approaching something else. So for example, all the girls are followed by cardiology. Some of them have significant heart defects that need intervention or might affect our ability to start them on growth hormone or on estrogen replacement, which most of these girls do need and so it facilitates that discussion so we can take the best possible care of these patients.

Melanie: And as you’ve got this all in one place, how important is a medical home for well child and chronic care visits with their normal provider?

Dr. Sprague: That is still very critical. We are available to coordinate their ongoing screening and their Turner specific care, but every kid still gets common illnesses. They need their medical home to take care of their everyday illness and to help get in touch with us if there’s something not going right and the family’s having trouble sorting it out.

Melanie: Speak about how these young women age and what complications or long term effects that they might have as a result of their Turner Syndrome and what are the risks of a daughter, if the parents have Turner Syndrome, of the daughter having another daughter with Turner Syndrome?

Dr. Sprague: So I’ll speak to that first. There’s generally not a risk of a daughter of a women with Turner Syndrome having Turner Syndrome beyond the usual population risk. Most women with Turner Syndrome do have ovarian failure. Most have infertility. They can go on to have children. Some do have spontaneous pregnancies, but most pregnancies are from a donor egg or many women will have adoption. Because they have ovarian failure, most are getting estrogen replacement therapy to facilitate going through puberty and to maintain normal secondary sex characteristics and that’s usually managed by an endocrinologist in the adolescent years, although could be managed by an OB/GYN just with birth control pills later on depending on the resources available for the adults. These girls also see the endocrinologist related to their growth. So girls with Turner Syndrome are significantly shorter than population and so they’re treated with growth hormone to promote a more normal final height outcome, and starting that treatment early can improve that final height and make it easier for them to do activities of daily living when they get to be an adult. The most serious long term complication really has to do with the heart. So these girls can get aortic dissection. They’re at higher risk of hypertension and so they need regular cardiac screening, and particularly if they do go on to have pregnancy, they require very close cardiac monitoring because of that risk of aortic dissection.

Melanie: Dr. Sprague, what else would a referring physician want to know about Turner Syndrome? What would you like to tell other providers and pediatricians and what can they expect after referring a patient to the Turner’s Clinic at St. Louis Children’s Hospital?

Dr. Sprague: I’d like them to always keep Turner’s Syndrome in their differential. If they’re working up a girl for short stature or seeing someone with delayed puberty or cardiac defects because we really can make a difference in their lives. Early growth hormone treatment can improve their final height. We can facilitate more normal social adjustments by helping them through puberty and they can lead normal long term lives, but they do need coordinated care in order to do that. When a patient is referred to the Turner Syndrome Clinic, if we have a known diagnosis of Turner Syndrome, then they would likely get a discussion of growth hormone treatment and pubertal induction at their first visit depending on the age of the patient and we would start arranging all the screening studies that are recommended. If the diagnosis is not known, then they’re probably not going to be in the Turner Syndrome Clinic at their first visit. It would be more likely they’d see endocrinology for workup of their short stature or their delayed puberty and then after other causes were ruled out, we might end up with a diagnosis of Turner Syndrome after genetic testing was sent.

Melanie: Give us a little blueprint for future research. Where do you feel will be the most important areas as far as Turner Syndrome and some of those long term complications? Tell us what you see in the future.

Dr. Sprague: So a lot of the focus right now is on optimizing the growth outcomes and the puberty outcomes, and also in just knowing exactly when to screen for much of the cardiac problems and what the best approach is for that to minimize their long term risk.

Melanie: Thank you so much for being with us today, Dr. Sprague and sharing your expertise and explaining the Turner’s Clinic at St. Louis Children’s Hospital Specialty Care Center. A physician can refer a patient by calling Children’s Direct Physician Access Line at 1-800-678-HELP, that’s 1-800-678-4357. You’re listening to Radio Rounds with St. Louis Children’s Hospital. For more information on resources available at St. Louis Children’s Hospital, you can go to stlouischildrens.org, that’s stlouischildrens.org. This is Melanie Cole, thanks so much for listening.