Costello Syndrome: Causes, Symptoms, and Treatment
Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Costello Syndrome?
A clinical geneticist (a doctor who finds inherited conditions) and a pediatrician (a children's doctor) usually lead care. A cardiologist, a heart doctor, often helps too. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is Costello syndrome?
Costello syndrome is a rare disorder that affects many parts of the body. It is marked by delayed development, loose folds of skin, unusually flexible joints, heart problems, short stature, and distinctive facial features.
It is very rare. It probably affects 100 to 1,500 people worldwide. The effects vary from mild to severe.
Symptoms
Children are often delayed in reaching milestones, such as speaking, sitting, and walking. Some have intellectual disabilities that vary in severity.
Typical facial features include a prominent forehead, full cheeks, and full lips. Most infants have trouble eating and grow more slowly than other children. Some have constipation or acid reflux. They are short compared to their family and peers. Some have low growth hormone levels.
Heart problems are common. They include an abnormal heartbeat, structural heart defects, and hypertrophic cardiomyopathy, a disease that enlarges and weakens the heart muscle.
Other problems can include:
- Seizures.
- Weak muscle tone.
- Vision problems, such as nearsightedness or crossed eyes.
- Hearing loss.
- Tight Achilles tendons.
- Dry and thickened skin.
- Recurrent respiratory infections.
- Dental problems.
Causes and who gets it
Changes in the HRAS gene cause Costello syndrome. The signs overlap with two other conditions, cardiofaciocutaneous syndrome and Noonan syndrome.
Small, wart-like growths called papillomas often form around the nose and mouth.
Starting in early childhood, people with Costello syndrome have a higher risk of certain tumors. The lifetime risk of a cancerous tumor is about 15 percent.
How doctors diagnose it
Doctors look at the signs and do a genetic test for a change in the HRAS gene. Doctors can tell it apart from the look-alike conditions by the genetic cause.
Treatment
Poor weight gain and growth, called failure to thrive, is the most common and hardest problem. Most infants need tube feeding. Heart problems and cancers are treated with standard care.
Sideways bending of the wrists and fingers often needs early bracing and occupational or physical therapy. Tight Achilles tendons may need surgery to lengthen them. Developmental delay needs early intervention programs and individual education plans.
Papillomas that keep coming back may need to be removed. Doctors also do checks over time. A heart ultrasound and heart tracing are done at diagnosis, followed by regular visits with a cardiologist. Ultrasound of the belly and pelvis every three to six months until age eight to ten may be considered to look for tumors. A yearly urine test for blood to screen for bladder cancer starts at age ten. Anesthesia may be risky for people with this heart muscle disease.
When to see a doctor
Children with Costello syndrome need regular checks, including heart checks and tumor checks. Feeding problems and poor growth are common, so tell the doctor about them.
Call 911 or go to the emergency room if a child has a seizure, trouble breathing, or fainting.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can help keep track of the many specialist visits and tests. They can also provide regular follow-up care.
Common questions
Is Costello syndrome the same as Noonan syndrome?
No, but their signs overlap. They can be told apart by their genetic causes.
How rare is Costello syndrome?
It is very rare. It probably affects 100 to 1,500 people worldwide.
Does Costello syndrome cause cancer?
Yes, it raises the risk of certain tumors. The most common cancerous tumor is a childhood cancer called rhabdomyosarcoma.
Are heart problems common in Costello syndrome?
Yes, heart problems are common.
Sources
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
