Rapadilino Syndrome: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Rapadilino Syndrome?
A primary care doctor, such as a pediatrician or family doctor, usually coordinates care. Because the condition affects many parts of the body, specialists are often involved, including an orthopedic surgeon, a geneticist, a gastroenterologist, and an ear, nose, and throat doctor. A direct primary care doctor, paid through a flat monthly fee instead of insurance billing, can be a good fit for families who need frequent check-ins.
What it is
Rapadilino syndrome is a rare condition present from birth. The name comes from its main features. Ra stands for radial ray problems, which affect the thumb and the radius, the forearm bone. Pa stands for patella aplasia, a missing or underdeveloped kneecap. Di stands for diarrhea in babies. No stands for a long, slender nose and normal intelligence.
Symptoms
Children are often smaller than average at birth and grow more slowly. Many have differences in the arms, hands, or thumbs, such as missing, small, or differently placed thumbs. The kneecap may be missing or small. Some babies have long-lasting diarrhea, leading to poor weight gain. Other features include a long, slender nose, a cleft palate, and hearing loss.
Causes and who gets it
Rapadilino syndrome is caused by a change in a gene named RECQL4. It is inherited in an autosomal recessive pattern, meaning a child must receive one changed copy of the gene from each parent. Parents who carry only one changed copy usually have no symptoms.
How doctors diagnose it
Doctors start with a physical exam and a history of growth and family background, looking for the pattern of features linked to the condition. X-rays can reveal problems in the forearm, thumb, or kneecap. A genetic test can confirm the diagnosis.
Treatment
There is no cure. Treatment focuses on managing each person's specific features. Babies with diarrhea may need careful feeding plans and extra fluids. Some children benefit from surgery to improve hand or thumb function or to repair the roof of the mouth. Hearing loss can often be helped with hearing aids.
When to see a doctor
A parent should talk to a doctor if a baby has frequent diarrhea, poor weight gain, or trouble feeding. Differences in the thumbs, arms, or kneecaps, or a mouth opening present at birth, are also reasons to seek care. New symptoms should be discussed with the care team.
Common questions
Is Rapadilino syndrome life threatening?
Most people with the condition do not have life-threatening problems. However, severe diarrhea in infancy can be dangerous if it is not treated. Doctors monitor babies closely for dehydration and poor growth. Outcomes vary from person to person.
Will my child be able to use their hands normally?
Hand and thumb differences vary a lot between individuals. Some children have mild changes. Others need surgery to improve hand function. An orthopedic or hand surgeon can explain what options might help a particular child.
Can Rapadilino syndrome be prevented?
There is no known way to prevent it. This is because it is caused by a gene change inherited from parents. Families with a history of the condition can meet with a genetic counselor. A genetic counselor explains inheritance and testing options before or during pregnancy.
Does everyone with the condition have all the features?
No. Some people have only a few features and others have many. Even within the same family, the condition can look different from one person to the next.
Sources
- NIH Genetic and Rare Diseases Information Center - Rapadilino syndrome
- MedlinePlus Genetics - RAPADILINO syndrome
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.
