Rabson Mendenhall Syndrome: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 2, 2026.
What kind of doctor treats Rabson Mendenhall Syndrome?
An endocrinologist usually leads care because the condition affects insulin and growth. A geneticist can confirm the diagnosis and help families understand inheritance. Other specialists may help with specific symptoms. 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 it is
Rabson Mendenhall syndrome is a very rare condition that a child is born with. It affects the way the body uses insulin, the hormone that moves sugar from the blood into cells for energy. Children with this syndrome have extreme resistance to insulin and need far more of it than normal to control blood sugar. It also affects growth, skin, teeth, and other parts of the body.
Symptoms
Symptoms usually show up in infancy or early childhood. Children may develop dark, thick, velvety patches of skin called acanthosis nigricans, often on the neck, armpits, or groin. Other signs include very high blood sugar that is hard to control, a large lower jaw, big ears, overgrowth of nails and hair, and problems with teeth and bones. Children may lose weight and feel weak even while eating well.
Causes and who gets it
The syndrome is caused by changes in a gene called INSR, the receptor that lets insulin work in cells. It is inherited in an autosomal recessive way, meaning a child must get one changed copy from each parent. Parents carrying only one copy usually have no symptoms.
How doctors diagnose it
Doctors look at the child's symptoms, growth, and physical features, then run blood tests showing very high insulin levels along with high blood sugar. Genetic testing can confirm the diagnosis.
Treatment
There is no cure, so treatment focuses on controlling blood sugar and managing symptoms. High doses of insulin, and sometimes medicines like metformin, may be used, though insulin resistance makes control difficult.
When to see a doctor
See a doctor if a child has very slow growth, dark velvety skin patches, or blood sugar that stays high despite treatment. Sudden weight loss, extreme thirst, frequent urination, or weakness need prompt attention.
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 costs more and often works alongside insurance. Either one can spend extra time coordinating care for a rare condition and refer families to specialists when needed.
Common questions
Is Rabson-Mendenhall syndrome a type of diabetes?
It is related to diabetes because both involve insulin and blood sugar, but it is a distinct inherited syndrome with extreme insulin resistance from birth, much more severe than type 2 diabetes, and it causes physical features diabetes does not.
Can Rabson-Mendenhall syndrome be prevented?
There is no known way to prevent it because it is caused by inherited gene changes. Families with a history of the condition can talk to a genetic counselor about the chance of passing it to a child.
How serious is Rabson-Mendenhall syndrome?
The condition is serious, and many reported cases have shortened lifespans, often due to problems from very high blood sugar. Every child is different, so families should discuss their child's situation with their care team.
Can it be found before birth?
Genetic testing can sometimes detect the condition before birth if the family's gene changes are already known, usually requiring a sample such as amniotic fluid. A genetic counselor can explain whether this makes sense for a family.
Sources
- NIH Genetic and Rare Diseases Information Center - Rabson-Mendenhall syndrome
- MedlinePlus Genetics - Rabson-Mendenhall 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.
