This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.
|Medical Terms||Other Names||
|80%-99% of people have these symptoms|
Delayed pubertal development
Delayed pubertal growth
Pubertal delay[ more ]
Mental retardation, borderline-mild
Mild and nonprogressive mental retardation
Mild mental retardation[ more ]
Flat, discolored area of skin
|Multiple cafe-au-lait spots||0007565|
Multiple fatty lumps
|Specific learning disability||0001328|
Firm lump under the skin
Growth of abnormal tissue under the skin[ more ]
|30%-79% of people have these symptoms|
|Attention deficit hyperactivity disorder||
Attention deficit disorder
Attention deficit-hyperactivity disorder
Childhood attention deficit/hyperactivity disorder[ more ]
Undescended testis[ more ]
Hearing defect[ more ]
Different colored eyes
Poor memory[ more ]
|Neurological speech impairment||
Speech impediment[ more ]
Pins and needles feeling
Tingling[ more ]
Eyeballs bulging out
Protruding eyes[ more ]
Increased fracture rate
Multiple spontaneous fractures
Varying degree of multiple fractures[ more ]
|Slender long bone||
Long bones slender
Thin long bones[ more ]
Increased body height
|5%-29% of people have these symptoms|
|Abnormal eyelid morphology||
Abnormality of the eyelid
Abnormality of the eyelids[ more ]
|Abnormal hair quantity||0011362|
|Abnormality of retinal pigmentation||0007703|
|Abnormality of the hip bone||
Abnormality of the hips
|Abnormality of the respiratory system||0002086|
|Abnormality of the upper urinary tract||0010935|
Narrowing of an artery
Clouding of the lens of the eye
Cloudy lens[ more ]
Birth defect that causes a hole in the innermost layer at the back of the eye
|Chronic myelogenous leukemia||0005506|
Outward bowing at knees[ more ]
Too much cerebrospinal fluid in the brain
|Hypopigmented skin patches||
Patchy loss of skin color
Stiff joints[ more ]
Round back[ more ]
Increased size of skull
Large head circumference[ more ]
Nearsightedness[ more ]
|Neoplasm of the gastrointestinal tract||
Gastrointestinal tract tumor
GI tract tumor[ more ]
Early onset of puberty
Early puberty[ more ]
Decreased body height
Small stature[ more ]
|Urinary tract neoplasm||0010786|
Loss of eyesight
Poor vision[ more ]
|1%-4% of people have these symptoms|
Freckles in groin region
|Optic nerve glioma||0009734|
|Renal artery stenosis||
Narrowing of kidney artery
|Percent of people who have these symptoms is not available through HPO|
Widely spaced eyes[ more ]
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If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.
If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.
You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.
Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.
Conditions with similar signs and symptoms from Orphanet
Legius syndrome (see this term) is often clinically indistinguishable from NF1 and is seen in about 2% of people fulfilling NF1 diagnostic criteria. There are however a small number of individuals with NF1 who like Legius syndrome patients do not develop non-pigmentary manifestations. Constitutional mismatch repair deficiency syndrome should be considered. Other differential diagnoses include McCune-Albright syndrome, Noonan syndrome with lentigines and Proteus syndrome. Most cases of multiple non-ossifying fibromatosis are cases of NF1 (see these terms).
Visit the Orphanet disease page for more information.
Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.
Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.
Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.
These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.
Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.