Floating-Harbor syndrome (FHS) is a rare genetic disorder that impacts growth and development. Treatments, like growth hormone injections and therapy, can help manage symptoms.
Floating-Harbor syndrome (FHS), also known as Pelletier-Leisti syndrome, typically causes physical characteristics like short stature, delayed bone age, a distinctive triangular facial structure, and challenges with expressive language.
It results from an altered gene. Doctors typically diagnose it during childhood through genetic testing.
Continue reading to learn more about FHS, including its symptoms and cause, and how it’s managed.
FHS can cause physical and developmental symptoms. Not every person with FHS experiences all of these symptoms.
Physical characteristics
FHS can cause low birth weight and affect a child’s growth and development.
FHS affects bone and cartilage development as well as the production of growth hormone, which can result in physical characteristics, such as:
- short height and delayed bone growth
- a triangular-shaped face
- a prominent nose
- long eyelashes
- deep-set eyes with narrow eyelid gaps
- a wider mouth with thin lips
- smaller ears
- structural skeletal differences affecting the spine and other bones in the body
- structural differences in the fingers, such as shorter fingers or one or more fingers that curve to the side
- dental differences
People with FHS may not experience all of these characteristics.
Other symptoms
People with FHS may also experience cognitive effects and effects that impact other body systems. These can include:
- speech and language delays, particularly with expressive language
- intellectual disability
- congenital heart defects
- gastrointestinal issues
- issues affecting the genital and urinary organs, such as hydronephrosis, where one or both kidneys become swollen due to urine buildup, and hydrocele, a swelling in the scrotum
FHS system results from a mutation in the SRCAP gene that typically happens early during the embryo’s development or during the creation of reproductive cells. It isn’t usually inherited.
The SRCAP gene is responsible for encoding the SNF2-related CREBBP activator protein and plays roles in key cellular pathways, including:
- gene expression
- DNA damage response
- cell division
Researchers don’t know exactly what causes the mutation, but some believe it may be related to a growth hormone deficiency.
A pediatrician typically begins diagnosing FHS by taking the child’s and family’s health histories.
They may perform a physical examination and psychological tests to determine if the child has language difficulties or indicators of intellectual disability.
As FHS is a rare syndrome, doctors may also order tests to rule out more common conditions and better understand the symptoms. This may include:
- blood tests to measure a child’s level of growth hormones
- facial dysmorphism study
- genetic testing
Doctors ultimately diagnose FHS through genetic testing and analysis.
Children with FHS typically receive treatment for their specific symptoms to help manage the condition. This may include:
- hormone therapy to administer growth hormones if a child has a deficiency
- speech and language therapy to develop these skills
- support for any behavioral difficulties, such as difficulty paying attention
- treatment for other symptoms, as needed
FHS affects growth and development, but does not necessarily affect a person’s outlook.
Children with FHS may receive treatment to support their physical growth and development. Other treatments, such as speech and language services, may improve their communication over time.
FHS is a rare genetic disease that’s associated with short height, specific body and facial characteristics, and intellectual disability. It may also affect other body systems, including the heart.
People with FHS may have a range of symptoms.
Doctors diagnose FHS through genetic testing. Treatment focuses on addressing an individual’s specific symptoms, but may include hormones to stimulate growth and support services to improve communication.