Common Symptoms of Bardet-Biedl Syndrome
Understanding How BBS Affects the Body
Bardet-Biedl Syndrome (BBS) is often referred to as a “multisystem disorder” because it affects many parts of the body in a wide variety of ways. Understanding the common symptoms can help individuals and families recognize early signs and seek proper diagnosis and care.
1. Vision Loss (Retinal Dystrophy)
The most consistent and often earliest symptom of BBS is progressive vision loss. This is due to a condition called retinitis pigmentosa, which affects the retina—the light-sensitive tissue at the back of the eye.
- Symptoms may begin with night blindness in childhood
- Peripheral vision loss follows, often leading to tunnel vision
- In many cases, complete blindness occurs in adulthood
2. Kidney Abnormalities
Up to 80% of individuals with BBS experience some form of kidney problem. These can range from mild structural differences to serious complications that affect kidney function.
- Increased risk of chronic kidney disease
- Monitoring and early intervention are crucial to protect long-term health
3. Obesity
Childhood-onset obesity is one of the hallmark features of BBS.
- Not due to lifestyle alone—linked to the way BBS affects hunger and metabolism
- May increase risk for diabetes, hypertension, and cardiovascular disease
4. Polydactyly (Extra Fingers or Toes)
Many children with BBS are born with extra digits on their hands or feet, a condition known as polydactyly.
- Typically identified at birth
- May be surgically corrected in early childhood
5. Intellectual and Developmental Delays
While not all individuals with BBS have learning difficulties, developmental delays are common.
- Speech delays and difficulty with motor coordination
- Mild to moderate intellectual disability in some cases
- Supportive therapies can significantly improve outcomes
6. Hormonal and Reproductive Challenges
BBS can affect the endocrine system, leading to hormonal imbalances.
- Delayed puberty or infertility may occur
- Male genital abnormalities are also reported in some cases
7. Additional Symptoms
Other possible symptoms include:
- Dental anomalies
- Behavioral challenges or autism-like features
- Heart defects (in a minority of cases)
Recognizing the Pattern
It’s important to remember that not every person with BBS will have all these symptoms. However, a pattern of multiple signs—especially vision problems, obesity, and polydactyly—can point doctors toward a correct diagnosis.
Up Next: How is Bardet-Biedl Syndrome Inherited?
In the next post, we’ll break down the genetics of BBS, explain how it’s passed down in families, and highlight the importance of genetic counseling for affected individuals and their loved ones.