Several factors should be considered when clinically diagnosing BBS
Look at your patient's complete presentation
Clinical manifestations1-3
- BBS is a ciliopathy with a highly variable phenotype and clinical features that vary greatly across individuals and evolve over time
- Some features may present more mildly or slowly depending on gene variant and other factors
Download
Genetics3
- Genetic testing for BBS can provide additional diagnostic information to help inform your diagnosis. For more information, visit UncoveringRareObesity.com
- Results should be integrated into the overall clinical assessment of the patient and do not equate to a diagnosis on their own. Additionally, variant interpretation may change over time, as the information around the genetics of BBS continue to evolve
Patient history
- Review patients’ complete medical history. Some clinical manifestations of BBS may have been previously treated and/or not recognized as a symptom of BBS
Family findings1,4
- Family members have an increased risk of inheriting a pathogenic BBS gene, and siblings are generally diagnosed earlier
- Once one family member is diagnosed, others should be evaluated for BBS as well
- Phenotype can vary between siblings
Announcing the ICD-10 code for BBS—Q87.83—effective as of October 1, 2023
BBS has a highly variable phenotype with key identifiable features2
BBS is clinically and genetically diverse, so not all people with BBS will present the same way or with all of these features1,3
| Birth | First years of life(0 to 5 years) | Eary childhood(up to 10 years) | Adolescence to adulthood(>10 years) | |
|---|---|---|---|---|
| Postaxial polydactyly2,4-7 | Extra digits (postaxial) | Typically surgically removed | ||
| Renal anomalies2,4,8 | Anatomical malformations | Progressive kidney disease | Polyuria/Polydipsia | Chronic kidney disease |
| Hyperphagia and obesity2,9-12 | Normal birth weight | Rapid weight gain leading to early-onset, severe obesity, unusual food seeking | Hyperphagia and severe obesity persist | Continued hyperphagia and severe obesity persist, presenting as truncal obesity for adults |
| Cognitive impairment2,13 | Developmental delay, speech delay | Specialized schooling needs, behavioral difficulties | Learning difficulties | |
| Visual impairment2,14 | Progressive vision loss, night blindness | Legal blindness | ||
| Hypogonadism2,13 | Delayed puberty, genital anomalies |
Diagnosing BBS in your practice
Recognize the various clinical manifestations of BBS to accelerate a diagnosis for your pediatric and adult patients
Uncovering Rare Obesity® can help support a BBS diagnosis
A no-charge,* extensive genetic testing program for MC4R pathway diseases
Extensive panel offers broad insights1
More than 20 genes have been found to be associated with BBS. The gene panel includes 79 genes and 1 chromosome region, reflective of nearly all of the most frequently tested genes associated with obesity.
Tailored support for results interpretation
Access to a geneticist to help interpret results and licensed genetic counselors for your patients are available. Services are provided through third-party partners.
Testing conducted by a laboratory partner
DNA testing is conducted by PreventionGenetics, a CLIA-accredited clinical laboratory.
Blood and OCD-100 buccal swab
sample collection kits are available.
For more information about the genetic testing program, visit UncoveringRareObesity.com
*Rhythm Pharmaceuticals covers the cost of the test and provides sample collection kits. Patients are responsible for office visit, sample collection, or other costs.
See an overview of BBS
CLIA=Clinical Laboratory Improvement Amendments.
References: 1. Forsythe E et al. Front Pediatr. 2018;6:23. doi:10.3389/fped.2018.00023. 2. Forsythe E et al. Eur J Hum Genet. 2013;21(1):8-13. 3. Manara E et al. Ital J Pediatr. 2019;45(1):72. 4. Forsyth R et al. Bardet-Biedl syndrome overview. In: Adam MP et al, eds. GeneReviews®. University of Washington; 2003. Updated July 23, 2020. Accessed August 11, 2023. 5. Khan OA et al. Cureus. 2019;11(2):e4114. 6. Agrawal H et al. Pediatr Rev. 2018;39(5):e21-e23. 7. Vlahovic AM et al. Pediatric and Adolescent Plastic Surgery for the Clinician. Springer;2017:89-105. 8. Putoux A et al. Pediatr Nephrol. 2012;27(1):7-15. 9. Sherafat-Kazemzadeh R et al. Pediatr Obes. 2013;8(5):e64-e67. doi:10.1111/j.2047-6310.2013.00182.x. 10. Pomeroy J et al. Pediatr Obes. 2021;16(2):e12703. 11. Katsanis N et al. Hum Mol Genet. 2001;10(20):2293-2299. 12. Eneli I et al. Appl Clin Genet. 2019;12:87-93. 13. Beales PL et al. J Med Genet. 1999;36(6):437-446. 14. Weihbrecht K et al. Med Res Arch. 2017;5(9):10.18103/mra.v5i9.1526. doi:10.18103/mra.v5i9.1526.