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
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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 patient’s 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
Dedicated ICD-10 code for BBS—Q87.83
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,* genetic testing program for MC4R pathway diseases
Genetic test provides insights
The gene panel includes 87 genes (29 genes associated with BBS) and 1 chromosome region, reflective of nearly all of the most frequently tested genes associated with obesity. This is not a test for Prader-Willi syndrome.1,4
Tailored support for results interpretation
The program provides you with access to a geneticist to help interpret results, as well as board-certified genetic counselors for your patients. 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 March 23, 2023. 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.