Obesity

Initial Evaluation

• BMI ≥ 85th Percentile
• → History and physical examination

Abnormal — Additional evaluations based on findings

• • Attenuated growth velocity → Endocrine evaluation
• • Neurodevelopmental abnormalities or severe hyperphagia → Genetic evaluation
• • CNS injury → Hypothalamic obesity → Reevaluate pituitary function and/or hormone therapy

Anti-psychotic drug use

• → Reevaluate drug therapy/choice

Normal — Evaluate for obesity comorbidities (Table 60.2)

• • Present → Initiate lifestyle changes and specific treatment of co-morbidity: - Continued weight gain > 6 months → Consider pharmacotherapy and/or surgery (Data supporting use of these interventions are limited to pubertal individuals) - Weight loss/stabilization → Maintain support for lifestyle changes and co-morbidity treatment
• • Absent → Initiate lifestyle changes → Continued weight gain → re-evaluate for obesity comorbidities

Genetic Evaluation — Is there developmental delay?

• Yes → Karyotype: DNA methylation studies: • Positive → Prader-Willi syndrome • Negative → Is there evidence of retinal dystrophy, photophobia, or nystagmus? - Positive → Bardet-Biedl syndrome, Alstrom syndrome, Tub deficiency - Negative → Albright hereditary osteodystrophy, BDNF, TrkB, SIM1 deficiency
• Negative → Measure leptin, insulin*, and proinsulin*: • Positive → Congenital leptin deficiency, PCSK1 deficiency • Negative → Molecular genetic studies → Leptin/leptin receptor deficiency, POMC deficiency, MC4R deficiency, SH2B1 deficiency, KSR2 deficiency