Obesity Algorithm

Question 1

What satiety hormone is elevated in Roux en Y bypass is elevated and why?

Answer 1

GLP-1. Because surgery bypasses the proximal small intestine therefore you have rapid transit of food to the distal small intestine and thus, higher levels of GLP1 will increase.

Question 2

Why does Roux en Y surgery help diabetes?

Answer 2

Because you have elevated GLP-1 so you have decrease in hepatic gluconeogenesis which is usually always turned on in diabetics.

Question 3

What is the most common monogenic defect predisposing to obesity?

Answer 3

MC4R

Question 4

What are features of MC4R deficiency?

Answer 4

Hyperphagia
Tall stature
Insulin resistance
Autosomal recessive or dominant
Higher leptin/LR

Question 5

What are features of POMC deficiency?

Answer 5

Decreased ACTH which can lead to congenital adrenal insufficiency
Decreased alpha MSH as POMC makes this too.
Pale skin/red hair - hypopigmentation
Autosomal Recessive
Hyperphagia

Question 6

What are features of Lepr deficiency and congenital leptin deficiency?

Answer 6

LepR - normal or elevated Leptin,
Congenital - undetectable leptin
Both have - hyperphagia, hypogonadism
Impaired T cell - frequent infections
Autosomal recessive
Can use Setmelanotide for LEPR deficiency.
Can use Metreleptin for Congenital lefptin deficiency with lipodystrophy

Question 7

What are features of Bardet Biedl Syndrom?

Answer 7

Rare
Hyperphagia
Vison loss- retinitis pigmentosa which can lead to night blindness
Renal disease
Metabolic syndrome
Delayed puberty
Polydactyly
Can use Setmelanotide to help obesity

Question 8

What conditions is Setmelanotide approved for?

Answer 8

POMC
LEPR deficiency
Bardet Biedl

Question 9

What are features of Cohen Syndrome?

Answer 9

Chromosome 8p22 mutation
Central obesity - thin arms/legs
Thick hair, eyebrows and eyelashes
Small face
Developmental delay
Retinal dystrophy
Hypermobility
Overly friendly
Neutropenia
Some will have seizures and deafness
Autosomal recessive

Question 10

What are some features of Prader Willi?

Answer 10

High Ghrelin and low leptin
Hypotonia and poor feeding at birth
Hyperphagia at age 2
Thin face with almond shaped eyes
Delayed development and intellectual impairment
Hypogonadism
Paternal chromosome 15 - partial loss of function, deletion of q11-13 region
Most common form of syndromic obesity

Question 11

What are some features of Albright’s Hereditary Osteodystrophy?

Answer 11

Short Stature
Pseudohypoparathyroidism
Dental abnormalities
Round face
Shortened fingers/toes
Resistance to several hormones
Genetic imprinting in autosomal dominant manner

Question 12

What are some features of PCKS1 deficiency?

Answer 12

Severe weight loss and diarrhea seen in infancy, increase in appetite and weight gain by 2yo
poor linear growth

Question 13

Beckwith-Weidermann Syndrome

Answer 13

11p15.5 mutation
Macroglossia
Hepatosplenomegaly
hypoglycemia in 30-50% of babies
predisposition to tumor development

Question 14

Alstrom Syndrome

Answer 14

Photophobia
Nystagmus
Deafness
Blindness
Diabetes

Question 15

What does indirect calorimetry estimate?

Answer 15

REE

Question 16

How does indirect calorimetry estimate REE?

Answer 16

Measure carbon dioxide production and oxygen consumption. It is reimbursible.

Question 17

What does direct calorimetry measure?

Answer 17

Total energy expenditure -measures heat generated by organism via enclosed chamber

Question 18

What makes up total energy expenditure?

Answer 18

REE(60-75%) + TEM(10%) + EEPA(15-30%)

Question 19

What does Mifflin St Jeor measure?

Answer 19

REE

Question 20

What equations can measure REE?

Answer 20

Mifflin St Jeor and Harris Benedict equations

Question 21

What are features of lipedema?

Answer 21

Lipodystrophy
Affects women ages 15-30
Feels like nuts/rice/peas
Cuff sign
Spares feet
Subcutaneous fat accumulation in lower body
Soft, minimal pitting

Question 22

What are the Orexigenic neurotransmitters?

Answer 22

NPY
AgRP
MCH
Orexin A and B

Question 23

What are the Anorexic neurotransmitters?

Answer 23

POMC
CART
Alpha melanin stimulating hormone
Serotonin

Question 24

What is NPY inhibited by?

Answer 24

Insulin
Leptin
PYY
Serotonin

Question 25

What is AgRP inhibited by?

Answer 25

Insulin
Leptin
PYY
Serotonin

Question 26

What is Orexin A/B stimulated and inhibited by?

Answer 26

Stimulated by NPY/AgRP
Inhibited by Leptin

Question 27

What is MCH stimulated and inhibited by?

Answer 27

Stimulated by NPY/AgRP
Inhibited by Leptin

Question 28

What is POMC/CART stimulated and inhibited by?

Answer 28

Stimulated by Serotonin, Insulin and Leptin
Inhibited by NPY and GABA

Question 29

If arrested height but accelerated weight, what would you worry about in child?

Answer 29

Hormonal issue and should check TSH/T4, Dexamethasone suppression test and 24 hour urinary cortisol

Question 30

What is REE?(Weir equation)

Answer 30

VO2 and VCO2.

Question 31

What is VO2?

Answer 31

Oxygen uptake and consumption

Question 32

What is VCO2?

Answer 32

Carbon dioxide production/elimination

Question 33

What increases VO2?

Answer 33

Exercise
Overfeeding - thermic effect of meals
Shivering
Hyperthermia

Question 34

What increases VCO2?

Answer 34

Metabolic acidosis
Hyperventilation
Excessive Carb intake
Hypermetabolism

Question 35

What decreases VO2?

Answer 35

Paralysis
Starvation/fasting
Hypothyroidism
Hypothermia

Question 36

What decreases VCO2?

Answer 36

Metabolic Alkalosis
Hypoventilation
Starvation/ketosis
Hypometabolism