Obesity in Children

Question 1

Drugs that can cause weight gain

Answer 1

anticonvulsants - valproic acid, carbamazepine
antipsychotics - risperidone
corticosteroids

Question 2

Overweight

Answer 2

BMI > +1 SD (z-score +1) but < +2 (z-score of +2) for age and sex
equivalent to BMI of 25kg/m2 at age 19

Question 3

Obese

Answer 3

BMI >/= +2 SD (z-score +2) for age and sex

equivalent to BMI 30kg/m2 at age 19

Question 4

Complications or comorbidities NB

Answer 4

associated with increased morbidity and mortality
intertrigo
furunculosis
Hidradenitis suppurativa
Acanthosis nigricans - associated insulin resistance - hyper pigmented lesions

PCOS
premature adrenarche
type 2 DM - insulin resistance

Cholelithiasis
NAFLD

pseudomotor cerebri

Blount’s disease
SCFE - slipped capital femoral epiphysis

Depression
decreased self-esteem
decreased QOL
depression

Obstructive sleep apnoea
reactive airway disease

Screen for
Type 2 DM
Dyslipidaemia
Fatty liver disease (ALT)

Question 5

Endocrine disorders associated

Answer 5

Hypothyroidism 
Cushing's syndrome - cortical excess 
Pseudohypoparathyroidism 
Growth hormone deficiency 
Hypothalamic disorders - craniopharyngioma 
Type 2 DM 

increased BMI or weight for height
BUT stunted - decreased height for age

Question 6

Genetic syndrome associated

Answer 6

Prader-Willi
Bardet Biedl
Beckwith Wiedemann
Cohen

typically have

• Early onset obesity
• Short stature
• Dysmorphic features
• Developmental delay and intellectual disability
• Hypogonadism
• Retinal changes
• Deafness

Question 7

Causes

Answer 7

lack of exercise 
excessive time - TV, video games, computers
psychological causes overeating 
- boredom 
- insecurity
- poor family relationships 
mental and physical handicaps 
drugs - anticonvulsants, valproic acid, carbamazepine, corticosteroids

Question 8

Special investigations

Answer 8

fasting glucose - 5.6 - 6.9 mmol/l or HbA1C > 5.7% = do oral glucose tolerance test
hyperlipidaemia = fasting total cholesterol > 5.18 mmol/l
or LDL > 3.38 mmol/l
check ALT = fatty liver disease

Question 9

when to consider treatment

Answer 9

BMI > +2 z-score OR > +1 z-score and co-morbidities (HPT, impaired glucose tolerance, hyperlipidaemia)

Question 10

Differential diagnosis obese child

Answer 10

large infants - idiopathic or simple obesity 
---- length corresponding to weight on z score lines 
---- symmetrically large 
----- not case in obese infants 
endocrine disorders 
genetic syndromes 
single gene defects 
CNS disorders 
miscellaneous

Question 11

Single Gene defects

Answer 11

Leptin signalling pathway defects
rare causes of obesity
endocrine or genetic tests only need to be performed in obese children who are ALSO short & /or not growing