Hypothyroidism, Hyperthyroidism, Obesity Flashcards
Congenital causes of Hypothyroidism?
1) Maldescent of the thyroid and athyrosis (absence):
Commonest cause of sporadic congenital hypothyroid.
Failure of thyroid gland to descend from sublingual to below larynx in early foetal life.
2) Dyshormonogensis - inborn error of thyroid hormone genesis
3) Iodine deficiency - Commonest cause worldwide but rare in UK (essential for thyroid hormone production).
Acquired causes of hypothyroidism?
1) Prematurity
2) Hashimoto thyroiditis (autoimmune)
3) Hypoituitarism
4) Trisomy 21
Clinical presentation of hypothyroidism?
- MORE PROMINENT WITH AGE
- Congenital - Usually asymptomatic and picked up on screening. Failure to thrive, developmental delay, feeding problems, constipation and prolonged jaundice.
- Acquired - Females affected more than males, cold intolerance, cold peripheries, bradycardia, dry hair and dry skin, pale and puffy eyes, goitre and delayed puberty.
Diagnosis of hypothyroidism?
- GUTHRIE TEST performed on ALL newborn: will show raised TSH (except if secondary to pituitary abnormalities - low TSH)
- Low T4
Treatment of hypothyroidism?
- Thyroxine (T4) treatment: LEVOTHYROXINE started at 2-3 weeks, lifelong treatment.
- EARLY TREATMENT for congenital hypothyroidism essential to prevent learning difficulties.
Hyperthyroidism Ex?
- Most often due to GRAVES DISEASE (Autoimmune thyroiditis secondary to the production of thyroid stimulating immunoglobulin).
- Most often seen in teenage girls.
- Neonatal hyperthyroidism can occur in infants of mothers with Graves Disease due to transplacental transfer of thyroid stimulating immunoglobulin - treatment required as it is potentially fatal, but it is self-resolving.
Clinical presentation of hyperthyroidism?
- Typical child - palpitations, tachycardia, tremor and anxiety.
- Systemic - anxiety, restlessness, sweating, diarrhoea, tachycardia, increased appetite, weight loss, rapid growth in height, advanced bone maturity.
- Eye symptoms - less common in children: Exopthalmous, lid lag/lid retraction.
Diagnosis of hyperthyroidism?
- RAISED T3 and T4 (thyroxine) and low TSH
- Thyroid stimulating antibodies/immunoglobulins
Treatment of hyperthyroidism?
CARBIMAZOLE - risk of neutropenia - seek urgent help + blood count if sore throat and high fever on starting treatment.
ATENOLOL - symptomatic for tachycardia, tremor and anxiety.
What is obesity?
- Defining obesity is more difficult in children as BMI varies with age.
- BMI percentile charts are needed in children <12 years to make an accurate assessment.
Obesity values on percentile charts?
- Overweight = BMI > 91st centile or BMI > 25 (if >12yrs)
- Obese = BMI > 98th centile or BI >30 (if >12 yrs)
Risk factors of obesity?
1) Low socio-economic background
2) Asian (4 times likely)
3) Female
4) Taller children
Aetiology of obesity?
1) Lifestyle factors - high fat diet, lack of exercise
2) GH deficiency
3) Hypothyroidism
4) Down’s syndrome
5) Prader-Willi syndrome
Consequences of obesity in children?
1) Orthopaedic problems - slipped upper femoral epiphyses, Blounts disease (bowing of legs due to tibia abnormality), MSK pans
2) Psychological
3) Sleep apnoea
4) Benign intercranial hypertension
5) Long term - DMT2, HT, CHD
Treatment of obesity in children?
1) Treatment considered if obese (over 98th centile or BMI>30)
2) Healthier eating
3) Physical activity of 60 mins daily
4) Pharmacological (only once non-pharm treatments have failed) - ORLISTAT (Lipase inhibitor - causes steatorrhoea), METFORMIN (biguanide - increases insulin sensitivity, decreases gluconeogenesis and decreases GI glucose absorption)
5) BARIATRIC SURGERY - not indicated in young children until they have achieved maturity - and all other interventions have failed to achieve or maintain weight loss.
