Thyrotoxicosis / Pregnancy / Oxford Flashcards
What is the most common cause of thyrotoxicosis in pregnancy?
Graves disease 95 %
What is the prevalence of thyrotoxicosis in pregnancy?
1 / 5000
What are the features of thyrotoxicosis in pregnancy?
Weight loss
Tremors
Persistent tachycardia
Eye signs
What is the effect of pregnancy on thyrotoxicosis?
Improves in 2nd / 3d trimester
Deteriorates in the puerperium
( because pregnancy is a state of immunodeficiency)
What is the effect of thyrotoxicosis on pregnancy?
Subfertility
Miscarriage
IUGR
Premature delivery
Thyroid storm
Fetal thyrotoxicosis occurence in women with Graves disease?
10 % of the babies
What are the features of thyroid storm?
1- pyrexia
2- confusion
3- cardiac failure
What to monitor if antibodies are present in women with a history of Graves disease?
1- fetal heart rate
2- serial USS
3- fetal growth
4- fetal Goitre
What is the half life of thyroid antibodies?
3 weeks……> neonatal hyperthyroidism may occur
What is the aim of treatment in thyrotoxicosis?
To achieve euthyroid with T4 at the upper limit of normal.
Name medications could be used in thyrotoxicosis?
PTU
Carbimazol
B blockers (to relieve symptoms in new cases for a short period of time)
Which anti thyroid drugs is preferred in breastfeeding?
PTU - less transfer into milk
Dose < 150 mg / day
Carbimazol dose < 15 mg / day
TFT in baby should be monitored at higher doses
What are the indications of thyroidectomy in pregnancy?
It’s safe
1- dysphagia
2- stridor 3- suspected carcinoma
4- allergy to both anti thyroid drugs
What are the causes of thyrotoxicosis?
Graves disease 95%
Toxic multinodular goitre
Toxic thyroiditis
Carcinoma
Subacute thyroiditis
Amiodaron/ lithium
What serious maternal side effect of thionamide ( carbimazol- ptu-..) require immediate discontinuation of therapy?
Granulocytosis
( fever- sore throat)
What is the major potential fetal complication of thionamide therapy during pregnancy?
Hypothyroidism
List potential maternal side effects of PTU that occur in the first few months of therapy?
1- fever
2- sore throat
__________________ stop medication
__________________( granulocytosis)
3- unusual bruising
4- bleeding - leukopenia
5- nausea/vomiting
6- abdominal pain
7- headache
8-hepatotoxicity- thrombocytopenia
9- skin rash
10 - arthritis
What is the specific potential complication may occur in the offspring of a woman using methimazole during pregnancy?
**Aplasia cutis ( usually in the scalp)
* esophageal atresia
In what situations B blockers are indicated in patients who are hyperthyroid?
Thyroid storm
For rapid control of symptoms
What are the potential fetal or neonatal complications
of long term B blockers use?
IUGR
Neonatal bradycardia
Neonatal hypoglycemia
What is the mechanism of action of
- PTU
- methemazole
PUT : inhibits conversion of T4 into T3
Dose 50- 150 mg
Methimazole: inhibits thyroid peroxidase… inhibits the synthesis of T4
Dose loading: 10- 20 mg
Maintenance: 5-10 mg
What fetal complications might occur if maternal hyperthyroidism untreated?
1- increased perinatal mortality
2- fetal tachycardia/heart failure
3- hearing loss
4- hyper/ hypothyroid with/ without goitre
5- preterm labour
6- IUGR
**7- non immune HYDROPS
