Thyroid disorders

1.  1. Goitre
 Is an enlargement of the thyroid gland
 May be congenital or acquired
 Thyroid function may be normal –euthyroid
 Underactive – hypothyroid
 Overactive – hyperthyroidism
 Enlargement is usually 2° to ↑sed pituitary
secretion of TSH but may in certain cases, be
due to an infiltrative process that may be
either inflammatory or neoplastic

2.  The commonest causes are due to
transplacental transmission of factors that
interfere with fetal thyroid fxn from the
mother to the fetus
 Maternal antithyroid drugs
 Maternal iodine exposure
 Maternal hyperthyroidism ( grave’s d’se)
 Others– thyroid teratoma, endemic iodine
def., thyroid hormone biosynthesis defect

3.  Is simple euthyroid
 Multinodular
 Acute thyroidism
 Grave’s dse
 Antithyroid chemical exposure.
 Iodine intoxication
 Anti- thyroid drugs:

4.  Hypothyroidism
Is rare in children
1 in 4000 infants
Is a serious threat to mental development
Affects newborns and children

5.  Occurs when there is insufficient secretion of
thyroid hormone
 Present from birth
 Is the most common – 90% of all the infant
hypothyroidism
 Occurs when part of the fetal thyroid system
fails to develop correctly . Sometimes the
gland do not descent fully into the proper
place.
 Or thyroid underdevelopment

6.  Athyrosis – absent gland
Transient hypothyroidism
10% of cases is temporary
Usually because the mother has been treated
of grave’s disease or hyperthyroidism
It can last from days to months

7.  Children and adolescents are affected
 Is an autoimmune thyroid disease e.g.
Hashmoto’s disease
 Is common at puberty and in girls than boys
Diagnosis
 HighTSH & low thyroxine 4 is
hypothyroidism
 PKU-- Phenylketonuria diagnostic of
galactoseamia

8.  X-ray of the bones– end of bones appear
underdeveloped
 Scan of the thyroid gland– will show
malformed, improperly located or absent
thyroid gland

9.  Puffy face
 Swollen tonque
 Hoarse cry
 Cold extremities
 Mottled skin
 Poor feeding
 Thick coarse hair that goes low on the
forehead, large fontanel
 Prolonged jaundice, poor feeding, cons

10.  Umbilical hernia
 Lethergic – sleeps most of the time
 Persistent consitpation, bloated or full to
touch
 Low body temperatures
 Poor development
 Permanent mental retardation
 IQ is below 80
 ADHD (attention deficit hyperactivity
disorder) in older children

11.  Oral thyroxine ( evothyroxine)
 Dose 10-15 micro gram/ kg daily
 Ensure normal growth & devpt
Prognosis
 Treatment is cheap, simple, and available.
Most of them recover fully
 Cretinism is an old term for the state of
mental and physical retardation resulting
from hypothyroidism due to iodine deficiency

12.  Thyrotoxicosis refers to the clinical
physiological and biochemical findings that
result when tisssues are exposed to excess
thyroid hormones
 Causes
 Excess thyroid stimulation
 Grave’s disease,
 neonatal thyrotoxicosis
 Pituitary thyroid hormone resistance

13.  Hyperactivity
 Poor concentration, altered mood, insomnia
 Heat intolerance
 Weight loss
 Diarrhoea
 Menstrual irreqularities
 Hyper pyrexia

14.  Is a complex autoimmune disorders with both
genetic and environmental factors
contributing to susceptibility.
 Clinical features
Diffuse goitre
Exophthalmos
Ptosis
Eye lid lag

15.  Thyroid function test – HighT3 &T4 and low
TSH
 Thyroid antibody screen
TREATMENT
 Antithyroid drugs –carbimazole or
propylthioracil –for 12 to 24 months
 propranolol

16.  The adrenal gland is composed of 2
endocrine tissues:
 the medulla and
 the cortex
 Cortisol deficiency decreases negative
feedback on the hypothalamus and
pituitary, leading to increased secretion of
ACTH

17.  1° adrenal insufficiency may be caused by
genetic conditions that are not always
manifested in infancy and by acquired
problems such as autoimmune conditions.

18.  inborn errors of steroid biosynthesis,
 sepsis,
 adrenal hypoplasia congenita, and
 adrenal hemorrhage.

19.  Primary adrenal insufficiency leads
to cortisol and often aldosterone
deficiency.
 Adrenal insufficiency presents with
 Hypoglycemia
 ketosis.
 Ketosis is aggravated by anorexia,
nausea, and vomiting,

20.  Hyperkalemia,
 hyponatremia, and
 hypoglycemia are prominent presenting signs
of adrenal insufficiency in infants.
 Ketosis is not consistently present because
infants generate ketones less well than do
older children.
 Hyperpigmentation usually takes weeks or
months to develop, and
 orthostatic hypotension is difficult to
demonstrate in infants.

21.  Cortisol deficiency -:
 decreases cardiac output and vascular
tone; catecholamines such as epinephrine
have ↓ inotropic and pressor effects in
the absence of cortisol.
 manifested as orthostatic hypotension &
shock

22.  Aldosterone deficiency, →
 hypovolemia.
 Hypotension and decreased cardiac
output
 hyponatremia.
 hyperkalemia

23.  The onset is usually more gradual and is
characterized by muscle weakness, malaise,
anorexia, vomiting, weight loss, and orthostatic
hypotension.
 Hyperpigmentation is often but not necessarily
present.
 Hypoglycemia and ketosis are common, as is
hyponatremia.
 Hyperkalemia tends to occur later in the course
of the disease in older children than in infants.
Thus, can be easily confused with gastroenteritis
or other acute infections.

24.  Salt craving is seen in primary adrenal
insufficiency with mineralocorticoid
deficiency.
 Fatigue, myalgias, fever, eosinophilia,
lymphocytosis, hypercalcemia, and anemia
may be noted with glucocorticoid deficiency

25.  Hypoglycemia, ketosis, hyponatremia,
and hyperkalemia .
 An electrocardiogram is useful for
quickly detecting hyperkalemia in
critically ill Acidosis is frequently
present, and the blood urea nitrogen
level is elevated if the patient is
dehydrated.

26.  Iatrogenic secondary adrenal insufficiency (caused
by chronic glucocorticoid administration) is best
avoided by use of the smallest effective doses of
systemic glucocorticoids for the shortest period of
time.
 Patients with anatomic lesions of the pituitary
should be treated indefinitely with glucocorticoids.
Mineralocorticoid replacement is not required.
 In patients with panhypopituitarism treating
cortisol deficiency may cause freewater excretion
thus unmasking central diabetes insipidus.

27. CAH is an autosomal recessive
disorders of cortisol biosynthesis
Cortisol deficiency increases secretion
of corticotropin (ACTH), which in turn
leads to adrenocortical hyperplasia
and overproduction of intermediate
metabolites.

28. Depending on the enzymatic step that is
deficient, there may be signs, symptoms,
and laboratory findings of
mineralocorticoid deficiency or excess;
incomplete virilization or premature
puberty in affected males; and virilization
or sexual infantilism in affected females

29.  is the result of abnormally high blood
levels of cortisol or other glucocorticoids.
This can be iatrogenic or the result of
endogenous cortisol secretion, due either
to an adrenal tumor or to hypersecretion of
corticotropin (adrenocorticotropic
hormone [ACTH]) by the pituitary (Cushing
disease) or by a tumor

30.  Bilateral adrenal
hyperplasia Hypersecretion of
corticotropin (Cushing disease) Ectopic
secretion of corticotropin Exogenous
corticotropin Adrenocortical nodular
dysplasia Pigmented nodular
adrenocortical disease (Carney complex)
Tumor Carcinoma Adenoma

31.  May be as early as 1 year
 The face is rounded, with prominent cheeks and a
flushed appearance (moon facies). Generalized
obesity .
 In children with adrenal tumors, signs of
abnormal masculinization occur frequently;
 there may be hirsutism on the face and trunk,
 pubic hair,
 acne,
 deepening of the voice, and
 enlargement of the clitoris in girls.

32.  Growth is impaired, with length ˂ 3rd percentile,.
 Hypertension is common & may → heart failure.
 An ↑ susceptibility to infection →fatal sepsis.
 In older children - Pubertal development may be
delayed, or amenorrhea in girls past menarche.
 Weakness, headache, and emotional lability may
be prominent.
 Hypertension and hyperglycemia usually occur;
 hyperglycemia may progress to frank diabetes.
 Osteoporosis is common, →pathologic fractures.

33.  Cortisol levels in blood are normally elevated at 8
A.M. and decrease to less than 50% by midnight
 Elevated nighttime salivary cortisol levels
 Urinary excretion of free cortisol is increased.
 A single-dose dexamethasone suppression test is
often helpful; (a dose of 25–30 μg/kg (maximum
of 2 mg) given at 11 P.M. results in a plasma
cortisol level of less than 5 μg/dL at 8 A.M. the
next morning in normal individuals but not in
patients with Cushing syndrome.

34.  A glucose tolerance test is often abnormal
despite elevated levels of insulin.
 Levels of serum electrolytes are usually
normal, but potassium may be decreased,
especially in patients with tumors that
secrete ACTH ectopic

35.  1. Obesity, Children with simple obesity are
usually tall, whereas those with Cushing
syndrome are short or have a decelerating
growth rate.
 2. generalized glucocorticoid resistance.
Affected patients may be asymptomatic or
exhibit hypertension, hypokalemia, and
precocious pseudopuberty; these
manifestations are caused by increased
mineralocorticoid and adrenal androgen
secretion in response to elevated ACTH levels.
 3. Pituitary adenoma

36.  Transsphenoidal pituitary microsurgery is the
treatment of choice in pituitary Cushing
disease in children.
 success rate with follow-up of less than 10 yr is
60–80%.
 Low postoperative serum or urinary cortisol
concentrations predict long-term remission in
the majority of cases.
 Relapses are treated with re-operation or
pituitary irradiation.

37.  Cyproheptadine, a centrally acting
serotonin antagonist that blocks ACTH
release, has been used to treat Cushing
disease in adults; remissions are usually not
sustained after discontinuation of therapy.
This agent is rarely used in children.
 If a pituitary adenoma does not respond to
treatment laparoscopically do
Adrenalectomy

38.  sepsis,
 pancreatitis,
 thrombosis,
 poor wound healing, and sudden collapse,
particularly in infants with Cushing
syndrome.
 increased bone density occur, but bone
density remains abnormal and adult height
is often compromised.

39.  Pheochromocytomas, catecholamine-
secreting tumors, arise from chromaffin
cells.
 90% arise from the adrenal medulla;
however, tumors may develop anywhere along
the abdominal sympathetic chain and are
likely to be located near the aorta at the
level of the inferior mesenteric artery or at
its bifurcation.

40.  Pheochromocytoma may be inherited
as an autosomal dominant trait. In
affected families, the ages of patients
at the time of diagnosis have varied
from the 1st to 5th decades of life;
 more than half the patients have had
multiple tumors.
 Pheochromocytomas may also be
associated with other syndromes such

41.  Result from excessive secretion of
epinephrine and norepinephrine.
 All patients have hypertension at some time.
 The hypertension in children is more often
sustained rather than paroxysmal, in contrast
to adults.
 During attacks, the patient complains of
headache, palpitations, abdominal pain, and
dizziness; pallor, vomiting, and sweating also
occur.

42.  In severe cases, precordial pains radiate
into the arms; pulmonary edema and
cardiac and hepatic enlargement may
develop.
 Symptoms may be exacerbated by
exercise.
 The child has a good appetite but
because of hypermetabolism does not
gain weight, and severe cachexia may

43.  Growth failure may be striking.
 The blood pressure may range from 180 to
260 mm Hg systolic and from 120 to 210
mm Hg diastolic, and the heart may be
enlarged.
 Ophthalmoscopic examination may reveal
papilledema, hemorrhages, exudate, and
arterial constriction.

44.  The urine may contain protein, a few casts,
and occasionally glucose.
 Gross hematuria suggests that the tumor is
in the bladder wall. Polycythemia is
occasionally observed.
 The diagnosis is established by
demonstration of elevated blood or urinary
levels of catecholamines and their
metabolites.

45.  Various causes of hypertension in children
must be considered, such as
 renal or renovascular disease;
 coarctation of the aorta;
 hyperthyroidism;
 Cushing syndrome;
 Neuroblastoma,
 ganglioneuroblastoma, and ganglioneuroma
frequently produce catecholamines.
 Secreting neurogenic tumors

46.  Removal of these tumors results in cure, but
the operation is very high risk.
 Careful preoperative, intraoperative, and
postoperative management is essential.
Preoperative α- and β-adrenergic blockade
and fluid loading are required.
 Because these tumors are often multiple in
children, a thorough transabdominal
exploration of all the usual sites offers the
best opportunity to find them all.

47.  Appropriate choice of anesthesia and
expansion of blood volume with appropriate
fluids during surgery are critical to avoid a
precipitous drop in blood pressure during
operation or within 48 hr postoperatively.
 Manipulation and excision of these tumors
result in marked increases in catecholamine
secretion that increase blood pressure and
heart rate. Surveillance must continue
postoperatively.