pediatric endocrinology

1. Diseases in endocrine system
Yao Xiaoli
（姚孝礼）
Endocrine department in the first
hospital
Xi’an Jiao Tong University

2. General consideration

3. Contents
• Definition
• Development
• Hormones
• Mechanisms of hormone action
• Modulation of endocrine function
• Diagnosis principles of endocrine
disorders
• Treatment

4. Definition:
Endocrine system :
• A humoral modulating system,
• consisted of endocrine glands,
endocrine tissues and hormone,
• control the metabolic process,
• maintain the homeostasis.

5. • Hormones: Chemicals that travel
through the blood and induce cellular
responses in target tissues via receptors.
• Receptors: Proteins in target tissue cells
that bind hormone at one site and initiate
cellular response。

6. Endocrine glands:
hypothalamus, pituitary, thyroid, parathyroid,
islets, adrenal glands, ovary and testis.
Endocrine tissue:
endothelium, lipocyte.
Nerve-endocrine cells:
APUD cells in digest tract.

8. Development:
1. Endocrinology on organ
In this period people’s knowledge of
endocrinology only limited to clinical
manifestations and mass pathology
changes.

9. 2. Endocrinology on tissue
Dr. Yallow developed Radioimmuno-
assay that makes the detection of minim
hormones possible.

10. 3. Endocrinology on molecule
Study on gene expression, mutation,
e.g. artificial synthesis of growth hormone
and insulin by gene recombinant
technique.

11. Classification
• Amino hormones-derived from tyrosine:
CA, TH
• Peptide and protein hormones-encoded in
genes: TRH, INS
• Steroid hormones-derived from cholesterol:
F, Ald, T, E, P
Hormone

12. Secretory rhythm
• Biological rhythm:
FSH, LH
E2 P
Delivering
ovum (day)
menses
LH &
FSH
P E2

13. •Diurnal rhythm: ACTH

14. GH
hour

15. From: hypothalamus
1.Gonadotropin releasing hormone (GnRH),
2. Thyroid stimulating hormone releasing
hormone (TRH),
3. Corticotrophin releasing hormone (CRH) ,

16. 4. Growth hormone releasing hormone
(GRH) ,
5. Somatostatin (SS),
6. Prolactin releasing factor (PRF),
7. Prolactin inhibiting factor (PIF).

17. From anterior pituitary
1. Follicle stimulating hormone (FSH),
2. Luteinizing hormone (LH) ,
3. Thyroid stimulating hormone (TSH) ,
4. Adrenocorticotropic hormone (ACTH) ,
5. Growth hormone (GH) ,
6. Prolactin (PRL).

18. From posterior pituitary
1. Arginine vasopressin (AVP=ADH) ,
2. Oxytocin (OXT).

20. From peripheral glands
• Thyroid:
T4 and T3
• Adrenal cortex:
cortisol ,
aldosterone
• Adrenal medulla:
epinephrine (E),
norepinephrine (NE)

21. Ovary :
progesterone ,
estradiol
Testis :
testosterone
Parathyroid :
parathyroid hormone (PTH)
Pancreatic islets:
insulin ,
glucagon

22. Hypothalamus: CRH GnRH TRH GHRH SS PRF PIF ADH OXT
Pituitary : ACTH LH, FSH TSH GH PRL ADH OXT
Target gland F E2, P, T T3,T4
(stored here)
(producted here)
+ + + + _ + _
+ + +
adrenal
gland
ovary,
testis
thyroid
Hypothalamus– pituitary—target gland axis

24. Mechanisms of hormone action
1. Membrane receptor:
ACTH, LH, FSH,PTH,
cAMP, DAG, IP-3, and Ca

26. 2. Nucleus receptors
Others such as steroid hormones,
thyroid hormones, which are lipid-soluble
hormones, can penetrate through cellular
membrane and bind at specific receptors
located on the cell nucleus and exert their
action.

28. Ⅳ. Modulation of endocrine
function
1. Inter-modulation between nervous system
and endocrine system.
The central nervous system exerts
profound regulatory control over hormonal
secretion and metabolic process. e.g.
(1) Hypothalamus secrete releasing
hormones
(2) Stress can increase the epinephrine
and nonepinephrine

29. 2. Feed back regulation of
endocrine system
• Negative feedback:
e.g. TRH– TSH– T3,T4
• Positive feedback :
e.g. GnRH—FSH,LH— E2(during
delivering ovum)

31. 3. Immune system and endocrine
function
• F, sex hormone, PGE inhibit immune
response.
• GH,T3,T4,INS increase immune response.
• ACTH from not only pituitary but also LC.
• IL-2 increases PRL, TSH, ACTH,
LH,FSH,GH.

32. Ⅴ. Diagnosis principles
1. History and physical examination:
• excessive Growth and Delayed growth:
GH, TH, Sex hormone
• obesity and Wasting :
GH, INS, F
• polyuria and polydipsia :
DM, Aldosteronism, diabetes insipidus
(Ⅰ) Functional diagnosis

33. • hypertension with hypokalemia:
Ald, F, Renin
• skin pigmentation:
ACTH
• hirsutism:
T
• purple striae and acne:
F, T
• gynaecomastia:
E

34. • exophthalmos:
GD
• galactorrhea and amenorrhea:
PRL
• pathologic fracture:
osteoporosis

53. (1). Measurement of hormone: INS, F, T3,
T4, GH, VMA, NE, N, CA, 17-OH,
17-KS, ALD…
(2). Metabolic abnormality: K, Ca, Na, BS,
blood gas…
2. Lab. test:

54. (3). Dynamic testing
a. Provocating test
It stimulates the decreased hormone to
make sure if it is really decreased and to
know the functional reserve.
for hypofunction.
e.g. TRH stimulating test for confirming
hypothyroidism.

55. b. Suppression test
It is used to suppress the elevated
hormone to know if it has any response to
exogenous hormone.
for hyperfunction.
low-dose dexamethasone
suppression test for confirming Cushing
syndrome.

56. (Ⅱ)Localization/pathological diagnosis
X-ray, ultrasound, CT, MRI, nucleus scan,
Catheter sampling, angiography to find the site
of lesion
Pathology examination
Fine needle aspiration of thyroid gland
confirms etiology.

57. (Ⅲ) Diagnosis of etiology
• Chemistry:
e.g. lack of iodine in urine endemic
goiter
• Immunology:
ICA T1 DM
TRAb GD
TPOAb Hashimoto’s
TgAb disease
ICA(+)
H.E

58. • Chromosome and gene:
47XXY Klinefelter syndrome,
45XO Turner syndrome

59. Thyroid scan with 99mTc
in graves’ disease

60. Thyroid scan in
Subacute thyroiditis
Thyroid scan in
Hashimoto’s
thyroditis

63. Ⅵ. Treatment
1. Etiology:
supply of lack of element,
2. Hypofunction
(1) Hormone replacement, (2) medicine,
(3) transplantation

64. 3. Hyperfunction
(1) Surgery
(2) Medicine
(3) Nuclei
(4) Radiotherapy
(5) Catheter

66. Thanks