Endocrine Charts Pandian M. DEPT OF PHYSIOLOGY D. Y. PATIL MEDICAL COLLEGE, KOLHAPUR
• Dwarfism. • Dwarfism is a pituitary disorder in children, characterized by the stunted growth. • Hypoactivity of anterior pituitary • It Dwarfism may be due to endocrinal or non- endocrinal causes. • Endocrinal causes of dwarfism are: • Growth hormone deficiency (pituitary dwarf), • Panhypopituitarism, • Hypothyroid dwarf and Cushing’s syndrome
•Non-endocrinal causes of dwarfism include: •Familial dwarfism, •Achondroplasia, •Nutritional (malnutrition or malabsorption), •Chromosomal abnormalities, e.g. Turner’s syndrome and •Psychological dwarfism (Kasper–Hauser’s syndrome).
• Causes:- • Reduction in GH secretion in infancy or early childhood Causes dwarfism. • It occurs because of the following reasons: • Tumor of chromophobes: It is a non-functioning tumor, which compresses and destroys the normal cells secreting GH. • It is the most common cause for hyposecretion of GH, leading to dwarfism ii. Deficiency of GH-releasing hormone secreted by hypothalamus iii. Deficiency of somatomedin C iv. Atrophy or degeneration of acidophilic cells in the anterior pituitary • Panhypopituitarism: In this condition, there is reduction in the secretion of all the hormones of anterior pituitary gland.
• II. Signs and symptoms:- • Stunted skeletal growth • The proportions of different parts of the body are almost normal. • Reproductive function is not affected, if there is if there is only GH deficiency. • During panhypopituitarism, the dwarfs do not obtain puberty due to the deficiency of gonadotropic hormones.
• Acromegaly is the disorder characterized by the enlargement, thickening and broadening of bones, particularly in the extremities of the body. • Acro – Peripheral part • Megaly – Enlargement • Causes:- • Acromegaly is due to hypersecretion of GH in adults • after the fusion of epiphysis with shaft of the bone. • Hypersecretion of GH is because of tumor of acidophil cells in the anterior pituitary.
•II. Signs and symptoms:- i. Acromegalic or gorilla face: Face with rough features such as protrusion of supraorbital ridges, broadening of nose, thickening of lips, thickening and wrinkles formation on forehead and prognathism (protrusion of lower jaw) ii. Enlargement of hands and feet iii. Kyphosis (extreme curvature of upper back –thoracic spine)iv. Thickening of scalp. Scalp is also thrown into folds or wrinkles like bulldog scalp v. Overgrowth of body hair
vi. Enlargement of visceral organs such as lungs, thymus, heart, liver and spleen vii. Hyperactivity of thyroid, parathyroid and adrenal glands viii. Hyperglycemia and glucosuria, resulting in diabetes mellitus ix. Hypertension x. Headache xi.Visual disturbance (bitemporal hemianopia)
• Hyperthyroidism – Increased secretion of thyroid hormones is called hyperthyroidism. • • Causes of Hyperthyroidism:- • Graves’ disease or toxic goitre or thyrotoxicosis is the most common cause of hyperthyroidism. • It is an autoimmune disease • The thyroid-stimulating antibodies (TSAb) against the TSH receptors, also called long acting thyroid stimulator. • These antibodies bind to TSH receptors and mimic TSH action on thyroid growth and hormone synthesis. • The entire thyroid gland undergoes hyperplasia as a result of autoimmune stimulation.
• Signs and Symptoms of Hyperthyroidism:- • Exophthalmos • Toxic goiter • Intolerance to heat • Due to increased BMR caused by excess of thyroxine • Increased sweating due to vasodilatation • Decreased body weight due to fat mobilization • Diarrhea due to increased motility of GI tract • Muscular weakness because of excess protein catabolism • Nervousness, extreme fatigue, inability to sleep, mild tremor in the hands and psychoneurotic symptoms such as hyperexcitability. • Extreme anxiety or worry. • Oligomenorrhea or amenorrhea & Tachycardia and atrial fibrillation
• Investigations:- • Both T3 and T4 plasma levels are elevated. • TSH is low or may become undetectable. • 131 I Uptake is increased, i.e. > 35% at 5 h. • TRs antibodies may be increased > 7 U/1, (N = < 7U/l). • Serum cholesterol is less. • ECG shows tachycardia and arrhythmia. • Ultrasonography of thyroid gland shows diffuse goitre.
• Cretinism • Cretinism is the hypothyroidism in children, characterized by stunted growth. • Also known as infantile hypothyroidism • Causes for cretinism:- • Cretinism occurs due to congenital absence of thyroid gland, genetic disorder or lack of iodine in the diet. • A newborn baby with thyroid deficiency may appear normal at the time of birth because thyroxine might have been supplied from mother. • Unless treated immediately, the baby will be mentally retarded permanently.
• Features of cretinism:- • Sluggish movements and croaking sound while crying. • Stunted growth • The tongue becomes so big that it hangs down with dripping of saliva. • The big tongue obstructs swallowing and breathing. • Guttural breathing that may sometimes choke the baby.
Growth-hormone-related dwarfism • Pituitary dwarfism occurs due to deficiency of GH in early childhood. • Causes :- 1. African pygmies. 2. Laron dwarfism.
Characteristic features:- • Deficiency of GH causes retardation of growth in all parts of the body proportionately. • Consequently, a pituitary dwarf with a chronological age of 20 years has the body structure like that of a normal child of 7–10 years of age. Thus, a pituitary dwarf has following features • Shortness of stature, • Normal mental activity, • Plumpness (fatness), • Immature faces, • Delicate extremities and • Sexual maturity does not occur when associated with the gonadotropin deficiency.
• Infantile hypothyroidism (cretinism). • It occurs when thyroid deficiency occurs during first year of life • Its characterized by mental retardation, marked retardation of growth, • Delayed milestones of development, pot belly, protruding tongue, flat nose, dry skin and sparse hairs. • Radiograph of bone shows delayed bone age. • At adolescence, hypothyroidism is characterized by short stature, • Poor performance at school, delayed puberty and Sexual maturation. • Other features of adult hypothyroidism are present to variable degree. • Treatment:- should be prompt otherwise, mental deficiency will persist.
I. Myxedema (HYPOTHYROIDISM) • Myxedema is the hypothyroidism in adults, • Characterized by generalized edematous appearance. • Hypothyroidism leads to myxedema in adults and cretinism in children. • Causes for myxedema:- • Myxedema occurs due to diseases of thyroid gland, genetic disorder or iodine deficiency. • In addition, it is also caused by deficiency of thyroid-stimulating hormone or thyrotropin-releasing hormone. • Common cause of myxedema is the autoimmune disease called Hashimoto’s thyroiditis, • Its common in late middle-aged women • In most of the patients, it starts with glandular inflammation called thyroiditis caused by autoimmune antibodies. • Later it leads to destruction of the glands.
II. Signs and symptoms of myxedema:- • Typical feature of this disorder is an edematous appearance throughout the body. • It is associated with the following symptoms: 1. Swelling of the face 2. Bagginess under the eyes 3. Non-pitting type of edema, 4. Atherosclerosis 5. Cold intolerance. 6. Depressed hair growth 7. Scaliness of the skin 8. Constipation
Investigations:- •Serum T3 and T4 levels low •Serum TSH levels high in primary and low in secondary hypothyroidism •Serum cholesterol high •Peripheral blood film macrocytic anaemia •Photomotogram—delayed ankle jerk.
•Attitude of hand in carpopedal spasm includes: i. Flexion at wrist joint ii. Flexion at metacarpophalangeal joints •Extension at interphalangeal joints •Adduction of thumb.
• TETANY • Tetany refers to a clinical condition resulting from increased neuromuscular excitability. • Hypocalcemia causes neuromuscular hyperexcitability, resulting in hypocalcemic tetany. • Normally, tetany occurs when plasma calcium level falls below 6 mg/dL from its normal value of 9.4 mg/dL.
• Causes:- • Causes of tetany include: • Hypocalcaemia – Extracellular calcium plays an important role in membrane integrity and excitability. • Hypomagnesaemia – also causes tetany, because magnesium ions are also associated with neuromuscular irritability. • Alkalosis – which reduces ionic calcium, can also produce tetany.
• Mainly three hormones regulate Blood calcium level • Parathormone • 1,25- dihydroxycholecalciferol (Calcitriol) – Thyroid gland • Calcitonin • Source of Calcium – whole milk, low fat milk, cheese, other dairy products, vegetables, other substances such as meat, egg, grains etc.
• Cushing syndrome is a disorder characterized by obesity. • Causes:- • Cushing syndrome is due to the hypersecretion of glucocorticoids, particularly cortisol. • It may be either due to pituitary origin or due to adrenal origin. • If it is due to pituitary origin, it is known as Cushing disease. • If it is due to adrenal origin, it is called Cushing syndrome. • Generally, these two terms are used interchangeably.
• Signs and Symptoms:- • Moon face • Torso • Buffalo hump • Pot belly • Purple striae • Thinning of skin and • Poor wound healing.
• Tests for Cushing Syndrome • i. Observation of external features • ii. Determination of blood sugar and cortisol levels • iii. Analysis of urine for 17-hydroxysteroids. • Treatment for Cushing Syndrome • Treatment depends upon the cause of the disease. • Treatment may include cortisol-inhibiting drugs, surgical removal of pituitary or adrenal tumor, radiation or chemotherapy.
• Goiter in Hypothyroidism – Non-toxic Goiter • Non-toxic goiter is the enlargement of thyroid gland without increase in hormone secretion. • It is also called hypothyroid goiter
• It is classified into two types:- a. Endemic colloid goiter – caused by iodine deficiency b. Idiopathic non-toxic goiter – due to unknown Cause • Thyroid hormone have two major effects • To increase BMR • To stimulate growth in children • On CNS – very essential for development & maintenance of normal functioning of CNS.
Action of TH are:- •On CVS – HR & Force of contraction increases •On RS – thyroxine increases rate and force of resp. indirectly.
Referred :- • Text book of Medical Physiology • Guyton, 13th edition, • Text book of Medical Physiology • Indu khurana, • Text book of Medical Physiology • Vander’s • Text book of Medical Physiology • Sembulingam & • LPR