Flashcards in Endocrine pathology Deck (47):
What is the difference between hyperplasia & adenoma of a gland?
Hyperplasia implies an excess of stimulating hormone, while adenomas arise independently
* Hyperplasias are almost always functional, while adenomas response to regulatory hormones vary
* Carcinoma are the least functional and usually independent of regulatory hormonal influence
the most common pituitary tumor in children, arises from remnants of Rathke pouch. Malignancy is rare
* There is visual field abnormalities and diabetes insipidus
Define Prolactinoma, and what are its effects on men and women?
The most common adenoma of the anterior pituitary
* There is excess production of prolactin
* Men: galactorrhea & infertility
* Women: Galactorrhea & amenorrhea
A pituitary tumor impinging on the optic chiasm will produce ......
What are the medical complications that are associated with acromegaly?
DM, Hypertension, osteoporosis, and other space occupying lesions
What are the clinical features of Diabetes insipidus?
Polyuria (even at dehydration) and polydipsia, high serum osmolality, hypernatremia
* Central DI respond to ADH therapy, nephrogenic doesn't
Patients taking steroids are prone to infection. T/F??
What are the four types of Cushing syndrome?
1. Pituitary cushing: 2/3 of cases of cushing. There is pituitary adenoma, high ACTH and bilateral adrenal hyperplasia. Also called cushing disease
2. Adrenal cushing: Low ACTH , adrenal adenoma
3. Ectopic cushing: cancers (usually bronchogenic) producing ectopic ACTH
4. Iatrogenic: results from exogenous steroids or ACTH
Addison's disease (primary adrenal insufficiency) is characterized by ......
low level of cortisol, androgen and aldosterone, weight loss, hypoglycemia, hypotension, skin pigmentation, inability to tolerate stress, abdominal pain
* Lab work shows: low Na & Cl, low cortisol, high K, metabolic acidosis, high ACTH (with pigmentation)
What are the clinical feature of adrenal adenoma?
Usually asymptomatic and nonsteroid producing
* On the other hand, adrenal carcinoma (rare) is steroid producing tumor
Pheochromocytoma is ...... and the clinical features are ....
neoplasm of neural crest derived chromaffin cells that secrets catecholamines
* Constant hypertension, sweating, headache, arrhythmias, palpitations, nervousness
Define Neuroblastoma and what are its clinical features?
neuroendocrine tumor derived from neural crest, usually in the adrenal medulla, and is the most common extracranial cancer in children
* Rapidly growing tumor that metastasizes widely especially to the bone and produce catecholamines. Occurs in the medulla, but may occur anywhere along the sympathetic chain
Why diagnosis of hyperthyroidism is difficult in pregnancy? And how is it diagnosed?
Because pregnancy is a hypermetabolic state by itself, and there is thyromegaly. Also, TBG is elevated due to high estrogen.
* In this case, diagnosis is by measuring free T4. Note that total serum T4 is elevated (includes free and TBG bound hormone)
What are the clinical features of hyperthyroidism?
1. Cardiac: tachycardia, palpitations, cardiomegaly, cardiomyopathy, atrial fibrillation
2. Peripheral: skin warm, moist and flushed, increased sweating, heat intolerance, weight loss, tremor
* Diagnosis is by high T4
* There is generalized osteoporosis
What are the main causes for hypothyroidism?
1. Low TSH
2. Thyroid hypoplasia or dysplasia
3. Hashimoto thyroiditis, low Iodine
4. Peripheral resistance to thyroid hormones
5 Radiation destruction of the gland
Low thyroid hormone in infants causes ....., which is characterized by ....
* Characterized by:
1. Skeletal defects: short stature, wide set eyes, broad nose, delayed epiphyseal closure.
2. Mental retardation, somnolence
3. Constipation, feeding difficulties, failure to thrive
* Early diagnosis must be made by detecting high TSH
* Same symptoms for older children, but lesser severity
Hyperthyroidism is associated with increased atherosclerosis and serum cholesterol. T/F??
* Hypothyroidism is
Graves disease is more common in ....., and is associated with .....
women (5x more) than men
* Associated with Hashimoto disease and pernicious anemia
In Graves disease, there is overstimulation of TSH receptors by ...... & ......
thyroid growth immunoglobulin
Thyroid stimulating immunoglobulin (TSI)
What are the clinical features of Graves disease?
3. Dermopathy: nodules or plaques on the lower extremities
Diffuse non toxic goiter is ......,
What are the types of non toxic goiter?
enlargement of the thyroid in euthyroid patients (normal)
1. Endemic: due to low iodine or goitrogens (fluoride, calcium)
2. Sporadic simple goiter: more in women
* There is low thyroid function
Ectopic thyroid nests are found at ......
Thyroglossal duct or cyst is ......
* Base of the tongue
* Communication between thyroid and base of tongue, due to incomplete descend of thyroid tissue
Thyroid follicular adenoma is ......
most common tumor of thryoid
* There is pain, pressure symptoms, but rarely thyrotoxicosis
Parathyroid adenoma usually involves ......., while parathyroid hyperplasia involves ......
all four glands (hyperplasia of chief cells)
What is the difference between primary and secondary hyperparathyroidism??
1. Primary: adenoma or hyperplasia of the parathyroid
2. Secondary: renal failure, leading to low Ca, which in turn increases PTH
Hypoparathyroidism is characterized by ......
The clinical features are .....
hypocalcemia, hyperphosphatemia, tetany, intracranial calcification, lens calcifications, dental abnormalities, cardiac conduction defect, muscular hyper excitability
* short stature, shortened fourth and fifth carpals and metacarpals
Define Hypercalcemia, and what are the causes
persistent serum Ca over 10.4 mg/dL
* Caused by: Malignancy, Vit D intoxication, sarcoidosis, hyperparathyroidism, Alkali syndrome, Paget disease
* Note that at 6 mg/dL tetany occurs. Below this level it could be lethal
What are the clinical features of hypercalcemia?
renal stones, hypercalciuria, hypophosphatemia
* ALP is usually elevated
Why there is no (or low) ketoacidosis in type 2 diabetes?
because its level is related to glucagon level. Type 2 has a high level of insulin with low glucagon
* Type 1, there is low insulin, and so glucagon levels rise, subsequently, ketoacidosis increases
What are the possible causes of type 1 diabetes?
1. Viral: coxsackievirus B, CMV, mononucleosis, rubella
2. genetic predisposition
3. Autoimmune response (anti islets cell bodies)
* Type 2 is usually has a genetic predisposition
The lab work for a diabetic patient shows ......
hyperglycemia, hyperlipidemia, glycosuria
The high level of glucose in urine leads to .....
dehydration, via osmotic diuresis
Hyperosmolar nonketotic coma is ......
coma when blood sugar exceeds 600mg/dL
What are the long term complications of diabetes??
1. Atherosclerosis, hypertension
2. Nephropathy: proteinuria & edema
3. Neuropathy: distal symmetric polyneuropathy involving the PNS.
5. Kimmelstiel-Wilson syndrome
There is a much higher mortality from ...... dependent diabetes
* NIDDM decreases life span by about 8 years
Beta cell tumor produces .......
hyperinsulinemia, causing hypoglycemia
* There is altered sensorium that is relieved by glucose intake
* The tumors are solitary, well encapsulated adenomas
Nephrogenic diabetes insipidus is a ...... disease
* Men are affected, women pass it to offspring
The HbA1C test measures ......
long term elevated blood glucose
* Reflects glucose level for the last 2-3 months
Which type of diabetes is more prevalent?
* Patients in this category are generally overweight adults, unlike type 1
Glycosuria occurs when blood glucose level is ..
over 160 mg/dL
In Acromegaly, long bones are elongated. T/F??
* Bones are deformed, since the growth end plates are fused
* There is offensive body odor, perspiration, deep voice, prognathia
What are the dental findings in hyperthyroidism?
premature eruption of teeth with early loss of deciduous dentition
* The opposite is true for hypothyroidism
What are the main symptoms of hyperparathyroidism??
"Bones, Stones, Moans, Groans"
1. Bone lesions
2. Kidney stones
4. Peptic ulcers
* Hyperparathyroidism is associated with MEN type I and II
1. Trousseau's sign
2. Chvostek's sign
These are tests for hypocalcemia and tetanty
1. Blood pressure cuff applied to arm for 3 mins. There will be carpopedal spasm (thumb abduction, the rest are extended)
2. Tapping of facial nerve above the mandibular angle. The upper lip twitches
How is the administration of exogenous ACTH help determines the type of adrenal insufficiency?
1. If the cortisol base level increases by a very small amount, it indicates that the adrenal is non functioning (primary insufficiency)
2. If the serum cortisol base line is doubled or tripled, this indicates that the adrenal are OK (secondary insufficiency)
* Either way, the treatment is cortisol administration
Trousseau sign (syndrome)
The presence of successive tender nodules in the affected veins due to hypercoagulability caused by some tumors (like lung cancer)