Chapter 31 ENDOCRINE Flashcards
Differentiate primary, secondary, and tertiary endocrine disorders.
Primary - originate in the target gland responsible for producing the hormone.
Secondary disorders - target gland is normal but function is altered by defective levels of stimulating hormones or releasing hormones from the pituitary system
Tertiary - hypothalamic dysfunction
Discuss the effects of pituitary tumors
- usually benign
- adenoma most common type
- adenoma can be divided into nonfunctional and functional tumors that secrete pituitary hormones
- usually endocrine abnormalities related specifically to functional adenomas and local mass effects of the expanding tumor
- intracranial pressure, headache, nausea, vomiting. seizures, hemorrhage.
Describe the clinical features and causes of hypopituitarism.
CAUSES
-Congential
Benign tumor compressing pituitary gland
Radiation
MANIFESTATION
-loss of GH, LH, FSH, TSH, and ACTH, and PROLACTIN.
-ACTH deficiency leads to weakness, nausea, anorexia, fever, and postural hypotension
Compare the causes and effects of three types of childhood growth hormone deficiency.
IDIOPATHIC SHORT STATURE
- unknown cause
- > 2 standard deviation below normal mean height for age, sex and population
PSYCHOSOCIAL DWARFISM
-emotional deprivation
GH deficiency
-lack of GHRH
-lack somatotropes
decreased birth length and growth
Discuss the result of growth hormone deficiency in adults.
- present in childhood or adulthood turmor
- somatopause: GH decline with age
MANIFESTATION
- decrease in lean body mass and increase in fat mass (hyperlipidemia)
- reduce exercise tolerance
- decreased bone density
CVS: central adiposity, insulin resistance.
Compare growth hormone excesses in children and adults.
GH EXCESS IN CHILDREN
-Gigantism
Rare, due to adenoma
Prior to puberty
Epiphyses of long bone aren’t fused
Manifestations
Excessive skeletal growth
Recognized early and treated
ACROMEGALY
Adenoma secreting GH, often benign
After puberty when epiphyses has fused
Small bone growth
Fingers, hands, toes, jaw, forehead
Kyphosis, arthralgia, degenerative arthritis
Soft tissue/cartilage growth
Nose, larynx, respiratory tract
Deep voice, risk of bronchitis, sleep apnea
Paresthesis (nerve compression)
Explain the condition known as precocious puberty
- Early activation of hypothalamus, pituitary and gonadal hormones causing early emergence of secondary sexual characteristics and fertility
- girls <9
CAUSES
-Idiopathic
CNS tumor
Gonadal, adrenal, hypothalamic disorder
TREATMENT
-long acting GnRH agonist
Describe the hypothalamic-pituitary-thyroid feedback system.
thyrotropin-releasing hormone (TRH), in the hypothalamus, controls the release of TSH from the anterior pituitary gland. TSH then stimulates the thyroid to produce thyroid hormones. Increased levels of thyroid hormone act in the feedback inhibition of TRH or TSH.
Describe tests in the diagnosis and management of thyroid disorders
- diagnosis of hypothyroidism is based on history, physical examination, and lab test.
- low serum T4 and elevated TSH levels
- hypo is treated by replacement therapy of T3 and T4
- hyper is treated with reducing the level of thyroid hormone. Surgical or drugs
Relate the functions of thyroid hormone to hypothyroidism and hyperthyroidism
-abnormal thyroid hormone or deficient TSH secretion in hypothyroidism
- high level of circulating thyroid hormones in tissue
- thyroid hormone may heighten the sensitivity of the body to the catecholamines.
Describe the causes of primary versus secondary hypothyroidism
CAUSE of PRIMARY
- thyroidectomy
- radiotherapy with iondine
- iondine deficiency
- HASHIMOTO
- CRETINISM
CAUSE OF SECONDARY *-Infection Inflammation Infiltration Hemorrhage Tumor
-impaired pituitary function
In rare instances, usually due to a tumor, the pituitary gland will fail to produce thyrotropin (TSH), the hormone that stimulates the thyroid to produce its hormones. In such cases, the thyroid gland withers. When this happens, secondary hypothyroidism occurs.
Describe Hashimoto’s thyroidosis
Most common hypothyroidism Autoimmune Lymphocytic infiltration of thyroid gland Women more than men Manifestation Goiter
Describe Cretinism
-Congenital
Appear normal at birth d/t Mom’s hormones
1st sign: prolongation of physiologic jaundice
If treated, minimal symptoms
If untreated Enlarged tongue: hoarse cry, difficulty feeding Enlarged abdomen, umbilical hernia Sluggishness, mental retardation Impaired physical growth
Causes, manifestations and treatment of myxedematous coma
- cold exposure
- severe hypothyroidism
- Non-pitting mucous type of edema d/t accumulation of mucopolysaccharide substance throughout connective tissue
- unable to metabolize sedatives, analgesics, and drugs which leads to coma
MANIFESTATION -life-threatening Resp: CO2 retention, hypoxemia CVS/Renal: Fluid/electrolyte imbalance CNS: Hypothermia
TREATMENT
-support cardiorespiratory status, hyponatremia, hypoglycemia and thyroid replacement therapy
Causes, manifestations and treatment of thyroid storm
-rare, risk is hyperthyroidism CAUSE -infection -diabetic ketoacidosis -physical or emotional trauma -thyroid stimulation during surgery
MANIFESTATION
- high fever
- tachycardia, angina, heart failure
- agitation, restlessness, and delirium
TREATMENT
- beta blocker
- meds to decrease circulating TH
- surgical removal
