chapter 46 endocrine dysfunction all elsevier items and derived items © 2014, 2010, 2006, 2002,...

Chapter 46

Endocrine Dysfunction

All Elsevier items and derived items © 2014, 2010, 2006, 2002, Mosby, Inc., an imprint of Elsevier Inc.

Cells Send chemical messages by means of hormones

Target cells or end organs Receive the chemical messages

The environment through which chemicals are transported Blood, lymph, extracellular fluids

Hormones Complex chemical substances

The Endocrine System

2All Elsevier items and derived items © 2014, 2010, 2006, 2002, Mosby, Inc., an imprint of Elsevier Inc.

The Endocrine System (Cont.)


Disorders may be due to organic defects or have an idiopathic cause

Problem may involve a single hormone or a combination of several hormonal deficiencies

Clinical manifestations depend upon the hormone involved

Disorder may result in an overproduction or hormone deficiency

Disorders of Pituitary Function


Deficient secretion of pituitary hormones Inhibits somatic growth and development of

secondary sex characteristics Consequences: depend upon the degree of

dysfunction Gonadotropin deficiency Growth hormone (GH) deficiency Thyroid-stimulating hormone (TSH) deficiency Corticotropin deficiency

Hypopituitarism: Growth Hormone Deficiency


Family history Growth patterns and previous health status Physical examination Psychosocial evaluations Radiographic survey Endocrine studies

Diagnostic Evaluation of Growth Hormone Deficiency


Treatment is directed toward correction of the underlying disease process

Replacement with GH is successful in 80% of affected children

Therapy is ended when growth rates are less than 1 inch per year Girls: at 14 years of age Boys: at 16 years of age

Therapeutic Management of Growth Hormone Deficiency


Identifying and assisting with the diagnosis Child and family support Emotional adjustment of the child Preparation for testing and medication

administration Providing increased attention to child during

testing

Care Management of Growth Hormone Deficiency


Excess GH before closure of epiphyseal shafts results in overgrowth of long bones

Patients can reach heights of 8 feet or more Vertical growth is accompanied by increased

muscle Weight is generally in proportion to height

Pituitary Hyperfunction


Excess GH after epiphyseal closure is called “acromegaly”

Typically, several facial features undergo overgrowth Head Lips, tongue, jaw, nose Paranasal, mastoid sinuses Separation and malocclusion of the teeth

Pituitary Hyperfunction: Acromegaly


History of excessive growth during childhood Evidence of increased levels of GH Radiographic studies

May reveal a tumor Endocrine studies

Diagnostic Evaluation of Pituitary Hyperfunction


Surgical treatment to remove tumor Radiation and radioactive implants Hormone replacement therapy after surgery in

some cases Thyroid extract Cortisone Sex hormones

Therapeutic Management of Pituitary Hyperfunction


Early identification of children with excessive growth rates

Early treatment for improved outcomes Observation for signs of tumor Emotional support Addressing body image concerns

Care Management of Pituitary Hyperfunction


Defined as sexual development before age 9 years in boys or before age 8 years in girls

Evaluation for pathologic cause: required in white girls younger than 7 years and African American girls younger than 6 years

Disorder of gonads, adrenal glands, or hypothalamic-pituitary gonadal axis

Precocious Puberty


Central precocious puberty (CPP) 80% of cases of precocious puberty Early maturation and development of gonads and

secondary sex characteristics Peripheral precocious puberty

Premature development of breasts, pubic and axillary hair, and menses

Types of Precocious Puberty


Treatment of specific cause if known May be treated with leuprolide (Lupron)

Slows prepubertal growth to normal rates Treatment is discontinued at age when normal

pubertal changes are expected to resume Psychologic support for child and family

Therapeutic Management of Precocious Puberty


The principal disorder of the posterior pituitary gland

Results from hyposecretion of antidiuretic hormone (ADH)

Produces uncontrolled diuresis Primary causes: familial or idiopathic Secondary causes: trauma, tumors, central

nervous system infection, aneurysm

Diabetes Insipidus


Cardinal signs: polyuria and polydipsia Infants: irritability relieved with feedings of water

but not milk; dehydration often occurs Diagnosed by reducing fluid intake with little or

no effect on urine output

Clinical Manifestations of Diabetes Insipidus


Instruct parents in difference between diabetes insipidus and diabetes mellitus

Daily hormone replacement Drug of choice: vasopressin (DDAVP)

Nasal spray or intravenous administration Subcutaneous or intramuscular injection Treatment required for life

Therapeutic Management of Diabetes Insipidus


Results from oversecretion by the posterior pituitary gland (increased ADH)

Fluid retention and hypotonicity Kidneys unable to reabsorb water Anorexia, nausea/vomiting, irritability,

personality changes Symptoms alleviated when ADH is decreased

Syndrome of Inappropriate Antidiuretic Hormone (SIADH)


Accurate measurements of intake and output Observation for signs of fluid overload Seizure precautions ADH-antagonizing medications Child and family education

Care Management of SIADH


Thyroid hormone regulates basal metabolic rate Thyroid secretes two types of hormones

Thyroid hormone, which is made up of• Thyroxin (T4)• Triiodothyronine (T3)

Calcitonin Patients may have hypothyroidism or

hyperthyroidism Patients may have disturbance in secretion of

TSH

Disorders of Thyroid Function


Congenital Congenital hypoplastic thyroid gland

Acquired Partial or complete thyroidectomy for cancer or

thyrotoxicosis After radiation therapy for Hodgkin lymphoma or other

malignancy Rarely occurs from dietary insufficiency in United

States

Juvenile Hypothyroidism


Mental decline Constipation Sleepiness Myxedematous skin changes

Dry skin Sparse hair Puffiness around eyes

Clinical Manifestations of Juvenile Hypothyroidism


Oral thyroid hormone replacement Prompt treatment needed for brain growth in

infant May administer in increasing amounts over 4-8

weeks to avoid symptoms of hyperthyroidism Compliance with medication regimen: crucial

Therapeutic Management of Juvenile Hypothyroidism


Hypertrophy of the thyroid gland Congenital

Usually results from maternal ingestion of antithyroid drugs during pregnancy

Acquired Result of neoplasm, inflammatory disease, dietary

deficiency (but rarely in children), or increased secretion of pituitary thyrotropic hormone

Goiter


Goiters may become noticeable during periods of rapid growth

Large goiters may be obvious; smaller nodules may be evident only on palpation

Thyroid hormone replacement is necessary for treatment of hypothyroidism

Immediate surgery may be life-saving in infants born with goiter

Care Management of Goiter


Also known as “Hashimoto disease” or “autoimmune thyroiditis”

Most common cause of thyroid disease in children and teenagers

Accounts for largest percentage of juvenile hypothyroidism

Occurs most frequently after age 6 years, peaks during adolescence

Lymphocytic Thyroiditis


Enlarged thyroid gland Usually symmetric Firm, nontender Freely moveable

Tracheal compression Sense of fullness Hoarseness, dysphagia

Hyperthyroidism possible

Clinical Manifestations of Lymphocytic Thyroiditis


Goiter may be transient, asymptomatic Goiter may resolve spontaneously within 1-2

years Oral thyroid hormone administration often

decreases the goiter significantly Surgery is contraindicated in this disorder

Therapeutic Management of Lymphocytic Thyroiditis


Graves disease constitutes largest percentage of cases of childhood hyperthyroidism

It is believed to be caused by autoimmune response to TSH receptors

Signs include enlarged thyroid gland and exophthalmos

Incidence peaks between ages of 12 to 14 years, but condition may be present at birth

Familial association exists

Hyperthyroidism (Graves Disease)


Therapy: controversial Goal of therapy: to retard rate of hormone

secretion Treatments

Antithyroid drugs (propylthiouracil and methimazole) Subtotal thyroidectomy Ablation with radioiodine

Management of Graves’ Disease


Thyroid “crisis” or “storm” May occur from sudden release of hormone Unusual in children but can be life-threatening May be precipitated by infection, surgery, or

discontinuation of antithyroid therapy Treatment of thyroid storm

Antithyroid drugs Propranolol

Thyrotoxicosis


Identify children with hypothyroidism Be alert for signs and symptoms Child needs quiet environment, rest periods Help family cope with emotional lability Dietary requirements are higher to meet child’s

increased metabolic rate Medications have side effects

Care Management of Hypothyroidism


Parathyroid glands secrete parathormone (PTH) Function of PTH: to maintain serum calcium

level by Increasing release of calcium and phosphate from

bone demineralization Increasing absorption of calcium and excretion of

phosphate by the kidneys Promote calcium absorption in GI tract

Disorders of Parathyroid Function


May be caused by a specific defect in the synthesis of PTH

May also occur secondary to other conditions Infection and autoimmune syndromes Postoperatively after thyroidectomy Conditions during neonatal period

• Maternal hyperparathyroidism• Maternal diabetes mellitus• Formula with high phosphate-to-calcium ratio

Hypoparathyroidism


Dry, scaly skin with eruptions Brittle hair, thin nails with transverse grooves Tetany, paresthesias, tingling, laryngeal stridor,

spasms, or a combination of these Headache, seizures, emotional lability,

depression, confusion, memory loss

Clinical Manifestations of Hypoparathyroidism


Primary: adenoma of the gland Secondary: chronic renal disease, congenital

anomalies of urinary tract Common factor: hypercalcemia Rare in children

Hyperparathyroidism


Diagnostic evaluation Blood studies to identify increased calcium and

decreased phosphorus levels Therapeutic management: surgical removal or

treat underlying cause if possible Care management

Recognition of the disorder

Hyperparathyroidism (Cont.)


Adrenal cortex secretes three groups of “steroids” Glucocorticoids (cortisol, corticosterone) Mineralocorticoids (aldosterone) Sex steroids (androgens, estrogens, and progestins)

Altered levels of these produce significant dysfunction

Disorders of Adrenal Function


Adrenal medulla secretes catecholamines: epinephrine and norepinephrine

Catecholamine-secreting tumors are the primary cause of adrenal medullary hyperfunction

Disorders of Adrenal Function (Cont.)


Adrenal crisis Etiologic factors: hemorrhage into the gland from

trauma, fulminating infections, abrupt withdrawal of exogenous cortisone, failure to increase cortisone during times of stress

Diagnosis generally based on clinical symptoms

Acute Adrenocortical Insufficiency


Clinical symptoms Increased irritability, headache Abdominal pain, nausea, vomiting Hyperpyrexia, cyanosis, seizures

Diagnosis based on clinical presentation Therapeutic management

Acute Adrenocortical Insufficiency (Cont.)


Rare in children Causes:

Infections, neoplasms, autoimmune processes, or idiopathic

Symptoms: appear gradually after 90% of adrenal tissue is nonfunctional

Chronic Adrenocortical Insufficiency (Addison Disease)


Diagnosis Measurement of functional cortisol reserve

Therapeutic management Replacement of cortisol and aldosterone

Care management Parental guidance and education

Chronic Adrenocortical Insufficiency (Addison Disease) (Cont.)


A characteristic group of manifestations caused by excessive circulating free cortisol

May be caused by excessive or prolonged steroid therapy

Condition: reversible once steroids are discontinued

Abrupt withdrawal of steroids: may precipitate acute adrenal insufficiency

Cushing Syndrome


Excessive hair growth Moon facies, red cheeks Weight gain Pendulous abdomen with red striae Poor wound healing Ecchymosis

Cushingoid Appearance


Cushingoid Appearance (Cont.)


Measurement of serum cortisol levels Imaging of pituitary and treatment glands Skull films to examine the sella turcica Measurement of bone density Laboratory tests

Fasting blood glucose level Serum electrolyte levels 24-hour urine collection

Diagnostic Evaluation of Cushing Disease


Dependent upon the cause Surgical intervention Replacement of GH, ADH, thyroid hormone,

gonadotropins, and steroids Care management

Steroid administration early morning Alternate-day schedule Postoperative complications

Therapeutic Management of Cushing Disease


Occurs in 1 per 12,000-15,000 births Overproduction of adrenal androgens Results in virilization of the female fetus Varying degrees of ambiguous genitalia Salt-wasting crisis frequently occurs

Congenital Adrenal Hyperplasia


Administer glucocorticoids Diagnose and assign sex to the child according

to genotype Reconstructive surgery may be required Not all cases are diagnosed at birth These individuals are not fertile

Therapeutic Management of Congenital Adrenal Hyperplasia


Adrenal tumor that secretes catecholamines May occur around adrenal medulla, along

paraganglia of aorta, or along thoracolumbar sympathetic chain

Tumors often bilateral, multiple, benign Clinical manifestations: may mimic those of

other disorders

Pheochromocytoma


Surgical removal of tumor or tumors May require bilateral adrenalectomy and lifelong

glucocorticoid and mineralocorticoid therapy Care management

Identification of the condition Hypertension Behavioral changes

Therapeutic Management of Pheochromocytoma


Diabetes mellitus Characterized by a total or partial deficiency of the

hormone insulin The most common endocrine disorder of childhood Peak incidence between 10 and 15 years of age Increased risk for African American and Hispanic

children

Disorders of PancreaticHormone Secretion


Characterized by destruction of beta cells, usually leading to absolute insulin deficiency

Onset typically in childhood and adolescence but can occur at any age

Most childhood cases of diabetes mellitus are type 1

More prominent in white people

Type 1 Diabetes Mellitus


Arises because of insulin resistance Onset usually after age 45 Native American, Hispanic, and African

American children: at increased risk for type 2 diabetes mellitus

Affected people may require insulin injections

Type 2 Diabetes Mellitus


With a deficiency of insulin, glucose is unable to enter the cell and remains in blood, causing hyperglycemia

When serum glucose exceeds renal threshold, glucose spills into urine (glycosuria)

Cells break down protein for conversion to glucose by the liver (glucogenesis)

Pathophysiology of Diabetes Mellitus


When glucose is unavailable for cellular metabolism, the body breaks down alternative sources of energy; ketones are released, and excess ketones are eliminated in urine (ketonuria) or by the lungs (acetone breath)

Ketones in the blood are strong acids that lower serum pH and produce ketoacidosis

Ketoacidosis


Pediatric emergency Results from progressive deterioration with

dehydration, electrolyte imbalance, acidosis, coma; may cause death

Therapy: should be instituted in an intensive care unit setting

Diabetic Ketoacidosis


Microvascular complications, especially nephropathy and retinopathy

Macrovascular disease, neuropathy With poor control, vascular changes as early as

2.5-3 years after diagnosis With excellent control, can be delayed 20 years

Long-Term Complications of Diabetes Mellitus


Multidisciplinary approach Insulin therapy Glucose monitoring; goal, near normal levels of <126

mg/dL Laboratory measurement of hemoglobin A1c; goal,

≤7% Glycerin control: decreases risk of long-term

complications Selection of appropriate insulin preparation

Therapeutic Management of Type 1 Diabetes Mellitus


Therapeutic Management of Type 1 Diabetes Mellitus (Cont.)


Nutrition Exercise Morning measurement for hyperglycemia Illness management Management of diabetic ketoacidosis Fluid and electrolyte therapy

Therapeutic Management of Type 1 Diabetes Mellitus (Cont.)


Nature of the disease Meal planning Traveling Insulin therapy

Injection procedure Continued subcutaneous insulin infusion

Glucose monitoring

Patient Education: Diabetes Mellitus and Insulin Therapy


Patient Education: Diabetes Mellitus and Insulin Therapy (Cont.)


Recognition and treatment of hypoglycemia and hyperglycemia

Management of “minor” illnesses Record keeping Exercise Hygiene Self-management Family support



A nasal spray of desmopressin acetate (DDAVP) is used to treat

A. HypopituitarismB. Diabetes insipidusC. Acute adrenocortical insufficiencyD. SIADH

Question


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