Transcript CLinical Manifestations

Chapter 7
The endocrine system
The endocrine system, along with the nervous
system, allows for communication between
distant sites in the body.
the endocrine system has three components :
1-endocrine glands that secrete chemical
messengers into the bloodstream;
2-the chemical messengers themselves, called
hormones;
3-and the target cells or organs that respond to
the hormones.
Conditions of Disease or Injury
Hypothyroidism
Result from malfunction of the thyroid gland, the pituitary,
or the hypothalamus.
-If it results from thyroid gland malfunction, low TH (thyroxin
hormone) levels are accompanied by high TSH( thyroid
stimulating hormone) and high TRH (thyroid releasing
hormone) because of the lack of negative feedback on the
pituitary and hypothalamus by TH.
-If hypothyroidism results from pituitary malfunction, low
levels of TH are caused by low TSH. TRH from the
hypothalamus is high because there is no negative
feedback on its release by TSH or TH.
-
- Hypothyroidism caused by hypothalamic
malfunction results in low TH, low TSH, and low
TRH.
Causes of Hypothyroidism
• - Hashimoto's disease, also called autoimmune
thyroiditis, results from autoantibody destruction of
thyroid gland tissue.
• - Endemic goiter is hypothyroidism caused by a
dietary deficiency of iodide. A goiter is an
enlargement of the thyroid gland.
• - Thyroid carcinoma may cause hypothyroidism or
hyperthyroidism.
Clinical Manifestations
• - Sluggishness and slow thinking, and slow
movements.
• - Decreased heart rate.
• - Edema of the skin, especially under the eyes and in
the ankles(myxedema)
• - Intolerance to cold temperatures.
• - Decreased metabolic rate, decreased caloric
requirements, decreased appetite and nutrient
absorption across the gut.
• - Constipation
Diagnostic Tools
Measuring levels of TH (both T3 and T4), TSH, and TRH
will allow diagnosis of the condition and localization
of the problem .
Hyperthyroidism
Hyperthyroidism is excessive levels of circulating TH.
-Increased TH caused by malfunction of the thyroid
gland is accompanied by decreased TSH and TRF, as
a result of the negative feedback on their release by
TH.
-Hyperthyroidism caused by malfunction of the
pituitary results in high TH and high TSH. TRF is low
because of negative feedback from TH and TSH.
-Hyperthyroidism caused by malfunction of the
hypothalamus shows high TH accompanied by
excess TSH and TRH.
Clinical Manifestations
• - Increased heart rate.
• - Increased muscle tone, tremors, irritability
• - Increased basal metabolic rate and heat production,
intolerance to heat, excess sweating.
• - Weight loss, increased hunger.
• - Exophthalmos (bulging of the eyes) may develop.
• - Increased number of bowel movements.
• - Goiter (usually), which is an increase in the size of the
thyroid gland.
Diagnostic tools
- Measuring levels of TH (both T3 and T4), TSH, and TRH will
allow diagnosis of the condition and localization of the
problem.
Adrenal Insufficiency
Adrenal insufficiency is a decrease in the
circulating level of the glucocorticoids.
The mineralocorticoid aldosterone may
also be reduced.
Adrenal insufficiency may be caused by
dysfunction of the adrenal gland, called
primary adrenal insufficiency, or by
dysfunction of the pituitary or
hypothalamus. Both of these latter
conditions cause secondary adrenal
insufficiency.
•Primary adrenal insufficiency is characterized by
low levels of glucocorticoids, especially cortisol,
accompanied by high ACTH( adreno corticotropic
hormone) and high CRH( cortzone releasing
hormone) because there is no negative feedback on
their release.
•If the cause of adrenal insufficiency is secondary to
a pituitary dysfunction, low glucocorticoids will be
accompanied by low ACTH and high CRH. In this
case, adrenal androgens will also be low.
•If there is zero ACTH, aldosterone levels will be
reduced. If adrenal insufficiency is caused by a
hypothalamus malfunction, the glucocorticoids,
ACTH, and CRH will be low.
Diseases of Adrenal Insufficiency
• Primary adrenal insufficiency, called Addison's disease,
occurs from destruction of the adrenal cortex. The
disease is usually autoimmune, and may results from
infections such as TB or tumors.
Addison's disease is characterized by low glucocorticoid
levels accompanied by high ACTH and high CRH. Total
loss of the adrenal gland results in the loss of adrenal
androgens and aldosterone as well. Aldosterone
deficiency leads to increased loss of sodium in the
urine, resulting in hyponatremia (decreased sodium in
the blood), dehydration, and hypotension (because
water loss in the urine frequently accompanies the loss
of sodium). Decreased potassium excretion in the urine
will lead to hyperkalemia (increased potassium
concentration in the blood).
Clinical Manifestations
• - Depression, because cortisol levels influence mood
and emotions.
• - Fatigue, related to hypoglycemia, and decreased
gluconeogenesis.
• - Anorexia, vomiting, diarrhea, and nausea.
• - Hyperpigmentation of the skin if ACTH levels are high
(primary adrenal insufficiency) as a result of ACTH
having melanin-stimulating hormone like effects on the
skin.
• - Sparse body hair in women, if the adrenal cells
producing androgens are destroyed .
• - Inability to respond to stressful situations, perhaps
leading to severe hypotension.
Glucocorticoid Excess
Glucocorticoid excess refers to any condition in
which there are very high levels of circulating
glucocorticoids. The cause of glucocorticoid excess
may reside at the level of the adrenal gland or at
the pituitary/hypothalamic level. If the cause of
glucocorticoid excess is primary adrenal gland
hypersecretion, there is usually an adrenal tumor
present. In this situation, low ACTH and low CRH
levels will be present as a result of negative
feedback from high glucocorticoids. Adrenal
androgen levels will be low because ACTH is low.
Bronzing of the skin will not occur.
Diseases of Excess Glucocorticoids
• - Cushing's syndrome refers to any condition of high
glucocorticoids and includes glucocorticoid excess
caused by therapeutic administration of
corticosteroids.
• - Cushing's disease refers to high glucocorticoids
caused specifically by malfunction of the anterior
pituitary resulting in excess ACTH.
Clinical Manifestations
• - Altered fat metabolism leading to fat pads on the
back (buffalo hump), moon face, protruding
abdomen with thin extremities, and stretch marks
on breasts, thighs, and abdominal surface.
• - Muscle weakness from protein breakdown.
• - Hypertension as a result of increased
catecholamine responsiveness.
• - Weight gain resulting from strong appetite
stimulation.
• - Inhibition of immune and inflammatory reactions,
leading to poor wound healing.
• - Masculinization of women and children as a result
of adrenal androgen stimulation if ACTH levels are
high.
• - Bronzing of the skin if ACTH levels are high.
Growth Hormone Deficiency(Dwarfism)
• Growth hormone deficiency is a decrease in circulating
levels of GH. Most cells of the body will be affected. GH
deficiency is usually clinically recognized only in
children. Usually is caused by a pituitary adenoma .
• Clinical Manifestations
• - proportional short stature .
• - Delayed onset of puberty
Growth Hormone Excess
• Growth hormone excess is the increase in circulating
levels of GH usually caused by a GH-secreting tumor of
the anterior pituitary.
Diseases of GH Excess
• - Gigantism, a disease of excess longitudinal growth of
the bones of the skeleton, is seen as a result of GH
excess before puberty.
• - Acromegaly, a disease of connective tissue
proliferation, is seen in adults with GH excess. Because
long bone growth has stopped in adults, GH excess
cannot cause growth of the skeleton. It is associated
with growth of the cartilage of the hands, feet, nose,
jaw, chin, and facial bones.
Clinical Manifestations
• - Tall stature with gigantism.
• - Thickening of the fingers, jaw, forehead, hands, and
feet with acromegaly.
Gonadotropin Deficiency
Gonadotropin deficiency is a decrease in circulating
levels of FSH and LH.
Clinical Manifestations
• - Amenorrhea (lack of menstrual periods), vaginal,
uterine, and breast atrophy in women.
• - Testicular atrophy and reduction in beard growth
in men.
Syndrome of Inappropriate Antidiuretic Hormone
(ADH)
(SIADH) is characterized by increased release of ADH from
the posterior pituitary
Clinical Manifestations
• - Water retention and weight gain.
• - Decreased urinary output.
• - Nausea and vomiting worsening with the degree of
water intoxication.
Diagnostic Tools
Blood tests measuring increased levels of ADH with low
plasma sodium concentration ( hyponatremia) .
Diabetes Insipidus
Diabetes insipidus is a disease of decreased ADH
production.
Clinical Manifestations
- Large volumes of dilute urine.
- Polydipsia (excessive thirst).
Diagnostic Tools
Blood tests measuring decreased levels of ADH with
hypernatremia will allow diagnosis of the condition.
Complications
Severe dehydration may occur if large volumes of
drinking water are unavailable.
Chapter 8
The Musculoskeletal System
Muscular Dystrophy
It refers to a variety of diseases characterized by
wasting of the muscles. Muscle cells die and are
phagocytized by cells of the inflammatory system,
leading to scaring and loss of muscle function.
The most common form of muscular dystrophy is
Duchenne's muscular dystrophy, a sex-linked
disorder passed on the X chromosome and seen
almost exclusively in males. In approximately 50%
of cases, the disease shows a clear family history
and is passed from mother to son.
Clinical Manifestations of Duchenne's Muscular
Dystrophy
- Waddling gait, and frequent falls in toddlers.
- Walking on toes because of anterior tibial
weakness.
- Decreased deep tendon reflexes.
- Pseudohypertrophy of the calf muscles.
- Gowers' maneuver, whereby the child uses his arms
to push up onto his legs when standing up from the
floor, is seen during the toddler years.
- Immobility and confinement to a
wheelchair by the early teens.
- Curvature of the spine
(kyphoscoliosis) caused by weakness
of the postural muscles.
- Frequent respiratory infections from
failure to fully expand the lungs.
Diagnostic Tools
- Serum levels of the muscle enzyme
creatinine phosphokinase (CPK) are
elevated.
- Muscle biopsy will demonstrate cell
death, scar tissue, and fatty infiltration.
- Electromyography recordings
(measurements of electrical signals in a
muscle) will be reduced.
Acute Osteomyelitis
Osteomyelitis is an acute infection of the
bone that may occur in two froms:
1-Hematogenous osteomyelitis :bloodborne infection
2-Exogenous osteomyelitis after
contamination of an open fracture or
surgical reduction.
Clinical Manifestations
-In children may include fever, chills, and a
reluctance to move a particular limb.
-In adults, symptoms may be vague and include
fever, fatigue, and malaise.
-A urinary, respiratory tract, ear, or skin
infection frequently precedes hematogenous
osteomyelitis.
-Exogenous osteomyelitis typically presents
with evidence of injury and inflammation at
the site of pain. Fever and regional lymph node
enlargement occur.
Osteoporosis
Is a metabolic bone disease characterized by a
severe reduction in bone density, leading to easy
bone fracture. Osteoporosis occurs when the rate of
bone resorption greatly exceeds the rate of bone
formation.
Causes of Osteoporosis
The rate of bone formation decreases progressively
with age, beginning at approximately age 30 or 40.
The denser the bones are before that time, the less
likely osteoporosis will occur. As people age into
their 70s and 80s, osteoporosis becomes a common
disease.
Osteomalacia and Rickets
Osteomalacia is a metabolic bone disease
seen in adults. It is caused by decreased
mineralization of the osteoid as a result of a
deficiency of calcium, phosphate, or from a
vitamin D deficiency or from renal disease.
Rickets is a bone disease in children caused by
vitamin D deficiency.
Clinical Manifestations
- Osteomalacia may be symptomless until a
fracture occurs. Vertebral collapse is common, with
associated changes in posture and height.
- Rickets is characterized by permanent skeletal
deformity, including bowed legs, lumbar lordosis, and
rib and skull deformity. Inability to to walk without
support and may also show poor dentition.
Diagnostic Tools
- Radiograph evaluation can demonstrate reduced
bone ossification.
- Measurements of serum calcium and phosphate
will be low in severe cases.
Osteoarthritis
Is a degenerative bone disease characterized by loss of
articular (joint) cartilage. Without cartilage buffering,
the underlying bone is irritated, leading to
degeneration of the joint.
CLinical Manifestations
- Pain and stiffness in one or more of the joints,
commonly the hands, wrists, feet, knees, upper and
lower spine, hips, and shoulders. Pain may be
associated with tingling or numbness, especially at
night.
- Swelling of the affected joints, with a decreased range
of motion. Joints may appear deformed.
Rheumatoid Arthritis
(RA) is a chronic, inflammatory disease that causes
degeneration of connective tissue ,first is the synovial
membrane and spreads to the surrounding structures
of the joint, including the articular cartilage and the
fibrous joint capsule. Eventually, the ligaments and
tendons become inflamed.
Clinical Manifestations
- Onset of RA is characterized by general symptoms of
inflammation, including fever, fatigue, body aches, and
joint swelling. Joint tenderness and stiffness develop.
- Decreased range of motion, joint deformity and
muscular contractions.
Talipes Equinovarus
Talipes equinovarus, also called
clubfoot, is a congenital abnormality
characterized by deformity of the
bones and soft tissue of the foot.
The front portion of the foot is
turned in whereas the rear of the
foot is inverted.