Final Flashcards

(250 cards)

1
Q

What would be the end result of the disease processes involving the peripheral nerves, neuromuscular function, & skeletal muscle?

A

Disease involving these structures result in muscular weakness

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2
Q

What’s the difference b/w disease process only involving muscle & disease process only involving peripheral nerves?

A

Disease process only involving muscle will result in motor dysfunction alone, whereas the peripheral nerves also have sensory & autonomic fibers

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3
Q

What does the term “nerve” really mean?

A

Collection of several integrated neurons

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4
Q

How do peripheral nerves receive their blood supply?

A

By small arterioles called the vasa nervorum

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5
Q

What is meant by the term “laminae”?

A

When the cell bodies of neurons tend to aggregate into sheets it’s called laminae. Lie w/i the gray matter of the CNS or are located in specialized ganglia in the PNS

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6
Q

How many glial cells are there in the body compared w/ neurons?

A

There are about 10x more glial cells than neurons & they occupy approx. half the volume of the brain

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7
Q

What is the cell body of a neuron AKA?

A

soma or perikaaryon

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8
Q

What is the nissl substance AKA?

A

endoplasmic reticulum

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9
Q

What is the function of endoplasmic reticulum?

A

Synthesizes proteins for export to the axon

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10
Q

What is the name of microtubule-assoc. protein in axons?

A

Tau protein

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11
Q

What is the name of microtubule-assoc. protein in dendrites?

A

MAP-2

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12
Q

What does a synapse consist of?

A

A presynaptic element containing synaptic vesicles
A synaptic cleft
A postsynaptic element

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13
Q

How wide is the synaptic cleft b/w neurons?

A

20-30nm wide

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14
Q

How wide is the synaptic cleft b/w neurons & skeletal neuromuscular junction?

A

50-100nm wide

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15
Q

What types of neuroglial or glial cells are in the CNS?

A

Astrocytes
Oligodendrocytes
Microglia

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16
Q

These cells for a framework or scaffolding for neurons (especially in the formation fo the blood-brain-barrier) & some expand into end-feet on the pial surfaces of the brain or on capillaries

A

Asrtocytes

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17
Q

These cells have fewer & thinner processes than astrocytes, they don’t possess gap junctions, & they form myelin sheaths around axons in the CNS

A

Oligodendrocytes

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18
Q

Type of cell of uncertain origin that act as as scavenger cells. Injury to the brain activates these cells which undergo proliferation & migrate to the point of injury where they become phagocytic & remove debris

A

Microglia

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19
Q

What types of neuroglial or glial cells are in the PNS?

A

Schwann cells

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20
Q

What is the function of Schwann cells?

A

Fill spaces between neurons & they form myelin sheaths around axons in peripheral nerves by enveloping them w/ concentric layers of plasma membranes

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21
Q

Are ependymal cells classified as glial cells?

A

Yes. Ependymal cells which line the ventricles of the brain may also be classified as glial cells

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22
Q

What factors makes the nervous system more susceptible to toxins?

A

Neurons have a very limited ability to regenerate
Nerve cells have a large surface area
The nervous system depends for its normal activity on a high degree of integrated activity

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23
Q

This consists of tightly-packed endothelial cells wrapped by astrocytes that line the capillaries in the brain

A

Blood brain barrier

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24
Q

What is the effect of the blood brain barrier on the CNS?

A

Reduces, doesn’t eliminate, the entry of toxins into the CNS

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25
What type of molecules may still penetrate the blood brain barrier?
Low molecular weight, lipid-soluble, nonpolar molecules
26
In what regions of the CNS is the blood brain barrier less well-established?
Pituitary gland, the hypothalamus, & the peripheral nervous system
27
Which type of medications are likely to have a great deal of trouble trying to pass through the blood brain barrier?
Molecules that are polar or of high molecular weight
28
Which part of the axon is likely to be affected by toxins?
Part of the axon near the neuron body The proximal axon The distal axon
29
Why is the axon less likely to suffer the effects of toxins than the cell body?
because it has very limited metabolic functions
30
Where in the nervous system is pathological injury to the axons likely to occur?
M/C in the peripheral nervous system & the resulting neurological damage is called a neuropathy
31
Which portion of the axon is M/C involved in axonopathies?
The distal axon
32
Evidence of axonopathies includes what?
Swelling Damage to mitochondria Accumulation of neurofilaments Disintegration of myelin
33
How do peripheral nerves react to injury?
Injury to the perikaryon leads to irreversible degeneration of both mylinated & nonmyleinated axons. Transection of the axon can be repaired as long as the cell body is viable
34
What are the 3 types of myelinated nerve injuries?
Distal axonal degeneration Wallerian degeneration Segmental demyelination
35
What is distal axonal generation?
Injury of the perikaryon that leads to "dying back" injury of the axon, which starts most distally & spreads proximally toward the perinuclear portion of the cytoplasm
36
Degeneration of the axon in distal axonal degeneration is accompanied by what?
Breakdown of the myelin enveloping the damaged axon (Secondary demyelination)
37
In what type of neuropathies is distal axonal degeneration seen in?
Toxic & drug-related neuropathies (isoniazid neuropathy & Vit. B1 deficiency)
38
What is Wallerian degeneration?
Typically occurs in transected axon. Distal to the site if transection, the axon degenerates together w/ its myelin sheath. Proximally, the axon dies back to the next node of Ranvier, but the stump can regenerate & the new axon is formed & myelinated by the adjacent Schwann cell
39
What is segmental demyelination?
Axonal injury is secondary & it follows an injury of Schwann cells, leading to a loss of myelin sheath (primary demyelination)
40
Segmental demyelination typically occurs b/c what?
Ischemia d/t immune injury of myelin sheaths or toxic neuropathies
41
This type of neuropathy involves injury of myelin sheaths, which is sometimes accompanied by concentric regeneration of Schwann cells in the form of hypertrophic "onion bulbs"
Hereditary neuropathies
42
How are neuropathies classified clinically?
According to duration (Acute vs. Chronic) or by distribution of lesions
43
This form of disease presents w/ symptoms pertaining to a single nerve, such as radial or ulnar nerve in carpal syndrome
Mononeuropathy
44
This form of disease presents w/ symptoms pertaining to several isolated nerves usually affected in an unpredictable manner as in polyarteritis nodosa
Mononeuritis multiplex
45
This form of disease is when numerous, & sometimes all, nerves are involved, as in various toxic neuropathies, Alcoholic neuropathy, Guillain-Barre syndrome, & carcinomatous neuropathy
Polyneuropathy
46
What does carcinomatous mean?
Manifesting the characteristic properties of carcinoma
47
How does polyneuropathy present clinically?
Predominately motor neuropathy (e.g. Guillian-Barre syndrome) Predominately sensory neuropathy (e.g. carcinomatous neuropathy) Combined sensory-motor (e.g. alcoholic or diabetic neuropathy)
48
What is the M/C form of neuropathy?
Combined sensory-motor
49
Peripheral neuropathy is most often which type of neuropathy?
sensory-motor type
50
This is an uncommon disease that follows a viral infection in a majority of cases, M/C Herpes virus, Epstein-Barr virus, & CMV infections. Less frequently, it's precipitated by injection of foreign proteins, immunization, or trauma
Guillain-Barre Syndrome
51
Guillain-Barre syndrome is AKA?
Inflammatory Demyelinating Disease or IDN
52
Guillain-Barre syndrome was assoc w/ what vaccination program?
Swine flu vaccine of 1976-77
53
Guillain-Barre Syndrome starts where in the body?
Starts in the feet & goes up
54
What are pathological features of Guillain-Barre syndrome?
Can affect any part of the PNS Affecte nerves are infiltrated w/ lymphocytes & macrophages Demyelination is prominent but the axons are spared
55
"Onion bulbs" seen in Guillain-Barre are a result of what?
Recurrent demyelination & remyelination & are seen in chronic stages of the disease
56
What change is seen in the CSF in Guillian-Barre?
Typical change called cell-protein dissociation; the cell count is normal but the protein is markedly elevated
57
How does Guillain-Barre usually present clinically?
Usually presents w/ an acute onset of motor symptoms such as muscle weakness or paralysis mainly in lower extremities (flaccid parapareis w/ urinary incontinence)
58
What does paraparesis mean?
A slight degree of paralysis, affecting the lower extremities
59
In severe case of Guillain-Barre, what part of the body can be involved?
Upper extremities & respiratory muscles
60
What is the time frame for progression of Guillain-Barre?
Paralysis progresses for 1-4 weeks & then slowly improves over several months b/c of a very slow rate of regeneration of axons w/i the restored myelin sheaths (90% of pts recover completely)
61
What is the treatment for Guillain-Barre?
Treatment is supportive. | In severe cases or in the presence of respiratory compromise, plasmapheresis may be beneficial
62
What is the M/C peripheral neuropathy encountered in clinical practice?
Diabetic neuropathy
63
What causes diabetic neuropathy?
Neuropathy (& cataract as well) in diabetic pts are believed to result from accumulation of sorbitol w/i nerve (or lens) tissue
64
What enzyme produces sorbitol in tissues when glucose levels are high
Aldose Reductase
65
What are nerves, lens, small vessels, & kidney particularly vulnerable to accumulation of sorbitol?
Glucose can enter these cells even in low-insulin states
66
This is characterized by diffuse thickening of the basement membranes of capillaries throughout the body
Diabetic microangiopathy
67
What areas are commonly involved w/ diabetic microangiopathy?
Kidney, retina, skin, & skeletal muscles
68
What is abnormal about the thick basement membrane in diabetics?
Increased amount of collagen & laminin & decreased proteoglycans. Thick basement membrane leads to increased permeability to fluid & protein macromolecules
69
What is the suggest mechanism that causes diabetic microangiopathy?
Prolonged elevation of serum glucose increases glycosylation of basement membrane proteins in a manner similar to glycosylation of hemoglobin
70
What is the M/C infectious neuropathy in the USA?
HIV infections & AIDS are often accompanied by polyneuropathy which may be related directly to HIV infection or complication of the body's immune response or toxicity of the drugs used in treatment
71
What is the M/C form of AIDS peripheral neuropathy?
Chronic axonal polyneuropathy
72
What are the different forms of neuropathy seen in HIV/AIDS pts?
Chronic axonal polyneuropathy Inflammatory Demyelinating Neuropathy (Guillain-Barre) Infectious Polyneuropathy (CMV or herpes zoster) Toxic Neuropathy (related to drugs for HIV treatment)
73
Nerve biopsy is indicated in cases where what types of pathologies are suspected?
Vasculitis Amyloidosis Granuloma Inflammation
74
How does amyloid affect peripheral nerves?
Deposits of amyloid may be found in the wall of small blood vessels providing blood to the peripheral nerves or in the extracellular matrix of the endoneurium surround the axon. These deposits may cause axonal & myelin sheath injuries
75
Deposits of amyloid in ganglia are typically assoc. w/ what type of symptoms?
Autonomic
76
What is the M/C form of chronic peripheral neuropathy in children?
Charcot-Marie-Tooth disease
77
How does Charcot-Marie-Tooth disease present pathologically?
Characterized by demyelination & axonal degeneration w/ subsequent remylination that leads to the formation of "onion bulbs" & remarkable thickening of peripheral nerves
78
How does Charcot-Marie-Tooth disease present clincally?
Relatively common hereditary disorder. Characterized by weakness & atrophy in distal leg muscles. Pts present in middle childhoow w/ foot drop, & slowly progressive distal muscle atrophy producing "stork leg deformity". Intrinsic muscle wasting in the hand begins later.
79
What do biopsies show in children w/ Charcot-Marie-Tooth disease?
Wallerian degeneration
80
This syndrome resembles Charcot-Marie-Tooth disease but is much more severe w/ onset in early infance
Dejerine-Sottas syndrome
81
How do peripheral nerves appear in pts w/ Dejerine-Sottas syndrome?
Show a severe demyelinating neuropathy w/ "onion bulbs" & axonal loss
82
What are the most important peripheral nerve tumors?
Neurofibroma Schwannoma (neurilemmoma) Malignant peripheral nerve-sheath tumor
83
What are the typical symptoms & signs of muscle disease?
``` Weakness or paralysis Atrophy Hypertrophy or pseudo-hypertrophy Irregular contractions, spasms, or fasciculations Pain & tenderness to palpation ```
84
What is hypertrophy or pseudo-hypertrophy of muscles typically caused by?
Infiltration of muscles by fat cells
85
What are the different classifications of muscle diseases?
``` Genetic Endocrine Neurogenic Ethanol (Alcohol) Toxic Inflammatory Crush injury (trauma) ```
86
What are the three morphologic patterns assoc w/ muscle diseases?
Myopathic pattern Neuropathic pattern Normal muscle histology
87
In this morphologic muscle pattern the muscle fibers show signs of injury or necrosis usually assoc. w/ an inflammatory response & repair in the form of fibrosis & limited attempts at regeneration. These findings indicate that the primary site of injury is the muscle itself
Myopathic Pattern
88
In this morphologic muscle pattern, the muscle fibers show signs of atrophy caused by denervation. Muscle changes are obviously secondary to a nerve injury or diseases of the nervous system
Neuropathic Pattern
89
In this morphologic muscle pattern the signs of muscle weakness are not assoc. w/ any microscopically visible changes in the muscle biopsy (think Myastenia Gravis)
Normal Muscle Histology
90
What are the two main categories that muscle diseases are classified clinically & pathologically?
Neurogenic Disorders | Myopathies
91
What is the cause of a neurogenic disorder?
Results from damage to the muscle innervation
92
This type of neurogenic disorder is a progressive degenerative disorder affecting prinicipally the ant. horn neurons in the spinal cord which results in denervation atrophy, fasciculation, & weakness in affected muscles
Motor Neuron Disease
93
If a muscle cell nuclei is located _______ it indicates there is a pathology
Centrally
94
Type of neurogenic disorder that is a group of inherited degenerative diseases affecting CNS motor neurons. The gene for this group of diseases lies on the long arm of chromosome 5
Spinal Muscular Atrophy
95
What are the characteristics of Type 1 spinal muscular atrophy disease (Werding-Hoffmann disease)?
Onset before 3 months of age & is sometimes present at birth Rapidly progressive Results in death before the age of 18 months
96
What are the characteristics of Type 2 spinal muscular atrophy disease?
Affects infants & children; onset b/w 6-12 months of age More slowly progressive than Type I Causes severe disability Variable life expectancy
97
What are the characteristics of Type 3 spinal muscular atrophy disease (Kugelberg-Welander disease)?
Onset b/w 2-15 yrs of age Slowly progressive Mild to moderate disability Usually allows survival into adult life
98
What are the characteristics of Type 4 spinal muscular atrophy disease?
Affects adults Very slow course Often causing mild disability Its progress may become arrested after several decades
99
This type of neurogenic disorder involves motor nerves often present clinically w/ muscle wasting & weakness accompanied by sensory loss in a "glove & stocking" distribution
Peripheral neuropathy
100
What are examples of misc spinal cord disorders?
Poliomyelitis Syringomyelia (AKA Morvan's disease or hydrosyringomyelia) Degenerative diseases of the vertebral column
101
This spinal cord disorder is seen in the longitudinal cavities lined by dense, gliogenous tissue & not caused by vascular insufficiency; it's marked clinically by pain & parethesia followed by muscular atrophy of the hands
Syringomyelia AKA Morvan's disease AKA Hydrosyringomyelia
102
These types of myopathies from a hroup of inherited disorders, results in the progressive destruction of muscle fibers, and in most cases the muscle innervation is normal
Muscular dystrophies
103
A muscular dystrophy that is a x-linked disorder affecting 1 in 3,000-5,000 live male births where appox. 1/3rd of cases represent new mutations where the affected gene product is dystrophin
Duchenne dystrophy
104
Where is the affected gene for Duchenne located?
p21 region of the X chromosome
105
What features are seen in a biopsy of Duchenne?
Abnormal variation in the diameter of the muscle fibers w/ many fibers showing hyaline degeneration or necrosis, w/ attempts at regeneration. Partial or complete absence of dystrophin
106
What happens in Duchenne as the muscle fiber progresses?
Muscle is almost totally replaced by fat & connective tissue
107
What do gene deletions in Duchenne dystrophy result in?
A deficiency of dystrophin in muscle fiber membranes causing muscle fiber damage by disruption of the cell membrane, leading to uncontrolled entry of calcium into the cell
108
When & how does Duchenne initially present?
Usually presents b/w 2 & 4 yrs of age w/ prox. muscle weakness (pelvic girdle) & pseudohypertrophy of the calves
109
What enzyme is elevated in the early stages of Duchenne?
serum creatine phosphokinase (CPK)
110
What is the M/C of death in pts w/ Duchenne?
Cardiomyopathy before age of 20
111
Medical sign assoc. w/ Duchenne that describes a pt that has to use his or hands & arms to "walk" up his or her own body from a squatting position due to lack of hip & thigh muscle strength
Gower's sign
112
This is a muscular dystrophy that is a X-linked disorder that exhibits many similarities to Duchenne dystrophy, but the onset occurs at a later age w/ a slower progression of the disease
Becker dystrophy
113
In what way is Becker dystrophy similar to Duchenne?
It involves deletions in the p21 region on the X chromosome
114
What makes Becker's different from Duchenne's?
In Becker's, dystrophin is abnormal but not absent
115
Pts w/ Becker's are usually what gender & age?
Middle-aged men
116
This type of muscular dystrophy is inherited as autosomal recessive w/ an onset that can occur in childhood or adult life, usually w/ weakness in the pelvic girdle & then later in the shoulder girdle
Limb girdle dystrophy
117
What does a muscle biopsy show in a pt w/ lib girdle dystrophy?
Shows typical dystrophic featuers of fiber destruction & regeneration, but to a lesser degree than occurs in Duchenne
118
This muscular dystrophy is an autosomal dominant disorder w/ the genetic locus for which is chromosome 4q35
Facioscapulohumeral dystrophy
119
How does Facioscapulohumeral dystrophy usually present?
Usually presents in children & young adults w/ weakness of the face & shoulder girdle
120
What does a muscle biopsy show in a pt w/ Facioscapulohumeral dystrophy?
Shows features of a slowly progressive dystrophy, in which local lymphocytic infiltration is occasionally present
121
This muscular dystrophy is an autosomal dominant condition, the gene for which has been localized to chromosome 19
Myotonic dystrophy
122
What does myotonia mean?
Persistence of contraction after voluntary effort has ceased
123
What is the genetic abnormality in myotonic dystrophy?
An unstable CTG repeat sequence in a cAMP-dependent protein kinase
124
How does myotonic dystrophy usually present?
Presents b/w 20-30 yrs of age w/ weakness & wasting of facial limb girdle & prox. limb muscles
125
What systemic disorders do pts usually exhibit w/ Myotonic dystrophy?
Cataracts Balding (wouldn't call it a "disorder") Gonadal atrophy Diabetes mellitus
126
What does muscle biopsy show in a pt w/ Myotonic dystrophy?
Dystrophic changes, in which many fibers contain internal nuclei & exhibit a variety of cytoskeletal abnormalities
127
Examples of infecting organisms that can cause inflammatory myopathies
Bacteria (Group A strep, clostridia) Viruses (Coxsackie B, Influenza) Parasites (Toxoplasma, Trichinella, Tenia solium)
128
Examples of systemic inflammatory disorders that cause inflammatory myopathies
Sarcoidosis SLE Polyarteritis nodosa
129
What is the M/C inflammatory myopathy, occurring most frequently in adults?
Polymyositis
130
Who does polymyositis affect more, males or females?
Females
131
What differentiates polymyositis from dermatomyositis?
In dermatomyositis, the muscle inflammation is accompanied by skin involvement, in the form of a characteristic violaceous facial rash, particularly in children
132
In polymyositis/dermatomysitis the muscle fiber damage results from what?
Immunological injury by cytotoxic T-lymphocytes & macrophages
133
What organism has been implicated in some cases of polymyositis/dermatomyositis?
Coxsackie virus
134
This type of inflammatory myopathy shows up most frequently in elderly pts & clinically resembles polymyositis. Has an unknow etiology but affected muscles show inflammation & fiber necrosis, assoc. w/ small filamentous intracellular inclusions & vacuoles
Inclusion body myositis
135
What differentiates inclusion body myositis from polymyositis?
Unlike polymyositis, it responds poorly to corticosteroids & azathioprine
136
This type of inflammatory myopathy in most cases presents w/ hypotonia & floppiness in infancy which may prove fatal in severe cases
Congential myopathies
137
What does diagnosis of congenital myopathies depend largely upon?
Muscle biopsy appearances which are thought to reflect delayed development & maturation of the muscle fibers
138
What is a common manifestation of muscle disease in infancy but may be d/t other disorders such as cerebral palsy, hypothyroidism, & down's syndrome?
Hypotonia
139
Type of metabolic myopathy that is an uncommon, dominantely inherited disorder that results in an abnormal sensitivity in certain anesthetic agents such as halthane, which can result in fatal hyperpyrexia on exposure
Malignant hyperthermia
140
What are examples of endocrine myopathies?
Hypothyroidism Hyperthyroidism Cushing's syndrome
141
What are examples of substances that can cause toxic myopathies?
Corticosteroids Penicillamine Ethanol (one of the M/C)
142
This type of toxic myopathy is induced by bouts of heavy drinking, which can cause acute fiber necrosis; release of myoglobin from the damaged fibers may result in acute renal failure
Acute alcoholic myopathy
143
This type of toxic myopathy occurs in chronic alcoholics & presents w/ prox. muscle weakness & wasting; reversible in early stages
Subacute alcoholic myopathy
144
This is an acquired autoimmune disease characterized by abnormal muscular weakness, caused by circulating autoantibodies to the Ach receptor at the myoneural junction
Myasthenia Gravis
145
How does neonatal myasthenia in the newborn occur?
Ach receptor antibody is an IgG antibody so it may cross the placenta in pregnancy
146
This organ is involved w/ the etiology of myasthenia gravis but is not the source of the autoantibody
Thymus
147
Up to 40% of pts w/ myasthenia gravis have what type of tumor which is often cured by surgical removal?
Thymoma
148
Who does myasthenia gravis affect?
all races, 2:1 women to men, 20-30 yrs of age (females) & 50-60 yrs of age (males)
149
Muscle weakness in myasthenia gravis is typically aggravated by what?
Repeated contractions
150
What muscles are affected first in pts w/ myasthenia gravis?
Muscles w/ the smallest motor units, most typically the ocular muscles (bilateral ptosis)
151
How long does it take myasthenia gravis to progress to respiratory muscle involvement?
5 to 20 yrs after onset
152
If untreated, what % of pts w/ myasthenia gravis die w/i 10 yrs?
40%
153
What are the 3 ways a clinical diagnosis is made for myasthenia gravis?
Therapeutic testing (Edrophonium AKA Tensilon) Electromyography Serum assay for Ach receptor antibody (highly specific)
154
What are some treatments for myasthenia gravis?
Anticholinesterases High-dosage corticosteroids & plasma exchange (crisis situations) Thymectomy produces variable remission
155
Improvement from myasthenia gravis is least likely in which pts?
Pts w/ thymoma
156
This disease is caused by antibodies to calcium channels in the nerve endings. These antibodies block the flow of calcium & thus inhibit the transmission of nerve impulses
Lambert-Eaton Syndrome (myasthenic syndrome)
157
What cancer is Lambert-Eaton Syndrome sometimes assoc. w/?
Small-cell carcinoma of the lung (oat cell carcinoma)
158
How is Lambert-Eaton Syndrome characterized clinically?
Weakness of muscles in a distribution similar to myasthenia gravis w/ early involvement of occular muscles
159
How does Lambert-Eaton Syndrome differ from myasthenia gravis?
Muscle weakness is not aggravated by effort but rather the opposite
160
How does Clostridium botulinum (Botulism) affect neuromuscular transmission?
Blocks release of Ach at the motor end plate
161
How does botulism cause death?
Generalized muscle weakness rapidle leads to respiratory paralysis & death
162
Which type of ticks secrete a toxin that inhibits Ach release?
``` Dermacentor andersoni (Rocky Mountain wood tick) Dermacentor variabillis (American dog tick) ```
163
Benign tumors of the skeletal muscle typically originate from where?
Fibroblasts & blood vessels
164
What are some types of benign tumors of the skeletal muscle?
Hemangioma Beniign fibrous histiocytoma Lipoma Rhabdomyoma
165
Malignant skeletal muscle tumors are typically classified as what?
soft tissue sarcomas
166
This type of malignant tumor is found in striated muscle fibers most often found in children, is highly malignant but responds to chemotherapy
Rhabdomyosarcoma
167
This malignant tumor is a tumor of fibroblast & histiocyte-like cells. It is the M/C sarcoma of soft tissues
Malignant fibrous histiocytoma
168
What is a histiocyte?
A macrophage present in connective tissue
169
This malignant tumor is a tumor of fat cells found mostly in adults, may occur in low & high-grade forms
Liposarcoma
170
This is malignant tumor composed of undifferentiated mesenchymal cells, found in young adults, highly malignant & resistant to therapy
Synovial Sarcoma (has no connection to synovium)
171
This is a malignant tumor of smooth muscle cells, similar to uterine or GI smooth muscle cell tumors
Leiomyosarcoma
172
Why have muscular dystrophies been historically grouped together?
Have a genetic basis & occur in families Show preferential involvement of certain muscle groups Have a consistent clinical presentation, such as age of onset & progression of muscle weakness
173
How is the diagnosis of muscle diseases usually made?
Clinical exam EMG Serum enzyme levels
174
What serum enzyme levels are typically elevated in muscle diseases?
``` Creatine kinase (CK) Aldolase Lactate dehydrogenase (LDH) ```
175
Where is the preferred site of muscle biopsy?
Gastrocnemius
176
Where is the M/C quadrant for breast cancer?
In the lateral upper quadrant
177
What are the two types of breast cancer?
``` In Situ carcinoma (15-30% of cases) Invasive carcinoma (70-85% of cases) ```
178
What are the two major divisions of In Situ/Invasive carcinoma in breast cancer?
In Situ/Invasive Ductal carcinoma | In Situ/Invasive Lobular carcinoma
179
What are the two types of In Situ ductal carcinomas?
Comedocarcinoma | Non-comedocarcinoma
180
What are the 4 types of Non-comedocarcinoma?
Cribiform Micropapillary Papillary Solid
181
What are the common histologic types of Invasive ductal breast cancer?
Invasive Ductal cancer AKA Not otherwise specified Tubular cancer Colloid cancer Medullary cancer
182
What are the rare histologic types of invasive ductal breast cancer?
Papillary cancer Apocrine cancer Secretory cancer
183
What are the special types of invasive ductal breast cancer?
Pagets disease of the nipple | Inflammatory cancer
184
What is the difference b/w In Situ Ductal carcinoma and In Situ Lobular carcinoma
Calcifications are detected by mammography w/ Ductal whereas they are not w/ Lobular Lobular tends to be bilateral & M/C in young women
185
What is the difference b/w comedocarcinoma & non-comedocarcinoma?
Comedo is solid sheets of cells w/ central necrosis & is pleomorphic whereas Non-Comedo is monomorphic
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This pattern of breast tissue affected by Non-Comedo have holes w/ sharp margins as though punched out by a cookie cutter
Cribiform
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This pattern of breast tissue affected by Non-Comedo has small bumps or mounds of tumor cells to slender papillary structures.
Micropapillary
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This pattern of breast tissue affected by Non-Comedo is arranged in a "fern-like" pattern w/i the duct.
Papillary
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This pattern of breast tissue affected by Non-Comedo has nuclei that are enlarged, hyperchromatic, irregular in size & shape
Solid
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Which is the M/C form of Invasive Carcinoma; Ductal or Lobular?
Ductal (90%)
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This type of common histologic variant of invasive ductal carcinoma is AKA Scirrhous cancer & is the M/C common histologic variant (79%)?
Not Otherwise Specified (NOS)
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This type of common histologic variant of invasive ductal carcinoma is multifocal, bilateral, has an excellent prognosis, and affects women of about 40 yrs of age?
Tubular cancer AKA cribiform
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This type of common histologic variant of invasive ductal carcinoma is found mainly in older women & is slowly progressive
Colloid cancer AKA Mucinous
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This type of common histologic variant of invasive ductal carcinoma is well circumscribed w/ better prognosis than NOS & has no over expression of HER2/neu antigen
Medullary cancer
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HER2/neu stands for what & what is its function?
Human Epidermal growth factor Receptor 2 & is a protein giving higher agressiveness in breast cancers
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This is an uncommon variant of ductal carcinoma, either in situ or invasive, that extends to involve the epidermis of the nipple & areola
Paget disease of the nipple
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What is usually the initial presenting symptom of Paget disease of the nipple?
An eczematous (rash) change in the skin of the nipple & areola
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What is seen microscopically in Paget disease of the nipple?
Large cells w/ clear cytoplasm (Paget cells) found singly or in groups w/i the epidermis
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This is a type of tumor that arises in connective tissue of an organ (lipomas & angiosarcomas, etc)
Stromal tumor
200
In the breast, are stromal tumors benign or malignant?
They are usually benign but have malignant potential
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What are the two types of stromal tumors found in the breast?
Fibroadenoma | Phyllodes
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This type of stromal tumor is the M/C benign tumor of the female breast
Fibroadenoma
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At what age is fibroadenoma M/C?
20-35 yrs of age
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Fibroadenoma enlarge more rapidly during _______ & stop growing after ________
Pregnancy; menopause
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What is the subsequent risk of invasive CA in a breast that has had a fibroadenoma removed?
Doubled
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The diagnosis of malignant phyllodes is based upon what?
The stromal component growing out of proportion to the benign ductal element
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What part of a phyllode tumor metastasizes?
Only the stromal component; spreads via blood to the lungs & other organs
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What is the age range of females affected by a phyllode tumor?
30-70 w/ a peak in the 5th decade
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What are two genes implicated in breast as well as ovarian cancers?
BRCA1 & BRCA 2
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What is the function of BRCA1/BRCA 2 genes?
Tumor suppresor genes & function as DNA repair genes | Thought to bind RAD51, a molecule that mediates DNA double-strand break repairs
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Which gene is especially assoc. w/ male breast cancer?
BRCA2
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Vulvular intraepithelial neoplasia carcinoma in situ (VINIII; most severe form) is AKA?
Bowen Disease
213
What disease is present in 90% of pts w/ Vulvular intraepithelial neoplasia?
HPV
214
What is the M/C carcinoma in the vagina in the 60-70 age group?
Squamous cell carcinoma
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This carcinoma is typically rare but often seen in young women whose mothers were treated w/ Dietylstilbesterol (DES) during pregnancy (for a threatened abortion)
Adenocarcinoma
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This is an ascending infection that begins in the vulva & usually spreads upward through the entire genital tract
Pelvic Inflammatory Disease (PID)
217
What are the 3 known causes of PID?
Gonococcus (M/C) Postabortal & postpartum PID (staph, strep, coliform bacteria, etc) Chlamydial infection
218
What are complications of PID?
Peritonitis Intestinal obstruction Infertility Ectopic tubal pregnancy
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What is one of the M/C tumor in the cervix for the 40-45 age group?
Invasive squamous cell neoplasia (CIN)
220
What is CIN usually preceded by?
Cervical dysplasia seen in 30 yr age group
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What are risk factors for CIN?
1st intercourse at an early age Multiple partners Viruses like herpes II Bacteria, tobacco use
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What is the M/C gynecological problem?
Excessive bleeding during or b/w menstrual periods
223
What are some causes of excessive bleeding during or b/w menstrual periods?
Lack of ovulation resulting from endocrine disorders such as thyroid, adrenal disease, pituitary tumor Primary lesion of the ovary such as polycystic overies or a functioning estrogenic ovarian tumor Obesity or malnutrition
224
Chronic endometriosis occurs in pts suffering from what?
PID TB Retained gestational tissue after abortion IUD
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This refers to the presence of endometrial glands & stroma w/i the mymetrium
Adenomyosis
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What does adenomyosis cause?
Uterine enlargement & irregular thickening resulting in pain, dysmenorrhea, or menorrhagia
227
What is the most significant correlation seen in adenomyosis?
Glands are located 2mm or more into the myometrium
228
This refers to the presence of endometrial glands or stroma in abnormal locations outside the uterus. Causes dysmenorrhea & female infertility
Endometriosis
229
What is required for a definite histologic diagnosis of endometriosis?
Endometrial glands in the ectopic lesions Stroma in the ectopic lesions Hemosiderin pigment in the ectopic lesions
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This refers to metastatic ovarian cancer (usually bilaterally) composed of mucin-producing SIGNET cells that metastasize from the GI tract (mainly stomach)
Krukenberg Tumors
231
What is a good indicator that ovarian tumors are secondary & not primary?
If they are bilateral, then they're likely to be secondary
232
What is the best example of hereditary nephritis?
Alport Syndrome
233
What is Alport Syndrome usually assoc w/?
Nerve deafness Lens dislocation Cataracts Corneal dystrophy
234
What is the pathogenesis of primary glomerulonephritis?
Anti-glomerular basement membrane | Heymann Nephritis
235
What is Heymann Nephritis?
Antibodies react w/ an antigen on the visceral epithelial cells containing a protein called megalin
236
This is when changes are assoc. w/ sclerosis of renal arteris due to essential hypertension &/or diabetes. Rarely results in kidney failure
Benign Nephrosclerosis
237
What is the M/C testicular tumor?
Seminona
238
90% of testicular tumors are of what cell origin?
Germ cell origin
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A testicular teratoma is almost always _______ whereas the corresponding ovarian teratoma (Dermoid cyst) is almost always _________
Malignant; Benign
240
Teratomas are composed of derivatives of what germ layers?
Ectoderm Endoderm Mesoderm
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Embryonal cercinoma cells are the cells of most what?
Nonseminomatous germ cell tumors
242
Embryonal carcinoma cells that differentiate into somatic tissues & extraembryonic tissue form heterogenous tumors called?
Teratocarcinomas
243
If embryonic carcinoma cells differentiate into only trophoblastic cells, the tumor is called?
Choriocarcinoma
244
If embryonic carcinoma cells differentiate into only yolk sac cells, the tumor is called?
Yolk sac carcinoma
245
If the embryonic cells differentiate into somatic tissue, the tumor is called?
Teratoma
246
What is another name for a benign teratoma?
Dermoid Cyst
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This is AKA benign nodular hyperplasia
Benign prostatic hyperplasia
248
Benign Prostatic Hyperplasia is due to what 2 causes?
Greater the level of dihydrotestosterone, the larger the size of the prostate Age-related increase in estrogens which promote expression of receptors for dihydrotestosterone
249
Inhibition of what enzyme is employed for treatment of BPH?
5 alpha-reductase
250
Prostate cancer may progress to ______ which usually sees an increase in alkaline phosphatase levels
Osteoblastic metastasis