Quiz 5 Flashcards
(137 cards)
1
Q
Process that results when a nerve fiber is cut or crushed, where the part of axon separated from neuron’s cell body degenerates distal to the injury:
A
Wallerian degeneration
usu begins within 24-36 hrs of injury
2
Q
PNS dz is divided into 2 main categories:
A
- mononeuropathies - affect single peripheral nerve
* polyneuropathies - more than one peripheral nerve, and often diffusely affect PNS
3
Q
MC cranial mononeuropathies:
A
- VII (facial)
- V (trigeminal)
- III (occulomotor)
4
Q
Acute idiopathic facial nerve neuropathy, aka _________ is the MC cranial nerve neuropathy. The main sx is:
A
Bell’s Palsy
unliateral facial weakness - abrupt onset preceded / accompanied by pain on the affected side.
Mb Hx of URI in the past 1-3wks
5
Q
Bell’s palsy is an (upper/lower) motor neuron condition and affects the (upper/lower) face. It is thought to be post-infx or via direct viral infx, with _______ being the suspected etiologic agent.
A
lower
both
HSV1
6
Q
85% of pts w/Bell’s palsy recover fully in 1 year. Clinical features assoc w/poor prognosis include:
A
- old age
- complete palsy (vs weakness)
- hyperacusis (sound sensitivity)
- altered taste
7
Q
Distinctive facial pain syndrome in which pt experiences intense, paroxysmal pain, ranging from infrequent to dozens of times daily:
A
Trigeminal neuralgia (tic douloureux)
8
Q
Trigeminal neuralgia mb caused by:
A
blood vessel compression of trigeminal n. roots at pons
if caused by tumor - called secondary TN
9
Q
MC blood vessel responsible for trigeminal neuralgia:
A
superior cerebellar artery
10
Q
Since they control most of the eye movements, cranial nerves ___ ___ and ___ are usu tested together.
A
CN III, IV, and VI
tested by EOMs
11
Q
CN III palsy is characterized by:
A
“down ‘n out” sx - lateral, downward deviated gaze
12
Q
Mononeuropathies of limb nerves are MC related to:
A
physical nerve compression:
- carpal tunnel syndrome
- ulnar neuropathy
- brachial plexus neuropathy
- peroneal neuropathy
- meralgia paresthetica
13
Q
MC sx of Carpal Tunnel:
A
intermittent numbness of thumb/index/middle/1/2 ring finger
(often at night)
may lead to constant numbness, atrophy, weakness
14
Q
Condition characterized by sensory symptoms in lateral cutaneous nerve distribution of the thigh, with combo of sensory loss, prickling paresthesia, and hypersensitivity over the anterolateral thigh:
A
Meralgia paresthetica
15
Q
Meralgia paresthetica is usu attributed to:
A
compression of the lateral cutaneous n. by inguinal lig as it passes from retroperitoneum to anterior thigh.
(more common in obese)
16
Q
MC peripheral neuropathy common in DM:
A
polyneuropathy -
- distal
- symmetrical
- sensorimotor
17
Q
Classic diabetic neuropathy distribution:
A
“glove-and-stocking” - combo of sensory loss, numbness, and burning
18
Q
______ and _____ to nerves mb the most important underlying cause of diabetic polyneuropathy, but another proposed mechanism is chronic _________ leading to accumulation of _______ and the depletion of _______ in the affected nerves, leading to altered conduction in axon.
A
ischemia and hypoxia
hyperglycemia
sorbitol
inositol
19
Q
The chief pathologic finding in uremic neuropathy is ____________, which is most abundant in the most distal aspects of the PNS. Risk is related to duration and severity of _____________, and improvements are usu seen in:
A
axonal degeneration
renal failure
dialysis and renal transplant
20
Q
MC immune or inflammatory polyneuropathy and MC cause of acute generalized paralysis in the US:
A
Guillan-Barre syndrome (GBS)
21
Q
MC first sx of GBS:
A
prickling parasthesia - from feet, spreading up legs
22
Q
Condition in which the fundamental pathologic event is stripping of myelin from axons by macrophages, which slows or blocks nerve impulse conduction, causing weakness and sensory loss:
A
chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)
23
Q
(Similar/contrary) to GBS, the onset of CIDP is insidious, and autonomic and respiratory involvement is (common/unusual).
A
Contrary
unusual
usu pattern of CIDP is slow worsening over months, producing chronic moderate disability.
24
Q
Polyneuropathy characterized by amyloid deposition in nerve:
Occurs in 2 settings:
A
amyloid neuropathy:
- systemic amyloidosis
- familial amyloidosis
dx by nerve biopsy
25
T/F: Neuropathy is usu the MC of disability in primary amyloidosis unlike familial amyloid patients where neuropathy is generally less severe.
false / opposite
MC cause of disability in familial amyloid pts.
26
T/F: Neurologic deficits that mb seen as a consequence of paraneoplastic syndromes are a result of metastasis to involved nerve(s).
false - are NOT a result of mets
believed to be immunologic response
27
Toxic neuropathies tend to begin ________ and progress over _______________.
distally
weeks to months
* from chemicals, drugs, natural compounds
28
Main feature of toxic neuropathy:
axonal degeneration
| * biopsy not helpful *
29
Danish beer is supplemented with:
thiamine and pyridoxine - unlikely that deficiency is the cause of ethanol neuropathy (cause unclear)
30
Characteristic of chronic alcoholic neuropathy:
* distal
* usu painful (burning, stabbing)
* dec sensation in feet (mb hands)
* loss of ankle reflexes
* mild distal weakness
31
T/F: Drug-induced neuropathy is a common problem.
true - esp in a hospital-based practice!
careful drug Hx important in work-up
32
In some drug related neuropathies, the patient experiences the phenomenon known as "coasting", which is:
neuropathy continues to worsen for weeks after exposure to the drug has ceased.
33
Peripheral neuropathy d/t lead exposure is predominantly (sensory/motor), with a predilection for the (upper/lower) limbs.
motor
| upper
34
Polyneuropathy can be a manifestation seen in famine victims or as a result of ________ related to ________. Exact cause is unclear, although it is often though to relate to one of the __ vitamins.
malnutrition
malabsorption
B
35
Paralytic illness caused by neurotoxins of anaerobic, spore-forming bacterium:
Botulism - Clostridium botulinum
36
Botulinum neurotoxins work by:
inducing blockage of voluntary motor and autonomic cholinergic neuromuscular junctions -> prevent motor fiber stimulation
37
Infectious dzs assoc w/ PNS neuropathies:
* leprosy - MC
* HIV/AIDS
* lyme dz
* VZV
38
Most prevalent tick-borne illness in the US:
Lyme dz - named for Lyme, CT where outbreak was recognized in '75.
Vector - Ixodes spp. tick
39
T/F: B. burgdorferi is a gram-neg bacteria that is rapidly reproducing.
false
does not hold any stain - unclassified
slow reproducing - once in 12-24 hours!
40
Characteristic rash of Lyme dz:
erythema migrans - target lesion
41
T/F: Unlike pts with Bell’s palsy, BL facial neuropathy is MC in pts with Lyme disease.
TRUE
42
MC viral pathogen affecting the PNS:
VZV - usu after childhood exposure, virions lay dormant in dorsal root or cranial ganglia. Reactivation = shingles.
43
Classic herpes zoster (shingles) manifestation:
* dematomal pain
* vesicular eruption 3-14 days later
- last 7-10 days, area left depigmented, scarred
* mb weakness, sensory loss
44
Histopathology of herpes zoster:
* multinucleated giant cell
| * nuclear accentuation
45
Herpes zoster ophthalmica is often preceded by a lesion:
on the tip of the nose (Hutchinson's sign)
46
Examination of the ____ should be performed on all shingles pts with face/nose involvement, dt likelihood of ________.
eye
| corneal ulceration
47
When shingles is assoc w/facial paralysis it is called:
Ramsay-Hunt syndrome
48
When Schwann cells (that myelinate axons) proliferate out of control, the resultant bundle of cells is called a:
schwannoma
benign but detrimental when tumor compresses nerve
49
Benign primary intracranial tumor of the myelin-forming cells of the vestibulocochlear nerve (CN VIII):
vestibular schwannoma - aka acoustic neuroma
50
Common, benign spindle cell tumor of peripheral nerves:
neurofibroma
51
MC nerve affected with neurofibroma type I:
CN VIII
unilateral, look for cafe au lait skin spots
52
Neurofibroma type II is the result of mutation of protein ______ and manifests with bilateral _____________.
merlin
neuromas and hearing loss
hallmark - usu around age 20
53
Histopathology of perineuromas:
* elongated cells
* parallel bundles
* no atypia
* rare mitotic figures
54
Malignant tumor that usu arises from major nerves in the neck, forearm, lower leg, or buttocks:
malignant peripheral nerve sheath tumor (MPNST)
50% assoc w/underlying neurofibromatosis / 50% de novo
55
Histopathology of MPNST:
* increased cellularity
| * disordered arrangement
56
The brain devotes most of its volume and energy to processing received __________ and initiating/coordinating ___________.
sensory inputs
| motor outputs
57
From outside in, the meningial layers are:
dura mater
arachnoid mater
pia mater
58
The CSF fills the space between which layers?
arachnoid and pia
59
Birth defects involving what organ are the MC?
brain
| although defects leading to infant death it is #3, after heart and lungs
60
Absence of brain formation:
Anencephaly (neural tube defect)
61
Diminished forebrain size:
Microcephaly
62
Absence of gyri:
Agyri
63
Increased number of smaller than normal, shallow gyri:
Polymicrogyri
64
Enlarged abnormal gyri:
Macrogyri / pachygyri
65
Anencephaly has dropped to 1 in 10K incidence d/t:
maternal folic acid supplementation
66
Some causes of microcephaly:
* fetal alcohol syndrome
* trisomy 18 (Edward's syndrome)
* congenital Rubella
* congenital HIV
persons w/Down's have dec volume w/ disproportionate small cerebellum, larger sub-cortical grey matter
67
MC cause of hydrocephalus:
obstruction of normal CSF flow
| * mb 2° to malformations, tumors, hemorrhage, infx
68
Failure of normal closure of the vertebral column and/or overlying skin over the dorsal aspect of the spinal cord:
Spina bifida
* occulta
* myelocele
* myelomeningocele
69
Spina bifida occulta:
missing a portion of a posterior vertebral body.
70
Meningocele:
herniation of the meninges but not cord.
71
Myelomeningocele:
herniation of the meninges and spinal cord.
72
100% of pts with myelomeningocele have:
tethered cord - result of scar tissue post surgical repair
73
AFP can be measured in:
* serum
* urine
* amniotic fluid
74
Maternal AFP is typically measured at:
14-16 weeks gestation
75
T/F: AFP is considered to be the fetal form of serum albumin.
true
the function of AFP in adults in unknown
76
Principle tumors that secrete AFP:
* non-seminomatous germ cell tumors
* neuroblastoma
* hepatoblastoma
* hepatocellular carcinoma
77
Maternal AFP elevation mb seen in:
* multiple gestation
* placental abruption (separation)
* neural tube defects
* abdominal wall defects
* miscalculation of gestational age
* MTHFR genetic variant mothers
78
Low maternal AFP mb seen in:
* Down syndrome
| * Trisomy 18
79
T/F: Developmental deficits and brain injury in children with congenital heart disease is a serious problem and mb seen in more than 1/3 of these newborns.
true - In the U.S., ~30K are born/year with congenital heart dz, and ~50% will require open-heart surgery.
unclear if brain injury occurs prior/during/after cardiac surg.
80
Group of permanent disorders of the development of movement and posture, which cause activity limitation, attributed to non-progressive disturbances in the developing fetal or infant brain:
Cerebral palsy
* during pregnancy - 75%
* during birth - 10%
* after birth - 15%
81
Intrauterine development of CP has been assoc with :
maternal infx
* Strep. throat
* maternal CNS infx
82
After birth, CP mb caused by:
* severe jaundice
* encephalitis
* meningitis
* toxins (lead)
* physical injury (SBS)
* brain hypoxia
83
MC type of CP:
spastic - 70-80% of cases
84
At a cellular level, damage to the brain in spastic CP affects the nervous systems ability to receive ______________ in the brain area affected.
gamma amino butyric acid
85
The MC finding on autopsy of newborns / infants with CP is:
periventricular leukomalacia - PVL
| necrosis around the ventricles d/t hypoxia and anoxia
86
Children with PVL have higher levels of:
* nystagmus
* strabismus
* optic nerve hypoplasia
* refractive error
87
Aseptic meningitis is a term for (non-/bacterial) meningitis, which the other is often called:
non-bacterial
| bacterial = purulent meningitis
88
MC cause of meningitis:
viral infx - usu resolve w/out tx
89
2nd MC cause of meningitis:
bacterial infx - often results in death or brain damage
90
MC presenting sx of meningitis:
1st - Headache
2nd - neck stiffness
* rapidly spreading petechial rash mb 1st in MM *
91
MC bacterial cause of meningitis in neonates:
* * E. coli **
* Streptococcus group B
* Listeria monocytogenes
92
MC bacterial cause of meningitis in infants/children:
* * Neisseria meningococci **
* strep pneumoniae
* H. influenza (HiB) (peak@6-9mos)
93
MC bacterial cause of meningitis in adolescents/adults:
* * Neisseria meningococci **
| * strep pneumoniae
94
MC bacterial cause of meningitis in older adults (65+):
* * Strep pneumoniae **
* Neisseria meningococci
* Listeria monocytogenes
* mycobacteria
95
If meningitis pt is immunocompromised, also test for:
* toxoplasmosis
* EBV
* CMV
* JC virus
* fungal infx
96
Who is at particular risk for infx by encapsulated organisms such a Neisseria meningitis and H. flu?
Pts without a spleen!!
97
CSF is typically drawn btw what spinal vertebrae?
Lumbar 3 and 4
98
Which strain is latex agglutination most sensitive for:
```
** H. influenza (HiB) **
also test for
- strep pneumoniae
- N meningitidis
- E coli
- GBS
```
99
Meningococcal meningitis (MM) is another name for:
Neisseria meningitidis meningitis
100
Histopathology of meningococcal meningitis:
* gram neg diplococci in a neutrophil
| * prominent dilated blood vessels
101
Complications of MM:
* permanent brain damage
* possible mental retardation
* hydrocephalus
* deafness
* muscle paralysis
* myocarditis
* Waterhouse-Friderichsen syndrome
* death
102
Gross inspection of MM:
yellow-tan clouding of meninges d/t exudate (acute)
103
CSF analysis in bacterial meningitis shows:
* possible high WBCs w/PMN predominance
* low glucose
* usu gram + / culture +
104
Describe the rash of MM:
* mb first sx
* rapid spreading
* small irreg red/purple spots
* trunk/LE/mucous membranes/conjunctiva/palms/soles
105
HiB meningitis may follow a ____ and spreads:
URI
| from resp tract to blood to meninges
106
Risk factors for HiB meningitis:
* recent URI/OME/sinusitis/pharyngitis
* family members w/HiB infx
* daycare
* Native American / Eskimo race
107
Pt who recover from HiB meningitis may have long term:
* hearing loss
* seizures
* mental retardation
* hydrocephalus
* learning disorders
* behavioral problems
* speech / language development abn
108
What is aseptic meningitis?
Pt with ssx of meningitis with negative CSF culture
* viral
* fungal
* TB
* meds
* epidural abscess
109
What two enteroviruses account for 1/2 of the cases of aseptic meningitis?
Coxsackie B and echovirus
others:
* VZV
* polio
* mumps
* rabies
* HIV
* HSV 1 and 2
* EBV
* CMV
110
HSV type ___ can cause meningitis in children, especially _______, and adults.
types 1 and 2
| infants
111
______________ is a yeast that may cause meningitis, particularly in _____________ people.
```
Cryptococcus neoformans
immunocompromised
* AIDS
* lymphoma
* diabetes
```
112
MC life threatening fungal pathogen that infects AIDS pts:
cryptococcus neoformans
- soil fungi
- MC in Africa
- primarily affects lungs
- usu no neck stiffness
- mb papilledema (1/3)
113
Dx of Cryptococcal meningitis involves:
* yeast on CSF stain with INDIA INK
* CSF culture
* CSF + for cryptococcus antigen
114
Histopathology of cryptococcus neoformans:
** encapsulated cells (India ink) **
115
Most cases of viral encephalitis arise as a complication of:
common systemic viral infections (2-12 days post infx)
116
Name seasonal viral meningitis/encephalitis correlations:
* arboviruses - spring/summer
* enteroviruses - late summer
* mumps / varicella - spring
* HSV - not seasonal
117
MC cause of viral meningitis in children:
| Previous MC cause:
Enteroviruses (present)
| Mumps (past)
118
MC cause of viral meningitis in adults:
| 2nd MC:
** Enteroviruses **
| HSV type 2
119
T/F: Enterovirus refers to the sx of infx.
false - refers to mode of transmission, mostly asx
120
MC cause of sporadic encephalitis in developed countries:
HSV
type 2 - almost all adult cases
type 1 - more commonly in infants, infx via vaginal birth
121
Encephalitis d/t HSV infx characteristically involves the _________ lobes.
temporal
122
Gold standard for dx of carcinomatous meningitis:
detection of tumor cells in CSF
123
MC non-hematologic cancers that mets to CNS:
* lung
* breast
* melanoma
mb also head/neck/GI/GU
124
MC histologic type of carcinomatous meningitis:
adenocarcinoma
125
MC cerebral sx in carcinomatous meningitis:
| MC cranial nerve sx:
headache
| diplopia
126
T/F: Fever is often present with carcinomatous meningitis.
false - rarely unless there is a supervening infx
127
Describe the protective and harmful characteristics of brain abscess.
Protective - area of infx becomes enclosed in a membrane.
| Harmful - mass effect, puts pressure on surrounding tissue.
128
Histopathology of Aspergillus brain abscess:
slender hyphae which branch at 45° angles
129
Brain abscesses are MC in what decades?
| Higher in what populations?
first 4
| AIDS and other immunocompromised
130
T/F: In 80-90% of brain abscesses, only one organism is identified.
false - usu more than one
| mb bacterial, fungal, or parasitic
131
MC organism found in brain abscesses:
| gram stain MC in infants:
streptococcal
| gram -
132
MC neuro-parasitic infx in humans is a CNS infx by larvae of the pork tapeworm, Taenia solium:
Neurocysticercosis
133
Neurocysticercosis has a worldwide distribution, but MC in:
* Central and Latin America
* Mexica
* Asia
* Africa
* Spain
* Portugal
* Eastern Europe
134
The only definitive host of T. solium is:
humans (pig is intermediate)
135
Describe the mechanism of neurocysticercosis infx.
pig ingests eggs, which grow in GI, burrow into circulation, and encyst in tissues/brain. humans ingest tapeworms and are infected.
* humans can be intermediate host also, if ingest eggs, which can then burrow into brain => neurocysticercosis
136
CT of neurocysticercosis:
multiple, small nodular, and annular areas of abn enhancement in brain parenchyma.
137
Diet not working?
swallow a tapeworm!
| the end!!
