Quiz 5, Nervous System Flashcards Preview

Matthew Hicks Pathology IV > Quiz 5, Nervous System > Flashcards

Flashcards in Quiz 5, Nervous System Deck (83)
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1
Q

When a nerve injury occurs what response promotes the resealing of severed parts of the myelin sheath?

A

An initial calcium influx

2
Q

What is a process that results when a nerve fiber is cut or crushed, in which the part of the axon separated from the neuron’s cell body degenerates distal to the injury?

A

Wallerian degeneration

3
Q

Which three cranial nerves account for the majority of mononeuropathies?

A

7 - Facial
5 - Trigeminal
3 - Occulomotor

4
Q

What is the MC cranial nerve neuropathy?

A

Bell’s Palsy (acute idiopathic facial nerve neuropathy)

5
Q

What is the main symptom in Bell’s palsy?

A

Unilateral facial weakness that begins abruptly and preceded or accompanied by pain behind the ear.

6
Q

How do you differentiate Bell’s palsy from a stroke?

A

In a stroke the patient can still wrinkle their forehead, in bell’s palsy they cannot

7
Q

What condition is a distinctive facial pain syndrome felt over the maxillary or mandibular areas?

A

Trigeminal neuralgia (tic douloureux)

8
Q

What are some nutritional deficiencies and their related neuropathies?

A

Beriberi (B1) - alcohol
B6 deficiency - ?
B6 excess - ?
B12 - ?

9
Q

What blood vessel is most often responsible for neurovascular compression upon the trigeminal nerve root?

A

Superior cerebellar artery

10
Q

What condition is known for the “down ‘n out” symptoms?

A

Oculomotor nerve palsy (3rd CN)

11
Q

Which nerve is compressed and entrapped with carpal tunnel syndrome?

A

Median n.

12
Q

What can long standing carpal tunnel syndrome lead to?

A

Permanent nerve damage with constant numbness, atrophy/weakness of thenar eminence.

13
Q

Where is the most common site of ulnar nerve entrapment?

A

Elbow, followed by wrist.

14
Q

What is the “claw hand” deformity indicate?

A

Ulnar nerve injury. Effects 4th and 5th digits.

15
Q

What is meralgia paresthetica characterized by?

A

Sensory symptoms in the distribution of the lateral cutaneous nerve of the thigh

16
Q

Meralgia paresthetica is usually attributed to compression of the lateral cutaneous nerve by what structure?

A

Inguinal ligament as it passes from the retroperitoneum to the anterior thigh

17
Q

In what condition is peripheral neuropathy most commonly noted?

A

Diabetes mellitus

18
Q

What types of diabetes related neuropathies are most common?

A

Distal, symmetrical and sensorimotor neuropathies

19
Q

What is the chief pathologic finding in uremic neuropathy?

A

Axonal degeneration

20
Q

What is the most common cause of acute generalized paralysis in the U.S.?

A

Guillain-Barre syndrome

21
Q

What is the rate of onset in CIDP compared to GBS?

A

CIDP is insidious, GBS is more rapid initially

22
Q

How common is autonomic and respiratory involvement in CIDP compared to GBS?

A

Common in GBS

Unusual in CIDP

23
Q

What is the fundamental pathologic event in Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP)?

A

Stripping of myelin from axons by macrophages, which slows or blocks nerve impulse conduction.

24
Q

Polyneuropathy characterized by amyloid deposition in nerve generally occurs in one of what two settings?

A

Systemic or familial amyloidosis

25
Q

What mycobacterial disease, the majority of which occur in tropical and sub-tropical regions, is one of the most common causes of polyneuropathy worldwide?

A

Leprosy

26
Q

How does Borrelia burgdorferi stain?

A

Neither gram-negative nor gram-positive

27
Q

What cranial neuropathy is most common in lyme disease and what is it commonly misdiagnosed as?

A

Facial (bilateral)

Idiopathic Bell’s palsy

28
Q

What is the most common viral pathogen affecting the PNS?

A

Varicella-zoster

29
Q

What condition is caused by glial cells that myelinate axons proliferating and compressing nerves?

A

Schwannoma

30
Q

Vestibular schwannomas may occur as an idiopathic process or can occur as part of what syndrome?

A

Neurofibromatosis (type 1 or 2)

31
Q

What is a common, benign, spindle cell tumor of peripheral nerves?

A

Neurofibroma (solitary tumor suggests that the pt does not have neurofibromatosis)

32
Q

What condition follows the mutation of neurofibromin, a tumor suppressor gene?

A

Neurofibromatosis type 1

33
Q

Which type of neurofibromatosis is more common (90%) and also known as von Recklinghausen disease?

A

Type 1

34
Q

How do you differentiate type 1 from type 2 neurofibromatosis?

A

Type 1: Entire 8th nerve, cutaneous neurofibromas, cafe au lait spots
Type 2: bilateral acoustic neuromas > hearing loss

35
Q

What condition follows the mutation of the protein, merlin?q

A

Neurofibromatosis type 2

36
Q

What kind of tumors are characterized by elongated cells in parallel bundles?

A

Perineuromas

37
Q

What is a malignant schwannoma that usually arises from major nerves of the neck, forearm, lower leg, or buttocks?

A

Malignant peripheral nerve sheath tumor (MPNST)

38
Q

What are the histology keywords to associate with a malignant peripheral nerve sheath tumor that you have no hope of remembering after this test?

A
Monomorphic serpentine cells
palisading
large gaping vascular spaces
perivascular plump cells
geographic necrosis with tumor palisading at edges
39
Q

What type of birth defects are most common?

A

Those involving the brain (although those involving the heart are the MC defects leading to death)

40
Q

What is the absence of brain formation?

A

Anencephaly

41
Q

What is diminished brain size?

A

Microcephaly

42
Q

What are four potential causes of microcephaly?

A

Fetal Alcohol syndrome
Trisomy 18
Congenital rubella
Congenital HIV

43
Q

What is the most common cause of hydrocephalus?

A

Obstruction of normal CSF flow (it can also be caused by CSF production or reabsorption problems)

44
Q

Which spina bifida refers to a condition of a missing portion of a posterior vertebral body?

A

Occulta

45
Q

Which spina bifida refers to herniation of the meninges but not the cord?

A

Meningocele

46
Q

Which spina bifida refers to the herniation of the meninges and the spinal cord?

A

Meningomyelocele (myelomeningocele)

47
Q

What are some conditions seen with ABOVE normal levels of maternal alpha fetal protein?

A

Neural tube defects including spina bifida, anencephaly, and abdominal wall defects

48
Q

What are some conditions seen with BELOW normal levels of maternal alpha fetal protein?

A

Down’s syndrome and Trisomy 18

49
Q

What is the most common type of cerebral palsy?

A

Spastic, hypertonic musculature stemming from damage to the motor cortex, corticospinal tract or pyramidal tract

50
Q

What is the most common finding on autopsy of patients with cerebral palsy?

A

Periventricular leukomalacia (necrosis around the ventricles)

51
Q

With periventricular leukomalacia what becomes of the damaged areas?

A

Partly cystic and partly gliotic (gliosis)

52
Q

Which is more commonly the cause of meningitis, viral or bacterial infection? and which is more serious?

A

MC: Viral [resolves w/o tx]
2nd bacterial [may result in death/brain damage despite tx]
(can also be caused by cancer or trauma)

53
Q

What bacteria is MC cause of meningitis in NEONATES?

A

E. Coli

54
Q

What bacteria is MC cause of meningitis in INFANTS/CHILDREN?

A

Neisseria meningococci

55
Q

What bacteria is MC cause of meningitis in ADOLESCENTS/ADULTS?

A

Neisseria meningococci

56
Q

What bacteria is MC cause of meningitis in OLDER ADULTS?

A

Strep. pneumonia

57
Q

What does CSF analysis reveal in bacterial meningitis for CSF pressure?

A

> 180 mm H2O

58
Q

What does CSF analysis reveal in bacterial meningitis for WBC count?

A

10 - 10,000/ uL with notable neutrophil predominance

59
Q

What does CSF analysis reveal in bacterial meningitis for glucose and CSF to serum glucose ratio?

A
60
Q

What does CSF analysis reveal in bacterial meningitis for protein?

A

> 4.5 mg/dL

61
Q

What does CSF analysis reveal in bacterial meningitis for gram stain and culture?

A

Both are positive in a majority of cases

62
Q

What test is best for identifying viral meningitis?

A

PCR

63
Q

What test is best for identifying H. flu?

A

Latex agglutination

64
Q

What is typically seen on histology of Neisseria meningitidis?

A

Gram negative diplococci within a neutrophil

Neutrophilic exudate, dilated vessels

65
Q

What are some sequelae of meningococcal meningitis?

A
Permanent brain damage
Hydrocephalus
Deafness
Paralysis of various muscles
Myocarditis
Waterhouse-Frederichsen syn.
Death
66
Q

What clinical sign often precedes other symptoms with meningococcal meningitis?

A

Rapidly spreading petechial rash

67
Q

Although the development of a vaccine has greatly reduced its incidence what microorganism causing meningitis typically affects children under 4 following URI?

A

Haemophilus influenzae

68
Q

What two viruses account for most of the cases of aseptic meningitis?

A

Coxsackie B and echovirus

69
Q

What yeast found in soil around the world causes meningitis especially in the immunocompromised?

A

Cryptococcal neoformans (confirmed by CSF stains using India ink, culture, antigen test)

70
Q

What does viral encephalitis most commonly arise as a complication of?

A

Common systemic viral infections

71
Q

What type of viruses are predominantly noted in spring and summer months?

A

Arthropod-borne (arboviruses)

72
Q

What viruses peak in the late summer?

A

Enteroviruses

73
Q

When are mumps and varicella prevalent?

A

Spring

74
Q

What type of virus is the MC cause of viral meningitis? 2nd? 3rd?

A

Enteroviruses
2nd: HSV 2
3rd: VZV
(among cases where the cause is identified, which is a minority of them)

75
Q

Encephalitis due to HSV infection characteristically involves what part of the brain?

A

Temporal lobes

76
Q

What is definitive for diagnosis of carcinomatous meningitis?

A

Tumor cells detected in the CSF

77
Q

What is the most frequent histologic type of meningeal tumor?

A

Adenocarcinoma

78
Q

What is seen histologically in a aspergillus brain abscess?

A

Slender hyphae

79
Q

What is the most common organism found in brain abscesses?

A

Streptococcus

80
Q

Are gram negative or positive organisms more common in infants with brain abscesses?

A

Negative

81
Q

What condition is an infection of the CNS by larvae of the pork tapeworm and what is the name of the tapeworm?

A

Neurocysticercosis

Taenia solium

82
Q

What is the definitive host for taenia solium?

A

Humans, pigs are intermmediary

83
Q

If a human ingests eggs from taenia solium through fecal contaminated food what is the condition if the resulting larvae do not encyst in the brain?

A

Cysticercosis