Pathology Flashcards
The Nissl stain is for ________ and binds ______.
neuronal bodies
nucleic acid
Lipofuscin accumulates in neurons due to ____.
aging
True melanin is made by _______ and is located in the _______.
tyrosinase
leptomeningeal melanocytes of the ventral medulla and cervical cord
Cytotoxic edeme is caused by ________.
impaired Na/K ATP pump
What is Ferruigination?
when dead neurons become encrusted with Fe and Ca
When does central chromatolysis occur?
injury to an axon near the cell body
What occurs in chromatolysis?
Nissl substance disappears, the nucleus becomes eccentric, and the cell body enlarges
cells may recover or progress to death
Silver stain stains ______.
cellular processes
Neurofibrillary tangles can be seen on what stain?
sillver stain
Subacute pansclerosing encephalitis is caused by _______.
measles
What viral infections have intranuclear inclusion bodies?
HSV 1, CMV, measles (the last two also have cytoplasmic inclusion bodies)
What are negri bodies? When are they seen?
intracytoplasmic inclusion bodies
rabies
Metabolic/degnerative inclusion bodies are all _______.
intracytoplasmic
Lewy bodies are seen in ______ and have a characteristic ______. They are located in the ______.
Parkinson’s disease
halo
cytoplasm
Lafora bodies can be stained with ______.
PAS
Hirano bodies are seen in _______ and are most commonly seen in the brain in the _______.
alzheimer’s disease
hippocampus
What are Bunina bodies?
intracytoplasmic inclusion bodies seen in ALS
What is a hamartoma?
disorganized cells located in the proper location
What is a choristoma?
properly organized cells in the wrong location
What causes duret hemorrhages during herniation?
arteriole stretching
What causes the Kernohan’s notch presentation?
contralateral cerebral peduncle compressed against the incisura
<p>What are rosenthal fibers?</p>
<p>eosinophilic masses in the astrocytic processes</p>
<p>Where are rosenthal fibers seen?</p>
<p>Pilocytic astrocytomas, Alexander disease, and reactive (secondary) astrocytosis</p>
<p>What are alzheimer type II astrocytes? When are they seen?</p>
<p>type of primary astrocytosis; large vesicular gray nuclei with glycogen inclusions in the cytoplasm</p>
<p></p>
<p>hepatic encephalopathy</p>
<p>When ependymal cells are injured, what replaces them?</p>
<p>subependymal astrocytes</p>
The brain and spinal cord are embryologically derived from _____ during weeks ______.
neuroectoderm
3-8
Primary neurulation occurs at ______.
3-4 weeks
What induces the primitive streak to form the neural plate?
notochord
The primitive streak forms POD ____.
POD 13
The notochord forms POD _____.
POD 17
The neural folds fuse on ______ to form _____.
POD 22
neural tube
The primitive streak forms the _____ which forms the _____ which forms the ______.
neural plate
neural groove
neural folds
The anterior neuropore closes on ______ forming the _______.
POD 24
lamina terminalis
Posterior neuropore closes on _____.
POD 26
What is dysjunction?
separation of the ectoderm from neuroectoderm after the neural tube forms
What happens when dysjunction occurs to early?
mesenchyme can enter the neural tube and form lipomas and lipomyelomeningoceles
Focal failure of dysjunction causes _______.
epithelial lined dermal sinus tract
Widespread failure of dysjunction can cause ______.
myelocele or myelomeningocele
Secondary neurulation occurs at _______ (days/weeks)
4-5 weeks
Problems with secondary neurulation cause _____.
spinal dysraphism below L1/2
What is ventral induction? When does it occur?
5-10 weeks PO; primary vesicles form from the neural tube
Abnormalities during ventral induction cause ________.
holoprosencephaly, septic optic dysplasia, and dandy walker malformation
Neuronal proliferation, differentiation, and migration occur around _______.
2-5 months
When does myelination start? When does it end?
5 months prenatalby 2 years post natal
What is the progression of myelination during CNS development?
caudad to cephalad, dorsal to ventral, central to peripheral, and sensory before motor
The prosencephalon divides into ________.
telencephalon and diencephalon
What structures arise from the telencephalon?
hemispheres, caudate, putamen, fornices, anterior commissure, corpus callosum, and hippocampus
What structures arise from the diencephalon?
thalamus, globus pallidus (GP), posterior hypophysis, infundibulum, optic nerve, retina, posterior commissure, and habenular commissure
The mesencephalon forms the ______.
midbrain
The rhombencephalon divides into ________.
metencephalon and myelencephalon
The metenecephalon forms the ______.
pons, fourth ventricle, and cerebellum
The myelencephalon forms the ______.
medulla
The germinal matrix forms at _______ and involutes at _______.
7 weeks GA
30 weeks GA
What is the directionality of the formation of the corpus callosum?
front to back except for the rostrum which forms last
What are the basal and alar plates?
prelimary structures to the brainstem
The basal plate contains somatic, special, and visceral _______ while the alar plate contains _______.
efferent
afferents
Which subset of nuclei lie the most medial on the basal and alar plates?
somatic efferents/afferents
What is formed from the neural crest cells?
leptomeninges, Schwann cells, sensory ganglia of the CNs, dorsal root ganglia (DRG), autonomic nervous system ganglia, the adrenal medulla, melanocytes, and amine precursor uptake and decarboxylation (APUD) cells
What is derived from the ectodermal placodes?
olfactory epithelium, CN V and CN VII to CN X ganglia
Chordomas are believed to embryologically derive from _______.
notochord remnants
The dura is derived from what embryological layer?
mesoderm
The pia/arachnoid are derived from what embyrological layer?
neuroectoderm
When does the metopic suture close?
around 1 year
When does the anterior fontanelle close?
around 2.5 years
When does the posterior fontanelle close?
2-3 months
When does the sphenoid fontanelle close?
2-3 months
When does the mastoid fontanelle close?
around 1 year
What is a malformation?
when an organ is not formed properly
What is dysplasia?
when tissues are not formed properly
What is the most common congential malformation?
anencephaly
In anencephaly, what is increased in the amniotic fluid?
AFP and acetylcholinesterase
What is craniorachischisis?
complete exposure of the brain and spine (think extreme anencephaly)
What two drugs are associated with an increased risk of myelomeningocele?
valproic acid and carbamazepine
What is the most frequent type of encephalocele in Southeast Asian communities?
Sincipital (frontoethmoidal) encephalocele
Which type of encephalocele is associated with dermoids and epidermoids?
Sphenoehtmoidal (nasal) encephalocele
What is the most common type of encephalocele in the West?
occipital encephalocele
What is Meckel Gruber syndrome? What is a risk factor?
characterized by cystic dysplastic kidneys, cardiac anomalies, orofacial clefting, and cephaloceles
maternal hyperthermia on days 20–26 of gestation
What percent of dermal sinus tracts end in epidermoids or dermoids?
50%
What are the most common locations for dermal sinus tracts?
lumbar followed by occipital
What is arrhinencephaly? What diseases is it associated with?
absence of the olfactory bulbs and tracts with normal cortex and gray matter in place of the corpus callosum
Kallman’s syndrome and holoprosencephaly
What’s another name for de Morsier’s syndrome?
septooptic dysplasia
What is septooptic dysplasia?
mild lobar holoprosencephaly, absence of the septum pellucidum, schizencephaly, and hypoplastic optic nerves
associated with seizures, visual symptoms, hypothalamic–pituitary dysfunction (precocious puberty), enlarged ventricles, and hypotelorism
What is cleidocranial dysostosis?
occurs with retention of mandibular teeth, delayed closure of fontanelles, wormian bones, and midline defects
Posterior fossa arachnoid cyst (will/will not) fill with intrathecal contrast.
will not fill
What is Lhemitte Duclos disease?
hypertrophied cerebellar granular cell layer and increased myelin in the molecular layer of the cerebellum with thick folia; considered a hamartoma
What syndrome is Lhemitte Duclos associated with ?
Cowden syndrome
What is the presentation of Cowden syndrome?
facial trichilemmomas, fibromas of the oral mucosa, hamartomatous polyps of the gastrointestinal (GI) tract and breast, and thyroid tumors (as well as cerebellum)
What is the genetic abnormality in Cowden syndrome?
PTEN mutation on Ch 10 (ten on ten)
What is syringobulbia?
fluid filled cavity in the brainstem
What is the inheritance of Crouzon syndrome?
AD or sporadic
What is the mutation in Crouzon syndrome?
fibroblast growth factor receptor 2
What is the presentation of Crouzon syndrome?
shallow orbits, exophthalmos, midface hypoplasia, malformed ears, agenesis of the corpus callosum, less severe mental retardation than with Apert syndrome, and increased incidence of hydrocephalus. More than one suture is involved, and they may have oxycephaly,turricephaly, or dolichocephaly
What is the mutation in Alpert syndrome?
fibroblast growth factor receptor
What is the presentation of Alpert syndrome?
more severe Crouzon; many whole body abnormalities; ONLY THE CORONAL SUTURE IS INVOLVED (turricephalic)
What is Klippel Feil syndrome?
congenital fusion of the upper cervical vertebrae
What is Klippel Feil syndrome associated with?
Sprengel’s deformity (elevation of the scapula) and Chiari I malformation
Which of the Trisomies is associated with rocker bottom feet?
18 (edwards)
Which of the trisomies is assoociated with polydactyly?
13 (Patau)
What is the mutation in cri-du-chat?
5p deletion
What cerebellar abnormality is seen in Fragile X syndrome?
vermian hypoplasia
What is the mutation in Fragile X syndrome?
trinucleotide repeat in FMR1 gene
What causes ataxia telengectasia?
defective DNA repair
What is the presentation of ataxia telengectasia?
characterized by cerebellar atrophy, lentiform nucleus calcifications, pachygyria, impaired immune system, increased lymphoreticular carcinoma
What is caput succedaneum?
cutaneous hemorrhagic edema in the skin over the calvarium caused by pressure during birth with vascular stasis. It crosses sutures and resolves in 48 hours
What is a cephalohematoma?
Subperiosteal blood that does not cross suture lines. It is usually parietal and may calcify
What is occpital osteodiastasis?
perinatal injury
traumatic separation of the squamous and lateral occipital bone with tearing of the occipital sinus and bleeding in the posterior fossa
What percentage of premature births have PIVH?
40%
What percent of full term births have PIVH?
3-7%
Where does PIVH originate from?
germinal matrix
What increases the risk of PIVH?
prematurity and ARDS
What is the morbidity and mortality of PIVH?
15-40%, 20-60%
What is colpocephaly?
dilated occipital horns associated with agenesis of the corpus callosum and periventricular leukomalacia, mental retardation, and seizures
What is status marmoratus?
thalamus, neostriatum, and cortex develop irregular intersecting bands of myelin and astrocytic fibers that grossly resemble marble caused by cell loss followed by remyelination
How is elevated bilirubin in neonates treated?
phototherapy using ultraviolet light, but if the bilirubin is > 20 with associated sepsis, prematurity, acidosis or low albumin, treat with an exchange transfusion
What lines the cavity in porencephaly?
gliotic white matter
What lines the cavity in schizencephaly?
grey matter
What is hydraencephaly?
cortex is mostly replaced by CSF (water head)
The most frequent pathogen overall for meningitis is _____.
H Flu
The most frequent cause of meningitis in adults is _______.
Strep pneumo
The three most common causes of meningitis are ________ and they normally colonize the ______.
H Flu, Strep pneumo, Neisseria meningitidis
nasopharynx
Most common cause of shunt infections is ______.
S. epidermidis
What is the mortality rate of the most common types of meningitis?
10% (H. influenzae and N. meningitidis), 25% (S. pneumoniae), and 50% (neonatal, with 50% of survivors having permanent sequelae
In the neonate period (<4 weeks), what are the three most common causes of meningitis?
Group B strep, E coli, and Listeria
What is the most common cause of meningitis in the 4-12 week period?
Strep pneumo
What is the most common cause of meningitis in the 3 month to 3 year period?
H flu
B/l subdural effusions is associated with what meningitic infections in infants? What is it due to? What can it cause?
H flu mostly and Strep pneumo
increased permeability of blood vessels
seizures
Steroids in meningitis has been show to do what?
decrease incidence of deafness in children
What is the most common cause of meningitis in children and young adults?
N meningitidis
What is the most common cause of meningitis in the elderly?
Strep pneumo
What is the most common pathogen for brain abscess?
streptococcus
What is the most common cause/source of cerebral abscess?
ear or sinus infection spreading along valveless venous channels (40%)
What percent of cerebral abscesses are secondary to hematogenous spread?
33%
What’s the incidence of brain abscess in cyantoic heart disease? What causes it?
5%
due to decreased pulmonary blood filtration and lower oxygen tension in the brain
What’s the incidence of brain abscess in hereditary hemorrhagic telangiectasia? What is the reason?
5%
presence of pulmonary AVMs
What are the most common pathogens of brain abscess in neonates?
Citrobacter, Bacteroides, Proteus, and Gram-negative bacilli
In trauma, what is the most frequent pathogen in brain abscesses?
Staph
What percent of subacute bacterial endocarditis develop infectious aneurysms?
10%
What are the most common pathogens in encephalitis?
Legionella (CSF culture is usually negative), Mycoplasma, Listeria (in neonates and immunosuppressed patients, CSF culture is usually positive), and Brucella
What are the most common pathogens for subdural empyema?
Streptococcus and Bacteroides from an adjacent infection
What is Gradenigo syndrome?
petrous apex osteomyelitis with CN VI palsy and retro-orbital pain and may occur in children from extension of severe otitis
Pathologic examintion in TB meningitis shows _____.
demonstrates granulomas with caseating necrosis, lymphocytes, and Langerhans giant cells
What is the morbidity and mortality of TB meningitis?
80% and 30%
The nervous system is involved in ______ of cases of sarcoidosis.
5%
________ levels are elevated in sarcoidosis.
serum ACE
What is Whipple disease? What is seen on pathology?
chronic multisystem disease caused by Tropheryma whippelii
characterized by weight loss, abdominal pain, diarrhea, lymphadenopathy, arthralgia, and Alzheimer’s disease-like neurologic symptoms (10%)
demonstrates foamy macrophages with PAS-positive granules
What percent of cases of syphillis involve the CNS?
25%
What are the four types of syphilis?
- Meningovascular syphilis
- general paresis of the insane
- tabes dorsalis
- Congenital syphilis
Which type of syphilis is associated with multiple ischemic strokes?
meningovascular
Which type of syphilis is associated with Argyl robertson pupils?
general paresis of the insane and tabes dorsalis
Which type of syphilis is associated with hutchinson’s triad? What is hutchinson’s triad?
congential and meningovascular
notched teeth, deafness, and interstitial keratitis
What are the features of tabes dorsalis?
occurs after 15–20 years from syphilis infection
characterized by myelopathy from meningealfibrosis; mainly dorsal root and posterior column involvement, W-shaped demyelination in the thoracic and lumbar spinal cord from the posterior horns inward, lightning-like pains, sensory ataxia, urinary incontinence, decreased lower limb deep tendon reflexes, decreased proprioception and vibratory sense, positive Romberg’s test, Argyll Robertson pupils (90%),ptosis, optic atrophy, and Charcot joints of the hip, knee, and ankle
What cranial nerve is most commonly affected in Lyme disease?
CN VII
What is the pathogen in Lyme disease?
Borrelia burgdorferi
What is the pathogen in syphilis?
Treponema pallidum
All fungi stain with ________.
methenamine silver
What is the most frequent CNS fungal infection?
Candida
Blastomycosis is associated with what part of the US?
eastern
Histoplasmosis is associated with what part of the US?
Ohio, Mississippi, and St Lawrence river valleys
What is the most frequent fungal meningitis?
Cryptococcus
Cryptococcus stains with ______ forming the distinct ______.
india ink
halos
What part of the US is Coccidioidomycosis from?
southwest
What is the pathogen in Cysticerosis?
Taenia solium
What is the most frequent brain mass in AIDS patients?
Toxoplasmosis
Congential toxoplasmosis lesions include ______.
brain necrosis, periventricular calcification, hydrocephalus, hydranencephaly, chorioretinitis, and hepatosplenomegaly.
What is the mortality in overall viral encephalitis?
5-20%
What is the mortality in HSV encephalitis?
50%
What is the incidence of permanent sequelae in patient’s who survive encephalitis?
20%
What is seen on pathology for viral encephalitis?
perivascular mononuclear infiltrates
HSV is found in the trigeminal ganglion in percent of adults?
50%
What is the most frequent cause of sporadic encephalitis?
HSV
What are Cowdry type A inclusions?
intranuclear eosinophilic masses with a surrounding halo found in neurons, oligodendrocytes, and astrocytes
seen in HSV and CMV
What are the pathologic findings in CMV?
Cowdry type A and intracytoplasmic inclusions
What findings are seen in congenital CMV infection?
microcephaly, hydrocephalus, chorioretinitis, and microphthalmia
What percent of shingles involve trigeminal nerve? which branch?
15% at V1
Herpes infection of the geniculate ganglion is called ______.
Ramsey Hunt Syndrome
What are the pathologic findings in Varicella?
Intranuclear inclusions in the DRG and the posterior horn gray matter, posterior roots, and meninges
What are Negri bodies? Where are they usually seen?
Intracytoplasmic eosinophilic collections of ribonucleoproteins
rabies infection in cerebellum (Purkinje cells), brainstem, and hippocampus
What are the symptoms of rabies infection?
Anxiety, dysphagia, and spasms of the throat when attempting to swallow (hydrophobia)
Which cells are most affected by polio virus?
anterior horn cells
What virus is associated with Progressive multifocal leukoencephalopathy (PML)?
JC virus
What inclusions are seen in PML?
intranuclear inclusions of “stick-and-ball” viral particles
What are the clinical findings in CJD?
myoclonus, pyramidal, and extrapyramidal degeneration, dementia, ataxia, and visual deterioration
What are the EEG findings with prion disease?
bilateral sharp waves of 1–2 wave/s that resembleperiodic lateralized epileptiform discharges, but are reactive to painful stimuli
What is seen on pathologic changes in prion disease?
spongiform changes with astrocytosis but no inflammation most prominently in the cortex, putamen, and thalamus
What is unique on pathologic examination of HIV encephalitis?
the presence of multinucleated giant cells
What is Rasmussen chronic encephalitis?
occurs in childhood and causes progressive deficits and seizures (classically complex partial status epilepticus) with unilateral atrophy. It may be caused by CMV infection or antibodies to glutamate receptors
What is the most frequent congenital CNS infection?
CMV
In the CNS, CMV has an affinity for ______ and causes ________.
germinal matrix
perivascular necrosis and calcifications
What is the triad of congenital toxoplasmosis infection?
hydrocephalus, bilateral chorioretinitis, and cranial calcifications
What is the most common late manifestation of congenital toxoplasmosis?
deafness
Congenital rubella syndrome consists of what clinical presentation?
chorioretinitis, cataracts, glaucoma, microphthalmia, microcephaly, mental retardation, and deafness
In congenital syphilis, what is hutchinson’s triad?
Dental disorders, bilateral deafness, and interstitial keratitis
<p>What percent of brain tumors are infratentorial in children?</p>
<p>70%</p>
<p>What are the most common infratentorial brain tumors in children?</p>
<p>cerebellar astrocytoma (33%), brainstem glioma (25%), medulloblastoma (25%), and ependymoma (12%)</p>
<p>What are the most frequent supratentorial brain tumors in children?</p>
<p>low-grade astrocytomas (50%), craniopharyngiomas (12%), and optic gliomas (12%)</p>
<p>In neonates and infants, are tumors more commonly supratentorial or infratentorial? What are the most common types?</p>
supratentorial
most common is teratoma, followed by primitive neuroectodermal tumors (PNETs), highgradeastrocytoma, and choroid plexus papilloma
<p>In older children, are tumors more commonly supratentorial or infratentorial? What are the most common types?</p>
<p>infratentorial
astrocytoma (50%), PNET (15%), craniopharyngioma (10%), ependymoma (10%), and pineal tumor (3%)</p>
<p>What is the genetic mutation in Turcot syndrome?</p>
<p>APC mutation on Ch 5</p>
<p>What is the triad of Turcot syndrome?</p>
<p>familial polyposis, colorectal cancer, and primary brain tumors</p>
<p>Synaptophysin stains tumors with \_\_\_\_\_\_.</p>
<p>neurons</p>