Pathology Flashcards
What is this
ALS - degeneration of corticospinal tracts with sparing of other tracts
What is this
Friedrich’s ataxia: tract degeneration - Dorsal columns, spinocerebellar tracts, lateral corticospinal tracts and DRG
Most common hereditary ataxia
AR, Chromosome 9, Triplet repeat GAA, Frataxin
50% hypertrophic cardiomyopathy, severe scoliosis
What is this?
B12 or HIV
What is this?
Subacute combined degereration of the cord
What is this?
Tabes Dorsalis
Tabes dorsalis, also known as syphilitic myelopathy, is a slow degeneration (specifically, demyelination) of the neural tracts primarily in the dorsal columns (posterior columns) of the spinal cord (the portion closest to the back of the body) & dorsal roots.
Name
Confusion, 70, autopsy - diagnosis?
Alzheimers Disease
This is an amyloid plaque. Look at the big, swollen black neurities! Those are filled with amyloid protein aggregates.
- Amyloid plaques are accumulation of beta amyloid between neurons. And neurofibrillary tangles are intracellular aggregates of tau protein. These are often associated with swollen neurities.
- Neuofibillary tangles also in Picks, supranuclear palsy, etc
Proximal weakness and pain- diagnosis?
Polymyositis – infiltration inflammation with muscle fiber destruction (left, H&E; right, trichrome). (not rimmed vacuoles like IBM, not perifasicular inflammation like dermatomyositis)
Other histologic features include type II atrophy, fiber type grouping. Usually presents with proximal weakness and pain.
Polymyositis is an idiopathic inflammatory myopathy that typically occurs between the ages of 40 and 50.
Symptoms: Proximal weakness and pain
CK >10x normal
Treatment: Steroids +/- steroid sparing agent
Proximal weakness -dx?
Dermatomyositis – as opposed to polymyositis, the inflammation and atrophy are largely perifascicular in dermatomyositis.
Dermatomyositis, but not polymyositis, has been associated with a higher degree of malignancy.
Other features of DM are a heliotrope rash, shaw sign and Gottron papules.
A 55 year old female presents with muscle pain and proximal weakness of several weeks duration. Her muscle biopsy is shown. Which of the following is the most likely diagnosis?
- Dysferlinopathy
- Polymyositis
- Inclusion body myositis
- Dermatomyositis
The constellation of findings is most consistent with polymyositis.
60, proximal weakness, Dx?
Inclusion Body Myositis – the hallmark of IBM is “rimmed vacuoles”, or vacuolations in the muscle fibers lined with an eosinophilic rim. Less inflammatory infiltrate.
Idiopathic inflammatory myopathy
Onset: >50 yo
Symptoms: Quadricep and deep finger flexor weakness. May be asymmetric.
CK normal to 10x normal. No treatment available.
Other conditions may give rise to rimmed vacuoles, such as chloroquine toxicity.
What is this?
Polymyositis
What do target fibers suggest in a muscle biopsy?
- Acute demyelination
- Target fibers appear as a centrally located dark staining patches on gomori’s modified trichrome and are best demonstrated by NADH-TR staining. There is a pale core with no NADH=TR activity surrounded by a dark ring and rimmed by a more normal staining peripheral zone.
- Histochemical and ultrastructural observations suggest that they are secondary to a disturbed tropic influence of the nervous system such as denervation
What is the pathological finding in muscle fibers associated with hypokalemic periodic paralysis?
•Vacuolar Dilatation of Sarcoplasmic reticulum is found in muscle biopsy of patients with hypokalemic periodic paralysi
Weak child, thin thighs, preserved calves
Duchenne Muscular Dystrophy – on the left is an H&E and the right a trichrome of Duchenne muscular dystrophy.
Rounded muscle fibers, variable fiber size, increased connective tissue, and fat.
The disease is caused by mutations in the gene for dystrophin (X-linked) which results in the absence of dystrophin form the muscle fiber surface.
What is this?
Discussion:
Myotonic dystrophy (MD) is characterized pathologically by predominance of small type I fibers and increased internal nuclei. Type I MD tends to display more numerous ring fibers and targetoid fibers than Type II MD.
type I
Name
Which glycogen storage disease affects only skeletal muscle?
Symptoms in glycogen storage diseases depend on the tissue distribution of the missing enzyme. McArdle disease, which is due to myophosphorylase deficiency, affects only skeletal muscle. Most of the other glycogen storage disease, including von Gierke disease, liver phosphorylase kinase deficiency, Forbes disease, and Pompe disease, also affect the liver.
Weakness, difficulty relaxing hand
Myotonic Dystrophy – on the left shows multiple internal nuclei characteristic of myotonic dystrophy.
This disease features more internal nuclei than any other muscle disorder.
The right longitudinal section shows that the interal nuclei within the muscle fibers also tend to line up. Note the increase in connective tissue.
Myotonic dystrophy results from a triplet repeat expansion of the myotonin gene on chromosome 19; more severe anticipation occurs with maternal inheritance
What is this
- Vasculitis:
- Discussion:
- The muscle biopsy specimen shows a necrotizing vasculitis with fibrinoid necrosis of the vessel walls, not amyloid angiopathy.
Vasculitis may be seen in amphetamine-induced vasculitis, polyarteritis nodosa, rheumatoid vasculitis, and Wegener granulomatosis, but not in polymyalgia rheumatica which is associated with temporal arteritis and usually type II fiber atrophy in the muscle biopsy, not vasculitis. Takayasu arteritis affects large blood vessels such as aortic arch, not small intramuscular vessels.
A 45 year old male presents with proximal muscle weakness that developed over the last year. His EMG shows a non-irritative proximal predominant myopathy. Muscle biopsy is shown. Use of which of the following drugs could be the cause of his symptoms?
- Statin
- Colchicine
- Prednisone
- Cocaine
Prednisolone
What is this?
Trichinosis – pictured is a cyst containing the larvae of Trichinella spiralis within muscle. Infection is initiated via ingestion of living larvae in raw or undercooked meat (usually pork) and results in eosinophilc fever and myalgias.
Myoclonus, seizures and blindness - diagnosis?
Lafora body disease
Autosomal recessive
Intractable progressive myoclonic and generalized seizures, dementia, and cortical blindness
Age: 11-18 yo at onset; Total disability in 5-8 years
Dx: Biopsy of skin, liver, muscle or brain with pathognomonic polyglucosan inclusions
Tx: Limited to treatment of seizures
Progressive confusion- autopsy - diagnosis?
•CJD
•
Spongiform degeneration is characteristic of Creutzfeldt-Jacob disease. Most cases are sporadic and occur in patients between 50 and 70 years of age. Iatrogenic transmission can occur but is rare. Startle myoclonus is commonly seen. Although patients may have elevated protein 14-3-3 levels in CSF, this is a non-specific finding which may be seen in other neurologic disorders
CJD is caused by protein particles known as prions they are innocuous proteins but become pathological when transformed into their beta sheet rich isoforms
Headache - diagnosis?
Giant cell arteritis
Sections demonstrate inflammation with giant cells centered on the internal elastic lamina of the temporal artery, characteristic of giant cell arteritis. Although primary angiitis of the CNS may have overlapping histologic features, it affects primarily leptomeningeal blood vessels and presents clinically with multifocal infarcts rather than headache or jaw claudication. Polyarteritis nodosa is characterized histologically by fibrinoid necrosis, and vessels in Moyamoya syndrome have fibrointimal proliferation. Amyloid angiopathy is characterized by Congo red-positive deposits within vessel walls
What is the histopathological finding of Moya Moya?
•Intimal Fibroplasia
•
- Moya Moya is characterised by intimal thickening in the walls of the terminal portions of the internal carotid vessels bilaterally
- Proliferating intima may contain lipid deposits.
•
Confusion - diagnosis?
Lewy body disease (large number)
Multiple systems atrophy (within glia), Parkinsons disease dementia or LBD
Intraventricular hemorrhage in the preterm infant vs term infant usually originates from which of the following structures?
- Germinal matrix (preterm infant)
- Choriod plexus is the source of intraventricular hemorrhage in the term infant
Confusion - diagnosis?
- These are senile plaques
- Dx Alzheimer’s Dementia
- Consist of – amyloid deposits surrounded by numerous astrocytic processes, neuron terminals, and swollen neurites.
- Tau protein is the main component of neurofibrillary tangles, but is not seen in senile plaques
Encephalitis then death - diagnosis?
The characteristic inclusion body of rabies (Negri body) is classically seen in large pyramidal neurons of the hippocampus and is located in the cytoplasm.
Bats, raccoons, skunks and foxes
Highest case fatality rate of any infectious disease (30-70,000 deaths/yr worldwide) - Encephalitic: hydrophobia, aerophobia, and hyperactivity
Paraylitic: Quadriparesis with sphincter involvement, may mimic GBS (but persistent fever and normal sensation except at inoculation site)
Confusion - diagnosis?
Hirano bodies are nonspecific, highly eosinophilic inclusions, located primarily in the cells of the subiculum and the CA1 region of the hippocampus.
Large numbers, suggest Alzheimer’s
Diagnosis?
Pick bodies - on a tau stain
40 progressive dementia, abnormal limb movements
Huntington’s disease – atrophy of the caudate nucleus bilaterally suggestive of HD
Triplet repeat of CAG , AD
Which chromosome???
- 4
HIV
•Human immunodeficiency virus (HIV) related cognitive change is frequently accompanied by neurologic dysfunction sometime during the course of the infection. This may be from opportunistic infections and/or primary involvement of white matter in the brain by HIV resulting in a subcortical dementia-like picture. Macrophages and multinucleate giant cells infected with the virus are seen in perivascular spaces in white matter.
- Measles
- Discussion:Subacute sclerosing panencephalitis (SSPE) is a rare and chronic form of progressive brain inflammation caused by a persistent infection with measles virus (which can be a result of a mutation of the virus itself). The condition primarily affects children and young adults.
- SSPE is caused by defective measles virus replication secondary to natural measles virus infection before the age of two. Having become rare, it may increase again with the recent decrease in vaccination rates. Intranuclear eosinophilic inclusions and demyelination are seen histologically. Pre-morten diagnosis can be made by serum or CSF virus-specific IgG.
- Gross pathology of the brain in SSPE discloses gliotic (hard brain)
- Intracellular (type A) and intracytoplasmic neuronal and glial inclusion are usually found on microscopic examination
- Adult onset leukoencephalopathy with neuraxoanl spheroids
Discussion:
Adult-onset leukoencephalopathy with neuroaxonal spheroids is a rare adult-onset leukodystrophy, often misdiagnosed as MS or small vessel disease. Symptoms typically develop starting in the early 40s. He may have a mutation in the CSF-1R gene. Although autosomal dominant there may be no family history of the disease. Symptoms are variable and can include dementia, psychiatric problems, parkinsonism, seizures, and other neurological deficits. The spheroids are the histologic hallmark.
62, cortex, rapidly progressive dementia and hallucinations, seizures, jerks. Dx?
CJD:
CJD: spongiform (multiple lacunae causing sponge like appearance) = prion disease
What pathologic abnormality correlates with severity of cognitive loss in HIV dementia? What CSF finding correlates with dementia severity? What cells does the AIDS virus infect and replicate in?
- Neuronal dendritic los
- In HIV dementia – the pathologic feature that best correlates with severity of dementia is the grade of neuronal dentritic loss.
- Number of multinucleated giant cells has no correlation with severity of dementia
- On CSF levels of p24 antigen, beta 2 microglobulin, TNF alpha and antimyelin basic protein are shown to correlate with severity of HIV dementia. CSF tryptophan, serotonin metabolites and quinolinic acid level have recently been considered as marker of dementia severity in HIV
- HIV virus infects and replicates in microglial cels – actively synthesize viral RNA and produce progeny virions. HIV can also infect oligodendrocytes and astrocytes but doesn’t replicate in these cells
HIV, low grade fever, diagnosis?
Cerebral toxoplasmosis is the most common opportunistic CNS infection in AIDS patients and occurs in 15-50% of cases
Commonly a focal mass lesion involving the basal ganglia.
characterized by microglial nodules with associated encysted bradyzoites (obligate intracellular parasite in cellular stage).
Picture on right is RITE 2014
Pyrimethamine is used to treat toxoplasmosis.
It should be distinguished from opportunistic fungal infections, which often produce granulomatous inflammation, and from CNS lymphomas, which are characterized by large lymphoid cells which typically surround blood vessels.
What is it?
Coccidiodes- endospore
Coccidioidomycosis meningitis is endemic to the southwestern United States and northwestern Mexico.
flu-like syndrome or a limited pulmonary infection.
Meningitis most typically presents with a subacute unremitting headache.
Definitive diagnosis is made by a positive CSF fungal culture but most relied upon diagnostic study is a positive CSF cocci IgG antibody in CSG, which is highly specific.
Mature fungi in tissue are endospores, such as the one pictured, which are round and have a refractile wall.
What is it?
Aspergillosis produces gray irregular necrotic masses.
The gross photograph showed hemorrhages characteristic of vasoinvasive fungi such as Aspergillus. The photomicrograph shows a silver stain, identifying multiple septate fungi with invasion of a blood vessel in the brain, characteristic of Aspergillus species. The other organisms listed would not have this typical microscopic appearance or strong predilection for angioinvasive behavior.
The brain is second only to the lung as a site of visceral involvement, and frequently manifests as hemorrhagic infarctions.
•Alpha synuclein
•
Dementia with Lewy bodies is an example of a so-called synucleinopathy and is considered to be the second most common neurodegenerative dementia syndrome in the elderly. It is characterized clinically by fluctuating cognitive function, visual hallucinations, and mild parkinsonism. Histologically, the characteristic feature is the presence of both cortical and brainstem Lewy bodies that show immunoreactivity for alpha synuclein.
- Alzheimer’s
- Discussion:
- Neuritic plaques consist of an amyloid core and dystrophic neurites, with reactive astrocytes and microglia. They are a classic finding in Alzheimer’s disease; in the commonly used CERAD grading system, neuritic plaque counts are used as histologic criteria for making the diagnosis of Alzheimer’s disease. They are not characteristic of the other diseases listed.
Which chromosome codes for the prion protein?
- Chromosome 20
- The prion protein (PrnP) gene encodes the prion protein
- Implicated in several transmissible neurodegenerative spongiform encephalopathies
- Approximatedly 15% of cases are inherited and associated with coding mutations in the PrnP gene
Which karyotype is associated with increased meningiomas
Monosomy 22
What is this?
Desmoplastic infantile gangliogliomas
Large solid and cystic tumours with dense collagen and spindled fascicular cells
Mass from the clivus, on MRI it was hypointense on T1 and hyperintense on T2 - diagnosis?
- Chordoma:
- Rare tumour that arises from the notochord. Commonly occur at the sacrococcygeal region or at the spheno-occipital region (mostly at the clivus)
- Microscopically chordomas are composed of uniform cells with small round/oval eccentric nuclei with variably sized vacuoles located in the cell cytoplasm of the so called physalipherous cells (bubble bearing cells).
•
- Subependymal giant cell astrocytoma
- Discussion:
- Subependymal giant cell astrocytomas (SEGAs) occur almost exclusively in patients with tuberous sclerosis, which is due to the mutation or loss of a tumor suppressor gene on either chromosome 9q34 (TSC1) or chromosome 16p (TSC2). Other common manifestations of this autosomal dominant syndrome include cortical tubers, subependymal glial nodules, cutaneous angiofibromas, cardiac rhabdomyomas, pulmonary lymphangioleiomyomatosis, and renal angiomyolipomas.
•
•
Conus medullaris of a 50 year old - diagnosis?
•Myxopapillary ependymoma – subtype of ependymoma that occurs almost exclusively in the conus medullaris / cauda equina region and is thought to arise from the ependymal cells of the filum terminale. Histologically, cuboidal tumor cells arranged around vascularized stromal cors. Microcystic areas can also be found
•
What tumour is this?
The photomicrographs show classic perivascular pseudorosettes characteristic of ependymoma.
What is this
Ganglioma
The image shows a typical ganglioglioma with numerous dysmorphic ganglion cells, including binucleated forms. These tumors most frequently arise in children within the temporal lobes (often with cyst with mural nodule configuration on neuroimaging studies), and often produce seizures. The abnormal ganglion cells stain with neuronal markers, not GFAP (though the glial component would be positive for this marker). Dysmorphic ganglion cells are generally not a feature of pilocytic astrocytoma, nor are they seen in the other tumors listed. Glioblastoma and medulloblastoma are both high grade malignant neoplasms, the former glial and the later primitive embryonal (small blue cell tumor). Central neurocytoma is “neurocytic” by morphology and may closely resemble oligodendroglioma.
Langerhan’s histiocytosis
Discussion:
Langerhans cell histiocytoses may be isolated (so-called eosinophilic granuloma) or multifocal. Bone lesions in the cranium are
lytic with beveled edges. Typically sellar involvement includes a thickened enhancing infundibulum and absent posterior pituitary bright spot, which was not seen in this patient. A mixed inflammatory infiltrate of macrophages, lymphocytes, plasma cells, eosinophils and Langerhans cells is seen. Langerhans cells have a large, convoluted nucleus and are CD1a immunopositive.
28 - headache and diplopia - suprastella mass
- Craniopharyngioma – an epithelial-squamous cystic tumour arising from remnants of the craniopharyngeal duct or Rathke cleft
- Basaloid epithelium and keratin nests are characteristic
Resected ring enhancing tumour from 50 year old– what is it?
Glioblastoma multiforme – astrocytic neoplasm. Necrosis with pseudopalisading and microvascular proliferation. High cellularity and marked nuclear atypia
55, headache and personality change - diagnosis?
Glioblastoma multiforme.
Less than 3 months symptoms
Frontal , variegated appareance, hemorrhage and necrosis within it. Some mass effect
Palisading or pseudopalisading – can be seen histologically
what is this?
Myxopapillary ependymoma
Most Ependymomas (85%) are benign myxopapillary ependymomas - slow growing, low - grade tumors.
Histopathology is characterized by well differentiated cuboidal / elongaged cells without atypical / low mitotic activity arranged around papillations having a myxoid connective tissue
Eosinophilic granular bodies are found in tissue preparations of which conditions?
- Low grade gliomas
- Brightly eosinophilic round bodies in hematoxylin and eosin-prepared sections.
- Immunocytochemically some EGB are positive for antibodies against ubiquitin, Bcrystallin and glial fibrillary acidic protein.
- EGB are membrane bound round bodies of different diameters
- Generally identified in low grade gliomas
This is taken from an intraventricular tumour from a 19 year old. What is the dx.
Ependymoma. Ependymomas are composed of small cells with regular, round nuclei. Tumor cells typically form perivascular “pseudorosettes” in which cells are arranged radially around vessels with a clear region consisting of thin ependymal processes directed towards the vessel wall.
- Headaches and bitemporal hemianopia. Surgically resected tumor which is cystic with the cystic lesions containing yellow fluid and calcified areas- diagnosis?
- Craniopharyngioma – benign tumor commonly located in the suprasellar region
- Calcifications and uni-multiloculated cysts containing yellow fluid
30 yr old right temporal mass
Oligodendryoma
Fried egg appearance is characteristic – pericellular halo is a fixation artifact – but very helpful to identify oligodendrocytes.
What is this tumour?
low grade oligodendroglioma; the calcifications and “fried-egg cells” are characteristic of oligodendroglioma.
present in patients in their 30s or 40s.
Due to the high tendency of these tumors to invade the overlying cortex, seizures (often of one to five years duration) are one of the most frequent clinical presentations.
Pineal tumour taken from a 19 yr old. What is it?
Germoma. Mostly located in the pineal region or suprasellar region. Composed of neoplastic cells that have abundant clear cytoplasm (rich in glycogen) and are arranged in nests. Other cell populations generally found in germinomas are composed of small reactive T lymphocytes.
Discussion:
The microscopic findings together with immunohistochemistry is characteristic of germinoma. None of the listed alternate answers would show positivity for PLAP and CD117. Pituicytoma and granular cell tumor would both be expected to be positive for S100, the former often with positivity for GFAP also. Craniopharyngiomas should show cytokeratin staining, and look microscopically quite different from a germinoma. Pituitary adenoma may be negative for all pituitary hormone stains, but most
typically will at least show some positivity for chromogranin.