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Virology Flashcards

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1
Q

Viral genetics: Reassortment

A

When viruses with segmented genomes (e.g influenza virus) exchange genetic material
E.g. H1N1 influenza A pandemic emerged via complex viral Reassortment of a gene from human, swine and avian viruses. Has the potential to cause antigenic shift

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2
Q

Viral genetics: Complementation

A

When 1 of 2 viruses that infect the cell has a mutation that results in a nonfunctional protein, the nonmutated virus “complements” the mutated one by making a functional protein that serves both viruses.
E.g. HepD virus requires the presence of replicating HepB virus to supply HBsAg, the envelope protein for HDV

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3
Q

Viral genetics: Phenotypic mixing

A

Occurs with simultaneous infection of a cell with 2 viruses. Genome of virus A can be partially or completely coated (forming pseudovirion)with the surface proteins of virus B. Type B protein coat determines the tropism (infectivity) of the hybrid virus. However, the progeny form this infection have a type A coat that is encoded by its type A genetic material

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4
Q

Live attenuated vaccines

A

Induce a humoral and cell-mediated immunity but have reverted to virulence on rare occasions.
Live attenuated: Smallpox, yellow fever, rotavirus, chickenpox, Sabin polio virus, MMR, Influenza (intranasal) –> Live! One night only! See small yellow rotating chickens get vaccinated with Sabin and MMR! It’s INcredible!
No booster needed.
Dangerous to give live vaccines to immunocompromised patients. Close contact may be can instead with live vaccines (except polio or influenza)

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5
Q

Killed viral vaccines

A

Rabies, influenza (injected), Salk Polio, and HAV vaccines
Killed/inactivated vaccines only humoral immunity but are stable
SalK = Killed; RIP Always

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6
Q

Subunit vaccines

A

HBV (Ag = HBsAg), HPV (types 6,11,16,18)

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7
Q

DNA viral genomes

A

All DNA viruses except the parvoviridae are dsDNA
All are linear except papilloma-, polyoma- and hepadaviruses (circular)
All are dsDNA (like our cells) except part-of-a-virus (parvovirus) is ssDNA
Replicated in the nucleus (except poxvirus)

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8
Q

RNA viral genomes

A

All RNA viruses except Reoviridae are ssRNA
Positive strand RNA viruses: I went to a retro (retrovirus) toga (togavirus) party, where I drank flavored (flavivirus) Corona (coronavirus) and ate hippie (Hepevirus) California (Calicivirus) pickles (picornavirus)
Replicated in the cytoplasm (except influenza virus and retroviruses)

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9
Q

Naked viral genome infectivity

A

Purified nucleic acids of most dsDNA (except poxviruses and HBV) and + strand ssRNA (mRNA) viruses are infectious.
Naked nucleic acids of - strand ssRNA and dsRNA viruses are not infectious but require polymerase a contained in the complete virion.

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10
Q

Viral envelopes

A

Naked (non-enveloped) viruses include Papillomarvirus, Adenovirus, Parvovirus, Polyomavirus, Calicivirus, Picornavirus, Reovirus and Hepevirus
Give PAPP smears and CPR to a naked hippie (Hepevirus)
Generally enveloped viruses acquire their envelopes from plasma membrane when they exit the cell. Exceptions include herpesviruses, which acquire envelopes from the nuclear membrane

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11
Q

DNA virus characteristics

A 
Are HHAPPPPy viruses (*Hepadna, Herpes, Adeno, Pox, Parvo, Papilloma, Polyoma*)
Are double stranded (except Parvo = ssDNA)
Have linear genomes (except papilloma and polyoma - circular, supercoiled) and Hepadna (circular, incomplete)
Are icosahedral (except pox - complex)
Replication in the nucleus (except pox - carries own DNA dependent RNA polymerase)
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12
Q

DNA virus: Herpesviruses

A

Envelope: yes
DNA structure: DS & linear
Medical importance: HSV-1 & HSV-2

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13
Q

DNA virus: Poxvirus

A

Envelope: yes
DNA structure: DS & Linear (largest DNA virus)
Medical: smallpox eradicated worldwide by use of the live-attenuated vaccine
-cowpox (“milkmaid blisters”)
Molluscum contagiosum - flesh colored papule with central umbilication

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14
Q

DNA virus: Hepadnavirus

A

Envelope: yes
DNA structure: Partially DS & circular
Medical: HBV - acute or chronic hepatitis, not a retrovirus but has reverse transcriptase

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15
Q

DNA virus: Adenovirus

A

Envelope: no
DNA structure: DS & linear
Medical: febrile pharyngitis (sore throat), acute hemorrhagic cystitis, pneumonia, conjunctivitis

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16
Q

DNA virus: Papillomavirus

A

Envelope: no
DNA structure: DS & circular
Medical: HPV-warts (serotypes 1,2,6,11), CIN, Cervical cancer (16,18 most commonly)

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17
Q

DNA virus: Polyomavirus

A

Envelope: no
DNA structure: DS & circular
Medical: JC virus - progressive mutilfocal leukoencephalopathy (PML) in HIV; BK virus - transplant pts commonly targets kidney
JC: Junky Cerebrum; BK: Bad Kidney

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18
Q

DNA virus: Parvovirus

A

Envelope: no
DNA structure: SS & linear (smallest DNA virus)
Medical: B19 virus - aplastic crisis in sickle cell disease, “slapped cheek” rash in children (erythema infectiosum/fifths disease)
RBC destruction in fetus leads to hydrops fetalis and death, in adults leads to pure RBC aplasia and rheumatoid arthritis-like symptoms

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19
Q

Viral genetics: Recombination

A

Exchange of genes between 2 chromosomes by crossing over within regions of significant base sequence homology

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20
Q

Herpes simplex virus-1

A

Enveloped, DS and linear
Transmission: respiratory secretions, saliva
Clinical: gingivostomatitis, keratoconjuntivitis, herpes labialis, hermetic whitlow on finger, termporal lobe encephalitis
Most common cause of sporadic encephalitis –> can present as altered mental status, seizures, and/or aphasia

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21
Q

Herpes simplex virus-2

A

Enveloped, DNA, linear
Transmission: sexual contact, perinatal
Clinical: Herpes genitalis, neonatal herpes
Latent in sacral ganglia. Viral meningitis more common with HSV-2 than with HSV-1

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22
Q

Varicella-Zoster Virus (HHV-3)

A

Enveloped, DNA, linear
Transmission: respiratory secretions
Clinical: varicella-zoster (chickenpox, shingles), encephalitis, pneumonia; most common complication of shingles is post-herpetic neuralgia
Latent in dorsal root or trigeminal ganglia

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23
Q

Epstein-Barr virus (HHV-4)

A

Enveloped, DNA, linear
Transmission: respiratory secretions, saliva (kissing disease - common in teens/young adults)
Clinical: mononucleosis (fever, hepatosplenomegaly, pharyngitis, lymphadenopathy esp posterior cervical LNs); avoid contact sports until resolution due to risk of splenic rupture; associated with lymphomas (eg endemic Burkitt lymphoma), nasopharyngeal carcinoma
Infects BCs through CD21.
Atypical lymphocytes on peripheral blood smear - not infected BCs but reactive CTCs
+ monospot test - heterophile Ab detected by agglutination of sheep or horse RBCs

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24
Q

Cytomegalovirus (HHV-5)

A

Enveloped, DNA, linear
Transmission: congenital, transfusion, sexual contact, saliva, urine, transplant
Clinical: mononucleosis in immunocompotent pts (monospot -), infection in immunocompromised pts (esp pneumonia in transplant pts), AIDS retinitis (sightomegalovirus), hemorrhage, cotton-wool exudates, vision loss; Congenital CMV
Infected cells have characteristic “owl eye” inclusions. Latent in mononuclear cells

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25
Q

Human herpes virus 6&7

A

Enveloped, DNA, linear
Transmission: saliva
Clinical: Roseola infantum (exanthem subitum): high fevers for several days that can cause seizures, followed by diffuse macular rash
HHV-7-less common cause of roseola

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26
Q

Human herpesvirus 8

A

Enveloped, DNA, linear
Transmission: sexual contact
Clinical: Kaposi sarcoma (neoplasm of endothelial cells). Seen in HIV/AIDS and transplant pts. Dark/violaceous plaques or nodules representing vascular proliferation so
Can also affect GI & lungs

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27
Q

HSV identification

A

Viral culture for skin/genitalia
CSF PCR for herpes encephalitis
Tzanck test (Tzank heavens I do not have herpes) - a smear of an opened skin vesicle to detect multinucleated giant cells commonly seen in HSV-1,2 & VZV infection
Intramuscular inclusions also seen in 1,2&VZV

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28
Q

Receptor used by CMV

A

Integrity (heparin sulfate)

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29
Q

Receptor used by EBV

A

CD21

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30
Q

Receptor used by HIV

A

CD4, CXCR4, CCR5

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31
Q

Receptor used by Rabies

A

Nicotinic AChR

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32
Q

Receptor used by Rhinovirus

A

ICAM-1

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33
Q

RNA viruses: Reovirus

A

Envelope: No
RNA structure: DS linear, 10-12 segments
Capsid: Icosahedral (double)
Medical: Coltivirus (Colorado tick fever); rotavirus (number one cause of fatal diarrhea in children)

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34
Q

RNA viruses: Picornavirus

A

Envelope: No
RNA structure: SS + linear
Capsid: Icosahedral
Medical: (PERCH) - Poliovirus (polio-Salk/Sabin vaccines-IPV/OPV); Echovirus (aseptic meningitis); Rhinovirus (common cold); Coxsackievirus (aseptic meningitis; herpangina-mouth blisters, fever; hand foot and mouth disease; myocarditis, pericarditis); HAV (acute viral hepatitis)

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35
Q

RNA viruses: Hepevirus

A

Envelope: No
RNA structure: SS + linear
Capsid: Icosahedral
Medical: HEV

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36
Q

RNA viruses: Caliciviruses

A

Envelope: No
RNA structure: SS + linear
Capsid: Iscosahedral
Medical: Norovirus (viral gastroenteritis)

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37
Q

RNA viruses: flavivirus

A

Envelope: Yes
RNA structure: SS + linear
Capsid: Icosahedral
Medical: HCV; yellow fever, Dengue, St. Louis encephalitis, West Nile virus

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38
Q

RNA viruses: Toga virus

A

Envelope: Yes
RNA structure: SS + linear
Capsid: Icosahedral
Medical: Rubella, Eastern equine encephalitis, Western equine encephalitis

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39
Q

RNA viruses: Retrovirus

A

Envelope: yes
RNA structure: SS + linear, 2 copies
Capsid: Icosahedral (HTLV), complex and conical (HIV)
Medical: have reverse transcriptase, HTLV (TC leukemia); HIV/AIDS

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40
Q

RNA viruses: Coronavirus

A

Envelope: yes
RNA structure: SS + linear
Capsid: helical
Medical: Common cold, SARS, MERS

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41
Q

RNA viruses: Orthomyxoviruses

A

Envelope: yes
RNA structure: SS - linear, 8 segments
Capsid: Helical
Medical: Influenza virus

42
Q

RNA viruses: paramyxovirus

A

Envelope: yes
RNA structure:
Capsid:
Medical: Parainfluenza (croup), RSV (brnochiolitis in babies with Ribavirin as treatment); measles, mumps

43
Q

RNA viruses: Rhabdoviruses

A

Envelope: yes
RNA structure: SS - linear
Capsid: helical
Medical: Rabies

44
Q

RNA viruses: Filoviruses

A

Envelope: yes
RNA structure: SS - linear
Capsid: Helical
Medical: Ebola/Marburg hemorrhagic fever - often fatal/

45
Q

RNA viruses: Arenaviruses

A

Envelope: yes
RNA structure: SS + or - circular, 2 segments
Capsid: helical
Medical: LCMV (lymphocytic choriomeningitis virus); Lassa fever encephalitis (spread by rodents)

46
Q

RNA viruses: Bunyaviruses

A

Envelope: yes
RNA structure: helical
Capsid: SS - circular, segments
Medical: California encephalitis; sandfly/Rift Valley fevers; Crimean-Congo hemorrhagic fever; Hantavirus (hemorrhagic fever, pneumonia)

47
Q

RNA viruses: Delta virus

A

Envelope: yes
RNA structure: SS - circular
Capsid: uncertain
Medical: HDV is a “defective” virus that requires the presence of HBV to replicate

48
Q

Negative stranded viruses

A 
Must transcribe - strand to +
Virion brings its own RNA-dependent DNA polymerase
*Always Bring Polymerase Or Fail Replication*
Arenaviruses
Bunyaviruses
Paramyxoviruses
Orthomyxoviruses 
Filoviruses
Rhabdoviruses
49
Q

Segmented viruses

A 
All are RNA viruses
*BOAR*
Bunyaviruses
Orthomyxoviruses (influenza)
Arenaviruses 
Reoviruses
50
Q

Picornavirus

A

Includes: PERCH
Poliovirus, Echovirus, Rhinovirus, Coxsackievirus, HAV
RNA is translated into 1 large polypeptide that is cleaved by proteases into functional viral proteins.
Can cause aseptic (viral) meningitis (except rhinovirus and HAV)
All are enteroviruses (fecal-oral) except rhinovirus

51
Q

Rhinovirus

A

A picornavirus
Nonenveloped RNA
Cause of the common cold with over 100 serologic types
Acid-labile so destroyed by stomach acid; therefore does not interfere with GI tract

52
Q

Yellow Fever Virus

A

A flavivirus (also an arbovirus) transmitted by Ades mosquitos
Virus has monkey or human reservoir
Symptoms: high fever, black vomitus, jaundice
May see councilman bodies (eosinophilic apoptotic globules) on liver biopsy

53
Q

Rotavirus

A

Most important global cause of infantile gastroenteritis
Segmented dsRNA virus (reovirus)
Major cause of acute diarrhea in the USA during winter, esp in day care centers, kindergartens
Villus destruction with atrophy leads to decreased absorption of Na+ and loss of K+

54
Q

Influenza virus

A

Orthomyxoviruses. Enveloped - ssRNA viruses with 8 segment genome
Contain hemagglutinin (promotes viral entry) and neuraminidase (promotes progeny virion release) Ag
Pts at risk for fatal bacterial superinfection, most commonly S.aureus, S.pneumoniae, H.influenzae

55
Q

Influenza vaccine

A

Reformulated vaccine contains viral strains most likely to appear during the flu season due to the virus’ rapid genetic change
Killed viral vaccine is the most commonly used
Live attenuated vaccine contains temperature-sensitive mutant the replicates in the nose but not the lung: administered intranasally

56
Q

Genetic/Antigentic shift

A

Causes pandemics
Reassortment of viral genome segments, such as when segments of human flu A virus reassort with swine flu A virus
Sudden Shift is more deadly than a graDual Drift

57
Q

Genetic/Antigenic drift

A

Causes epidemics

Minor (antigenic drift) changes base on random mutation in hemagglutinin or neuraminidase genes

58
Q

Rubella virus

A

Togaviruse
Causes rubella (German measles): fever, postauricular and other lymphadenopathy, arthralgias, and fine confluent Rays that starts on face and spreads centrifugally to involve trunk and extremities. Causes mild disease in children but serious congenital disease (a ToRCHeS infection)
Congenital rubella findings include “blueberry muffin” appearance due to dermal extra medullary hematopoiesis

59
Q

Paramyxovirus

A

Disease in children: parainfluenza (Croup: seal-like barking cough), mumps and measles, RSV (can lead to URI –> brnochiolitis, pneumonia) in infants
All contain surface F (fusion) protein, which causes respiratory epithelial cells to fuse and from multinucleated cells.
Palivizumab (monoclonal Ab against F protein) prevents pneumonia by RSV infection in premature infants

60
Q

Croup (acute laryngotracheobronchitis)

A

Cause by parainfluenza viruses (paramyxovirus)
Results in seal-like barking cough and inspiratory stridor
Narrowing of upper trachea and subglottis leads to characteristic steeple sign on XR
Severe croup can result in pulsus paradoxus secondary to upper airway obstruction

61
Q

Measles (rubeola) virus

A

Paramyxovirus
Presentation: prodromal fever with cough, coryza and conjunctivitis then eventually Koplik spots (bright red spots with blue-white center on Buccaneers mucosa) followed 1-2 days later by a maculopapular rash that starts at the head/neck and spreads downward
Lymphadenitis with Warthin-Finkeldey giant cells (fused lymphocytes) in a background of paracortical hyperplasia
SSPE (subacute sclerosing panencephalitis - occurring years later), encephalitis and giant cell pneumonia (rarely - immunosuppressed) are possible sequelae

62
Q

Mumps virus

A

Paramyxovirus uncommon due to effectiveness of MMR vaccine
Symptoms: parotitis, Orchitis (inflammation of testes), aseptic meningitis, pancreatitis
Can cause sterility esp after puberty

63
Q

Rabies virus

A

Bullet shaped virus
Negri bodies (cytoplasmic inclusions) commonly found in Purkinje cells of cerebellum and hippocampal neurons
Rabies has a long incubation period (weeks to months) before symptom onset
Post-exposure prophylaxis is wound cleaning plus immunization with killed vaccine and rabies immunoglobulin (passive-active immunity)
Travels CNS by migrating retrograde fashion up nerve axons after binding to ACh receptors
Progression of disease: fever, malaise –> agitation, photophobia, hydrophobia, hyper salivation –> paralysis, coma –> death
Infections more commonly from bat, raccoon, and skunk bites than from dog bites in USA
Aerosol transmission also possible (bat caves)

64
Q

Ebola virus

A

A Filovirus that targets endothelial cells, phagocytes, hepatocytes
Following an incubation period of up to 21 days, presents with abrupt onset of flu-like symptoms, diarrhea/vomiting, high fever, myalgia
Can progress to DIC, diffuse hemorrhage, shock
Diagnosed with RT-PCR within 48 hours of symptom onset
High mortality rate
Transmission: direct contact with body fluids, fomites (including dead bodies), infected bats or primates, high incidence of nosocomial infection
Supportive care, no definitive treatment; strict isolation of infected individuals and barrier practices for health care workers are key to preventing transmission

65
Q

Hepatitis virus

A

Signs and symptoms of all: fever, jaundice, increased ALT/AST; Naked viruses (A&E) lack an envelope and are not destroyed by the gut (vowels hit the bowels)
HBV DNA polymerase has DNA and RNA dependent activities. Upon entry into nucleus the polymerase completes the partial dsDNA. Host RNA polymerase then reverse transcribes mRNA from viral DNA to make viral proteins. The DNA polymerase then reverse transcribes viral RNA to DNA, which is genome of the progeny virus
HCV lacks 3’-5’ exonuclease activity –> variation in antigenic structures of HCV envelope proteins. Host Ab production lags behind production of new mutant strains of HCV

66
Q

HAV

A

Family: RNA picornavirus
Transmission: fecal-oral (shellfish, travelers, day care)
Incubation: short (weeks)
Clinical Course: Asymptomatic (usually) or Acute
Prognosis: Good
HCC Risk: No
Liver biopsy: Heptocyte swelling, monocytes, infiltration, councilman bodies
Notes: No carrier state (Alone)

67
Q

HBV

A

Family: DNA hepadnavirus
Transmission: patenteral (Blood), Sexual (Baby-making), perinatal (Birthing)
Incubation: Long (months)
Clinical Course: Initially like serum sickness (fever, arthralgias, rash) may progress to carcinoma
Prognosis: most adults have full resolution , minority have chronic infection
HCC Risk: yes
Liver biopsy: granular eosinophilic “ground glass” appearance; CTC mediated damage
Notes: Carrier state common

68
Q

HCV

A

Family: RNA flavivirus
Transmission: primarily blood (IVDU, post-transfusion)
Incubation: long
Clinical Course: may progress to Cirrhosis or Carcinoma
Prognosis: majority develop stable, Chronic hepatitis C
HCC Risk: yes
Liver biopsy: Lymphoid aggregates with focal areas of macrovesciular steatosis
Notes: Carrier state common

69
Q

HDV

A

Family: RNA delta virus
Transmission: parenteral, sexual, perinatal
Incubation: superinfection - HDV after HBV = short; coinfection (HDV with HBV = long
Clinical Course: Similar to HBV (initially like serum sickness; may progress to carcinoma)
Prognosis: superinfection –> worse prognosis
HCC Risk: Yes
Liver biopsy: similar to HBV (granular eosinophilic)
Notes: Defective virus, Depends on HBV

70
Q

HEV

A

Family: RNA Hepevirus
Transmission: Fecal-oral (esp waterborne)
Incubation: Short
Clinical Course: Fulminant hepatitis in Expectant (pregnant) women
Prognosis: High mortality rate in pregnant women
HCC Risk: No
Liver biopsy: patchy necrosis
Notes: Enteric, Epidemic, no carrier state

71
Q

Hepatitis serological markers: Anti-HAV (IgM)

A

IgM Ab to HAV

Best test to detect acute hepatitis A

72
Q

Hepatitis serological markers: Anti-HAV (IgG)

A

IgG Ab indicates prior HAV infection and/or prior vaccination
Protects against reinfection

73
Q

Hepatitis serological markers: HBsAg

A

Ag found on surface HBV

Indicates HBV infection

74
Q

Hepatitis serological markers: Anti-HBs

A

Ab to HBsAg

Indicates immunity to hepatitis B

75
Q

Hepatitis serological markers: HBcAg

A

Ag associated with core of HBV

76
Q

Hepatitis serological markers: Anti-HBc

A

Antibody to HBcAg;
IgM = recurrent infection (may be the sole + marker during window period)
IgG = prior exposure or chronic infection

77
Q

Hepatitis serological markers: HBeAg

A

Secreted by infected hepatocytes into circulation
Not a part of mature HBV virion
Indicates active viral replication and therefore high transmissibility

78
Q

Hepatitis serological markers: Anti-HBe

A

Ab to HBeAg

Indicates low transmissibility

79
Q

HIV

A

Diploid genome (2 molecules of RNA)
3 structural genes
-env (gp120 & gp41): formed from cleavage of gp160 to form envelope proteins
–gp120 attaches to host CD4+ TCs
–gp41 promotes fusion and entry
-gag (p24 & p17): capsid and matrix protein
-pol: reverse transcriptase (synthesizes dsDNA from genomic RNA –> dsDNA then integrates into host genome), Aspartate protease, integrase
Virus binds CD4+ as well as core captor, either CCR5 on MPs (early infection) or CXCR4 (late infection) on TCs
Homozygous CCR5 mutation = immunity
Heterozygous CCR5 mutation = slower course

80
Q

HIV diagnosis

A

Presumptive diagnosis made with ELISA (sensitive, high false + rate and low threshold)
+ results then confirmed with Western Blot assay (specific, low false positive and high threshold, rule in test)
Look for Ab to viral proteins; these tests are often falsely - in the first 1-2 months of HIV infection and falsely positive initially when babies are born to mothers (anti-gp120 crosses placenta)

81
Q

HIV/AIDS diagnosis & viral load

A

Viral load tests determine the amount of viral RNA in the plasma
High viral load is associated with poor prognosis
Also used to monitor effect of drug therapy
AIDS diagnosis:

82
Q

Time course of untreated HIV infection

A

Four stages of untreated infection

  1. Flu-like (acute)
  2. Feeling fine (latent) - replicates in LNs
  3. Falling count (immunocompromised
83
Q

Common diseases of HIV+ adults

A

as CD4+ cell count decreases, risk of reactivation of past infections (TB, HSV, shingles), dissemination of bacterial infections and fungal infections (coccidiodomycosis) and non-Hodgkin lymphoma increases

84
Q

CD4+ count

A

Oral thrush

Scrapable white plaque, pseudohyphae on microscopy

85
Q

CD4+ count

A

Oral hairy leukoplakia

Unscrapable white plaque on lateral tongue

86
Q

CD4+ count

A

Bacillary angomatosis

Biopsy with neutrophilic inflammation

87
Q

CD4+ count

A

Kaposi sarcoma

Biopsy with lymphocytic inflammation

88
Q

CD4+ count

A

Chronic, watery diarrhea

Acid-fast oocytes in stool

89
Q

CD4+ count

A

Squamous cell carcinoma, commonly of anus (men who have sex with men) or cervix (women)

90
Q

CD4+ count

A

Dementia

91
Q

CD4+ count

A

Progressive multifocal leukoencephalopathy

Nonenhancing areas of demyelination on MRI

92
Q

CD4+ count

A

Pneumocystis pneumonia

Ground glass opacities on CXR

93
Q

CD4+ count

A

Hemoptysis, pleuritic pain

Cavitation or infiltrates on CXR

94
Q

CD4+ count

A

Meningitis

Encapsulated yeast on India Ink stain or capsular Ag +

95
Q

CD4+ count

A

Esophagitis

White plaques on endoscopy, yeast and pseudohyphae on biopsy

96
Q

CD4+ count

A

Retinitis, esophagitis, colitis, pneumonitis, encephalitis
Linear ulcers on endoscopy, cotton wool spots on fundscoptic exam
Biopsy reveals cells with intranuclear (owl eye) inclusion bodies

97
Q

CD4+ count

A

B-cell lymphoma (eg. Non-Hodgkin lymphoma, CNS lymphoma)

CNS - ring enhancing, may be solitary (vs. toxoplasma)

98
Q

CD4+ count

A

Fever, weight loss, fatigue, cough, dyspnea, nausea, vomiting, diarrhea
Oval yeast cells within MPs

99
Q

CD4+ count

A

Nonspecific systemic symptoms (fever, night sweats, weight loss) or focal lymphadenitis

100
Q

CD4+ count

A

Brain abscesses

Multiple ring-enhancing lesions on MRI

101
Q

Prions

A

Prion disease are caused by the conversion of a normal (predominantly alpha-helical) protein termed prion protein (PrP) to a beta pleated form, which is transmissible via CNA-related tissue (iatrogenic CJD) or food contaminated by BSE-infected animal products (variant CJD).
Resists protease degradation and facilitates the conversion of even more protein into the beta form. Resistant to standard sterilizing procedures, including standard autoclave.
Accumulation of beta sheets results in spongiform encephalopathy and dementia, ataxia and death

102
Q

Prion Diseases

A

Creutzfeldt-Jakob disease - rapidly progressive dementia, typically sporadic (some familial forms)
Bovine spongiform encephalopathy (BSE) - aka mad cow disease
Kuru - acquired from prion disease noted in tribal populations practicing human cannibalism

Microbiology (8 decks)

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