FA - Micro - Virology Flashcards Preview

Microbiology > FA - Micro - Virology > Flashcards

Flashcards in FA - Micro - Virology Deck (246):
0

Viral genetics - Recombination?

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

1

Viral genetics - Reassortment?

When viruses with segmented genomes (e.g., influenza virus) exchange segments.
==> 2009 novel H1N1 influenza A pandemic ==> Complex reassortment of genes from HUMAN + SWINE + AVIAN viruses.
==> POTENTIAL FOR ANTIGENIC SHIFT.

2

Viral genetics - complementation?

When 1 OF 2 viruses that infect the cell has a mutation that results in a NON FUNCTIONAL PROTEIN.
==> The NON MUTATED virus "complements" the mutated one by making a functional protein that serves BOTH viruses.

3

Viral genetics - phenotypic mixing?

1. Occurs with SIMULTANEOUS infection of a cell with 2 VIRUSES.
2. Genome of virus A can be partially or completely coated (forming pseudovirion) with the surface proteins of virus B.
3. Type B protein coat determines the tropism (infectivity) of the hybrid virus.
4. The progeny from this infection have a type A coat that is encoded by its type A genetic material.

4

Live attenuated vaccines - mechanism?

Induce humoral AND cell-mediated immunity - have reverted to virulence on RARE occasions.

5

Killed/inactivate vaccines - mechanism?

Induce ONLY HUMORAL immunity but are stable.

6

Live attenuated vaccines - mention some?

1. Smallpox
2. Yellow fever
3. Chickenpox (VZV)
4. Sabin polio virus
5. MMR
6. Influenza (Intranasal)

7

Live attenuated vaccines - need a booster?

NO BOOSTER.

8

Killed vaccines - mention some?

1. Rabies
2. Influenza (injected)
3. Salk Polio
4. HAV vaccines

9

Recombinant vaccines - 2 examples?

1. HBV (antigen= HBsAg)
2. HPV (types 6, 11, 16, 18).

10

All DNA viruses are ds, EXCEPT?

Parvo (Latin for small)

11

All DNA viruses are linear, EXCEPT?

1. Papilloma
2. Polyoma
3. Hepadna
(circular)

12

All RNA viruses are ss, EXCEPT?

Reo (Repeato-virus ==> ds).

13

Positive-stranded RNA viruses?

1. Retro
2. Toga
3. Flavi
4. Calici
5. Picorna
6. Corona
7. Hepevirus

14

Naked viral genome infectivity?

Purified nucleic acids of most dsDNA (EXCEPT pox and HBV) and +strand ssRNA --> INFECTIOUS.

15

NON infectious naked nucleic acids?

Naked nucleic acids of (-)strand ssRNA and dsRNA viruses are NOT infectious --> Require polymerases contained in the complete virion.

16

DNA viruses - viral replication?

ALL IN THE NUCLEUS (except POX).

17

RNA viruses - viral replication?

ALL in the CYTOPLASM - except INFLUENZA and RETRO.

18

Viral envelopes - Naked?

DNA ==>
1. Papilloma
2. Polyoma
3. Adeno
4. Parvo
RNA ==>
5. Calici
6. Picorna
7. Reovirus
8. Herpes

19

Generally, how do enveloped viruses acquire their envelopes?

From plasma membrane when they exit the from cell.
EXCEPT HERPESVIRUSES ==> Acquire envelopes from nuclear membrane.

20

General rule - ALL DNA viruses are?

1. HHAPPPPy --> Hepadna, Herpes, Adeno, Pox, Parvo, Polyoma, Papilloma.
2. DOUBLE-STRANDED
3. LINEAR GENOMES
4. ICOSAHEDRAL --> except pox (complex)
5. NUCLEUS for replica --> except pox (carries OWN DNA-dependent RNA poly).

21

Herpesviruses - envelope?

Yes.

22

Herpesviruses - DNA structure?

DS and linear.

23

HSV-1 - disease?

1. Gingivostomatitis.
2. Keratoconjunctivitis.
3. Herpes labialis.
4. Herpetic whitlow on finger.
5. Temporal lobe encephalitis.

24

HSV-2 - disease?

1. Herpes genitalis.
2. Neonatal herpes.

25

VZV (HHV-3) - disease?

1. Chickenpox.
2. Shingles.
3. Encephalitis.
4. Pneumonia.

26

VZV - vaccine?

Available

27

EBV (HHV-4) - disease?

1. Mono
2. ENDEMIC Burkitt
3. HL.
4. Nasopharyngeal carcinoma.

28

CMV (HHV-5) - disease?

1. Mononucleosis (Monospot NEGATIVE) in IMMUNOCOMPETENT patients.
2. PNEUMONIA in transplant patients.
3. AIDS RETINITIS ("sightomegalovirus") ==> Hemorrhage + Cotton-wool exudates + Vision loss.
4. CONGENITAL CMV.

29

HHV-6 - disease?

Roseola - exanthem subitum ==> HIGH FEVER for several days that can cause SEIZURES, followed by diffuse macular rash.

30

HHV-7 - disease?

Less common cause of roseola.

31

HHV-8 - disease?

Kaposi ==> Neoplasm of ENDOTHELIAL cells.
1. In HIV/AIDS patients.
2. In transplant patients.

32

Hepadna - envelope?

YES

33

Hepadna - DNA structure?

Partially ds and circular.

34

Hepadna - disease?

HBV:
Acute/chronic hep.
==> NOT A RETROVIRUS, BUT HAS REVERSE TRANSCRIPTASE.

35

HBV - vaccine?

Available - contains HBV surface antigen.

36

HBV - reverse transcriptase?

YES, even if it's not a retrovirus.

37

Adenovirus - envelope?

No

38

Adeno - DNA structure?

DS and linear.

39

Adeno - disease?

1. Febrile pharyngitis - sore throat.
2. Acute hemorrhagic cystitis.
3. Pneumonia
4. Conjunctivitis - "pink eye".

40

Parvo - envelope?

NO

41

Parvo - DNA structure?

ss and linear (-) --> smallest DNA virus.

42

Parvo - disease?

B19:
1. Aplastic crises in SCA.
2. "Slapped cheeks" in children - erythema infectiosum (5th disease).
3. RBC destruction in fetus --> hydrops fetalis and death.
4. PURE RED CELL APLASIA + RA-like symptoms in adults.

43

Polyomavirus - envelope?

NO

44

Polyoma - DNA structure?

ds and circular.

45

Polyoma - name 2 viruses?

JC, BK

46

JC virus - disease?

Progressive multifocal leukoencephalopathy in HIV.

47

BK virus - disease?

Transplant patients, commonly targets KIDNEY. (BK for Bad Kidney).

48

Pox - envelope?

YES

49

Pox - DNA structure?

DS and linear - largest DNA virus.

50

Pox - disease?

1. Smallpox - ERADICATED world wide by use of LIVE-ATTENUATED vaccine.
2. Cowpox ("milkmaid blisters")
3. MOLLUSCUM CONTAGIOSUM - Flesh-colored dome lesions with central umbilication.

51

HSV-1 - Diseases?

1. Gingivostomatitis
2. Keratoconjunctivitis
3. Temporal lobe encephalitis (MCC of sporadic encephalitis in the US)
4. Herpes labialis
5. Herpetic whitlow on finger.

52

HSV-1 - Latent where?

In the trigeminal ganglia.

53

HSV-1 - transmission?

1. Respiratory secretions
2. Saliva

54

HSV-2 - disease?

1. Herpes genitalis
2. Neonatal herpes
==> Viral MENINGITIS is more common with HSV-2 than with HSV-1.

55

HSV-2 - Latent where?

In sacral ganglia.

56

HSV-2 - Transmission?

1. Sexually
2. Perinatally

57

VZV - Diseases?

1. Varicella-zoster (chickenpox, shingles).
2. Encephalitis
3. Pneumonia
==> MC complication of shingles is POST-HERPETIC NEURALGIA.

58

VZV - Latent where?

Dorsal root or trigeminal ganglia.

59

VZV - MC complication?

Post herpetic neuralgia.

60

VZV - Transmission?

Respiratory secretions.

61

EBV - disease?

Mononucleosis

62

Mono - Features?

1. Fever
2. HSM
3. Pharyngitis
4. Lymphadenopathy --> especially POSTERIOR CERVICAL nodes.

63

EBV - transmission?

1. Respiratory secretions
2. Saliva

64

EBV - Mechanism?

Infects B cells THROUGH CD21.
==> Atypical lymphocytes seen on peripheral blood smear infected B cells BUT rather REACTIVE CYTOTOXIC T CELLS.

65

EBV - Monospot?

Heterophile antibodies detected by agglutination of sheep or horse RBCs.

66

EBV - associations?

1. Hodgkin
2. Endemic Burkitt
3. Nasopharyngeal carcinoma

67

CMV - Diseases?

1. Congenital infection
2. Mononucleosis (Monospot (-))
3. Pneumonia
4. Retinitis

68

CMV - special feature?

Infected cells have characteristic "owl's eye" inclusions.

69

CMV - Latent where?

Mononuclear cells.

70

CMV - Transmission?

1. Congenitally
2. By transfusion
3. Sexually
4. Saliva
5. Urine
6. Transplant

71

HHV-6 - disease?

ROSEOLA --> High fevers for several days that can cause seizures, followed by a diffuse macular rash.

72

HHV-6 transmission?

By saliva.

73

HHV-8 disease?

1. Kaposi sarcoma - neoplasm of endothelial cells.
2. Dark/violaceous flat and nodular skin lesions representing endothelial growths.
3. Can ALSO affect GI/Lungs.

74

HHV-8 - target patients?

AIDS/transplant patients.

75

HHV-8 - transmission?

Sexually

76

HSV - Identification?

1. Viral culture for skin/genitalia.
2. CSF PCR for herpes encephalitis.
3. Tzanck test (genital herpes) - a smear of an opened skin vesicle to detect multinucleated giant cells ==> COMMONLY SEEN IN HSV-1/HSV-2/VZV infections.
4. Infected cells also have intranuclear Cowdry A inclusions ==> HSV-1/2 + VZV.

77

Reo - envelope?

NO

78

Reo - RNA structure?

DS linear.
10-12 segments.

79

Reo - Capsid symmetry?

Icosahedral - double.

80

Reo - Medical importance?

1. Coltivirus --> Colorado tick fever.
2. Rotavirus --> #1 cause of FATAL diarrhea in CHILDREN.

81

Pircorna - envelope?

NO.

82

Picorna - RNA structure?

SS(+) linear.

83

Picorna - capsid symmetry?

Icosahedral.

84

Picorna - medical importance?

1. Polio
2. Echo --> ASEPTIC meningitis
3. Rhinovirus --> "common cold"
4. Coxsackievirus
5. HAV
PERCH.

85

Picorna - Coxsackievirus?

1. ASEPTIC meningitis
2. Herpangina (mouth blisters, fever)
3. Hand, foot, and mouth disease
4. Myocarditis
5. Pericarditis

86

Hepevirus - Envelope?

NO.

87

Hepevirus - RNA structure?

SS(+) linear.

88

Hepevirus - Capsid symmetry?

Icosahedral.

89

Hepevirus - Medical importance?

HEV

90

Calici - envelope?

NO

91

Calici - RNA structure?

SS(+) linear.

92

Calici - Capsid symmetry?

Icosahedral.

93

Calici - Medical importance?

Norovirus - Viral gastroenteritis.

94

Flavivirus - Envelope?

Yes

95

Flavi - RNA structure?

SS(+) linear.

96

Flavivirus - capsid symmetry?

Icosahedral

97

Flavivirus - Medical importance?

1. HCV
2. Yellow fever
3. Dengue
4. St.Luis encephalitis
5. West Nile virus
==> ALL ARBO.

98

Toga - Envelope?

YES

99

Toga - RNA structure?

SS(+) linear.

100

Toga - Capsid symmetry?

Icosahedral.

101

Toga - Medical importance?

1. Rubella
2. Eastern equine encephalitis = ARBO
3. Western equine encephalitis = ARBO.

102

Retroviruses - Envelope?

Yes

103

Retroviruses - RNA structures?

SS(+) linear
2 COPIES

104

Retroviruses - Capsid symmetry?

Icosahedral (HTLV)
Complex and conical (HIV)

105

Retroviruses - Medical importance?

1. Have reverse transcriptase
2. HIV
3. HTLV

106

Corona - envelope?

Yes

107

Corona - RNA structure?

SS(+) linear.

108

Corona - Capsid symmetry?

Helical.

109

Corona - medical importance?

1. Coronavirus - "common cold".
2. SARS.
3. MERS = Middle East Respiratory Syndrome.

110

Orthomyxo - envelope?

YES

111

Orthomyxo - RNA structure?

SS(-) linear - 8 SEGMENTS.

112

Orthomyxo - Capsid symmetry?

Helical.

113

Orthomyxo - Medical importance?

Influenza virus.

114

Paramyxo - Envelope?

YES

115

Paramyxo - RNA structure?

SS(-) linear - NON SEGMENTED.

116

Paramyxo - Capsid symmetry?

Helical.

117

Paramyxo - medical importance?

PaRaMyxo:
1. Parainfluenza - croup.
2. RSV - bronchiolitis in babies; Rx-Rivabirin.
3. Measles, Mumps

118

Rhabdo - envelope?

YES

119

Rhabdo - RNA structure?

SS(-) linear.

120

Rhabdo - capsid symmetry?

Helical.

121

Rhabdo - medical importance?

Rabies.

122

Filo - envelope?

YES

123

Filo - RNA structure?

SS(-) Linear.

124

Filo - capsid symmetry?

Helical

125

Filo - Medical importance?

Ebola/Marburg hemorrhagic fever --> often FATAL.

126

Arena - envelope?

Yes

127

Arena - RNA structure?

SS(+) OR SS(-) circular, 2 SEGMENTS.

128

Arena - Capsid symmetry?

Helical.

129

Arena - Medical importance?

1. LCMV - Lymphocytic choriomeningitis virus.
2. Lassa fever encephalitis - spread by RODENTS.

130

Bunya - envelope?

Yes

131

Bunya - RNA structure?

SS(-) circular - 3 SEGMENTS.

132

Bunya - Capsid symmetry?

Helical

133

Bunya - medical importance?

1. California encephalitis = ARBO
2. Sandfly/Rift valley fevers = ARBO
3. Crimean-Congo hemorrhagic fever = ARBO
4. Hantavirus - hemorrhagic fever, pneumonia

134

Arboviruses?

1. California encephalitis
2. Sandfly/Rift valley fevers
3. Crimean-Congo hemorrhagic fever

135

Delta - envelope?

Yes

136

Delta - RNA structure?

SS(-) circular.

137

Delta - Capsid symmetry?

UNCERTAIN.

138

Delta - Medical importance?

HDV is a "defective" virus that requires HBV to replicate.

139

Negative-stranded viruses - what must be done?

Must transcribe (-)strand to (+). Virion brings its own RNA-dependent RNA polymerase.

140

Negative-stranded viruses - Mention them.

1. Arena
2. Bunya
3. Paramyxo
4. Orthomyxo
5. Filo
6. Rhabdo

141

Segmented viruses?

ALL are RNA viruses:
1. Arena
2. Bunya
3. Orthomyxo
4. Reo

142

Picorna - mention the viruses:

1. Polio
2. Echo
3. Rhino
4. Coxsackie
5. HAV

143

Picorna - Special features?

1. RNA is translated into 1 large polypeptide that is cleaved by proteases into functional viral proteins.
2. Can cause aseptic (viral) meningitis (except rhinovirus and HAV).
3. ALL are ENTEROviruses (fecal-oral spread) except rhinovirus.

144

Rhinovirus - Serologic types?

>100

145

Rhinovirus - acid labile?

YES ==> DOES NOT INFECT THE GI (unlike the other picornaviruses).

146

Yellow fever virus - what type of virus?

Flavivirus (also an Arbovirus).

147

Yellow fever virus - Transmission?

Aedes mosquitoes.

148

Yellow fever virus - reservoir?

Monkey or human.

149

Yellow fever virus - symptoms?

1. High fever
2. Black vomitus
3. Jaundice

150

Rotavirus - important feature?

Major cause of acute diarrhea in the US during winter - especially in day-care centers, kindergartens.

151

Rotavirus - pathogenic mechanism?

Villous destruction with atrophy leads to decrr. absorption of Na and loss of K.

152

Influenza virus - antigens?

1. Neuraminidase (promotes progeny virion release)
2. Hemagglutinin (promotes viral entry)

153

Influenza virus - 2 important features?

1. Risk for FATAL bacterial superinfection ==> S.aureus + S.pneumo + H.flu.
2. Rapid genetic changes.

154

Influenza virus - Reformulated vaccine (the flu shot)?

Containing viral strains most likely to appear during the flu season, due to virus' rapid genetic change.

155

Influenza virus - killed viral vaccine?

Most frequently used.

156

Influenza virus - live attenuated (temperature-sensitive mutant) vaccine?

Replicates in the nose BUT NOT IN THE LUNG ==> Administered intranasally.

157

Genetic shift/antigenic shifts?

Cause PANdemics.
Reassortment of viral genome segments undergo high-frequency recombination, such as when human flu A virus recombines with swine flu A virus.

158

Genetic drift?

Causes EPIdemics.
Minor (antigenic drift) changes based on random mutation in hemagglutinin OR neuraminidase genes.

159

Rubella virus - what virus?

Toga

160

Another name for rubella?

German (3day) measles.

161

Rubella virus - disease features?

1. Fever
2. Post-auricular and other lymphadenopathy
3. Arthralgias
4. Fine, confluent rash ==> Starts on face and spreads centrifugally to invovle trunk and extremities.
Mild disease in children but serious congenital disease (ToRCHeS).

162

Congenital rubella features?

Blueberry muffin appearance ==> DERMAL extramedullary hematopoiesis.

163

Croup cough?

Seal-like barking cough.

164

Paramyxo (parainfluenza, mumps, measles, RSV) contain?

Fusion protein (F protein) --> Causes respiratory epithelial cells to fuse and form multinucleated cells.

165

Palivizumab ?

Monoclonal antibody against F protein --> prevents pneumonia caused by RSV infection in premature infants.

166

Measles - Usual presentation:

1. Prodromal fever with COUGH + CORYZA + CONJUNCTIVITIS.
2. Then, Koplik spots on buccal mucosa.
3. Followed by 1-2 days later by maculopapular rash ==> Head towards toe.

167

Measles virus - Possible sequelae?

1. SSPE - subacute sclerosing panencephalitis, occurring YEARS later.
2. Encephalitis (1:2000).
3. Giant cell pneumonia (rarely, in immunosuppressed).

168

3C's of measles:

Cough
Coryza
Conjunctivitis

169

VitA used for what in malnourished children?

Can REDUCE MORTALITY + MORBIDITY from measles.

170

Rash of measles:

Discrete erythematous rash, presents late, and includes limbs (vs rubella) as it spreads downward.

171

Mumps virus - Diseases?

1. Parotitis
2. Orchitis
3. Aseptic meningitis
4. PANCREATITIS
==> Can cause sterility especially AFTER puberty.

172

Rabies virus - characteristic shape?

Bullet-shaped.

173

Rabies virus - characteristic bodies?

Negri bodies (CYTOPLASMIC inclusions) --> Commonly found in Purkinje cells of cerebellum and in hippocampal neurons.

174

Rabies incubation period?

LONG - Weeks to months before symptom onset.

175

Rabies - Postexposure treatment?

Wound cleansing and vaccination +/- rabies immune globulin.
==> Example of PASSIVE-ACTIVE IMMUNITY.

176

Rabies - mechanism?

Travels to the CNS by migrating in a retrograde fashion up nerve axons ==> Binding to ACh RECEPTORS.

177

Rabies - Progression of disease?

Fever, malaise --> Agitation, photophobia, hydrophobia, hypersalivation --> Paralysis, coma --> Death.

178

Rabies - Transmission?

1. Bat bites
2. Raccoon bites
3. Skunk bites
than dog bites in US.
==> AEROSOL TRANSMISSION (eg bat caves) ALSO POSSIBLE.

179

HAV - Virus?

Picorna

180

HAV - incubation?

Short - weeks.

181

HBV - Virus?

DNA hepadna

182

HBV - incubation?

LONG - months.

183

HCV - virus?

Flavi

184

HDV - virus?

Delta virus

185

HDV - incubation?

Superinfection with HBV - Short.
Co-infection with HBV - Long.

186

HEV - virus?

Hepevirus.

187

Signs/symptoms of all hepatitis viruses:

1. Episodes of Fever
2. Jaundice
3. UP AST/ALT

188

Best test to detect active hep A?

Anti-HAV IgM.

189

Anti-HBc?

Antibody to HBcAg:
IgM = acute/recent infection
IgG = prior exposure or chronic infection.
POSITIVE during window period.

190

HBeAg?

A second different antigenic determinant in the HBV core.
--> Indicates active viral replication + HIGH TRANSMISSIBILITY.

191

Anti-HBe?

Antibody to HBeAg - indicates low transmissibility.

192

HBsAg(+)
HBeAg(+)
Anti-HBc = IgM

Acute HBV

193

Anti-HBe (+)
Anti-HBc = IgM

Window

194

HBsAg(+)
HBeAg(+)
Anti-HBc = IgG

Chronic HBV - High infectivity.

195

HBsAg (+)
Anti-HBe (+)
Anti-HBc =IgG

Chronic HBV - Low infectivity.

196

Anti-HBs (+)
Anti-HBe (+)
Anti-HBc = IgG

Recovery

197

Anti-HBs (+)

Immunized

198

HIV genome?

DIPLOID - 2 molecules of RNA.

199

HIV 3 structural genes?

Env, gag, pol

200

env encodes?

gp120
gp41

201

env protein formation?

Formed from cleavage of gp160 to form envelope glycoproteins.

202

gp120 role?

Attachment to host CD4+ T cell.

203

gp41 role?

Fusion and entry.

204

gag encodes?

1. p24 CAPSID PROTEIN.
2. p17 MATRIX PROTEIN.

205

gp41 role?

Capsid protein.

206

pol encodes?

1. Reverse transcriptase
2. Aspartate protease
3. Integrase

207

HIV binds which receptors on T cells?

CCR5 (early)
CXCR4 (late)
CD4

208

HIV binds which receptors on macrophages?

CCR5
CD4

209

Homozygous CCR5 mutation?

Immunity

210

Heterozygous CCR5 mutation?

Slower course

211

HIV diagnosis - which lab tests?

1. Presumptive diagnosis made with ELISA - sensitive, high false-positive rate and low threshold --> RULE OUT test.
2. (+) Results are then CONFIRMED with Western blot assay - specific, high false-negative rate and high threshold --> RULE IN test.

212

AIDS diagnosis?

1. Under 2 hundred CD4/mm^3.
2. HIV (+) with AIDS-defining condition.
3. CD4 PERCENTAGE UNDER 14%.

213

ELISA/Western blot tests look for what?

1. Antibodies to viral proteins.
2. Often FALSE(-) in the first 2 MONTHS of HIV infection.
3. FALSE(+) initially in BABIES born to infected mothers --> Anti-gp120 crosses placenta.

214

Four stages of untreated infection:

1. Flu-like (acute)
2. Feeling fine (latent)
3. Falling count
4. Final crisis

215

Common diseases of HIV(+) - Systemic - Clinical presentation?

1. Low-grade fever
2. Cough
3. HSM
4. Tongue ulcer

216

Common diseases of HIV (+) - Systemic - Lab findings?

Oval yeast cells within macrophages, CD4<100cells/mm3.

217

Common diseases of HIV(+) - Systemic - Pathogen?

Histoplasma capsulatum (Causes only pulmonary symptoms in immunocompetent hosts).

218

Common diseases of HIV(+) - Dermatologic - Clinical presentation?

1. Fluffy white cottage-cheese lesions --> C.albicans
2. Hairy leukoplakia --> EBV.
3. Superficial vascular proliferation --> B.henselae

219

HIV (+) diseases - lab findings - Pseudohyphae, commonly oral if CD4<100?

C.albicans --> causes oral thrush and esophagitis.

220

HIV(+) diseases - findings - hairy leukoplakia often on LATERAL TONGUE?

EBV

221

Bartonella henselae causes?

Bacillary angiomatosis.

222

HIV(+) disease - GI presentation?

Chronic, watery diarrhea - Cryptosporidium spp.

223

Cryptosporidium diarrhea - findings?

1. Acid-fast cysts seen in stool.
2. Especially when CD4<200cells/mm3.

224

HIV(+) diseases - T.gondii?

Abscesses --> many ring-enhancing lesions on imaging.

225

CD4 for T.gondii?

CD4<100

226

HIV(+) dementia?

Directly associated with HIV - Must differentiate from other causes.

227

HIV(+) encephalopathy?

JC virus reactivation (cause of PML) --> Due to reactivation of latent virus.
Results in demyelination.

228

CD4 for JC reactivation?

CD4<200

229

C.neoformans meningitis in HIV(+) - Findings?

India ink stain reveals yeast with narrow-based budding and large capsule.

230

CD4 for C.neoformans?

CD4<50.

231

HIV(+) CMV retinitis - findings?

Cotton-wool spots on fundoscopic exam and may also occur with esophagitis.

232

CD4 for CMV retinitis?

CD4<50.

233

HIV(+) NHL (large cell type) ?

Often on oropharynx (Waldeyer ring) - May be associated with EBV.

234

HIV(+) primary CNS lymphoma?

1. Focal or multiple, differentiate from toxoplasmosis.
2. May be associated with EBV.

235

HIV(+) SCC?

HPV - Often in anus (gays) or cervix.

236

HIV(+) superficial neoplastic proliferation of vasculature?

HHV-8 - Biopsy reveals LYMPHOCYTIC INFLAMMATION.
Do not confuse with bacillary angiomatosis caused by B.henselae (neutrophils).

237

HIV(+) interstitial pneumonia CMV?

Biopsy reveals cells with intranuclear (owl eye) inclusion bodies.

238

Invasive aspergillosis - HIV(+)?

Aspergillus fumigatus - Pleuritic pain, hemoptysis, infiltrates on imaging.

239

PCP ?

1. Especially when CD4<200.
2. Ground-glass appearance on imaging.
3. P.jirovecii

240

Pneumonia in HIV(+)?

1. Generally when CD4>200.
2. S.pneumoniae

241

TB-like disease in HIV(+)?

1. Especially with CD4<50.
2. M.avium-intracellulare - also known as MAC.

242

Prion diseases - etiology?

Conversion of a normal (predominantly alpha-helical) protein termed prion protein (PrPc) to a β-pleated form (PrPsc), which is transmissible:
1. CNS-related tissue --> Iatrogenic CJD
2. Food contaminated by BSE-infected animal products (variant CJD)

243

PrPsc does what?

Resists PROTEASE DEGRADATION and facilitates the conversion of still more PrPc to PrPsc.

244

Accumulation of PrPsc results in what?

1. Spongiform encephalopathy
2. Dementia
3. Ataxia
4. Death

245

Types of spongiform encephalopathy?

1. CJD ==> Rapidly progressive dementia, typically sporadic (some familial forms).
2. Bovine spongiform encephalopathy (BSE) ==> "Mad cow disease".
3. Kuru ==> Acquired prion disease noted in tribal populations practicing human cannibalism.