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Flashcards in Micro 4 USMLE Deck (170)
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1
Q

this is an enveloped, single stranded RNA virus with a segmented genome, with a vaccine, that commonly causes illness every winter

A

influenza virus

2
Q

what 2 antigens does the influenza virus contain?

A

hemagglutinin and neuraminidase

3
Q

the influenza virus is responsible for worldwide influenza epidemics. It has rapid genetic changes and puts pts at risk for a fatal ________ superinfection.

A

bacterial.

4
Q

this type of viral influenza vaccine is the major mode of protection. It is reformulated yearly and offered in the fall to health care workers and the elderly

A

killed

5
Q

this type of genetic change involves teh reassortment of viral genome (such as when human flu A virus combines with the swine flu A virus)

A

genetic shift

6
Q

this type of genetic change involves minor changes based on random mutation

A

genetic drift.

7
Q

what is more deadly a genetic shift or drift.

A

mneu: Sudden Shift is more deadly than a graDual Drift

8
Q

give two Rxs for tx and prophylaxis of influenza A

A

Amantidine & Rimantadine

9
Q

Give 2 neuraminidase inhibitors that are useful to tx both influenza A & B

A

Zanamivir and oseltamivir

10
Q

pt presents with strange behavior, seizures, and fear of water, 2 mo after being bit by racoon. He dies quickly of fatal encephalitis. What is the bullet shaped virus that travels to the CNS by migrating in a retrograde fashion up nerve axons

A

rabies

11
Q

what are the characteristic cytoplasmic inclusions in neurons infected by the rabies virus

A

negri bodies

12
Q

these viruses are transmitted by arthropods (mosquitoes, ticks). Classic examples are dengue fever (aka break bone fever) & yellow fever. Note: A varient of dengue fever in Southeast Asia is hemorrhagic shock syndrome

A

Arboviruses

mneu: ARBOvirus - ARthropod-BOrne virus.

13
Q

Give 2 arboviruses

A

flavivirus, togavirus, and bunyavirus

14
Q

pt presents with a high fever and juandice. Wife reports he has been vomiting black stuff. His dz is caused by the flavivirus, and arbovirus transmitted by the Aedes mosquito with a monkey or human resevior.

A

Yellow Fever

15
Q

flavi=______

A

yellow

16
Q

what charicteristic acidophilic inclusions would you expect to see in the liver of a pt with yellow fever

A

councilman bodies

17
Q

Name the herpesviruses

A

CMV
HSV1,2
EBV
VZV

mneu: get herpes in a CHEVrolet

18
Q

this herpes virus causes gingivostomitis, keratoconjunctivitis, temporal lobe encephalitis, herpes labiales via respiratory secretion and saliva

A

HSV-1

19
Q

this herpes virus causes herpes genitalis and neonatal herpes via sexual contact and perinatal transmission

A

HSV-2

20
Q

this herpes virus causes shingles, encephalitis, and pneumonia via respiratory secretions

A

VZV

21
Q

this herpes virus causes infectious mononucleosis & Burkitt’s lymphoma via respiratory secretions and saliva

A

EBV

22
Q

this herpes virus causes congenital infection, mononucleosis (negative monospot), and pneumonia via congenital, transfusion, sexual contact, saliva, urine, or transplant transmission

A

CMV

23
Q

this herpes virus causes Kaposi’s aarcoma in HIV pts via sexual contact

A

HHV-8

24
Q

18 y/o female presents wtih fever, hepatosplenomegaly, pharyngitis, and posterior auricular lymphadenopaty. What virus and what dz?

A

EBV (herpes virus)

Mononucleosis

25
Q

what test should you do to detect mononucleosis and what antibody does it detect

A

Monospot test

tests for heterophil antibodies by agglutination of sheep RBCs

26
Q

what atypical lymphocytes are circulating in the blood of a pt with mononucleosis.

A

cytotoxic T cells

27
Q

what viruses does a Tzank test detect

A

HSV-1,2, & VZV

mneu: Tzank heavens I do not have herpes or varicella

28
Q

In a tzank test you take a smear of an opened skin vesicle to detect this

A

multiniucleated giant cell.

29
Q

what hepatitis virus:
this RNA picornavirus is transmitted primarily by fecal-oral route. There is a short incubation period (usually 3 weeks) and No carrieres.

A

Hep A

mneu: Hep A-Asymptomatic (usually), Acute, Alone (no carriers; naked ssRNA)

30
Q

what hepatitis virus: This DNA hepadnavirus is transmitted primarily by parenteral, sexual, and maternal-fetal routs. It has a long incubation (3 mo). There are carriers. Reverse transcription occurs; however, the virion enzyme is a DNA-dependent DNA polymerase

A

Hep B

mneu: hep B is Blood borne

31
Q

what hepatitis virus: This RNA flavivirus is transmitted primarily via blood and resembles HBV in its course and severity. Carriers. Common cause of IV drug use hepatitis in the US

A

Hep C

mneu: Hep C: Chronic, Cirrhosis, Carcinoma, Carieres

32
Q

what hepatitis virus:

this delta agent is a defective virus that requires HBsAg as its envelope. Carriers.

A

Hep D

mneu: Hep D: Defective, Dependent on HBV

33
Q

what hepatitis virus:
this RNA calicivirus is transmitted enterically and causes water-borne epidemics. It resembles HAV in course, severity, incubation. There is a high mortality rate in pregnant women

A

Hep E

mneu: Hep E: enteric, expectant mothers, epidemics

34
Q

Hep ___ & ____ are spread via the fecal-oral route

A

A & E

mneu: the vowels hit your bowels.

35
Q

Hep ___ & ____ predispose a pt to chronic active hepatitis, cirrhosis, and hepatocellular carcinomai

A

B & C

36
Q

Hepatitis serologic markers:

best test to detect active hep A

A

IgM HAV Ab

37
Q

Hepatitis serologic markers: continued presence indicates carrier state of hep B

A

HBsAg (Ag found on surface of HBV)

38
Q

Hepatitis serologic markers: PROVIDES IMMUNITY to hep B

A

HBsAb (Ab to HBs Ag)

39
Q

Hepatitis serologic markers: Ag assoc. w/ core of HBV

A

HBcAg

40
Q

Hepatitis serologic markers: positive during WINDOW PERIOD of Hep B infection

A

HBcAb

41
Q

Hepatitis serologic markers: A second different antigenic determinant in the HBV core. Important indicator of transmissibility

A

HBeAg

mneu: BEware

42
Q

Hepatitis serologic markers: Antibody to e antigen. Indicates low transmissibility of hep B

A

HBeAb

43
Q

HBsAg will be + if pt is either in ______ or _______ Hepatitis B

A

acute or chronic (carrier)

44
Q

HBsAb is + only when pt has _________ from hep B

A

completely recovered

45
Q

this test rises about 2 mo after hep B exposure and remains + after complete recovery

A

HBcAg

46
Q

HIV has a ______ genome (2 molecules of RNA)

A

diploid

47
Q

HIV capsid is made of ______ (a rectangular nucleocapsid protein)

A

p24

48
Q

HIV surface has these 2 envelope proteins

A

gp41 & gp120

49
Q

image p 159 HIV

A

50
Q

1st test given for HIV is this. It is a sensitive test with a high false positive rate and a low threshold (RULE OUT TEST).

A

ELISA

51
Q

After pt tests + with the ELISA test dx of HIV is confirmed by this test. This test is more specific, it has a high false - rate and a high threshold (RULE IN TEST)

A

Western blot assay

52
Q

these test allows the physician to monitor the effect of drug therapy on viral load.

A

HIV PCR/ viral load tests

53
Q

Elisa/Western blot tests look for antibodies to viral proteins. These tests are often falsy negative when?

A

first 1-2 mo of HIV infections

54
Q

Elisa/Western blot tests look for antibodies to viral proteins. These tests are often falsy positive when?

A

babies born to infected mothers (anti-gp120 crosses the placenta0

55
Q

when is someone considered as having AIDS (3)

A

1) =/< 200 CD4 count
2) HIV+ w/ indicator conditon (e.g., PCP
3) CD4/CD8 ratio <1.5

56
Q

1% of caucasions are homozygous for this mutation granting them immunity from HIV virus (20% are heterozygous leading to slower course)

A

CCR5 mutation

57
Q

this mutation is associated with a rapid progression to AIDS

A

CXCR1

58
Q

image 160-time course of HIV infection

A

59
Q

give 3 opportunistic infections or dzs that attack the brain in AIDS

A

cryptococcal meningitis, toxoplasmosis, CMV encephalopathy, AIDS dementia, PML

60
Q

PML is associated with what virus

A

JC virus

61
Q

give 1 opportunistic infection or dz that attacks the eyes in AIDS

A

CMV retinitis

62
Q

give 3 opportunistic infections or dzs that attack the mouth and throat in AIDS

A

Thrush, HSV, CMV, oral hairy leukoplakia

63
Q

what organism causes thrush

A

candida albicans

64
Q

what virus causes oral hairly leukoplakia

A

EBV

65
Q

give 3 opportunistic infections or dzs that attack the lungs in AIDS

A

pneumocystis carinii pneumonia (PCP), TB, histoplasmosis

66
Q

give 3 opportunistic infections or dzs that attack the GI system in AIDS

A

cryptosporidosis, mycobacterium avium-intracellulare complex, CMV colitis, non-hodgkins lymphoma

67
Q

what virus can cause non-Hodgkin’s lymphoma in AIDS

A

EBV

68
Q

give 2 opportunistic infections or dzs that attack the skin in AIDS

A

shingles, kaposi sarcoma

69
Q

what virus causes shingles

A

VZV

70
Q

what virus causes Kaposi’s sarcoma

A

HHV-8

71
Q

give 3 opportunistic infections or dzs that attack the genitals in AIDS

A

genital herpes, warts, and cervical cancer

72
Q

what virus can lead to cervical cancer

A

HPV

73
Q

these are infectious agents that do not contain RNA or DNA (consist only of proteins). They are encoded by cellular genes.

A

PRions

74
Q

give 3 examples of diseases caused by prions

A

Creutzfeldt-Jakob dz (CJD)
Kuru
Scrapie
“Mad cow dz”

75
Q

this dz caused by prions results in rapid progressive dementia

A

CJD

76
Q

Prions are associated with this brain damage

A

spongiform encephalopathy.

77
Q

normal prions have this type of conformation; pathologic prions (like CJD) are this conformation.

A

alpha helix

Beta pleated sheets

78
Q

Give the dominant normal fora for the body location: skin

A

staphylococcus epidermidis

79
Q

Give the dominant normal fora for the body location: nose

A

S. aureus

80
Q

Give the dominant normal fora for the body location: oropharynx

A

viridans streptococci

81
Q

Give the dominant normal fora for the body location: dental plaque

A

streptococcus mutans

82
Q

Give the dominant normal fora for the body location: colon

A

bacteroides fragilis> e. coli

83
Q

Give the dominant normal fora for the body location: vagina

A

lactobacillus, colonized by E. coli and group B strep

84
Q

T or F: Neonates delivered by cesaerean section have no flora but are rapidly colonized after birth

A

T

85
Q

Give the dominant normal fora for the body location: vagina

A

lactobacillus, colonized by E. coli and group B strep

86
Q

T or F: Neonates delivered by cesaerean section have no flora but are rapidly colonized after birth

A

T

87
Q

common causes of pneumonia in children 6 wks -18 yrs

A

viruses (RSV)
mycoplasma
Chlamydia pneumoniae
Streptococcus pneumoniae

88
Q

common causes of pneumonia in adults (18-40 y/o)

A

mycoplasma
C. pneumoniae
S. pneumoniae

89
Q

common causes of pneumonia in adults (40-65 y/o)

A
S. pneumoniae
H. influenzae
Anaerobes
Viruses
Mycoplasma
90
Q

common causes of pneumonia in the elderly

A
S. pneumoniae
Viruses
Anaerobes
H. influenzae
gram negative rods
91
Q

common causes of pneumonia in the hospital

A

Staphylococcus, gram-negative rods

92
Q

common causes of pneumonia in immunocompromized

A

staphylococcus, G- rods, fungi, viruses, PCP (HIV)

93
Q

common causes of pneumonia after aspiration

A

anaerobes

94
Q

common causes of pneumonia in alcoholics or IV drug users

A

S. pneumoniae, Klebsiella, Staphylococcus

95
Q

common causes of pneumonia in alcoholics or IV drug users

A

S. pneumoniae, Klebsiella, Staphylococcus

96
Q

common causes of pneumonia in postviral infections

A

staphylococcus, H. influenzae

97
Q

common causes of pneumonia in the neonate

A

Group B streptococci, E. coli

98
Q

common causes of atypical pneumonia

A

mycoplasma, legionella, chlamydia

99
Q

Common causes of meningitis in the newborn (0-6mo)

A

GROUP B STREPTOCOCCI
E. COLI
Listeria

100
Q

Common causes of meningitis in children (6 mo- 6yrs)

A

Streptococcus pneumoniae
Neisseria meningitidis
H. influenzae type B
Enteroviruses

101
Q

Common causes of meningitis in ages 6-60 y/o

A

N. MENINGITIDIS
Enteroviruses
S. Pneumoniae
HSV

102
Q

Common causes of meningitis in 60 + y/o

A

S. PNEUMONIA
G - rods
Listeria

103
Q

Common causes of meningitis in HIV

A

cryptococcus
CMV
toxoplasmosis (brain abscess)
JC virus (PML)

104
Q

incidence of this type of meningitis has greatly decreased after the introduction of the vaccine within the last 10-15 years

A

H. influenzae

105
Q

On LP pt has increased PMNs, increased, protein, and decreased sugar. CSF pressure is increased. What kind of meningitis is this?

A

bacterial

106
Q

On LP pt has increased lymphocytes, increased, protein, and decreased sugar. CSF pressure is increased. What kind of meningitis is this?

A

fungal or TB

107
Q

On LP pt has increased lymphocytes, normal protein, and normal sugar. CSF pressure is normal. What kind of meningitis is this?

A

viral

108
Q

osteomylitis is usually caused by what bug

A

S. aureus

109
Q

osteomylitis in sexually active pts is rearely caused by this organism but they may be infected with this bug and have septic arthritis.

A

N. gonorrheae

110
Q

osteomylitis usually occurs in this age group

A

children

111
Q

osteomylitis in diabetics and drug addics is often due to this bug

A

pseudomonas aeruginosa

112
Q

osteomylitis in pts with sickle cell anemia is often due to this bug

A

salmonella

113
Q

osteomyelitis in pts with sickle cell often presents with this elevated lab value

A

ESR

114
Q

osteomylitis in pts with prosthetic replacement is often due to these bugs

A

S. aureus & S. epidermis

115
Q

vertebral osteomylitis (Potts dz) is due to this bug

A

Mycobacterium tuberculosis

116
Q

urinary tract infections in ambulatory pts is most often due to this bug

A

E-coli (50-80%)

Klebsiella (10%)

117
Q

2nd most common urinary tract infection young ambulatory women after E. Coli

A

Staphylococcus saphrophyticus

118
Q

urinary tract infections in hospitalized pts

A

E. coli, proteus, klebsiella, serratia, pseudomonas

119
Q

ratio of UTIs: women to men

A

10:1 (short urethra colonized by fecal flora)

120
Q

urinary tract infections are usually caused by ascending infections. T or F

A

T

121
Q

male baby presents with UTI what do you suspect

A

congenital defect

122
Q

elderly male presents with UTI. what do you suspect

A

enlarged prostate

123
Q

symptoms of UTI

A

dysuria, frequency, urgency, suprapubic pain

124
Q

pt presents with fever, chills, flank pain, and CVA tenderness. What do you suspect?

A

pyelonephritis

125
Q

some strains of this bug that causes UTI result in a red pigment. Often these infections are nosocomial and Rx resistant.

A

Serratia marcescens

126
Q

this is the leading cause of UTI. Colonies show a metalic sheen on EMB agar

A

E. coli.

127
Q

This UTI bug is often nosocomial and drug resistant

A

Enterobacter cloacae

128
Q

this bug that causes UTIs has a large mucoid capsule and viscous colonies

A

Klebsiella pneumoniae

129
Q

this bug that causes UTIs has motility and causes “swarming” on agar. It produces urease and is associated with struvite stones

A

Proteus mirabilis

130
Q

this bug that causes UTIs produces a blue green pigment and a fruity odor. It is usually nosocomial and drug resistant

A

Pseudomonas aeruginosa

131
Q

If the nitrite test is postitive what kind of bacteria are you looking at

A

G-

132
Q

if the leukocyte esterase test is + what type of bug are you looking at

A

bactreial

133
Q

UTI bugs can be memorized by the mneumonic–SSEEK PP

A
Serratia marcescens
Staphylococcus 
Escherichia coli
Enterobacter cloacae
Klebsiella pneumoniae
Proteus mirabilis
Pseudomonas aeruginosa
134
Q

pt presents with urethritis, cervicitis, PID, prostitis, epididymitis, arthritis, and a creamy purulent discharge. What is the dz and the organism?

A

Gonorrhea

Neisseria gonorrheae

135
Q

Pt presents with a painless chancre. What is the dz and the organism?

A

Treponema pallidum

primary syphilis

136
Q

pt presents with fever, lymphadenopathy, skin rashes, condylomata lata. What is the dz and the organism?

A

treponema pallidum

secondary syphilis

137
Q

pt presents with gummas, tabes dorsalis, general paresis, aortitis, and argyll robertson pupil. What is the dz and the organism?

A

treponema pallidum

tertiary syphilis

138
Q

pt presents with painful penile, vulvar or cervical ulcer. What is the dz and the organism?

A

genital herpes

HSV-2

139
Q

Pt presents with urethritis, cervicitis, conjunctivitis, Reiter’s syndrome, PIDWhat is the dz and the organism?

A
Chlamydia trachomatis (D-K)
chlamydia
140
Q

pt presents with ulcers, lymphadenopathy and rectal strictures What is the dz and the organism?

A

lymphogranuloma venerium

C. trachomatis (L1-L3)

141
Q

Pt presnts with vaginitis and strawberry colored mucosa. What is the dz and the organism?

A

trichomoniasis

trichomonas vaginalis

142
Q

pt presents with opportunistic infections, Kaposi’s sarcoma, lymphoma. What is the dz and the organism?

A

AIDS

HIV

143
Q

Pt presents with genital warts and koiocytes. What is the dz and the organism?

A

condylomata acuminata

HPV 6 & 11

144
Q

Pt presents with juandice What could the STD be and the organism?

A

HBV

hepatitis B

145
Q

pt presents with a painful genital ulcer and inguinal adenopathy. What is the dz and the organism?

A

Haemophilis ducreyi

Chancroid

146
Q

Pt preents with a noninflammatory, malodorous discharge; positive whiff test, and clue cells. What is the dz and the organism?

A

bacterial vaginosis

gardnerella vaginalis

147
Q

this organism is most likely to cause a subacute undiagnosed pelvic inflammatory dz

A

chlamydia trachomatis

148
Q

this bug can often causes an acute high fever PID

A

Neisseria gonorrhea

149
Q

this cause of PID is the most common STD in the US (3-4 million cases per year).

A

C. trachomatis

150
Q

pt presents with cervical motion tenderness (chandelier sign) purulent cervical discharge. Pt may have salpingitis, endometritis, hydrosalpinx, and tubo-ovarian abscess

A

PID

151
Q

salpingitis is a risk factor for the following (give 2)

A

ectopic pregnancy, infertility, chronic pelvic pain, and adhesions

152
Q

see clue cells on a prep what STD do you think

A

Gardnerella

153
Q

see motile on wet prep what STD do you think

A

Trichomonas

154
Q

2 most common nosocomial infections are:
UTI due to ______
Wound infection due to ______

A

E.coli

S.aureus

155
Q

most common pathogens causing nosocomial infections in the newborn nursery are (2)

A

CMV & RSV

156
Q

most common pathogens causing nosocomial infections in urinary catheterization are

A

E. coli, Proteus mirabilis

157
Q

most common pathogen causing nosocomial infections in respiratory therapy equiptment is?

A

pseudomonas aeruginosa

mneu: presume pseudomonas AIruginosa when AIR or burns are involved

158
Q

most common pathogens causing nosocomial infections in renal dialysis unit

A

HBV

159
Q

most common pathogens causing nosocomial infections in hyperalimentation

A

candida albicans

160
Q

most common pathogens causing nosocomial infections in water aerosols

A

legionella

mneu: legionella when water source is involved

161
Q

Infections dangerous in pregnancy–ToRCHeS

A
Toxoplasma
Rubella, 
CMV
HSV/HIV
Syphilis
162
Q

If all else fails think this if dealing with pus, empyema, or an absess

A

S. aureus

163
Q

If all else fails think this if dealing with a pediatric infection

A

H. influenzae

164
Q

If all else fails think this if dealing with pneumonia in CF or a burn infection

A

pseudomonas aeruginosa

165
Q

If all else fails think this if dealing with branching rods in oral infection

A

actinomyces israelii

166
Q

If all else fails think this if dealing with a traumatic open wound

A

Clostridium perfringes

167
Q

If all else fails think this if dealing with a surgical wound

A

S. aureus

168
Q

If all else fails think this if dealing with dog or cat bite

A

pasteurella muticocida

169
Q

If all else fails think this if dealing with currant jelly sputum

A

klebsiella

170
Q

If all else fails think this if dealing with spesis/meningitis in newborn

A

group B strep