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1
Q

4th most common nosocomial blood infection

A

candida

2
Q

Oval or spherical shaped, unicellular organisms

A

yeasts

3
Q

Multicellular with branching, thread like filaments (hyphae) that knit to form a mat-like structure (mycelium)

A

mold

4
Q

dimorphic

A

can exist as either a yeast or a mold form - depending on conditions

5
Q

heterotrophic

A

reliant on their environment for nutrients and other required & essential substances

6
Q

telemorph

A

sexual reproduction of yeast

7
Q

anamorph

A

asexual reproduction of yeast

8
Q

What MOA can you not use in fungus?

A

protein synthesis inhibitors because it’s too close to our protein synthesis

9
Q

Azotemia

A

seen with amphotericin in ~80%. Decreased renal function. abnormally high levels of nitrogen-containing compounds such as urea or creatinine. It is largely related to insufficient filtering of blood by the kidneys. It can lead to uremia if not controlled

10
Q

azole MOA

A

Inhibits ergosterol formation

blocks lanosterol->ergosterol

11
Q

azole with the least CYP450 interaction

A

Posaconazole

12
Q

echinocandin with the least CYP12450 interaction

A

Anidulafungin

13
Q

griseofulvin MOA

A

inhibiting microtubule so disrupts flow and movement inside cell also disrupts mitosis

14
Q

endemic mycoses

A

able to cause disease in healthy hosts; only present in certain areas

15
Q

opportunistic mycoses

A

cause disease if your immune system isn’t working correctly; can get regardless of where you live

16
Q

endemic mycoses ex:

A

histoplasmosis
blastomycosis
coccidioidomycosis

17
Q

opportunistic mycoses ex:

A

candidiasis
cryptococcosis
aspergillosis

18
Q

risk factors for fungal infections

A
  1. organ & bone transplant
  2. cytotoxic chemo
  3. indwelling IV catheters, burns, surgery or trauma
  4. broad-spectrum ABX
19
Q

candida that is resistant to fluconazole

A

C. krusei

C. glabrata- somewhat resistant- need high doses

20
Q

candidemia

A

candida in the blood

21
Q

positive germ tube test

A

indicates C. albicans in healthy person

or could be C. dubliniensis in HIV

22
Q

all patients with candidemia require

A

eye exam to rule out candida endophthalmitis

23
Q

fluconazole treatment for C. albicans, C. parapsilosis, C. tropicalis

A

6mg/kg/day

24
Q

fluconazole treatment for C. glabrata

A

12mg/kg/day

DO NOT USE for C. krusei

25
Q

predisposing factors for aspergillosis

A
prolonged neutropenia (>7 days)
chronic high dose steroids
cytotoxic agents- chemo
broad spectrum ABX
cell transplantation
26
Q

galactomannan postitve test

A

diagnostic of aspergillosis

27
Q

unique CT scan

A

halo signs i n aspergillosis

28
Q

empiric therapy for aspergillosis

A

1st line: voriconazole

2nd line: lipid form Amp B

29
Q

salvage therapy in Aspergillosis

A

vori + echinocandin
lipid Amp B + echinocandin
or posaconazole

30
Q

primary cryptococcosis presentation

A

always in the lungs- lungs, rales (rattling), SOB

31
Q

Cryptococcal meningitis presentation

A

more serious
kernig’s & Brudzinki’s sign
in AIDs pts sxs are less specific

32
Q

cryptococcosis diagnosis

A

cryptococcal antigen test or analysis of CSF- fungal (>lymphocytes)

33
Q

cryptococcus pulmonary mild-moderate treatment

A

fluconazole

alt: itraconazole, ampB

34
Q

cryptococcus severe pulmonary and CNS treatment

A

induction: ampB+ flucytosine +/- fluconazole
alt: mono lipid ampB
maintenance: only in AIDs pts- fluconazole until CD4>200

35
Q

what should NOT be used to treat cryptococcus?

A

echinocandins

36
Q

histoplasmosis is an endemic in

A

Ohio & mississippi river valleys

37
Q

histoplasmosis diagnosis

A

antigent test- quick
direct mircoscopic exam w/ 10% KOH
histopathologic exam & culture

38
Q

histoplasmosis mild-moderate treatment

A

treatment is usually not needed unless symptoms > 1 month

itraconazole

39
Q

histoplasmosis moderately severe-severe treatment

A

ampB 1-2weeks then itraconazole

methylprednisolone 1-2 weks with acute respiratory complications

40
Q

blastomycosis endemic in

A

Ohio and mississippi river valleys

41
Q

acute pulmonary blastomycosis is either

A

asymptomatic or self-limited

stays in your system & will be reactivated “disseminate”

42
Q

reactivation of blastomycosis

A

chronic pulmonary- weight loss, TB, CNS involvement

43
Q

blastomycosis pulmonary disseminated disease (non-CNS) Mild-moderate treatment

A

itraconazole

44
Q

blastomycosis pulmonary disseminated disease (non-CNS) life-threatening treatment

A

ampB for 1-2 weeks then itraconazole

45
Q

blastomycosis CNS disease

A

ampB (lipid form preferred) then azole (flu, itra, vori)

46
Q

histoplasmosis/blastomycosis response to therapy by:

A
  1. resolution of radiologic, serologic, & micro parametes

2. improvement in SXS

47
Q

histoplasmosis/blastomycosis: after initial course of therapy in AIDs pts:

A

lifelong suppressive therapy with oral azoles until CD4>200

48
Q

asymptomatic histoplasmosis

A

do NOT treat

can treat blastomycosis

49
Q

risk factors for primary coccidiodomycosis

A

non identified

50
Q

risk factors for severe coccidiodomycosis

A

very serious infection

race, prego, immuno-compromised, male, neonates, pts w/ B/AB blood

51
Q

clinical presentation of coccidiodomycosis

A

60% asymptomatic, primary pneumonia, chronic persistent pneumonia- hemoptysis(coughing blood), valley fever-rash, disseminated disease- CNS

52
Q

coccidiodomycosis asymptomatic treatment

A

NO treatment

53
Q

Coccidiodomycosis primary respiratory or disseminated (non-CNS) infection treatment

A

azole- first line fluconazole or itraconazole for bone disease
ampB
duration- months to years; sometimes lifelong suppressive therapy

54
Q

coccidiodomycosis disseminated CNS treatment

A

fluconazole for life
amp B intrathecal therapy +/- itra or fluconazole
itra for life

55
Q

good CSF penetration fungal agents

A

fluconazole, voriconazole, fluctosine

56
Q

flucytosine MOA

A

enters fungal cells by a cytosine-specific permease & disrupts nucleic acids by inhibiting thymidylate synthetase

57
Q

flucytosine has a synergistic effect with:

A

AmB

58
Q

Black box warning for itraconazole

A

In patients with heart failure due to ionotropic effect

59
Q

host range

A

which host can be infected determined by specific binding of the virus to the cell

60
Q

what are the three classes of viruses?

A

DNA, RNA & retroviral

61
Q

DNA virus examples

A

smallpox, chickenpox, herpes, hep B, CMV, HPV

62
Q

RNA virus examples

A

rabies, polie, influenza, colds, MMR, Hep A & Hep C

63
Q

RNA retroviral virus examples

A

HIV & human T-cell leukemia

64
Q

RNA virus MOA

A

replicate entirely in host cytoplasm

65
Q

uncoating

A

the release of viral nucleic acids

66
Q

current agents _____ eliminate dormant viruses

A

do NOT

67
Q

acyclic guanosine analogs lack

A

a cyclic sugar (ribose)

68
Q

acyclic guanosine analog drugs

A

acyclovir,valacyclovir, penciclovir, famciclovir, ganciclovir, valganciclovir

69
Q

acyclic guanosine analog MOA

A

viral thmidine kinase adds first PO4 and then host cell kinase ass the other 2. Gets incorporated into viral DNA. Has no 3’OH so DNA chain is terminated!

70
Q

cidofovir is an analog of

A

cytidine

71
Q

cidofovir already has one P, so it

A

bypasses the need for viral thymidine kinase

72
Q

cidofovir diphosphate (3Ps) inhibits

A

DNA polymerase & also is a chain terminator (no 3’OH)

73
Q

foscarnet MOA

A

inhibits viral nucleic acid synthesis by noncompetitive inhibition of the pyrophosphate binding site on viral DNA polymerase

74
Q

first FDA approved antisense therapy for viral infection

A

fomivirsen

75
Q

rimantadine & amantadine MOA

A

inhibit viral uncoating & assembly of new components. Active against Influenza A. cyclic cage structure

76
Q

analogs of sialic acid

A

oseltamivir & zanamivir

flu A & B incl H1N1

77
Q

oseltamivir & zanamivir MOA

A

inhibit neuraminidase & block release of progeny virus from host cell

78
Q

antiviral agents used to treat Hep B & C

A

adefovir
recombinant & natural IFNs
lamivudine & telbivudine
ribavirin

79
Q

acyclic adenosine monophosphate analog

A

adefovir

80
Q

Lamivudine & telbivudine MOA

A

nucleoside analogs of C & T. block chain elongation

81
Q

in contrast with other agents, ribavirin has

A

a ribose sugar.

82
Q

ribavirin MOA

A

inhibits the enzyme inosine-5-PDH which decreases synthesis of GTP. Also inhibits post-transcriptional processing of viral mRNA (5’ capping)

83
Q

herpes zoster aka

A

shingles

84
Q

shingles is characteristically

A

unilateral

85
Q

postherapetic neuralgia (PHN)

A

pain that persists >120 days after onset of shingles rash

86
Q

treatment of shingles recommended in:

A

> 50yo, more severe cases, immunocompromised

87
Q

goals of shingles treatment

A

accelerate resolution, limit severity & duration of pain & reduce risk of complications

88
Q

steroids & antivvirals do NOT prevent

A

postherpetic neuralgia

89
Q

prevention of CMV

A

valganciclovir, possibly ganciclovir, brincidofovir underinfestigation

90
Q

CMV treatment

A

ganciclovir & valganciclovir are first line

91
Q

antigenic drift

A

a mechanism for variation in viruses that involves the accumulation of mutations within the genes that code for antibody-binding sites.

92
Q

antigenic shift

A

the process by which two or more different strains of a virus, or strains of two or more different viruses, combine to form a new subtype having a mixture of the surface antigens of the two or more original strains.. larger change

93
Q

7th leading cause of death in the US

A

influenza

94
Q

immunity to influenza ___ develops in childhood

A

c

95
Q

hemagluttin (Hx)

A

involved in host cell binding prior to viral entry

96
Q

neuramidase (Nx)

A

necessary for viral release and propagation

97
Q

____ flu vaccine recommended in children 2-8 if available

A

live attenuated

98
Q

influenza prophylactic agents

A

oseltamivir, zanamivir

99
Q

pts who should receive prophylaxis or therapy for flu

A

hospitalized pts, pts with severe, complicated or progressive illness, pts which higher risk of flu complications