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UWorld Journal > Infectious Diseases > Flashcards

Infectious Diseases Flashcards

1
Q

what is selective IgA deficiency

A

most common primary immunodeficiency

*symptoms: recurrent sinopulmonary and gastrointestinal infection due to absence of secretory IgA

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2
Q

silicosis impairs the __________ of cell-mediated immunity.

A

macrophage effector arm

  • internalized silica particles disrupt macrophage phagolysosomes to release the particles and viable mycobateria
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3
Q

mechanism of action of cromolyn and nedocromil

A

inhibit mast cell degranulation

prevent release of preformed chemical mediators

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4
Q

essential pathogenic mechanism for Shigella infection

A

mucosal invasioin- they invade the gastrointestinal mucosa, particularly the M cells that overlie Peyer’s patches–> induce apoptosis of host cell and spread to adjacent cells

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5
Q

Listeria is not sensitive to _________ so it an be treated with ________

A

cephalosporins; ampicillin

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6
Q

mechanism of action of diphtheria exotoxin

A

ribosylation inactivates elongation factor-2, thereby inhibiting protein synthesis and causing cell death

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7
Q

recurrences of genital herpes can be reduced with _______

A

daily treatment of oral valacyclovir, acyclovir, or famciclovir

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8
Q

how to prevent congenital rubella syndrome

A

vaccination with live-attenuated rubella virus vaccine

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9
Q

first-line treatment for Enterobiasis (enterobius vermicularis) aka pinworm for perianal itching in kids

A

Albendazole

or pyrantel pamoate for pregnant patients

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10
Q

bacteria that are resistance to drugs that attack the peptidoglycan cell wall (d-alanine-D-alanine analog)

A

Mycoplasma genus since they lack peptidoglycan cell walls

an be treated with anti-ribosomal agents (eg, tetracycline, macrolides)

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11
Q

Bacillary angiomatosis can be caused by _______ infection

A

bartonella henselae

*red-purple papular skin lesions ( can be fatal)

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12
Q

virulence factor for Haemophilus influenzae type b (Hib)

A

polyribosylribitol phosphate= capsule component

Hib is the most common cause of epiglottitis–> presents with fever, stridor, and dyspnea

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13
Q

Hepatitis B virus is a _____ virus

replication sequence:

A

DNA;

double-stranded DNA–> +RNA template –> double-stranded DNA progeny

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14
Q

serum marks that would help confirm acute bacterial parotitis due to Staphylococcus aureus

A

elevated serum amylase level

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15
Q

most common laboratory abnormality seen with Legionella pneumonia that is different from other pneumonia is ______

A

hyponatremia

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16
Q

treatment of acute Corynbacterium diphtheriae requires administration of (in order of importance):

A

1) diphtheria antitoxin (passive immunization)
2) Penicillin or erythromycin
3) DPT vaccine (active immunization)

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17
Q

what is septic abortion and what (2) organisms may cause it?

A

any type of abortion resulting in infected retained products of conception in the uterine cavity

*Stapylococcus aureus and Escherichia coli

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18
Q

blastomyces dermatitidis

A

dimorphic fungus in tissue as round or oval yeasts with thick walls and broad-based bud!

  • endemic in SE USA
  • lung=primary site
  • skin and bone=major sites of dissmination
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19
Q

how do most enveloped nucleocapsid viruses acquire their lipid bilayer envelope?

exception to this?

A

by budding through the plasma membrane of the host cell

exception: herpesviruses— bud through ad acquire their envelope from the host cell nuclear membrane

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20
Q

what immune system process is needed to to eliminate intracellular organisms?

A

cell-mediated immunity

-immunocompromised, pregnancy, infants, elderlies are at risk of having serious infections from these organisms since they have compromised cell-mediated immunity

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21
Q

_____________ are normally present in human mouth and are major contributors to tooth decay and initiation of dental caries

A

viridans streptococci

  • can cause bacterial endocarditis, deep wound infections, ab abscesses, and septicemia
  • produce dextrans that aid them in colonizing host surfaces
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22
Q

______ is associated with bird and bat droppings in caves in Mississippi and Ohio River basins

A

Histoplasma capsulatum

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23
Q

______ = dimorphic fungus endemic to SW USA and exists in environment as mold (with hyphae) that forms spores that turn into spherules in lungs

A

Coccidioides immitis

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24
Q

alpha-amanitin, found in Amanita phalloides aka death cap mushroom) inhibits _________

A

RNA polymerase II (halting mRNA synthesis)

*cause severe hepatotoxicity

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25
Q

how can tertiary syphilis result in thoracic aortic aneurysm?

A

vasa vasorum endarteritis and oblitertion–> inflammation, ischemia, and weakening of adventitia

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26
Q

why add clavulanic acid to amoxicillin?

A

to decrease amoxicillin cleavage by bacterial cells

*clavulanic acid is a beta-lactamase inhibitor–>so when combined with a beta-lactamase susceptible antibiotic allows it to retain efficacy against the bacterium

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27
Q

adenovirus

A

caused by double-stranded DNA genome transmitted via direct contact, fecal-oral route or respiratory droplets

self-limiting

actue onset of fever, cough, congestion, pharyngitis, and conjunctivitis

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28
Q

what are transposons

A

mobile genetic elements that can mediate DNA transfer from plasmids to a bacterial chromosome, move genetic material from one position to another along a bacterial chromosome, or transfer genes from a bacterial chromosome to a plasmid

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29
Q

how does nonvirulent strains of S pneumoniae that do not form a capsule can acquire the genes that code fo the capsule and therefore gain virulence?

A

through a process called transformation (allows bacterium to take up exogenous DNA fragments and integrate them into its genome)

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30
Q

Aedes aegypti mosquitoes can transmit viruses that cause _____ and ______ (and their symptoms?)

A

dengue fever; chikungunya

DF: acute febrile illness with headaches, retro-orbital pain, and joint and muscle pain

Chikungunya: febrile illness with flulike symptoms, polyarthralgias, and diffuse macular rash

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31
Q

treatment for trichomonas vaginitis and bacterial vaginosis

A

metronidazole (disulfiram-like reaction after alcohol consumption)

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32
Q

how does lipid A from lipopolysaccharide of gram-negative baceria’s outer membrane induces endotoxic septic shock

A

activation of macrophages and granulocytes

  • -> synthesis of endogenous pyrogens (IL-1, prostaglandins, and inflammatory mediators
  • ->symptoms of septic shock
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33
Q

what is lipid A

A

region of the lipopolysaccharide (LPS) that makes up the outer membrane of gram-negative bacteria.
(toxic component of LPS)

endotoxin: found in the outer membrane

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34
Q

parvovirus B19 replicates in ______ (cell type) precursors in the _________

A

erythrocyte; bone marrow

erythema infectiosum, slapped-cheek rash

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35
Q

HSV infection can be diagnosed using

A

PCR, direct fluorescence antibody, viral culture (low sensitivity), or Tzanck smear (showing multinucleated giant cells)

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36
Q

clinical findings of Epstein-Barr virus induced mononucleosis

A

fever, profound fatique, lymphadenopathy, lymphocytosis, splenomegaly

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37
Q

first line therapy for Lyme disease

A

doxycycline (a tetracycline)

teratogen– cause teeth staining and also contraindicated in kids age <8

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38
Q

in HIV replication cycle, only the _____ (gag, pol, and env) polyprotein product is glycosylated to _______ and proteolytically cleaved to form _____ and _____

A

env; gp160; gp120; gp41

gp120 and gp41 work together to help the virus attach by binding to the CD4 receptor of cells

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39
Q

HSV infection can be diagnosed using

A

PCR, direct fluorescence antibody, viral culture (low sensitivity), or Tzanck smear (showing multinucleated giant cells)

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40
Q

how comes vaccination against Neisseria gonorrhoeae is hard to do?

A

Gonococci use their pili to adhere to mucosal epithelium

use antigenic variation to modify the pilus protein to avoid host defneses

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41
Q

acute bacterial arthritis in sexually active young adults is commonly caused by

A

Neisseria gonorrhoeae

associated with disseminated gonococcal infection that leads to septic arthritis

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42
Q

Echinococcus granulosus

A
  • most common cause of hydatid cysts (“eggshell calcification”) in liver
  • spilling of cyst contents–> anaphylactic shock
  • from dog and sheep
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43
Q

_____ and ______ act by ribosylating and inactivating elongation factor-2, inhibiting host cell protein synthesis and causing cell death

A

Diphetheria toxin; pseudomonal exotoxin A

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44
Q

most important virulence factor that uropathogenic E coli express

A

P fimbriae

without it, E coli can’t bind to uroepithelial cells

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45
Q

clinical presentation of tertiary syphilis

A

cardiovascular involvement and gummas (neurosyphilis can occur at any stage of infection)

gummas= necrotizing granulomas on skin, mucosa, subcutaneous tissue, and bones and within other organs

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46
Q

STD that is initially characterized by painless ulcers with later progression to painful inguinal lymphadenopathy (“buboes”) and ulceration

A

Chlamydia trachomatis

its inclusion bodies can be seen in host cell cytoplasm

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47
Q

Zidovudine (AZT)

A

nucleoside reverse transcriptase inhibitor used to treat HIV infection–> make 3’-5’ phosphodiester bond formation impossible

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48
Q

______, _______, and ______ are able to disrupt the peptidoglycan cell wall of gram-positive and gram-negative organisms

A

penicillins, cephalosporins, and vancomycin

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49
Q

if meningitis due to Neisseria meningitidis (what is the gram and shape), would antibiotic chemoprophylaxis be indicated?

A

YES-rifampin

-negative diplococcci (cocci in pairs)

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50
Q

what is the most common outcome in HBV-infected adults

A

> 95% get acute hepatitis with mild or subclinical symptoms that eventually completely resolve

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51
Q

trimethoprim, methotrexate, and pyrimethamine inhibit

A

dihydrofolate reductase (DHFR)

  • trimthoprim-restricts bacterial growth through DHFR
  • methotrexate targets rapidly proliferating human cells by halting DNA synthesis through DHFR
  • Pyrimethamine treat malaria and toxoplasmosis by inhibiting parasitic DHFR
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52
Q

pelvic inflammatory disease

A

frequently caused by Neisseria gonorrhoeae and Chlamydia trachomatis

  • if severe or untreated–> fallopian tube scarring–> infertility
  • treat with both 3rd gen cephalosporin and azithromycin or doxycycline
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53
Q

mucormycosis

A

infection due to Rhizopus, Mucor, and Absidia species

paranasal sinus involvement in a diabetic or immunosuppressed patient

irregular, broad nonseptate hyphae that branch at right angles

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54
Q

description of Streptococcus pyogenes (Group A streptococci)

A

gram-positive cocci in chains, catalase-negative, beta-hemolytic, pyrrolidonyl arylamidase positive (PYR-positive)

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55
Q

Secretory IgA’s purpose on mucosal surfaces

A

bind and inhibit the action of pili and other cell surface antigens involved in bacterial adherence to mucosa–> inhibit mucosal colonization by microorganism

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56
Q

treatment of cryptococcal meningitis

A

amphotericin B and flucytosine, followed by long-term fluconazole

57
Q

Actinomyces israelii

A
  • gram positive
  • normal oral, GI, and reproductive flora
  • cause oral/facial abscesses

*treat with long-term penicillin and surgical debridement

58
Q

causative agent of syphilis

A

treponema pallidum

*spiral-shaped gram negative spirochete
use darkfield microscopy from a lesion to diagnose

59
Q

HaEMOPhilus influenzae causes

A

Epiglottitis
Meningitis
Otitis media
Pneumonia

60
Q

spores from Clostridium perfringens cause

A

food poisoning–> transient watery diarrhea

also cause clostridial myonecrosis (gas gangrene)

61
Q

azoles mechanism of action

A

antifungal meds

Inhibit fungal sterol (ergosterol) synthesis by inhibiting the cytochrome P-450 enzyme that converts lanosterol to ergosterol.

62
Q

neuroimagining of a patient iwth herpes simplex virus (HSV) encephalitis

A

abnormal MRI signal in the bilateral temporal lobes

63
Q

mechanism of action of acyclovir

A

nucleoside analog that , once activated (monophosphorylate with viral thymidine kinase), competes with deoxyguanosine triphosphate for viral DNA polymerase to terminate viral DNA synthesis

64
Q

Listeria monocytogenes is characterized by what symptoms and who gets affects

A
  • gastroenteritis, septicemia, and meningoencephalitis
  • neonatal meningitis
  • patients with depressed cell-mediated immunity
65
Q

outbreaks of infection associated with dairy products, raw fruits and vegetabes and processed meats

A

Listeria monocytogenes

66
Q

neoplasm of endothelial cells seen in HIV/AIDS and transplant patients

A

Kaposi’s sarcoma

  • can affect GI, skin, and lungs
  • reddish/violet maculopapular lesions to raised hemorrhagic nodules or polypoid masses
  • biopsy show spindle cells, neovascularization, and extravasated RBC
67
Q

symptoms of typhoid fever from Salmonella Typhi

A

fever with relative bradycardia, watery diarrhea OR constipation, ab pain, salmon-colored rose spots on chest/ab, hemorrhagic enteritis with possible bowel perforation

68
Q

host defense (2 immune system components) against Candida

A

1) T lymphocytes–prevent superifical Candida infection

2) Neutrophils- prevent hematogenous spread of Candida

69
Q

Asymptomatic colonization of the ________________ is the most commonly MRSA-populated site in staff members

A

anterior nares or the nasopharynx

70
Q

Parvovirus B19 can cause ___________ in pregnant women

A

hydrops fetalis

71
Q

organisms that cause impetigo

A
  • Staphylococcus aureus (most common)

* group A streptococcus (S pyogenes)

72
Q

acute skin infections following dog bite associated with what organism

A 
*Pasteurella multocida (mouse-like odor;
can also happen with cat bite)
*staphylococci
*streptococci
*Capnocytophaga canimorsus
73
Q

light microscopy of Candida fungi

A

budding yeasts (single cells) with pseudohyphae

74
Q

mechanism most likely responsible for the antiseptic properties of alcohols (isopropanol, ethanol)

A

disruption of cell membranes; denaturation of proteins

75
Q

what is needed to convert acyclovir to active form

A

monophosphorylation of acyclovir by a viral thymidine kinase (first and rate-limiting step)

more effective against herpes simplex virus and varicella zoster virus than cytomegalovirus and Epstein-Barr virus

76
Q

hepatitis E- who does it infect? is it bad?

A
  • occurs mainly in young and middle-aged adults living in Asia, sub-Saharan Africa, and Mexico
  • typically self-limited and not associated with chronic liver disease or carrier state
  • high mortality rate with infected pregnant omen
77
Q

septic shock - features

A

infection with hypotension, tachycardia, tachypnea, and elevated or decreased body temperature

78
Q

most important mediator of sepsis

A

tumor necrosis factor alpha (TNF-alpha)

-an acute phase cytokine produced by activated macrophages

79
Q

hepatitis E-characeristics of the virus

A

virus=unenveloped, single-stranded RNA spread through the fecal-oral route

80
Q

why use both chloroquine and primaquine for treating malaria?

A

chloroquine- treatment of choice of uncomplicated malaria

primaquine` added with infection with P vivax and P ovale to eradicate the intrahepatic stages , which are responsible for relapses of malari

81
Q

human herpesvirus 6 (HHV-6): clinical significance

A
  • cause roseola infantum
  • febrile seizures
  • high fever for several days followed by an erythematous maculopapular rash (starts on the trunk and spreads to face and extremities)
82
Q

common cause of seizures in patients from Central and South America

A

Neurocysticercosis cause by Taenia solium, the pork tapeworm

imaging would find cystic brain lesion

83
Q

mechanism of action of aminoglycosides

A

interfere with aminoacyl binding site on 30S ribosomal subunit

  • causes cell to misread mRNA–> can’t make protein
  • gain resistance by methylation of the aminoglycoside-binding portion of the ribosme
84
Q

Clostridium tetani toxin mechanism of action

A

inhibit release of inhibitory neurotransmitters (GABA and glycine) from Renshaw cells in spinal cord

85
Q

Clostridium tetani: how does the toxin travel in the body to cause problems

A

wound–> motor neuron axons–> spinal cord

86
Q

Clostridium tetani- symptoms

A

Causes spastic paralysis, trismus (lockjaw), risus sardonicus (raised eyebrows and open grin), opisthotonos (spasms of spinal extensors)

87
Q

areas of the face affected by cavernous sinus thrombosis

A

contiguous spread of an infection from the medial third of the face, sinuses (ethmoidal or sphenoidal) or teeth and ocular muccle

commonly caused by Staph aureus and streptococci

88
Q

cysteine-tellurite agar used for

A

Corynebacterium diphtheriae, colonies are black in color, bacterium produces intracellular polyphosphate granules (metachromatic granules) detected with methylene blue staining

89
Q

MacConkey agar used for

A

to grow enteric bacteria

bile salt-containing agar that restricts the growth of most Gram positive organisms

90
Q

Q fever-what is it caused by?

A

zoonosis caused by Coxiella burnetti

inhalation of bacteria from air contaminated by animal waste (cattle/sheep amniotic fluid)

91
Q

symptoms of Q fever

A

febrile illness (fever, fatigue, and myalgias), headaches (retroorbital and photophobia), pneumonia, normal keukocyte count, thrombocytopenia, increased liver enzymes

92
Q

symptoms of trichomonas vaginalis

females vs males

A

female: vaginal burning, itching, urinary discomfort, and yellor/green vaginal discharge
male: urethritis… often aysymptomatic

93
Q

what is Trichomonas vaginalis?

how to diagnose?

A

motile, flagellated protozoan; causes STI

saline microscopy (wet mount) of the discharge

94
Q

protein A of Staphylococcus aureus

A
  • virulence factor that forms part of the outer peptidoglycan layer
  • binds Fc portion of IgG antibodies at complement-binding site, preventing complement activation
  • prevent opsonization and phagocytosis
95
Q

amphotericin B mechanism of action

A

binds the ergosterol of fungal cell membranes–> fungal cell lysis

binds to cholesterol too–> adverse effects (nephrotoxicity, hypokalemia, and hpomagesemia)

96
Q

peniciillin and cephalosporin mechanism of action

A
  • irreversibly binding to penicillin-binding proteins such as transpeptidases
  • Block transpeptidase cross-linking of peptidoglycan in cell wall.
  • Activate autolytic enzymes.
97
Q

patients with CD4+ counts <50 cells/u should be administered prophylactic_________ to prevent mycobacterium avium complex (MAC)

A

azithromycin

98
Q

HSV-1 and other herpesviruses are _________ and possess _______ genomes

A

enveloped; double-stranded DNA genomes

99
Q

side effects of protease inhibitors (HIV antiretroviral meds)

A

hyperglycemia, lipodystrophy, and drug-drug interactions due to inhibition of cytochrome P450

100
Q

mechanism of action- integrase inhibitor for antiviral therapy

A

disrupts HIV genome integration, prevent synthesis of viral mRNA

101
Q

mechanism of action of isoniazid (INH)

A

inhibition of mycolic acid synthesis

need bacterial catalase peroxidase to convert to active form

102
Q

mechanism of action of foscarnet

A
  • Viral DNA/RNA polymerase inhibitor and HIV reverse transcriptase inhibitor. Binds to pyrophosphate-binding site of enzyme. Does not require any kinase activation.
  • directly inhibits both DNA polymerase in herpesvirus and reverse transcriptase in HIV
  • have to be given IV
103
Q

Neisseria can be isolated by culture on __________ media such as the Thayer-martin VCN (vancomycin/colistin/nystatin) medium, which inhibits growth of contaminmants

A

selective

104
Q

human papillomavirus- mechanism of action

A

integrate into the host genome and produce viral proteins E6 and E7–> interact with cell cycle regulatory proteins p53 and Rb, respectively
–> inhibit cell cycle regulation and evade of apoptosis

105
Q

function of protein M of Streptococcus pyogenes

A
  • inhibit phagocytosis and the activation of complement
  • cytotoxic for neutrophils in serum and a mediator of bacterial attachment
  • the target of type-specific humoral immunity to S. pyogenes
106
Q

HBsAg

A

antigen found on surface of HBV; indicates hepatitis B infection

107
Q

Anti-HBs

A

antibody to HBsAg; immunity due to vaccination or recover to hepatitis B

108
Q

HBcAg

A

antigen associated with core of HBV

109
Q

Anti-HBc

A

if IgM=acute/recent infection

IgG=prior exposure or chronic infection

110
Q

HBeAg

A

indicates active viral replication and therefore high transmissibility and poorer prognosis

111
Q

anti-HBe

A

indicates low transmissibility

112
Q

ether and other organic solvents ______ the lipid bilayer that makes up the outer viral envelope

A

dissolve

–> loss of infectivity after exposure

113
Q

mechanism of action of echinocandins (eg, caspofungin, micafungin)

A

antifungal medications that inhibit synthesis of polysaccharide glucan, an essential component of the fungal cell wall

114
Q

side effect of ethambutol

A

optic neuropathy–> color blindness, central scotoma, and decreased visual acuity

reversible with discontinuation of drug

used to treat tuberculosis (RIPE-4 drug regimen)

115
Q

allergic reaction to abacavir (nucleoside reverse transcriptase inhibitor used to treat HIV/AIDS is strongly associated with _______

A

HLA-B*57:01

this reaction is also called abacavir hypersensitivity reaction

116
Q

adverse effects of aminoglycoside

A

ototoxicity (hearing loss, tinnitus) and nephrotoxicity

117
Q

“fusion inhibitors” of antiretroviral medications

eg, enfuvirtide

A

drugs that selectively bind to the HIV transmembrane envelop protein gp41

*prevent conformational changes needed for viral membrane to fuse iwth the target cellular membrane

118
Q

extended-spectrum beta lactamases produced by gram- negative bacteria–>

A

resistance to cephalosporins, penicillins, and other beta-lactam antibiotics

genes transmitted through plasmid conjugation

119
Q

HPV tend to infect what type of epithelial cells

A

stratified squamous epithelium (anal canal, vagina, cervix, true vocal cords)

120
Q

Haemophilus influenzae

(description of the bacteria, and what does it need to grow

A

gram-negative coccobacillus that requires oth X factor (hematin) and V factor (NAD+) to grow

121
Q

what do IL-12 do?

A

stimulates the differentiation of “naive” T-helper cells into TH1

if deficient in IL-12–> won’t make IFN-gamma necessary for macrophages activation–> treated with IFN-gamma administration

122
Q

what causes green discoloration of sputum during common bacterial infections?

A

presence of myeloperoxidase, a blue-green heme-based enzyme that is released from neutrophil azurophilic granules and forms hypochlorous acid (bleach)

123
Q

acid-fast stain= the steps and what happens to those that are acid-fast

A
  • apply aniline dye (eg, carbolfuchsin) to a smear and then decolorize with acid alcohol t
  • Mycobacterium and Nocardia (weakly)= acid fast
124
Q

sensitized TH2 cells secrete _____ and _____ and ______

A

IL-4; IL-13; IL-5

IL-4 and IL-13: promote B-lymphocyte class switching for IgE synethesis

IL-5: activates eosinophils and promotes IgA synthesis

125
Q

why can’t Legionella pneumophila be detected on Gram stain

A

it is a gram-negative rod with a unique lipopolysaccharide chains on the outer membrane inhibiting the staining

126
Q

what bugs can cause hepatic abscesses and how?

A

staph aureus- hematogenous seeding of the liver

enteric bacteria (e. coli, klebsiella, and enterococci)- ascend the bilitary tract, portal vein pyemia, or direct invasion from an adjacent area

127
Q

mechanism of action of oseltamivir (Tamiflu)

A

neuraminidase inhibitor–> so block release of virus form infected cells

need to given within 48 hours of the onset of symptoms

128
Q

which hepatitis virus is associated with hepatocellular carcinoma

A

B

129
Q

side effect of isoniazid

A

heaptotoxicity, P-450 inhibition, drug-induced SLE, vitamin B6 deficiency, anion gap metabolic acidosis

130
Q

what can be used as treatment of measles infection by reducing comorbidities, recovery time, and length of hospital?

A

vitamin A

131
Q

why would proton pump inhibitor (omeprazole) increase the risk of getting Vibrio cholerae

A

vibrio cholerae is very sensitive to gastric acidity

so decreased gastric acid makes it easier for the infection to take place

132
Q

how can Corynebacterium diphtheriae acquire virulence

A

via exotoxin encoded by beta-prophage

via bacteriophage-mediated “infection” with the Tox gene

133
Q

daptomycin: mechanism, use, and adverse effects

A

lipopeptide antibiotic that disrupts cell membranes of gram positive coccid by creating transmembrane channels

for S. aureus skin infection

myopathy, rhabdomyolysis (increased creatine phosphokinase)

134
Q

treatment for gonorrhea

A

ceftriaxone and azithromycin (a macrolide)

135
Q

what is ganciclovir used for

A

antibiotic against cytomegalovirus- inhibit viral DNA polymerase

136
Q

what type of virus can act as mRNA capable of using the host’s intracellular machinery for tranlation

A

purified RNA molecule that is single-stranded (SS) and positive (+) sense

137
Q

treatment for oropharyngeal candidiasis in those who don’t have advanced immuodeficiency

A

nystatin- polyene antifungal and drug of choice for oropharyngeal candidiasis

bind to ergosterol in fungal cell membrane–> form pores and leakage of cell contents

nystatin not absorbed in GI and is administered as oral “swish and swallow” agent

138
Q

what bacteria causes necrotizing fasciitis

A

Streptococcus pyogenes (group A strep)

139
Q

lyme disease can be treated with doxycycline or

A

penicillin-type antibiotics such as cefriaxone

UWorld Journal (18 decks)

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