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1
Q

What is the toxic component of LPS?

A

Lipid A

2
Q

What does the pilus/fimbria do and give an example

A

Mediates adherence of bacteria to cell surface as in meningococcus colonizing the pharyngeal surface

3
Q

Bacteria with unusual cell membranes/walls

A

Mycoplasma - membrane contains sterols, no cell wall. Mycobacteria - contain mycolic acid, high lipid content

4
Q

Bugs that do not gram stain well

A

These Rascals May Microscopically Lack Color. Treponema, Rickettsia, Mycobacteria, Mycoplasma, Legionella, Chlamydia

5
Q

Stain for legionella

A

Silver stain

6
Q

Organisms seen with giemsa stain

A

Borrelia, plasmodium, trypanosomes, chlamydia

7
Q

Organisms seen with PAS stain

A

Stains glycogen and mucopolysaccharides. Use to diagnose Whipples disease

8
Q

Organisms seen with silver stain

A

Fungi and legionella

9
Q

Culture requirements of h flu

A

Chocolate agar. Factor V (NAD) and Factor X (hematin). If grown with staph they will provide the needed NAD

10
Q

Culture requirements of n gonorrhoeae

A

Thayer-Martin (VPN). Vancomycin, Polymyxin, Nystatin. Or Vanco, Colistin, Nystatin, Trimethoprim

11
Q

Culture requirements of b pertussis

A

Bordet-Gengou (potato) agar

12
Q

Culture requirements of c diphtheriae

A

Tellurite plate, Lofflers media

13
Q

Culture requirements of m tb

A

Lowenstein-Jensen agar

14
Q

Culture requirements of m pneumoniae

A

Eatons agar

15
Q

Culture requirements of lactose-fermenting enterics

A

Will be pink on MacConkey. E coli also grown on Eosin-Methylene Blue (EMB) and will be green with metallic sheen

16
Q

Culture requirements of legionella

A

Charcoal yeast extract agar buffered with cysteine and iron

17
Q

Culture requirements of fungi

A

Sabourauds agar

18
Q

What is another name for polymixin?

A

Colistin

19
Q

What allows e coli to spread hematogenously and cause meningitis?

A

K-1 capsule

20
Q

Encapsulated bacteria (6)

A

Strep pneumo, H flu type b, N meningitidis, Salmonella, Klebsiella, group B strep

21
Q

What vaccines should you give an asplenic patient?

A

S pneumo, H flu, N meningitidis

22
Q

Test of choice for encapsulated bacteria

A

Quellung (will see capsular swelling)

23
Q

Catalase-positive organisms (5)

A

S aureus, Serratia, Pseudomonas, Candida, E coli

24
Q

What is the antigen in the N meningitidis vaccine?

A

Capsular polysaccharide

25
Q

Urease positive bugs (8)

A

Proteus, Ureaplasma, Nocardia, Cryptococcus, H pylori, Klebsiella, Staph saprophyticus, Staph epidermis

26
Q

Protein A virulence factor

A

Staph aureus. Binds Fc of Ig. Prevents opsonization and phagocytosis

27
Q

IgA protease

A

Cleaves IgA. Secreted by s. pneumoniae, h flu type b, and neisseria

28
Q

M protein

A

Group A streptococcus. Helps prevent phagocytosis

29
Q

Where are exotoxin and endotoxin genes respectively located?

A

Exotoxins - plasmid or bacteriophage, endotoxin - bacterial chromosome (remember that endotoxins are part of bacterial wall, thus part of bacteria themselves. Similarly the gene is in with bacterial genes)

30
Q

Heat stability of exotoxins and endotoxins respectively

A

Exotoxins destroyed rapidly at 60 C (except staph enterotoxin), endotoxins stable at 100 C for 1 hour

31
Q

Diseases caused by exotoxins and endotoxins respectively

A

Exotoxins - tetanus, botulism, diphtheria. Endotoxins - meningococcemia, gram negative sepsis

32
Q

Diphtheria toxin

A

Inactivates EF-2 and thus inhibits protein synthesis

33
Q

Exotoxin A

A

Pseudomonas. Inactivates EF-2 (like diphtheriae toxin) and thus inhibits protein synthesis

34
Q

Shiga Toxin

A

Shigella. Inactivates 60S ribosome by cleaving rRNA (like EHEC toxin). Causes GI mucosal damage and triggers HUS

35
Q

Shiga-like Toxin

A

EHEC (including O157H7). Inactivates 60S ribosome by cleaving rRNA. Enhances cytokine release, causes HUS but EHEC does not invade host cells (unlike shigella)

36
Q

What are the properties of EHEC in culture?

A

Does not ferment sorbitol, does not produce glucuronidase

37
Q

Heat-labile (cholera-like) toxin

A

ETEC. Overactivates adenylate cyclase increasing Cl secretion. Watery diarrhea.

38
Q

Heat-stable diarrhea

A

ETEC and Yersinia enterocolitica. Overactivates guanylate cyclase. Decreases reabsorption of NaCl and water in gut. Watery diarrhea in ETEC, bloody in y entocolitica (invades)

39
Q

Edema factor

A

Bacillus anthracis. Mimics adenylate cyclase (similar to pertussis toxin). Black eschar of cutaneous anthrax

40
Q

Cholera toxin

A

Vibrio cholerae. Overactivates adenylate cyclase by permanently activating Gs. Increased Cl secretion. Rice-water diarrhea

41
Q

Pertussis toxin

A

Bordatella pertussis. Overactivates adenylate cyclase by disabling Gi. Impairs phagocytosis.

42
Q

Tetanospasmin

A

Clostridium tetani. Cleaves SNARE (required for NT release). Prevents release of inhibitory NTs in spinal cord (GABA and glycine). Rigidity and lockjaw

43
Q

Botulinum toxin

A

Clostridium botulinum. Cleaves SNARE (required for NT release). Prevents stimulatory (Ach) signals at neuromuscular junction. Flaccid paralysis

44
Q

Botulinum toxin

A

Clostridium botulinum. Cleaves SNARE (required for NT release). Prevents stimulatory (Ach) signals at neuromuscular junction. Flaccid paralysis

45
Q

Alpha toxin

A

Clostridium perfringens. A phospholipase that degrades tissue and cell membranes. Causes gas gangrene and hemolysis

46
Q

Streptolysin O

A

Strep pyogenes. Protein that degrades cell membranes. Lyses RBCs (beta hemolysis). Use ASO in diagnosis of rheumatic fever

47
Q

Exotoxin A

A

Strep pyogenes. Superantigen (MHC 2 and TCR linking). Toxic shock syndrome

48
Q

Toxic shock syndrome toxin (TSST-1)

A

Staph aureus. Superantigen (MHC 2 and TCR linking). Toxic shock syndrome

49
Q

Transformation (including bacteria capable of it)

A

Ability to take up DNA from environment. Strep pneumo, h flu type b, neisseria

50
Q

Conjugation

A

F+ to F- (plasmid DNA only) or Hfr to F- (plasmid and chromosomal genes)

51
Q

Transposition

A

Transfer of genes between plasmids or between chromosome and plasmid. Plasmid DNA may then move between bacteria

52
Q

Generalized transduction

A

Lytic phage infection with accidental packing of bacterial chromosome into viral capsid. Viral transfer

53
Q

Specialized transduction

A

Lysogenic phage incorporates and takes bacterial DNA with it when it excises

54
Q

What toxins are encoded in lysogenic phages (specialized transduction)?

A

Shiga-like toxin, Botulinum toxin, Cholera toxin, Diphtheria toxin, Erythrogenic toxin of strep pyogenes

55
Q

Branching gram positive bacteria and what separates them

A

Actinomyces (anaerobe and not acid fast), Nocardia (aerobe, acid fast)

56
Q

Catalase positive and negative gram positive cocci

A

Positive - Staph (clusters), Negative - Strep (chains)

57
Q

Coagulase positive, catalase positive gram positive cocci

A

S aureus (beta hemolytic)

58
Q

Coagulase negative, catalase positive, gram positive cocci

A

Novobiocin sensitive - staph epidermis, novobiocin resistant - staph saprophyticus

59
Q

What do staph epidermis tend to infect?

A

Teflon coated surfaces (due to biofilm formation) such as IVs and other artifical surfaces

60
Q

Alpha hemolytic catalase negative gram positive cocci

A

Optochin sensitive - strep pneumo (bile soluble - does not grow in bile). Optochin resistant - Viridans strep (eg strep mutans, insuluble in bile)

61
Q

Beta hemolytic catalase negative gram positive cocci

A

Group A (Bacitracin sensitive) - Strep pyogenes (impetigo). Group B (bacitracin resistant) - Strep agalactiae

62
Q

Gamma hemolytic catalase negative gram positive cocci

A

Enterococci (e faecalis) - grow in 6.5 pct NaCl and bile. Nonentercocci (strep bovis) - grow in bile but not 6.5 pct NaCl

63
Q

Gram positive mnemonics

A

Staph (novobiocin) - On offices STAPH retreat there was NO StRES. Strep (optochin) - OVRPS. Strep (bacitracin) - B-BRAS

64
Q

Hemolysis of listeria monocytogenes

A

Beta

65
Q

What is the most common site of staph aureus colonization?

A

Anterior nares

66
Q

What is strep pneumo the most common cause of?

A

Meningitis, Otitis media in children, Pneumonia, Sinusitis

67
Q

Color of sputum in strep pneumo infection

A

Rust colored

68
Q

Strep viridans infections

A

Dental caries (strep mutans), subacute bacterial endocarditis of damaged valves (strep sanguis)

69
Q

What infection precipitates rheumatic fever?

A

Group A strep (strep pyogenes)

70
Q

What is done to prevent group B strep infection in newborns?

A

Pregnant women screened at 35-37 weeks. Positive patients receive intrapartum penicillin

71
Q

What do enterococci cause?

A

UTI and subacute endocarditis. Are normal colonic flora. Are penicillin G resistant

72
Q

Strep bovis

A

Normal gut bacteria. Can cause bacteremia and subacute endocarditis in colon cancer patients

73
Q

Gram positive rods with metachromatic (blue and red) granules and Elek test for toxin

A

Cornyebacterium diptheriae

74
Q

Gram positive rods with metachromatic (blue and red) granules and Elek test for toxin

A

Cornyebacterium diptheriae

75
Q

What is seen in diphtheriae pharyngitis

A

Grayish-white pseudomembrane and lymphadenopathy

76
Q

What is needed to prevent clostridium tetani infection and what is the implication of this?

A

IgG. Breastmilk will not cut it. Vaccinate early

77
Q

Path tetanospasmin travels

A

Wound to motor neuron axon to spinal cord

78
Q

Toxin A and Toxin B

A

C difficile. A (enterotoxin) - binds brush border of gut. B (cytotoxin) - destroys enterocyte cytoskeleton, causing pseudomembranous colitis

79
Q

How do you diagnose C difficile colitis?

A

Detection of Toxin A and/or B in the stool

80
Q

Cause and treatment of C difficile

A

Commonly caused by clindamycin or ampicillin. Treat with metronidazole or oral vanco

81
Q

What is given to prevent neonatal tetanus?

A

A maternal vaccine during pregnancy

82
Q

Only bacterium with a polypeptide capsule (contains D-glutamate)

A

Bacillus anthracis

83
Q

Fever, pulmonary hemorrhage, mediastinitis, shock

A

Pulmonary anthrax

84
Q

Microscopy of anthrax infection

A

Long chains (medussa head appearance)

85
Q

People in what profession are susceptible to anthrax infection?

A

Woolsorters

86
Q

Culture appearance of listeria monocytogenes

A

Narrow zone of beta hemolysis on sheep blood agar

87
Q

Where does listeria monocytogenes live?

A

Facultative intracellular

88
Q

Amnioitis, septicemia, and spontaneous abortion. Or granulomatosis infantiseptic. Or neonatal meningitis. Or meningitis in immunocompromise. Or mild gastroenteritis (healthy adult)

A

Listeria

89
Q

Treatment for listeria

A

Usually self-limited. Ampicillin in infants and immunocompromised

90
Q

Treatment for branching gram positive rods

A

SNAP. Sulfa for Nocardia, Actinomyces use Penicillin

91
Q

Prophylactic treatment for MAIC in AIDS patients

A

Azithromycin

92
Q

Fevers, weight loss, weakness, hepatosplenomegaly

A

MAI

93
Q

Treatment for leprosy

A

Dapsone (toxicity is hemolysis and methemoglobinemia)

94
Q

Outcomes of leprosy

A

Lepromatous (Th2 response), tuberculoid (Th1 response)

95
Q

Gram negative cocci

A

Maltose fermenter - N meningitidis. Maltose nonfermenter - N gonorrhoeae

96
Q

Gram negative coccoid rods

A

H flu, pasteurella, brucella, bordatella pertussis

97
Q

Gram negative comma shaped (oxidase positive)

A

Grows at 42 C - campylobacter jejuni. Grows in alkaline media - vibriocholerae

98
Q

Gram negative lactose fermenting rods

A

Fast fermenters - klebsiella, e coli, enterobacter. Slow fermenters - citrobacter, serratia, others

99
Q

Gram negative non lactose fermenting rods

A

Oxidase negative - shigella (no H2S production), salmonella and proteus (H2S production). Oxidase positive - pseudomonas

100
Q

Why dont you get lasting imunity from gonoccocal infection?

A

Due to rapid antigenic variation of pilus proteins (which is also why we dont have a vaccine)

101
Q

What does meningococcus cause?

A

Meningococcemia, meningitis, and Waterhouse-Friderichsen syndrome

102
Q

What does gonococcus cause?

A

Gonorrhea, septic arthritis, neonatal conjuctivitis, PID, and Fitz-Hugh-Curtis syndrome

103
Q

What does meningococcus have that is analogous to LPS of enteric gram negatives?

A

LOS

104
Q

Prophylaxis of meningococcus close contacts

A

Rifampin

105
Q

Treatment of gonococcus and meningococcus respectively

A

Gonococcus - cetriaxone, meningococcus - ceftriaxone or penicillin G

106
Q

What does h flu cause?

A

Epiglottitis (cherry red), Meningitis, Otitis media, and Pneumonia

107
Q

Transmission of h flu

A

Aerosol

108
Q

Treatment and prophylaxis for h flu

A

Ceftriaxone (treatment) and rifampin (close contact prophylaxis)

109
Q

What is contained in the HiB vaccine?

A

PRP component of the HiB capsule conjugated to diphtheria toxoid (give between 2 and 18 months of age)

110
Q

Test of choice for legionella

A

Urine assay for antigen

111
Q

Transmission and habitat of legionella

A

Aerosol. Water source habitat

112
Q

Treatment for legionella

A

Erythromycin

113
Q

What presentation in a pneumonia case would suggest legionella over strep pneumo?

A

Pneumonia + GI + Neuro symptoms

114
Q

High fever in smoker with diarrhea, confusion, cough, and chest pain

A

Legionella

115
Q

Erythema gangrenosum

A

Necrotic skin condition due to pseudomonas exotoxin

116
Q

What is pseudomonas associated with

A

Wound and burn infection, pneumonia (esp in CF), sepsis (black lesions on skin), swimmers ear, UTI, drug users and diabetic osteomyelitis, hot tub folliculitis, malignant otitis externa in diabetics

117
Q

Smell of pseudomonas

A

Grape like odor

118
Q

Treatment for pseudomonas

A

Aminoglycoside plus extended-spectrum penicillin (piperacillin, ticarcillin)

119
Q

Most important virulence factor in e coli UTI

A

Fimbriae

120
Q

E coli diarrhea in children

A

EPEC

121
Q

Which e coli does not ferment sorbitol?

A

EHEC

122
Q

Red currant jelly sputum

A

Klebsiella

123
Q

Contrast DIC with TTP-HUS

A

1) Pts bleed in DIC. 2) Only platelets activated in TTP-HUS. 3) PTT and PT prolonged in DIC, 4) Low fibrinogen and increased FDP in DIC

124
Q

Which populations are more common in TTP and HUS respectively

A

TTP - pts with mainly CNS symptoms. HUS - children with renal failure and mild CNS symptoms

125
Q

Main differences betweeon salmonella and shigella

A

Salmonella have flagella and can disseminate hematogenously and produce H2S

126
Q

What may prolong symptoms in salmonella infection?

A

Antibiotics

127
Q

Rose spots on abdomen, fever, headache, diarrhea.

A

Salmonella typhi (typhoid fever). May remain in gallbladder in carrier state

128
Q

How do shigella enter our cells?

A

They first enter antigen sample M (microfold) cells, then spread to epithelial cells

129
Q

How do Shigella move?

A

Actin polymerization (they do not have flagella like salmonella do)

130
Q

Most common cause of bloody diarrhea

A

Campylobacter jejuni. This is especially true in children

131
Q

Transmission of campylobacter

A

Fecal-oral through poultry, meat, unpasturized milk

132
Q

Common antecedent to Guillain-Barre

A

Pet feces (puppies), contaminated milk, or pork

133
Q

Diarrhea outbreaks in day care centers. Can also cause mesenteric adenitis which can mimic Crohns or appendicits

A

Yersinia entercolitica

134
Q

Spirochetes

A

Borrelia, Leptospira, Treponema

135
Q

Flulike symptoms, jaundice, photophobia with conjunctivitis.

A

Leptospirosis. Found in water contaminated with animal urine, prevalent among surfers and in the tropics

136
Q

Severe jaundice and azotemia, fever, hemorrhage, anemia

A

Weils disease (icterohemorrhagic leptospirosis) - liver and kidney dysfuntcion from severe leptospira infection

137
Q

Stages of lyme disease

A

1 - erythema migrans, flulike symptoms. 2 - Bells palsy, AV nodal block. 3 - chronic monoarthritis and migratory polyarthritis

138
Q

Treatment for lyme

A

Doxycycline, ceftriaxone

139
Q

Stages of syphilis

A

1 - painless chancre, 2 - rash, condylomata lata. 3 - Gummas, aoritis, neurosyphilis, argyll-robertson pupil

140
Q

Saber shins, saddle nose, CN 8 deafness, Hutchinsons teeth, mulberry molars

A

Congenital syphilis

141
Q

Argyll-Robertson pupil

A

Reactive to accomodation but not light

142
Q

Causes of VDRL false positives

A

VDRL. Viruses (mono, hepatitis), Drugs, Rheumatic fever, Lupus and leprosy

143
Q

Histologic appearance of brucellosis and what is the source?

A

Chronic caseating granulomas similar to Tb endocarditis. Unpasteurized dairy (common in cattle ranchers)

144
Q

Source and organism of Q fever

A

Coxiella burnetii. Spores from tick feces and cattle placenta

145
Q

Source and organism of ehrlichiosis

A

Ehrlichiosis chaffeensis. Lone star tick

146
Q

Vector for francisella tularensis

A

Ticks, rabbits, deer fly

147
Q

Vector for pasteurella multocida

A

Animal bite, cats, dogs

148
Q

Organism and vector for epidemic typhys

A

Rickettsia prowazekii. Louse

149
Q

Vector and organism for endemic typhyus

A

Rickettsia typhi. Flease

150
Q

Characteristic finding in garnderella vaginalis infection

A

Fishy odor on addition of kOH

151
Q

What infection is associated with sexual activity but is not an STD?

A

Garnerella overgrowth

152
Q

Clue cells

A

Gardnerella overgrowth. Vaginal epithelial cells covered with bacteria

153
Q

Treatment for gardnerella

A

Metronidazole

154
Q

Where do Rickettsia live and what do they need to survive?

A

Intracellularly. Need CoA and NAD+

155
Q

Rash starting centrally and spreading out sparing palms and soles

A

Epidemic typhys. R prowazekii carried by human body louse

156
Q

Headache, fever, rash (vasculitis) starting on palms and soles

A

Rickettsia (but not typhus type. Typhus rash starts on trunk and spreads out)

157
Q

Rickettsial pneumonia with no rash, no vector, and negative Weil-Felix

A

Q fever (coxiella burnetti). Organism can survive outside for a long time

158
Q

Weil-Felix

A

Mixing pts serum with proteus antigens and antirickettsial antibodies will cross react with Proteus O antigen and agglutinate (if they have had a rickettsial infection)

159
Q

Rash on palms and soles migrating to wrist, ankles, then trunk, headache, fever

A

Rocky mountain spotted fever

160
Q

In what infections is palm and sole rash seen?

A

Coxsackie A (hand foot and mouth), RMSF, Syphilis

161
Q

Two main forms in chlamydia life cycle

A

Elementary body (infectious), and Reticulate body

162
Q

Lab diagnois of chlamydiae

A

Cytoplasmic inclusions on Giemsa or floresecent antibody stained smear

163
Q

Chlamydia trachomatis serotypes

A

ABC - blindness, africa, chronic. D-K - urethritis, PID, ectopic, neonatal pneumonia and conjunctivitis. L1L2L3 - Lymphogranuloma venerum

164
Q

Cause of atypical pnuemonia, high titer of cold aggultinins (IgM), grown on Eatons agar

A

Mycoplasma pneumoniae

165
Q

Treatment for mycoplasma pneumoniae

A

Tetracycline or erythromycin (do not use penicillins as they have no cell wall)

166
Q

Atypical pneumonia outbreak in military recruits or prisons

A

Mycoplasma pneumoniae

167
Q

Main fungus in New England and mid-atlantic

A

Blastomyces

168
Q

Main fungus in midwest

A

Histoplasma

169
Q

Main fungus in southwest

A

Coccidiodes

170
Q

Main fungus in latin america

A

Paracoccidiodes

171
Q

Symptoms of histoplasmosis

A

pneumonia

172
Q

Dimorphic fungus in bird or bat droppings

A

Histoplasmosis

173
Q

Treatment for systemic mycoses

A

Fluconazole or ketoconazole (local), amphotericin B (systemic)

174
Q

Dimorphic broad based buds

A

Blastomyces

175
Q

Symptoms of blastomycosis

A

Inflammatory lung disease, can disseminate to skin and bone. Granulomatous nodules

176
Q

Symptoms of coccidiodomycosis

A

Pneumonia and meningitis, can disseminate to bone and skin

177
Q

Dimorphic fungus which looks like a ball of grapes

A

Coccidiodes

178
Q

Which systemic mycoses can become a spherule filled with endospores (much larger than an RBC)?

A

Coccidiodes

179
Q

Dimorphic fungus with captains wheel appearance

A

Paracoccidiodes

180
Q

How does malassezia furfur affect skin pigment?

A

Degrades lipids, which produces acids that damage melanocytes and cause hypopigmentation or hyperpigmented patches

181
Q

What kind of weather is conducive to malassezia furfur?

A

Hot, humid weather

182
Q

Treatment for tinea versicolor

A

Topical miconazole, selenium sulfide

183
Q

Histologic appearance of malassezia furfur

A

Spaghetti and meatball look on KOH prep

184
Q

What cells are responsible for preventing candidiasis?

A

Th cells suppress superficial candidiasis. Neutrophils prevent hematogenous spread

185
Q

Forms of candida

A

Dimorphic. Psuedohyphae and budding at 20C, Germ tubes at 37C

186
Q

Treatment for candidiasis

A

Topical azole (vaginal), fluconazole or caspofungin (oral/esophageal), amphotericin B, fluconazole, caspofungin (systemic)

187
Q

Acute angle hyphae

A

Aspergillus

188
Q

How do aflatoxins cause cancer?

A

They cause a GC to TA mutation in p53

189
Q

Which opportunistic fungal infections are not dimorphic?

A

Aspergillus, cryptococcus, mucor and rhizopus (I think), PCP (I think)

190
Q

Histologic appearance of cryptococcus

A

Heavily encapsulated yeast. Little balls with smaller balls in them

191
Q

How is cryptococcus acquired?

A

Inhalation (which results in hematogenous dissemination) from yeast in soil and pigeon droppings

192
Q

Characteristic brain lesion from cryptococcus

A

Soap bubble lesions

193
Q

What patients tend to get mucor and rhizpus infections?

A

DKA pts and leukemia pts

194
Q

Headache, facial pain, black necrotic eschar on face, possible cranial nerve involvement

A

Mucor and rhizopus infections

195
Q

How is PCP acquired?

A

Inhalation of yeast

196
Q

Treatment for PCP

A

TMP-SMX, pentamidine, dapsone. Prophylax at CD4 less than 200

197
Q

Dimorphic, cigar-shaped budding yeast that lives on vegetation

A

Sporothrix schenkii

198
Q

Treatment for sporothrix schenkii

A

Itraconazole or KI

199
Q

Bloating, flatulence, foul-smelling fatty diarrhea in campers and hikers

A

Giardiasis

200
Q

How are giardia, entamoeba, and cryptosporidum respectively transmitted?

A

All are cysts in water

201
Q

Treatment for giardia

A

Metronidazole

202
Q

Treatment for entamoeba histolytica

A

Metronidazole and iodoquinol

203
Q

Treatment for cryptosporidium

A

Prevention (water treatment), nitazoxanide

204
Q

Bloody diarrhea, liver abscess, RUQ pain, flask-shaped colonic ulcers

A

Entamoeba

205
Q

Chorioretinitis, hydrocephalus, intracranial calcifications

A

Toxoplasmosis (usually in HIV)

206
Q

Transmission of toxoplasma

A

Cysts in meat or cat feces

207
Q

Treatment for toxoplasma

A

Sulfadiazine and pyrimethamine

208
Q

Rapidly fatal meningoencephalitis in someone who swam in a fresh water pool

A

Naegleria fowleri

209
Q

Where do you look for the amoeba in naegleria infection?

A

CSF

210
Q

Organism and vector for sleeping sickness

A

Trypanosoma brucei, gambiense, rhodesiense. Tsetse fly (painful bite)

211
Q

Treatment for sleeping sickness

A

Suramin (blood-borne), melarsoprol (CNS protection)

212
Q

Cycle length of the various malarias

A

Vivax/Ovale - 48 hours, Falciparum - irregular, Malariae - 72 hours

213
Q

Which malaria has a dormant form in the liver?

A

Vivax-ovale

214
Q

Which malaria causes cerebral malaria and how?

A

Falciparum. Parasitized RBCs occlude capillaries in brain (also kidney and lungs)

215
Q

Malaria treatment

A

Start with chloroquine (blocks plasmodium heme polymerase). If resistant, use mefloquine. Vivax/ovale - add primaquine for hypnozoites

216
Q

Fever and hemolytic anemia, northeastern United States, asplenia in severe disease

A

Babesia

217
Q

Treatment for babesia

A

Quinine, clindamycin

218
Q

Organism and vector in Chagas disease

A

Trypanosoma cruzi. Reduviid bug (kissing bug, painless bite)

219
Q

Treatment for Chagas disease

A

Nifurtimox

220
Q

Dilated cardiomyopathy, megacolon, megaesophagus

A

Chagas disease (mostly in S america)

221
Q

Spiking fevers, hepatosplenomegaly, pancytopenia

A

Visceral leishmaniasis

222
Q

Organism and vector of leishmaniasis

A

Leishmania donovani. Sandfly

223
Q

Treatment for leishmaniasis

A

Sodium stibogluconate

224
Q

Treatment for trichomonas vaginalis

A

Metronidazole (for patient and partner)

225
Q

Organism and treatment for pinworm

A

Enterobius vermicularis. Bendazoles or pyrantel pamoate

226
Q

Transmission of pinworm

A

Food contaminated with eggs

227
Q

Nematode that encysts in muscle, causes periorbital edema

A

Trichinella spiralis

228
Q

Nematode that penetrates the skin, causes vomiting, diarrhea, anemia

A

Strongyloides stercoralis

229
Q

Nematode that penetrates skin of feet, causes anemia

A

Ancylostoma duodenale and Necator americans (hookworms)

230
Q

Transmission and treatment of dracunculus medinensis

A

Drinking water, niridazole

231
Q

Loa Loa

A

Transmitted by deer flies, causing skin swelling. Treat with DEC

232
Q

Wuchereria bancrofti

A

Transmitted by female mosquito. Causes elephantiasis. Treat with DEC

233
Q

Toxocara canis

A

Food contaminated with eggs, causes granulomas (can cause blindness) and visceral larva migrans. Treat with DEC

234
Q

Treatment for taenia solium

A

Praziquantel (use bendazoles for neurocysticercosis)

235
Q

Appearance of t solium lesions in the brain

A

Swiss cheese appearance

236
Q

Treatment for diphyllobothrium latum

A

Praziquantel

237
Q

Cysts in the liver that can cause anaphylaxis if antigens are released during removal

A

Echinococcus granulosus. Acquired from eggs in dog feces. Treat with bendazoles

238
Q

Treatment for trematodes (flukes)

A

Praziquantel

239
Q

Trematodes (flukes) (3)

A

Schistosoma, clonorchis sinesis (pigmented gallstones, cholangiocarcinoma), paragonimus westermani (crab meat, hemoptysis)

240
Q

Routes of nematode infection and the worms that use each (6 total)

A

Ingestion - Enterobius, Ascaris, Trichinella. Cutaneous - Strongyloides, Ancylostoma, Necator

241
Q

Parasite of brain cysts and seizures

A

T solium

242
Q

Parasite of liver cysts

A

Echinococcus granulosus

243
Q

Parasite of B12 deficiency

A

Diphyllobothrium latum

244
Q

Parasite of biliary tract disease, cholangiocarcinoma

A

Clonorchis sinesis

245
Q

Parasite of hemotypsis

A

Paragonimus westermani

246
Q

Parasite of portal hypertension

A

Schistosoma mansoni

247
Q

Parasite of hematuria, bladder cancer

A

Schistosoma haematobium

248
Q

Parasite of microcytic anemia

A

Ancylostoma, necator

249
Q

Complementation and the requirement for it

A

When one virus uses another viruses protein product. Both viruses have to be infecting the same cell at the same time

250
Q

Phenotypic mixing

A

Coating of a progeny virus of virus A with surface proteins of virus B. Have to be infecting the same cell at the same time. Surface protein determines infectivity, but progeny carry virus A genetic material

251
Q

Live attenuated vaccines (5)

A

Lead to longer production of mucosal IgA than killed vaccines. Smallpox, yellow fever, chickenpox, Sabins polio, MMR

252
Q

Killed vaccines (4)

A

Rabies, influenza, salk polio, HAV

253
Q

Recombinant vaccines (2)

A

HBV, HPV

254
Q

All DNA viruses are what and what is the exception?

A

Double stranded, except the parvoviruses

255
Q

What are all RNA viruses and what is the exception?

A

Single stranded except Reoviruses

256
Q

RNA viruses

A

I went to a RETRO (retrovirus) TOGA (togavirus) party where I drank FLAVored (flavivirus) CORONA (coronavirus) and ate HIPPY (hepevirus) CALIfornia (Calcivirus) PICKLES (picornavirus)

257
Q

What naked viruses are infectious?

A

dsDNA (except pox and HBV) and +strand ssRNA

258
Q

Where do viruses replicate

A

DNA viruses - nucleus (except pox). RNA - cytoplasm (except influenza and retroviruses)

259
Q

Naked viruses (7)

A

Calcivirus, Picornavirus, Reovirus, Parvovirus, Adenovirus, Papilloma, Polyoma

260
Q

Which viruses acquire their envelops from nuclear membrane?

A

Herpesviruses (other get them from the PM)

261
Q

DNA viruses (7)

A

Hepadna, Herpes, Adenoa, Pox, Parvo, Papilloma, Polyoma

262
Q

All DNA viruses are icosehedral except which?

A

Pox (complex)

263
Q

HHV-6

A

Roseola (exanthem subitum)

264
Q

Which hepatitis virus is a DNA virus?

A

Hep B (it is a hepadnavirus)

265
Q

What virus is not a retrovirus but has reverse transcriptase?

A

HBV

266
Q

Most common viral cause of acute cystitis (dysuria, hematuria) in kids

A

Adenovirus

267
Q

Febrile pharyngitis, sore throat, acute hemorrhagic cystitis, pneumonia, conjunctivitis

A

Adenovirus

268
Q

Erythema infectiosum (fifth disease)

A

Parvo B19. Slapped cheek rash, hydrops fetalis in utero, RBC aplasia and RA-like symptoms in adults

269
Q

Causes of pure red cell aplasia

A

Parvo B19 and thymoma

270
Q

Histology of VZV infection

A

Intranuclear inclusions, multinucleate giant cells

271
Q

Tzanck test

A

Smear to detect HSV-1, HSV-2 and VZV

272
Q

Fever, hepatosplenomegaly, pharyngitis, lymphadenopathy (especially posterior cervical nodes). 15-20 years of age

A

Mononucleosis

273
Q

Family and symptomology of norwalk virus

A

Calcivirus. Viral gastroenteritis

274
Q

Which Hepatitis viruses are RNA viruses and what is the family of each?

A

HAV - Picorna, HCV - Flavi, HDV - Delta, HEV - Hepe

275
Q

Picornaviruses (5)

A

Polio, Echo (aseptic meningitis), Rhino, Coxsackie (aseptic meningitis, herpangina, febrile pharyngitis, hand foot mouth disease), HAV

276
Q

Paramyxoviruses (4)

A

Parinfluenza (croup), RSV (briochilitis in babies, treat with ribavirin), Rubeola (Measles), Mumps

277
Q

Negative stranded RNA viruses (6)

A

Always Bring Polymerase Or Fail Replication. Arenaviruses, Bunyaviruses, Paramyxoviruses, Orthomyxoviruses, Filoviruses, Rhabdoviruses

278
Q

Segmented viruses (4)

A

BOAR. All are RNA viruses. Bunyaviruses, Orthomyxoviruses, Arenaviruses, Reoviruses

279
Q

Protein synthesis in picornaviruses

A

RNA translated into 1 large polypeptide that is cleaved by proteases into functional viral proteins

280
Q

Spread of picornaviruses

A

Fecal oral (except rhinovirus)

281
Q

Why doesnt rhinovirus affect the GI tract?

A

It is acid labile

282
Q

High fever, black vomitus, jaundice

A

Yellow fever (a flavivirus)

283
Q

Diarrhea in day care centers due to villous destruction with atrophy. A segmented RNA virus.

A

Rotavirus (a reovirus)

284
Q

Fever, postauricular adenopathy, lymphadenopathy, arthralgias, fine truncal rash that starts at head and moves down.

A

Rubella (a togavirus, also called german measles). Mild in children but serious if congenital

285
Q

What do paramyxoviruses have, what does it do, and how does this relate to treatment?

A

F (fusion) protein. Causes respiratory epithelial cells to fuse and form multinucleated cells. Palivizumab is a monoclonal antibody against F protein

286
Q

Palivizumab

A

Monoclonal antibody against F protein (paramyxoviruses). Prevents pneumonia in premature infants

287
Q

Descending maculopapular rash including hands and feet, koplik spots.

A

Measles (rubeola, a paramyxovirus)

288
Q

Difference between the rashes in rubella and rubeola

A

Rubeola (measles) rash includes hands and feet. Rubella (german measles) rash stays on trunk. Both spread down from head

289
Q

Potential sequelae of measles (rubeola)

A

SSPE (many years later), encephalitis, giant cell pneumonia (typically only in immunosuppressed)

290
Q

Cough, cold like symptoms, conjunctivitis

A

Measles

291
Q

Parotitis, aseptic meningitis, orchitis

A

Mumps (a paramyxovirus)

292
Q

Between measles (rubeola) and german measles (rubella), which contains hemagglutinin?

A

Measles (rubeola), as it is a paramyxovirus

293
Q

Fever, malaise, agitation, photophobia, hydrophobia, paralysis, coma, death

A

Rabies (progresses in that order)

294
Q

Histology of hepatitis A infection

A

Hepatocyte ballooning degeneration and apoptosis

295
Q

Histology of Hep B infection

A

Fine, eosinophilic, cytoplasmic granules of HBsAg are visible, giving ground glass appearance

296
Q

Transmission of HBV

A

Parenteral, sexual, maternal-fetal

297
Q

Symptoms of HBV prodromal period

A

Serum-sickness like

298
Q

What viral hepatitises predispose to cancer and which cancer?

A

HCC. HBV and HCV

299
Q

Best test for active HAV infection

A

Anti-HAVAb (IgM)

300
Q

Best test for prior HAV infection

A

Anti-HAVAb (IgG). Can also indicate prior vaccination

301
Q

What Hep B serologic marker indicates high transmissibility?

A

HBeAg

302
Q

HIV structural genes

A

Env (gp120 for attachment, gp41 for fusion and entry), Gag (p24 capsid), Pol (reverse transcriptase)

303
Q

What receptors does HIV use for entry?

A

CXCR4 or CCR5 (CD4 cells), CCR5 and CD4 (macrophages)

304
Q

Why are HIV tests initially falsely positive in babies born to infected mothers?

A

Anti-GP120 crosses placenta

305
Q

Where does the HIV virus replicate during the latent phase?

A

Lymph nodes

306
Q

What fungal infection is commonly picked up by spelunkers?

A

Histoplasma capsulatum (from bats)

307
Q

Low-grade fever, cough, hepatosplenomegaly, tongue ulcer, only pulmonary symptoms if CD4 count greater than 100

A

Histoplasma

308
Q

Encephalopathy and demyelination in pt with CD4 count below 200

A

JC virus reactivation

309
Q

Ring-enhancing brain abscesses with CD4 count below 100

A

Toxoplasma

310
Q

CD4 count for cryptococcus meningitis

A

Below 50

311
Q

CD4 count for CMV retinitis

A

Below 50. Will see cotton-wool spots

312
Q

CD4 ranges for PCP and MAI infections respectively

A

PCP - below 200, MAI - below 50

313
Q

Bugs that can mimic appendicits (3)

A

Yersinia enterocolitica, campylobacter jejuni, non-typhoidal salmonella. Mimic appendicits by causing mesenteric adenitis

314
Q

Bugs causing bloody diarrhea (7)

A

Campylobacter, salmonella, shigella, EHEC, EIEC, Yersinia enterocolitica, Entamoeba histolytica

315
Q

Bugs causing watery diarrhea (4)

A

ETEC, Vibrio choleraea, C diff, C perfringens. Also protozoa - giardia, cryptosporidium, viruses - rota, adeno, norwalk

316
Q

Most common causes of pneumonia (in order with most common first) in neonates

A

Group B strep, E coli

317
Q

Most common causes of pneumonia (in order with most common first) in children 4 weeks to 18 years

A

Viruses (RSV), Mycoplasma, Chlamydia trachomatis, Strep pneumo

318
Q

Most common causes of pneumonia (in order with most common first) in adults (18-40)

A

Mycoplasma, C pneumoniae, Strep pneumo

319
Q

Most common causes of pneumonia (in order with most common first) in adults (40-65)

A

Strep pneumo, H flu, Anaerobes, Viruses, Mycoplasma

320
Q

Most common causes of pneumonia (in order with most common first) in elderly

A

Strep pneumo, Influenza, Anaerobes, H flu, Gram negative rods

321
Q

Most common causes of nosocomial pneumonia

A

Staph, enteric gram negative rods

322
Q

Most common causes of aspiration pneumonia and treatment

A

Anaerobes. Clindamycin

323
Q

Most common causes of pneumonia in alcoholics and IV drug users

A

Strep pneumo, Klebsiella, Staph

324
Q

Most common causes of pneumonia in CF

A

Pseudomonas

325
Q

Most common causes of atypical pneumonia

A

Mycoplasma, Legionella, Chlamydia

326
Q

CSF findings in bacterial meningitis

A

WBC high (over 1000) predominantely neutrophils. Glucose low (below 70), protein high

327
Q

Most common causes of meningitis (in order with most common first) in newborn

A

Group B strep, E Coli, Listeria

328
Q

Most common causes of meningitis (in order with most common first) in children (6 mos to 6 years)

A

Strep pneumo, N meningitidis, HiB, Enteroviruses

329
Q

Most common causes of meningitis (in order with most common first) in 6 to 60 years

A

Strep pneumo, N meningitidis (number 1 in teens), Enteroviruses, HSV

330
Q

Most common causes of meningitis (in order with most common first) in elderly

A

Strep pneumo, GNRs, Listeria

331
Q

Enteroviruses

A

Coxsackie, Echo, Polio, others

332
Q

CSF findings in viral meningitis

A

WBC below 500 predominantely lymphocytes, glucose normal or near normal, protein elevated but below 70

333
Q

Treatment of meningitis

A

Cetriaxone and vanco empirically. Add ampicillin if Listeria suspected

334
Q

Fever, headache, photophobia, nuchal rigidity, painful extraocular movements

A

Meningitis

335
Q

CSF findings in fungal/Tb meningitis

A

Very similar to bacterial except WBC predominance is lymphocytes instead of PMNs

336
Q

Fever with positive gallium scan

A

Osteomyelitis

337
Q

Most common causes of osteomyelitis in: all comers, sexually active, DM and IVDU, sickle cell, prosthetics, vertebral, animal bite

A

All - S aureus, Sexually active - N gonorrhoeae (rare), DM and IVDU - pseudomonas, Sickle - Salmonella, Prosthetics - S aureus and s epidermis, Vertebral - M Tb (potts disease), Animal bite - Pasteurella

338
Q

Where in the bone does osteomyelitis typically occur

A

Metaphysis of long bones

339
Q

Features seen in pyelonephritis but not cystitis

A

Fever, chills, flank (vs suprapubic) pain, CVA tenderness, hematuria, WBC casts (vs WBCs)

340
Q

Predisposing factors to UTI

A

Female, obstruction, kidney surgery, catheterization, GU malformation, DM, pregnancy

341
Q

Markers for UTI agents

A

Positive leukocyte esterase test - bacterial UTI, Positive nitrite test - gram negative bacterial UTI

342
Q

Urease producing bugs that cause UTIs

A

Proteus, Klebsiella. Negative urease test suggests E coli, Strep, Enterococcus

343
Q

ToRCHHeS

A

Toxoplasma, Rubella, CMV, HIV, HSV-2, Syphilis

344
Q

Hepatosplenomegaly, jaundice, thrombocytopenia, growth retardation in newborn

A

Common features of ToRCHHeS infections

345
Q

Which TORCHES infection often includes poor feeding?

A

Toxoplasma

346
Q

Maternal symptoms for each of the ToRCHHeS infections

A

Toxo - asymptomatic or lymphadenopathy. Rubella - Rash, postauricular lymphadenopathy, polyarthritis. CMV - Asymptomatic or mono-like. HIV - variable. HSV-2 - Asymptomatic or herpetic lesions. Syphilis - Chancre, rash, or cardiac/neuro disease

347
Q

PDA, cataracts, deafness, blueberry muffin rash (may or may not be present)

A

Congenital rubella

348
Q

Hearing loss, seizures, petechial rash, blueberry muffin rash

A

Congenital CMV

349
Q

Recurrent infections, chronic diarrhea in newborn

A

Congenital HIV

350
Q

Temporal encephalitis, herpetic lesions in newborn

A

Congenital HSV-2

351
Q

Stillbirth or facial abnormalities, saber shins, and CN 8 deafness

A

Congenital syphillis

352
Q

Slapped cheek rash

A

Parvo B19

353
Q

Vesicular rash on palms and soles. Ulcers in oral mucosa

A

Coxsackie Type A (hand-foot-mouth disease)

354
Q

Urethritis, cervicitis, PID, prostatitis, epididymitis, arthritis, creamy purulent discharge

A

Gonorrhea

355
Q

Painful genital ulcer, inguinal adenopathy

A

Chancroid (haemophilus ducreyi)

356
Q

Painful penile, vulvar, or cervical vesicles and ulcers. With or without fever, headache, myalgia

A

HSV-2

357
Q

Noninflammatory, malodorous discharge, positive whiff test, clue cells

A

Gardnerella vaginosis

358
Q

Two most common causes of PID

A

Chlamydia trachomatis and N gonorrhoeae

359
Q

Cervical motion tenderness, purulent cervical discharge

A

PID. May progress to salpingitis, endometritis, hydrosalpinx, and tubo-ovarian abscess

360
Q

Fitz-Hugh-Curtis

A

Infection of the liver capsule and violin string adhesions of parietal peritoneum to liver. Caused by ascending PID (esp N gonorrhoeae)

361
Q

Causes of meningitis in unimmunized children

A

HiB and polio

362
Q

What bug should you associate with sulfur granules?

A

Actinomyces israelii

363
Q

Action of penicillin and its dervitives

A

Block cell wall synthesis by inhibition of peptidoglycan cross linking

364
Q

Drugs that block peptidoglycan synthesis

A

Bacitracin, vancomycin

365
Q

Drugs that block nucleotide synthesis

A

Sulfonamides, trimethoprim

366
Q

Drugs that block DNA topoisomerases

A

Fluoroquinolones

367
Q

Drugs that block mRNA synthesis

A

Rifampin

368
Q

How does metronidazole work?

A

Damages DNA

369
Q

Dicloxacillin

A

A penicillin derivative related to methicillin and nafcillin

370
Q

Which has greater oral bioavailability, amoxicillin or ampicillin?

A

Amoxicillin

371
Q

Main uses of ampicillin and amoxicillin

A

H flu, E coli, Listeria, Proteus, Salmonella, Shigella, enterococci

372
Q

Most important use of ticarcillin, carbenicillin, and piperacillin

A

Pseudomonas. Also covers GNRs

373
Q

Clavulanic Acid, Sulbactam, Tazobactam

A

B-lactamase inhibitors

374
Q

What do cephalosporins block?

A

Transpeptidases (also called penicillin binding proteins)

375
Q

Organisms not covered by cephalosporins are LAME

A

Listeria, Atypicals (chlamydia, mycoplasma), MRSA, Enterococci

376
Q

Toxicities of cephalosporins

A

Hypersensitivity reactions, Vitamin K deficiency, Disulfiram-like reaction

377
Q

Aztreonam

A

Monobactam resistant to B-lactamases. Binds PBP3, no cross-allergenicity with penicillins. GNR coverage only.

378
Q

Main use of aztreonam

A

Penicillin-allergic pts and those with renal insufficiency who cannot tolerate aminoglycosides

379
Q

Imipenem/cilastatin and meropenem

A

Limited by side effects, use in life-threatening infections after other options exhausted.

380
Q

Cilastatin

A

Inhibits renal dehydropeptidase to decrease inactivation of imipenem

381
Q

What are penicillins structural analogs of in bacteria?

A

The D-Ala-D-Ala sequence (which vancomycin binds)

382
Q

Toxicities of vancomycin

A

Nephrotoxicity, Ototoxicity, Thrombophlebitis, red man syndrome

383
Q

What causes vancomycin resistance?

A

Change of D-ala-D-ala to D-ala-D-lac

384
Q

Protein synthesis inhibitor targets

A

buy AT 30, CCEL at 50. 30S - Aminoglycosides, Tetracyclines. 50S - Chloramphenicol, Clindamycin, Erythromycin (macrolides), Linezolid

385
Q

Aminoglycosides (5)

A

Gentamicin, Neomycin, Amikacin, Tobramycin, Streptomycin

386
Q

Action of aminoglycosides

A

Inhibit formation of initiation complex and cause misreading of mRNA (bactericidal)

387
Q

What type of bacteria are aminoglycosides ineffective against and why?

A

Anaerobes, because they require O2 for uptake

388
Q

Main use of aminoglycosides

A

Severe GNR infections

389
Q

Toxicities of aminoglycosides

A

Nephrotoxicity, Ototoxicity, Teratogenic

390
Q

Resistance of aminoglycosides

A

Transferase enzymes inactivate drug by acetylation, phosphorylation, or adenylation

391
Q

Tetracyclines (4)

A

Tetracycline, doxycycline, demeclocycline, minocycline

392
Q

Which tetracycline is used in a renal disorder and which disorder?

A

Demeclocycline (ADH antagonist) is used in SIADH

393
Q

Action of tetracyclines

A

Bind 30S, prevent aminoacyl-tRNA attachment

394
Q

Instructions for patients taking tetracyclines

A

Do not take with milk, antacids, or iron-containing preparations as these will inhibit tetracycline absorption

395
Q

What makes tetracyclines so effective against Rickettsia and Chlamydia

A

They accumulate intracellularly

396
Q

Action of macrolides

A

Bind 50S (23S rRNA subsubunit) and prevent translocation

397
Q

Main uses of macrolides

A

Atypical pneumonias, URIs, STDs, gram positive cocci, Neisseria

398
Q

Toxicities of macrolides

A

Prolonged QT, GI discomfort (most common cause of noncompliance), acute cholestatic hepatitis, eosinophilia, skin rashes

399
Q

What drugs are increased in plasma concentration by macrolides?

A

Theophyllines and oral anticoagulants

400
Q

Action of chloramphenicol

A

Binds 50S - blocks peptide bond formation

401
Q

Resistance to chloramphenicol

A

Plasmid-encoded acetyltransferase inactivates drug

402
Q

Action of clindamycin

A

Binds 50S - blocks peptide bond formation

403
Q

Main uses of clindamycin

A

Anaerobic infections in aspiration pneumonia or lung abscesses

404
Q

General principle for treating anaerobes

A

Above the diaphragm - clindamycin, Below the diaphragm - metronidazole

405
Q

Sulfonamides (3)

A

Sulfamethoxazole (SMX), sulfisoxazole, sulfadiazine

406
Q

Action of sulfonamides

A

Inhibit dihydropteroate synthase (needed for DNA synthesis). Are PABA antimetabolites

407
Q

Fluoroquinolones (9)

A

Ciprofloxacin, norfloxacin, levofloxacin, ofloxacin, sparfloxacin, moxifloxacin, gatifloxacin, enoxacin, nalidixic acid (a quinolone)

408
Q

Uses for metronidazole

A

Giardia, Entamoeba, Trichomonas, Gardnerella, Anaerobes.

409
Q

Toxicities of metronidazole

A

Disulfiram-like reaction, headache, metallic taste

410
Q

Prophylaxis for Tb, MAI, and M leprae respectively

A

Tb - INH, MAI - Azithromycin, M leprae - None

411
Q

What is responsible for acid fastness?

A

Mycolic acids

412
Q

What is needed to activate INH?

A

Bacterial catalase-peroxidase (KatG)

413
Q

Toxicities of INH

A

Neurotoxic, hepatotoxic, lupus. Pyridoxine (B6) can prevent neurotoxicity and lupus

414
Q

What causes different INH half life in different individuals

A

Fast vs slow acetylators

415
Q

4 Rs of Rifampin

A

RNA polymerase inhibitor, Revs up P-450, Red/orange body fluids, Rapid resistance if used alone

416
Q

Pyrazinamide

A

Anti-tb. Inhibits mycolic acid production by blocking pyrazanamidase

417
Q

Ethambutol

A

Anti-tb. Decreases carbohydrate polymerization of cell wall by blocking arabinosyltransferase. Can cause optic neuropathy (red-green color blindness)

418
Q

Prophylaxis for each of the following: meningococcus, gonorrhea, syphilis, recurrent UTIs, endocarditis with surgical or dental procedures

A

Meningococcus - Cipro, rifampin or minocycline. Gonorrhea - Cetriaxone, Syphilis - Benzathine penicillin G, Recurrent UTI - Bactrim, Endocarditis - Penicillins

419
Q

HIV prophylaxis at CD4 below: 200, 100, and 50

A

200 - Bactrim (PCP), 100 - Bactrim (PCP and Toxo), 50 - Above and Azithryomycin (MAI)

420
Q

Treatment for VRE

A

Linezolid and quinupristin/dalfopristin

421
Q

Empiric therapy for community-acquired pneumonias

A

Outpatient - macrolides, Inpatient - fluoroquinolones, ICU - B-lactam + (fluoroquinolone or azithromycin)

422
Q

What antifungals affect each of the following: membrane function, cell wall synthesis, ergosterol synthesis, lanosterol synthesis, nucleic acid synthesis

A

Membrane - Amphotericin B, Cell wall - Caspofungin, Ergosterol - fluconazole, itraconazole, voriconazole, terbinafine, Lanosterol - naftitine, Nucleic Acids - 5-fluorocytosine

423
Q

Action of amphotericin B

A

Binds ergosterol and forms pore that allow leakage of electrolytes

424
Q

What do you have to supplement in amphotericin treatment and why?

A

K and Mg because of altered renal tubule permeability

425
Q

Action and delivery of nystatin

A

Same as amphotericin (binds ergosterol and makes pores). Topical only because too topic systemically

426
Q

Action of caspofungin

A

Inhibits cell wall synthesis by inhibiting synthesis of B-glucan

427
Q

Action of terbinafine

A

Inhibits fungal enzyme squalene epoxidase (necessary for ergosterol synthesis)

428
Q

Action of griseofulvin

A

Inhibits MT function, disrupting mitosis

429
Q

Antiprotozoals (5)

A

Pyrimethamine (toxo and falciparum), suramin and melarsoprol (sleeping sickness), nifurtimox (Chagas), Sodium stibogluconate (leishmaniasis)

430
Q

Action of chloroquine

A

Blocks plasmodium heme polymerase

431
Q

Antihelminthic drugs

A

Mebendazole, pyrantel pamoate, ivermectin, DEC, praziquantel. They all immobilize helminths

432
Q

Amantadine

A

Blocks viral penetration and uncoating (M2 protein). Causes release of dopamine from nerve terminals

433
Q

Use and toxicity for amantadine

A

Influenza A, Parkinsons disease. Causes ataxia, dizziness, slurred speech. 90 pct of influenza A resistant to amantadine

434
Q

Zanamivir and oseltamivir

A

Inhibit neuraminidase, decreasing release of progeny viruses. Use in both Influenza A and B

435
Q

Ribavirin

A

Inhibits synthesis of guanine nucleotides by competitively inhibiting IMP dehydrogenase. Use in RSV and Hep C. Can cause hemolytic anemia, is teratogenic

436
Q

Activation and Action of Acyclovir

A

Monophosphorylated by HSV/VZV thymidine kinase. Guanosine analog

437
Q

Uses of acyclovir

A

HSV, VZV, EBV. Use famciclovir for herpes zoster

438
Q

Toxicities of acyclovir

A

Can cause crystalline nephropathy if adequate hydration not provided

439
Q

Uses of ganciclovir

A

CMV

440
Q

Toxicities of gancicyclovir

A

Leukopenia, neutropenia, thrombocytopenia, renal toxicity. Much more toxic than acyclovir

441
Q

Foscarnet

A

Viral DNA pol inhibitor (binds pyrophosphate-binding site, no activatoin required).

442
Q

What effect does foscarnet have on electrolyte levels

A

Can chelate Ca and promote Mg wasting (leads to low Ca and Mg levels)

443
Q

Cidofovir

A

Inhibits viral DNA pol. Does not require phosphorylation. Nephrotoxic (give with probenecid)

444
Q

HAART regimens

A

2 NRTIs with 1 NNRTIs or 1 PI or 1 Integrase inhibitor

445
Q

Lopinavir, atazanavir, darunavir, fosamprenavir, saquinavir, ritonavir, indinavir

A

Protease inhibitors

446
Q

Toxicities of protease inhibitors

A

Hyperglycemia, GI intolerance, lipodystrophy (fat redistribution similar to Cushings)

447
Q

NRTIs (7)

A

Tenofovir, Emtricitabine, Abacavir, Lamivudine, Zidovudine, Didanosine, Stavudine

448
Q

Toxicities of NRTIs

A

Bone marrow suppression, peripheral neuropathy, lactic acidosis, rash, megaloblastic anemia

449
Q

NNRTIs (3)

A

Nevirapine, Efavirenz, Delaviridine

450
Q

Raltegravir

A

Integrase inhibitor. Inhibits HIV genome integration. Can cause hypercholesterolemia

451
Q

Uses for each of the interferons

A

Alpha - Chronic Hep B and C, Kaposi sarcoma. Beta - MS. Gamma - NADPH oxidase deficiency

452
Q

Toxicities of the interferons

A

Neutropenia

453
Q

Antimicrobials to avoid in pregnancy

A

Countless SAFe Moms Take Really Good Care. Clarithromycin, Sulfonamides, Aminoglycosides, Fluoroquinolones, Metronidazole, Tetracyclines, Ribavirin, Griseofulvin, Chloramphenicol

454
Q

What bacterium likes the gallbladder?

A

Salmonella typhi