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Flashcards in URT infections Deck (76)
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1
Q

the common cold

A

rhinovirus vs. coronavirus

2
Q

the most common agent of the common cold is..

A

rhinovirus THEN coronavirus

3
Q

ddx allergic rhinitis

A

blue-colored nasal passages
clear, serous fluid-colored rhinorrhea
“nasal salute”
itchy, serous discharge conjunctivitis

4
Q

ddx purulent rhinitis

A

lasts longer: 14 d (vs. 4-5)
thicker, denser rhinorrhea
caused by Hib
DO NOT USE ABX

5
Q

coronavirus is enveloped, therefore

A

does not survive as long in the environment (no fomite transfer)

6
Q

period of incubation is shorter in..

A

Rhinovirus (poss. hrs) vs coronavirus (3 days)

7
Q

most important Ab for Rhinovirus* viral immunity is

A

IgA2 (but only short term immunity)

8
Q

rhinovirus uses this as cell surface receptor

A

ICAM-1

9
Q

is fever seen in rhinovirus or coronavirus?

A

rarely

10
Q

other viral agents that cause infectious rhinitis

A
influenza v type C 
adenovirus
RSV
influenza v type A or B
PIV
hMPV
other enteroviruses
11
Q

bacterial infections that can cause rhinitis

A

Bordetella pertussis
Mycoplasma pneumoniae
Chlamydia pneumoniae

12
Q

DO NOT want to use ASA in children bc

A

could cause Reye’s syndrome if influenza virus, VZV?

13
Q

Moraxella catarrhalis

A

G-diplococci, kidney bean, non-encap, non-staining, Ox +
3rd most common cause of AOM
3rd: BAC cause of acute sinusitis
3rd: BAC cause of AE-CB or COPD/emphysema
imp. LRTI (tracheitis–>pneumonia)

14
Q

viral agents of sinusitis

A

Rhinovirus
Influenza V
PIV

15
Q

bac agents of sinusitis

A

Strep pneumonia
NTHi
Moraxella catarrhalis (N. or B.)

16
Q

unique risk factor for sinusitis

A

Prim. ciliary dyskinesia (PCD) aka immotile ciliary syndrome or Kartagener syndrome (KS)

17
Q

main pathogenic event

A

closure of sinus ostia

18
Q

most common sinus of sinusitis

A

Maxillary, then ethmoid, frontal, sphenoid (MEFS)

19
Q

fever with sinusitis?

A

may have low grade fever

20
Q

purulent nasal discharge in sinusitis implies

A

bac. etiology, GIVE ABX

other bac. signs: sig. pain, prolonged duration (>7-10 d)

21
Q

acute sinusitis can become a medical emergency if spread to

A

eye
bone
CNS

22
Q

xray for sinusitis?

A

subj. decision, cannot distinguish btw viral, allergic, bac.

* is a MUST if complications suspected

23
Q

dx tenderness over CN V…

A

CN V2 for maxillary sinusitis, CN V1 for others

24
Q

acute sinusitis is tx w/

A

abx: amoxicillin, amoxicillin-clavulanic acid (Augmentin)
*BUT should be w.held for 10-14 d unless sev. symps : use analgesics, decongestants and “watchfully wait”
DO NOT use antihistamines unless allergic rhinitis
Hypertonic saline nasal irrigation (HSNI)

25
Q

most common causes of OE

A

Pseudomonas*, staphylococci (coag +/-) fungi

26
Q

OE: pus? TM involved? fever?

A

possibly to all,
if TM, no fluid should be behind, if there is
–>OE + AOM

27
Q

OE: syst. abx?

A

NO, local topical abx +/- cortisone

28
Q

AOM agents: ALL BACTERIA

A

*Streptococcus pneumoniae (G+ lancet diplococci)
*NTHi (G- coccobacilli)
*Moraxella catarrhalis (G- diplococci)
GABHS (S. pyogenes) and S. aureus (coag+)
Mycoplasma pneumoniae and Chlamydia pneumoniae
*no viral cause, but virus may be present

29
Q

AOM: pus?

A

YES; bac inf; it is pyogenic

30
Q

OME: pus?

A

NO; serous fluid, biofilm (chron. bac inf)

31
Q

AOM ddx

A
fever 
bulging, opaque, immobile TM
otorrhea (discharge) if perf. TM
worse complications:
can lead to OME
hearing impairment, TM rupture, Mastoiditis
32
Q

OME ddx

A

NO FEVER
TM MAY BE NORMAL
serous fluid in middle ear (air bubbles, fluid)
otorrhea (serous fluid) if perf. TM

33
Q

AOM: abx?

A

complicated: 80% resolve spont., otherwise amoxicillin, augmentin if failure
- need other meds for pain relief

34
Q

OME: abx?

A

not unless chronic (>4 mos)

will not help serous effusion

35
Q

AOM: prevention?

A

yes:
1. Prevenar 7-valent and 13-valent conjugated vaccine
- prev. inv. pneumococcal disease, pneumo, mening, bacteremia
2. Influenza trivalent inact. vaccine (TIV), LAIV (live atttnd intranasal vaccine)
3. S. pneumo 23 valent polysacc. vaccine: Pneumovax/Pneu-imune

36
Q

acute myringitis ddx

A

same bac agents as AOM +/- viral agents
TM inflammation may occur ALONE or w/ OE or OME
bullous: blisters or hemorrhagic

37
Q

rhinovirus and coronavirus can cause “pharyngitis” but do not

A

replicate in pharyngeal tissue

38
Q

these viruses can replicate in pharyngitis

A

Adenovirus and Strep pyogenes

39
Q

the primary agent of pharyngitis (URI) and 3rd most common cause of LRI in children

A

Adenovirus
(non-env.) A–>F (Ad7 *)
most commonly affect kids

40
Q

main causes of LRIs

A
  1. RSV 2.PIV 3. Adenovirus* 4.hMPV

* most severe and highest mortality rate (esp. pneumonia)

41
Q

adenovirus: causes fever?

A

yes, also cause of pharyngoconjunctival fever (PCF): summer, swimming pools

42
Q

adenovirus s/s indistinguishable from

A

Strep pyogenes infection (GAS)

both: fever, tonsillar exudates, ANT. cerv. lymphadena

43
Q

pharyngitis is more likely to be viral if

A

temp is lower, coryza and cough are present, no N/V/abd pn

tx: DO NOTHING; self-limiting (3-7 days)

44
Q

adenovirus can cause LRT disease that looks like

A

Pertussis

45
Q

if adenovirus, will observe these on microscopic observation

A

mononuclear infiltrates (lymphocytes and monocytic cells)

46
Q

Streptococcus pyogenes

A
G+ cocci in chains
aerotolerant anaerobe
Catalase neg
B-hemolytic
(GAS or GABHS)
47
Q

S. pneumoniae

A

a-hemolytic; causes pneumo, mening, OM, sinusitis, septicemia, conjunc.

48
Q

S. agalactiae

A

B-hemolytic: causes neonatal septicemia w. pneumo and mening

49
Q

S. mutans, S. mitis

A

a-hemolytic Strep; NF of mouth and l. int, causes dental caries, infective endocarditis

50
Q

GABHS causes suppurative (pus-producing) disease

A

pharyngitis, OM, sinusitis, mastoiditis, pneumo

-impetigo, ecthyma, erysipelas, cellulitis, necrotizing fasciitis

51
Q

GABHS causes non-suppurative, immunpath-med disease

A

RF, PSRA, PANDAS, AGN

52
Q

GABHS causes exotoxin-mediated disease (superAgs)

A

scarlet fever, STSS

53
Q

the most common cause of BACTERIAL pharyngitis

A

S. pyogenes (GABHS) **still less common than viral pharyngitis (Ad)

54
Q

pharyngitis from GAS: self-limiting? tx??

A

it IS self-limiting, BUT YOU NEED TO TX: want to prevent spread, reduce duration (NOT throat pain), and **prevent agains RH or AGN by suppressing host’s self-limiting imm resp. against GAS (can lead to RH or AGN)
tx: PNC V or cephalosporins
for hypersn. pts: eryth, linco, clindamycin
*also want to treat bac/fungal inf. bc they may not be self-limiting

55
Q

non-suppurative sequelae of GAS

A

RF: heart (carditis), skin (nodules), joints (arthritis), CNS (chorea), FEVER
AGN: follow phary. or integumental inf., TIII hypersn., self-limiting

56
Q

RF tx

A

bed rest, benzathine penicillin G or procaine penicillin

sympto: salicylates (ASA)

57
Q

PANDAS

A

ADHD, Tourett’s, OCD, tic disorder

58
Q

Scarlet fever caused by

A

GAS w/ SPEs (strep pyrogenic exotoxins)
complication of pharyng. and integumental inf.
exanthem: scarlatiniform “sand-paper” rash
enanthem: petechia on palate, bleeding, red strawberry tongue
tx to prevent RF/AGN

59
Q

Lemierre syndrome

A
thrombophlebitis of IJV-->septic emboli-->lung, brain, joints
Fusobacterium necrophorum (G- bacillus, ob. anaerobe)
60
Q

Corynebacterium diphtheriae

A

G+ rods, may be club shaped (diphtheroids)
aerobic
*non-invasive

61
Q

this is req. for diphtheria (“throat distemper”)

A

exotoxin production: reg by [Fe]: opposite reg
inhibits protein synthesis–>cell death via necrosis–>inflammatory reaction–>fibrinous exudate–>pseudomembrane forms, edema (“bull neck”)–>non-invasive but toxemia (the toxin, not bacteremia) can occur

62
Q

fever in diphtheria?

A

yes, low grade

63
Q

diphtheria: pseudomembrane

A

gray-black, not pathognomonic (cerv. adenines, GAS)

64
Q

how to dx diphtheria

A

clinical findings, Gs (“chinese char.” G+rods), Cx, Elek test to demonstrate toxigenic

65
Q

diphteria tx

A

maintain airways, antitoxin abs, abx (PCN G, eryth) as adjunct

66
Q

Haemophilus influenza

A

most common cause of acute epiglottitis-AE (Hib)

2nd to S. pneumo for OM, sinusitis (NTHi)

67
Q

H. flu type aegyptius assoc. w/

A

conjunct, Brazilian purpuric fever

68
Q

H. influenza character

A

v. small G-coccobacilli, ox + (pleomorph in CSF)
anti-phago capsule, type b is most important: strain (PRP) : Hib
grows on chocolate agar

69
Q

Hib is a frank pathogen, in contrast to..

A

NTHi: NF of nasopharynx

70
Q

non-invasive NTHi diseases

A

OM, sinusitis, conjunc/conjunc-OM synd, bronchitis and pneumo

71
Q

invasive Hib diseases

A

mening, bacterimia, facial cellulitis, septic arthritis, secondary bacterial pneumo

72
Q

AE: fever?

A

YES
+“air hunger” +insp. stridor + “barking/hot potato voice” + “bull neck”+ “thumb sign” + SUPRAglottic edema + beefy red epiglottis w. purulence

73
Q

AE org dx

A

FIRST MAINTAIN AIRWAY med emergency

-Hib, then pneumococcus, then GAS

74
Q

AE tx

A

after airway maintained

cefuoxime, cefotaxime, ceftriaxone, TMP-SMX

75
Q

Hib vaccine…

so now use..

A

are type II-T-independent so: IgM only, no memory (short term imm.), not protective in kidsswitch to sIgA2, induce memory (B cells), rec. @ 2mos
*don’t bundle w/dTap

76
Q

other causes of sinusitis: fungal

A

aka Rhinocerebral mucormycosis

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