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Flashcards in URT infections Deck (76):
1

the common cold

rhinovirus vs. coronavirus

2

the most common agent of the common cold is..

rhinovirus THEN coronavirus

3

ddx allergic rhinitis

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

4

ddx purulent rhinitis

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

5

coronavirus is enveloped, therefore

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

6

period of incubation is shorter in..

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

7

most important Ab for Rhinovirus* viral immunity is

IgA2 (but only short term immunity)

8

rhinovirus uses this as cell surface receptor

ICAM-1

9

is fever seen in rhinovirus or coronavirus?

rarely

10

other viral agents that cause infectious rhinitis

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

11

bacterial infections that can cause rhinitis

Bordetella pertussis
Mycoplasma pneumoniae
Chlamydia pneumoniae

12

DO NOT want to use ASA in children bc

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

13

Moraxella catarrhalis

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

viral agents of sinusitis

Rhinovirus
Influenza V
PIV

15

bac agents of sinusitis

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

16

unique risk factor for sinusitis

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

17

main pathogenic event

closure of sinus ostia

18

most common sinus of sinusitis

Maxillary, then ethmoid, frontal, sphenoid (MEFS)

19

fever with sinusitis?

may have low grade fever

20

purulent nasal discharge in sinusitis implies

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

21

acute sinusitis can become a medical emergency if spread to

eye
bone
CNS

22

xray for sinusitis?

subj. decision, cannot distinguish btw viral, allergic, bac.
*is a MUST if complications suspected

23

dx tenderness over CN V...

CN V2 for maxillary sinusitis, CN V1 for others

24

acute sinusitis is tx w/

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

most common causes of OE

Pseudomonas*, staphylococci (coag +/-) fungi

26

OE: pus? TM involved? fever?

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

27

OE: syst. abx?

NO, local topical abx +/- cortisone

28

AOM agents: ALL BACTERIA

*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

AOM: pus?

YES; bac inf; it is pyogenic

30

OME: pus?

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

31

AOM ddx

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

32

OME ddx

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

33

AOM: abx?

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

34

OME: abx?

not unless chronic (>4 mos)
will not help serous effusion

35

AOM: prevention?

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

acute myringitis ddx

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

37

rhinovirus and coronavirus can cause "pharyngitis" but do not

replicate in pharyngeal tissue

38

these viruses can replicate in pharyngitis

Adenovirus and Strep pyogenes

39

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

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

40

main causes of LRIs

1.RSV 2.PIV 3. Adenovirus* 4.hMPV
*most severe and highest mortality rate (esp. pneumonia)

41

adenovirus: causes fever?

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

42

adenovirus s/s indistinguishable from

Strep pyogenes infection (GAS)
both: fever, tonsillar exudates, ANT. cerv. lymphadena

43

pharyngitis is more likely to be viral if

temp is lower, coryza and cough are present, no N/V/abd pn
tx: DO NOTHING; self-limiting (3-7 days)

44

adenovirus can cause LRT disease that looks like

Pertussis

45

if adenovirus, will observe these on microscopic observation

mononuclear infiltrates (lymphocytes and monocytic cells)

46

Streptococcus pyogenes

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

47

S. pneumoniae

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

48

S. agalactiae

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

49

S. mutans, S. mitis

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

50

GABHS causes suppurative (pus-producing) disease

pharyngitis, OM, sinusitis, mastoiditis, pneumo
-impetigo, ecthyma, erysipelas, cellulitis, necrotizing fasciitis

51

GABHS causes non-suppurative, immunpath-med disease

RF, PSRA, PANDAS, AGN

52

GABHS causes exotoxin-mediated disease (superAgs)

scarlet fever, STSS

53

the most common cause of BACTERIAL pharyngitis

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

54

pharyngitis from GAS: self-limiting? tx??

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

non-suppurative sequelae of GAS

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

56

RF tx

bed rest, benzathine penicillin G or procaine penicillin
sympto: salicylates (ASA)

57

PANDAS

ADHD, Tourett's, OCD, tic disorder

58

Scarlet fever caused by

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

Lemierre syndrome

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

60

Corynebacterium diphtheriae

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

61

this is req. for diphtheria ("throat distemper")

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

fever in diphtheria?

yes, low grade

63

diphtheria: pseudomembrane

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

64

how to dx diphtheria

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

65

diphteria tx

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

66

Haemophilus influenza

most common cause of *acute epiglottitis*-AE (Hib)
2nd to S. pneumo for OM, sinusitis (NTHi)

67

H. flu type aegyptius assoc. w/

conjunct, Brazilian purpuric fever

68

H. influenza character

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

69

Hib is a frank pathogen, in contrast to..

NTHi: NF of nasopharynx

70

non-invasive NTHi diseases

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

71

invasive Hib diseases

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

72

AE: fever?

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

73

AE org dx

FIRST MAINTAIN AIRWAY *med emergency*
-Hib, then pneumococcus, then GAS

74

AE tx

after airway maintained
cefuoxime, cefotaxime, ceftriaxone, TMP-SMX

75

Hib vaccine...
so now use..

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

other causes of sinusitis: fungal

aka Rhinocerebral mucormycosis

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