Ch5: URT Chaussee Flashcards
What does upper respiratory mean?
Above larynx
How does number of microbes change throughout lung?
Very high in the mouth
Decreases as you move down the respiratory tract
None in lungs
Where does RT become aseptic?
Alveolar bronchiole
Normal flora has what role in RT?
Protects by competing with harmful microbes
What bacteria are in middle ear and sinuses?
None, sterile
Normal flora of URT? (50% of people or more)
- Corynebacteria
- Candida albicans
- Alpha-hemolytic strep
- Strep mutants
- Haemophilus influenzae
- Neisseria
- Non staph aureus staph
Host defenses in URT?
- Orthogonal structure
- Saliva
- Mucin and mucus
- TLR’s
the orthagonal structure of URT has what effect?
Traps microbes
What does saliva contain? 2
Lysozyme
Secretory IgA
What does mucus do?
Traps microbes from entering LRT.
What sweeps mucus up and out and into stomach?
Ciliated epithelial cells
Ciliated epithelial cells + Mucus = ?
Mucocilliary escalator
50-70% of sore throats are caused by what in children?
Viruses
What symptoms suggest a viral sore throat?
Conjunctivitis Coryza Ulcerative lesions Viral exanthema Diarrhea
What percentage of adult sore throats are viral?
0%
Bacterial causes of pharyngitis?
- Group A strep:
- Group C and G strep
- Anaerobes (bacterioides, fusobacterium, spirochetes
- Corynebacterium diptherae
- Neisseria gonorrhoea
Which bacterial causes of pharyngitis are common?
Infrequent?
Group A strep = common
Group C and G strep = infrequent
Neisseria gonorrhea = infrequent
GAS caused pharyngitis has what associations? 3
Tonsilitis, scarlet fever, sequelae
What are spirochetes that cause pharyngitis?
What else are they associated with?
Borrelia and treponema
Trench mouth
In terms of GAS strep throat
Onset?
Symptoms? (3)
- Severe pain
- Difficulting swallowing
- Flu-like
Suppurative sequelae of GAS? 4
- Peritonsillar abscess
- Otitis media, sinusitis, mastoiditis
- Scarlet fever
- Streptococcal Toxic Shock Syndrome
Scarlet fever encompasses what?
Peripheral rash (Maybe strawberry tongue) caused by SPE’s
What is STSS due to?
Production of Spe’s that act as superantigens
What happens if GAS is in the blood?
Bacteremia and toxigenic disease
Non-suppurative/post infection sequelae to GAS pharyngitis?
Acute rheumatic fever: Due to autoimmune
Why does acute rheumatic fever occur?
How long does it take to develop?
What percent of kids get it?
M protein mimics cardiac myosin
3 weeks
3%
Clinical diagnosis of ARF is based on what?
Jones criteria
ARF typically follows what type of GAS infection?
Pharyngeal
What is the Jones criteria requirements for GAS?
Evidence of previous GAS infection
2 major or 1 major + 2 minor
Major manifestations of ARF? 5
- Joints
- Heart inflammed
- Nodules subcutaneous
- Erythema marginatum
- Sydenham’s Chorea
Minor manifestations of ARF? 4
- Previous ARF
- Fever
- Joints
- Acute phase reaction
Laboratory obtained evidnece of previous GAS infection?
Anti-streptolysin O test
Besides ARF, what else is a non-suppurative post infection sequlae of GAS?
Pediatric Autoimmune Neuropsychiatric Disorders Associated WIth Strep Infections (PANDAS)
What causes PANDAS?
Cross reactivity between GAS antigens and neuro tissue
GAS may be responsible for what neuro disorders?
- OCD
2. Tourettes
Lab diagnosis of GAS? (7)
- Rapid diagnostic test (Ab’s to GAS carb)
- Culture throat swab
- Beta-hemolytic
- Gram positive
- Catalase negative
- Bacitracin sensitive
- Positive PYR test
Treatment of all GAS children should be what?
What about adults?
Antibiotics
Not so much since usually due to virus
Main drugs for GAS sore throat? (2)
- Penicillin
2. Erythromycin for kids with allergies
Group C and G strep is what type of hemolytic?
Gram positive?
Beta-hemolytic
Gram positive
Habitat of Group C and G strep?
- Mucosal surfaces like nasopharynx
Transmission of Group C and G?
Droplets or direct contact
Do GCS and GGS have M protein?
Yes
What is the one suppurative of GCS/GGS infection?
What are the two non-suppuratives
Pharyngitis
GLomerulonephritis: Group C
ARF: Group C and G
Laboratory diagnosis of GCS and GGS?
- Rapid diagnostic
- Beta hemolytic
- Gram + cocci in chains
- Catalase negative
- Bacitracin resistant
- PYR Negative
Treatment of GCS and GGS? 2
Penicillin or macrolides
Neisseria gonorrhoeae is what in gram stain?
Gram-negative
Habitat of neisseria gonorrhoeae?
Humans
Transmission of N. gonorrhoeae?
Sexual contact
Lab diagnosis of N. gonorrhoeae is on what medium? 2
Chocolate agar or Thayer-Martin agar
What is Thayer-martin agar?
Chocolate agar + antibiotics for most bacteria and fungi
Treatment of N. gonorrhoeae? 2
- Intramuscular Ceftriaxone
2. Oral azithromycin or doxycycline
What is N. gonorrhoeae resistant to?
Penicillin and Tetra
Acute otitis media is what?
Inflammation of mucosa in tympanic cavity
What starts AOM?
Obstruction or blockage of the Eustachian tube or opening to sinuses
Result of obstruction in Eustachian tube or sinuses?
Microbial products accumulate –> Inflammation
AOM diseases are treated with what?
Amoxicillin or cephalosporins
Infants and children are susceptible to otitis media why?
Eustachian tube is shorter and more linear.
Why are infants more susceptible to otitis media?
Eustachian tube is shorter and more linear
What percentage of otitis media is caused by viruses?
50%
Common bacterial causes of otitis media?4
Haemophilus INfluenzae
Strep Pneuoniae
Moraxella catarrhalis
Strep pyogenes/Staph aureus
What is unique of the bacterial causes of otitis media?
They are all normal flora of URT
Hemophilus influenzae is gram what? Shape? (2) Respiration? Divided into serotypes based on what? Which is most virulent?
Gram - Rods or coccobacilli Facultative anaerobe 6 capsular anaerobes Type B
Habitat of H. influenzae?
Humans in throat and skin
What type of H. influenzae do people get at birth?
Non-encapsulated H. influenzae
Transmission of H. influenzae?
Respiratory droplets or direct contact
VIrulence factors of H. influenzae?
Polysaccharide capsule
Type B H. influenzae capsule has what important component?
Polyribitol phosphate (PRP) that Ab’s attack
Infections caused by H. influenzae? 4
AOM, meningitis, pneumoniae, acute epiglottis
Vaccine against H. influenzae?
Yes, protein conjugate virus of PRP linked to a protein like tetanus toxoid or meningococcal outer membrane protein
Strep pneumoniae is in what form?
Gram stain?
Hemolytic?
Shape?
Encapsulated
Gram +
Alpha hemolytic
Lancet shape in diplococci
Habitat of Strep pneumoniae?
Human URT
Transmission of Strep pneumoniae?
Droplets or direct contact
Virulence factors of Strep pneumoniae?
Polysaccharide capsule
Clinical infections of Strep pneumoniae?
AOM, meningitis, pneumonia
Vaccine for Strep pneumoniae in adults?
In children?
Pneumovac23 Prenavar 13 (PCV 13)
Moraxella catarrhalis is gram what?
Metabolism?
Habitat?
Negative diplococci
Aerobic
human urt
Clinical infections of moraxalla catarhallis
Otitis media
Other itis’s
Diagnosis of AOM in moraxalla catarhallis?
- Otoscope –> Bulging tympanic membrane
- Puff of air on tympanic membrane to see if it can vibrate
- Tympanometry: measure tone off membrane
Treatment of AOM?
Hold off on antibiotics, aren’t as helpful
COmplications of AOM?
- Permanent damage –> Hearing loss
- Mastoiditis
- Invasive disease
Main antibiotic for AOM?
Amoxicillin
Otitis externa is known as what?
Swimmer’s ear, infection of ear canal
Main causes of otitis externa?
Staph aureus
Candida albicans
Gram-negatives
Acute sinusitis goes for the most amount of time at what?
4 weeks
Bacterial causes of acute sinusitis? 4
S. pneumoniae, H. influenzae, Staph aureus, S. pyogenes
Diagnosis of acute sinusitis? 4
Prolonged rhinitis
Maxillary toothache
Don’t respond to decongestants
Headache/Fever
Treatment for acute sinusitis?
Amoxicillin
What is acute epiglottitis?
Cellulitis and swelling of supraglottic tissue
Is acute epiglottitis serious?
Life threatening –> Can block trachea
Main bacterial causes of acute epiglottitis?
H. influenzae = Most in children
S. pneumoniae, GAS, s. aureus
Diagnosing acute epiglottis? (2)
- Scope
2. X-ray
Treatment of acute epiglottitis? 4
Intubation
Broad spectrum Antibiotics
3rd generation cephalosporin
Steroids
Oral candidiasis is caused by what?
Candida albicans: Fungus that stains gram positive
Habitat of Candida albicans?
Humans (mouths of 25-50%) of healthy people
100% of rectums
Transmission of Candida albicans?
Endogenous: Opportunistic fungal infection
Where does Candida albicans cause disease?
All organs possibly
Treatment of Candida albicans? (2)
- Flucanazole: Attack ergosterol
2. Nystatin: Insert into fungi membrane
Caries is caused by what?
Strep mutants
What percentage of people have strep mutans?
80-90
Three components in development of caries?
- Strep mutans
- Sucrose
- Susceptible tooth enamel
Sucrose is used by strep mutans to form what?
What does this allow for?
Glucose polymer
Bacteria can adhere to enamel
What else does strep mutans ferment?
Result
Sucrose to lactic acid
Demineralize the tooth enamel –> Cavities
Periodontal disease includes what species?
Actinomyces viscosus, actinobacillus, bacteroides
What type of bacteria colonize space between teeth and gingiva?
Anaerobes, gram - and LPS