Summary Microbes: Respiratory Infections

Respiratory Infections
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- respiratory system Streptococcal acute glomerulephritis - complication
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• mucociliary escalator - ciliated mucous membranes from strep
line lower respiratory tract • antibodies accumulate in glomeruli - leads to
- IgA mucus traps pathogens, sweep up to mouth to inflammation
expel • obstuction in blood flow - HTN, low urine output
• alveolar macrophages - phagocytose anything in
lungs >
- diptheria - corynebacterium diphtheriae (gram pos)
• resident microbiota - compete with potential • produce diphtheria toxin
pathogens, some secrete antimicrobial peptides • person to person via respiratory drop/skin
> rhinosinusitis - inflammation of sinuses
- • pseudomembrane from toxin
• generally opportunistic infection by normal - bacteria, dead epithelial cells, immune cells form
microbiota patch in throat
• may be secondary to viral infection, cigarette - can lead to blockage, suffocation
smoke, irritants • bulls neck (swelling)
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- otitis - inflammation of inner ear • if infects blood, cause nerve, heart, kidney
• bacterial infections common in early childhood damage (1/10 die)
• otitis externa (swimmers ear) - infects ear canal, • treatment with antitoxin
commonly caused by psuedomonas, streptococcus, - bacterial pneumonia - streptococcus pneumoniae
staphylococcus (gram pos)
• otitis media - inflammation of middle ear • inflammation of lungs, fluid filled alveoli/
- usually secondary to viral infection, leads to bronchioles
pressure in middle/ear drum (pain, balance loss, fever, HA) • spread from lungs to blood - bacteremia
• usually treated w/ antibiotic ear drops, may require • treat with antibiotics
bilateral myringotomy/tympanostomy tube • haemophilus influenzae - normal respiratory
=> streptococcal pharyngitis (strep throat) - caused by S. microbiota
pyogenes (gram pos) • mycoplasma pneumoniae - walking pneumonia
• if untreated may cause laryngitis, bronchitis • diagnosed by sputum or bronchial lavage
• rapid strep/PCR takes minutes >
- legionnaires disease - legionella pneumophila (gram
• usually treated with penicillin/other beta-lactams (if neg)
allergic, erythromycin) • fastidious organisms - require cysteine, iron salts
• ↳ virulence • fresh water, humid, ventilators, fountains, air
- hyaluronic acid capsule resembles human connective ducts
tissue • transmission through inhalation of aerosolized
- M protein helps with adhesion to host cells, contaminated water
avoiding phagocytosis • live/multiply inside macrophages
> scarlet fever - complication of strep throat, usually under
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Tuberculosis - mycobacterium tuberculosis (gram pos)
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10 YO
• cell wall contain mycotic acids
• only when contains Spe toxin (super antigen) - gains
access to lymph/blood stream - acid fast, slow grower, resist phagocytosis,
intracellular growers, resistant to many antimicrobials
• rash on chest/extremities, strawberry tongue
• person to person via inhalation
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- Rheumatic fever - complication of streptococcal
pharyngitis • virulent infection produce cord factor - strands
of cells, prevent neutrophil movement, toxic to
• chronic inflammation of heart, joints, skin mammalian cells
• autoimmune response • latent infection - remain dormant within
• rheumatic mitral valve - attack on heart muscle macrophages, tubercles (10% reactivate)
fibers
• dissemi nated/extrapulmonary TB - spread
• heart failure/death if untreated through blood to organs