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Respiratory Pathogens

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Updated 2007-03-11 15:18

Associated Diseases

PathogenAssociated Diseases
Streptococcus pyogenes (Group A)Pharyngitis; Scarlet Fever; Rheumatic Fever (resp infxn); Acute Glomerulonephritis (skin or resp infxn)
Haemophilus influenzaeChildren: URTI (epiglottitis, otitis media, sinusitis); Adults & children: Pneumonia, Meningitis
Corynebacterium diphtheriaeDiphtheria (grayish pseudomembranes over tonsils- airway obstruction, bull neck, laryngeal nerve palsy)
SARS-CoVI: Fever Prodrome, II:Respiratory Phase dry cough, hypoxia pneumonia
Bordetella pertussisWhooping Cough (cough w/ inspiratory whoop, "cough of 100 days")
Moraxella catarrhalisURI: otitis media, sinusitis (#3), bronchitis (in those with COPD), conjuctivitis, Pneumonia (often secondary to influenza)
Influenza virus (types A, B, C)Influenza (winter): epidemics (A), outbreaks (B), mild infxns (C)
Rhinoviruscommon cold (coryza) in fall and winter
Coronavirus5-10% of common cold (coryza)
Enterovirussummer cold
AdenovirusURI: acute febrile pharyngitis, atypical pneumonia, epidemic kerato-conjunctivitis
Respiratory Syncytial Virus (RSV)bronchiolitis symptoms, viral pneumonia, tracheobronchitis, Croup
Parainfluenza virusCroup (barking cough, inspiratory stridor, winter peak), Pneumonia, URI
Mumps virusMumps: parotitis, oorchitis, meningitis
Streptococcus pneumoniae (pneumococcus)Adults: Pneumonia, Meningitis; Children: Otitis Media; Sepsis Sinusitis
Staphylococcus aureusPneumonia (in addition to many other dz's), MRSA: Fulminant necrotising pneumonia
Legionella pneumophilaAtypical pneumonia: "Legionaire's dz" an atypical pneumonia characterized by high fever & nonproductive cough
Klebsiella pneumoniaePneumonia (currant jelly sputum often in alcoholics), Nosocomial Pneumonia
Pseudomonas aeruginosaNosocomial Pneumonia common in cystic fibrosis
Burkholderia cepaciaFulminant pneumonia in cystic fibrosis patients
Mycoplasma pneumoniaeAtypical Pneumonia (peak age 10-15 yo) spread within families "Walking Pneumonia"
Mycobacterium tuberculosistuberculosis; assoc w/ poverty, crowding, HIV; granulomas
Chlamydia PneumoniaeAtypical Pneumonia, Pharyngitis, Cough
Mycobacterium aviumintracellulare complex (MAC)opportunistic infx associated late HIV w/ <50 CD4
Candida albicansThrush, Esophagitis (as well as many other dz)
Coccidioides immitis"Valley Fever," flu-like with pulmonary infiltrates, erythema nodosum
Histoplama capsulatumHistoplasmosis: asymptomatic usually, diffuse pneumonia as opportunistic infx
Blastomyces dermatitidisBlastomycosis: Primary pneumonia, dissemination
Cryptococcus neoformansCryptococcosis: self-limiting pneumonia, opportunistic meningitis
Aspergillus fumigatusLung infxns: Allergic aspergillosis, Farmer's Lung, Aspergilloma (Fungus Ball)
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Transmission

PathogenTransmission
Streptococcus pyogenes (Group A)respiratory; direct mucosal contact
Haemophilus influenzaerespiratory
Corynebacterium diphtheriaerespiratory; skin
SARS-CoVrespiratory
Bordetella pertussisrespiratory
Moraxella catarrhalisnormal respiratory flora
Influenza virus (types A, B, C)respiratory & direct contact
Rhinovirusrespiratory & nasal secretions from hand to nose or eye
Coronavirushand to mucous membrane
Enterovirusfecal oral
Adenovirusrespiratory, fecal oral
Respiratory Syncytial Virus (RSV)secretions, fomites, nosocomial infection, reinfection
Parainfluenza virussmall aerosol particles
Mumps virusrespiratory
Streptococcus pneumoniae (pneumococcus)normal flora of oropharynx
Staphylococcus aureusubiquitous in environment, normal flora
Legionella pneumophilarespiratory from environ water sources (air conditioners)
Klebsiella pneumoniaeaerosol, normal flora of large intestine
Pseudomonas aeruginosaubiquitous in moist environment
Burkholderia cepaciaubiquitous in moist environment
Mycoplasma pneumoniaerespiratory (community acquired)
Mycobacterium tuberculosisrespiratory
Chlamydia Pneumoniaerespiratory
Mycobacterium aviumintracellulare complex (MAC)ubiquitous in environment
Candida albicansnormal flora of GI, oral cavity, female genital tract
Coccidioides immitisrespiratory, inhaled arthrospores
Histoplama capsulatumrespiratory, inhaled microconidia spores
Blastomyces dermatitidisrespiratory, inhaled conidia
Cryptococcus neoformansrespiratory, inhaled yeast
Aspergillus fumigatusubiquitous in environment
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Microbe Characteristics/Virulence

PathogenMicrobe Characteristics/Virulence
Streptococcus pyogenes (Group A)gram+ cocci, Beta hemolytic, Group A; Streptokinase, Hyaluronidase, Pyrogenic exotoxins (superantigens), Streptolysin O & S, Streptodornase
Haemophilus influenzaesmall gram- rod; Polysacharide capsule type b, IgA protease, Adherence factors
Corynebacterium diphtheriaeclub shaped gram+ rod arranged in palisades with metachromatic granules (Chinese characters); Diphtheria Toxin (AB)
SARS-CoVCoronavirus family: ss+ RNA, linear, enveloped, helical
Bordetella pertussissmall encapsulated gram- rod; polysaccharide capsule, pili for attachment, Pertussis Toxin (does not invade)
Moraxella catarrhalisgram- cocci, aerobic, oxidase+ catalase-; produces beta-lactamase
Influenza virus (types A, B, C)Orthomyxovirus family: segmented ss- RNA, enveloped, linear; HA, NA
RhinovirusPicornavirus: ss+ RNA, linear, naked; acid-labile; prefers cold; ICAM-1
CoronavirusCoronavirus family: ss+ RNA, linear, enveloped, helical; club shaped surface spikes (peplomers)
EnterovirusPicornavirus family: ss+ RNA, linear, maked; multiple serotypes
AdenovirusAdenovirus family: ds DNA, nonsegmented, naked
Respiratory Syncytial Virus (RSV)Paramyxovirus family: ss-RNA, linear, enveloped; F (fusion) & G (attachment) proteins: cell to cell transfer down respiratory tract causing necrosis of epithelium, edema, plugging, air trapping (resp dx of infancy and elderly)
Parainfluenza virusParamyxovirus family: ss-RNA, linear, enveloped; combined Hemagglutinin/neuraminidase
Mumps virusParamyxovirus family: ss-RNA, linear, enveloped; HA/NA, glycoprotein surfaces spikes
Streptococcus pneumoniae (pneumococcus)gram+ cocci in pairs (diplococci); Alpha hemolytic
Staphylococcus aureusgram+ cocci, nonmotile, non-spore forming, facultative anaerobes (grape like clusters); Protein A, enzymes, exotoxins
Legionella pneumophilarod staining faintly gram- (can't see); beta lactamase
Klebsiella pneumoniaegram- rod with VERY thick capsule; septic shock caused by endotoxins in cell wall
Pseudomonas aeruginosagram- rod, strict aerobe; flagella, pili, binding lectins, mucoid exopolysacharides, exoenzyme S
Burkholderia cepaciagram- rod
Mycoplasma pneumoniaeno cell wall, pleomorphic, very small, polarized; no toxins but instead P1 protein that adheres and causes necrosis of resp tract
Mycobacterium tuberculosisobligate aerobic bacilli; intracellular; virulence factor = cord factor, sulfolipids
Chlamydia Pneumoniaeobligate intracellular pathogen TWAR strain
Mycobacterium aviumintracellulare complex (MAC)acid fast, slow growing
Candida albicanssingle-celled yeast, "pseudohyphae"; proteinase that digests epith cells
Coccidioides immitisdimorphic, forms spheruled filled with endospores that disseminate and induce granulomas
Histoplama capsulatumdimorphic, multiplies within macrophages and forms granulomas
Blastomyces dermatitidisdimorphic; round, double wall, single broad based yeast bud
Cryptococcus neoformansyeast form only, single budding with thick capsule
Aspergillus fumigatusmold form only, acute branching septate hyphae; very fast growing
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Diagnosis

PathogenDiagnosis
Streptococcus pyogenes (Group A)gram stain, Beta hemolytic culture but also bacitracin sensitive
Haemophilus influenzaeSpecial chocolate agar culture w/ factors X (hemin) & V (NAD)
Corynebacterium diphtheriaemorphology and metachromatic staining pattern on tellurite plate cultures or Loeffler's medium
SARS-CoVRT-PCR & serological test
Bordetella pertussisculture with Bordet-Gengou agar
Moraxella catarrhalisnon performed (?)
Influenza virus (types A, B, C)clinical diagnosis; immunofluorescnent staining of viral culture
Rhinovirusnon performed
Coronavirusnon performed
Enterovirusnon performed
Adenovirusnon performed
Respiratory Syncytial Virus (RSV)nasal wash specimens for culture; IFA, ELISA
Parainfluenza virusviral isolation is "gold standard"
Mumps virusnon performed
Streptococcus pneumoniae (pneumococcus)gram stain, Alpha hemolytic, does not grow culture in presence of bile or optochin
Staphylococcus aureusgrapelike clusters of cocci, coagulase+, catalase+
Legionella pneumophilaculture, special agar, serology, fluorescent tests
Klebsiella pneumoniaelarge on gram stain due to capsule, lactose-fermenting
Pseudomonas aeruginosagram stain, motile, ferments lactose
Burkholderia cepacia"similar to P. aeruginosa"
Mycoplasma pneumoniaeno gram stain, cold agglutination test, slow special agar (fried eggs on culture)
Mycobacterium tuberculosisacid-fast; grows with standard culture media; catalase-
Chlamydia Pneumoniaedoesn't gram stain
Mycobacterium aviumintracellulare complex (MAC)acid-fast
Candida albicansepithelium scrapins examed with KOH prep, Sabouraud's agar Germ Tube Test Positive
Coccidioides immitisbiopsy, Sabouraud's agar
Histoplama capsulatumbiopsy, Sabouraud's agar, Ag serology of urine
Blastomyces dermatitidisbiopsy Sabouraud's agar
Cryptococcus neoformansculture, yeast cells in CSF when mixed on India ink stain, capsular antigen test
Aspergillus fumigatusbiopsy, culture, silver stains to ID
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Vaccines

PathogenVaccines
Streptococcus pyogenes (Group A)none (over 70 serotypes)
Haemophilus influenzaevaccine (capsular antigen) against type B
Corynebacterium diphtheriaeDiphtheria toxoid vaccine (part of DPT)
SARS-CoVnone
Bordetella pertussispart of DPT vaccine
Moraxella catarrhalisVaccine under development
Influenza virus (types A, B, C)inactivated trivalent annual vaccine, Intranasal vaccine for ages 5-49 (not immunosupp.)
Rhinovirusnone (over 100 serotypes)
Coronavirusnone
Enterovirusnone
Adenovirusenteric-coated live nonattenuated vaccine for military
Respiratory Syncytial Virus (RSV)none
Parainfluenza virusnone
Mumps viruslive, attenuated as part of MMR
Streptococcus pneumoniae (pneumococcus)(over 65 yo or immunocompromised) w/23 of most common capsular antigens
Staphylococcus aureusnone
Legionella pneumophilanone
Klebsiella pneumoniaenone
Pseudomonas aeruginosanone
Burkholderia cepacianone
Mycoplasma pneumoniaenone
Mycobacterium tuberculosisBCG (low efficacy)
Chlamydia Pneumoniaenone
Mycobacterium aviumintracellulare complex (MAC)none
Candida albicansnone
Coccidioides immitisnone
Histoplama capsulatumnone
Blastomyces dermatitidisnone
Cryptococcus neoformansnone
Aspergillus fumigatusnone
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Treatment

PathogenTreatment
Streptococcus pyogenes (Group A)Penicillin
Haemophilus influenzaeURI: Ampicillin; Prophylaxis: Rifampin
Corynebacterium diphtheriaeantitoxin; Erythromycin
SARS-CoVsupportive, possible ventilation
Bordetella pertussisErythromycin, supportive therapy
Moraxella catarrhalisAmoxicillin/clavulanate
Influenza virus (types A, B, C)supportive; Uncoating inhibitors (inf. A only): Amantadine Rimantadine Neuraminidase inhibitors (Inf. A+B): Zanamivir, Oseltamivir phosphate
Rhinovirussymptomatic, self-limited
Coronavirussymptomatic, self-limited
Enterovirussymptomatic, self-limited
Adenovirussymptomatic
Respiratory Syncytial Virus (RSV)supportive: oxygen, fluid control, steroids, ventilations; ribavirin (controversial)
Parainfluenza virussupportive
Mumps virussupportive
Streptococcus pneumoniae (pneumococcus)Penicillin G
Staphylococcus aureusMethicillin, Nafcilin (Penicillin resistant); MRSA (vancomysin or linezolid)
Legionella pneumophilaMacrolide antibiotics, Rifampin (resistant to beta lactam antibiotics)
Klebsiella pneumoniaeTreatment dilemmas due to high antibiotic resistance
Pseudomonas aeruginosa3rd generation cephalosporins
Burkholderia cepacia3rd generation cephalosporins
Mycoplasma pneumoniaeErythromycin or Tetracyclin
Mycobacterium tuberculosismulti-drug regimen (including INH, RIF, and pyrazinamide); Quantiferon (new)
Chlamydia PneumoniaeErythromycin
Mycobacterium aviumintracellulare complex (MAC)extremely resistant, 4-8 drug combo
Candida albicansAmphotericin B, fluctyosine, azoles, echinocandins
Coccidioides immitisAmphotericin B, azoles
Histoplama capsulatumItraconazole, Fluconazole, Amphotericin B (if severe)
Blastomyces dermatitidisItraconazole, Ketoconazole, Amphotericin B
Cryptococcus neoformansAmphotericin B, itraconazole
Aspergillus fumigatussurgical removal of fungus ball Voriconazole Amphotericin Caspofungin
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Notes

PathogenNotes
Streptococcus pyogenes (Group A)Scarlet fever, Rheumatic fever, Glomeruloneph.
Haemophilus influenzaeepiglottitis, potential emergency!
Corynebacterium diphtheriae"Chinese characters," gray pseudomemb.
SARS-CoVfirst reported in Asia 2/2003
Bordetella pertussiscough of 100 days
Moraxella catarrhalisotitis media, sinusitis
Influenza virus (types A, B, C)genetic drift (epidemics), gentic shift (pandemics)
Rhinovirus50% of common colds
Coronavirusdiarrhea in infants
Enterovirussummer colds
Adenovirusoutbreaks among millitary recruits
Respiratory Syncytial Virus (RSV)annual outbreaks in babies, respiratory distress & tachypnea
Parainfluenza virusstridor, potential emergency!, "seal bark" cough
Mumps virusswollen parotid glands
Streptococcus pneumoniae (pneumococcus)#1 community acquired pneumonia
Staphylococcus aureuscoagulase+
Legionella pneumophilaair conditioners
Klebsiella pneumoniaethick capsue, alcoholics via aspiration, "currant jelly" suptum
Pseudomonas aeruginosapneumonia in cystic fibrosis patients
Burkholderia cepacianone
Mycoplasma pneumoniae"walking" pneumonia, young adults, spread among families
Mycobacterium tuberculosisPPD test, multi-drug resistance, chest X-ray, poverty
Chlamydia PneumoniaeExcellent prognosis in young patients, 5-10% mortality in elderly
Mycobacterium aviumintracellulare complex (MAC)opportunistic infx in HIV patients
Candida albicansimmunocompro.
Coccidioides immitisdeserts & SW US, Filipinos & Asians with predisposition
Histoplama capsulatumMississippi & Ohio River valleys, bat & bird droppings
Blastomyces dermatitidisCentral/Easter USA, soil with decay
Cryptococcus neoformansOpportunistic infx in 10% of HIV patients, pigeon droppings
Aspergillus fumigatusFungus balls
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