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A. Organismnavigator

  1. Bordetella pertussis or (less commonly) B. parapertussis
  2. Fastidious Gram negative rod
  3. Lives in tracheobronchial tree
  4. Culture requires selective media
  5. Virulence factors
    1. Pertussis toxin
    2. Tracheal cytotoxin
    3. Pili
    4. Fillamentous hemagglutinin
  6. No animal reservoir
  7. Both children and adults susceptible to organism
  8. In 2003, 11,647 cases of pertussis reported in USA
  9. Worldwide, >300,000 deaths annually in children, mainly in underdeveloped nations

B. Pathogenesis navigator

  1. B. pertussis produces one major specific toxin
  2. This toxin is an enzyme that catalyzes ADP-ribose attachment to a G-protein
  3. Thus, ADP-ribose is attached to a cysteine in the C-terminus of G(i)alpha protein
  4. This leads to inhibition of receptors coupled to the G(i)alpha protein
  5. Unclear how this inhibition actually leads to symptoms
  6. Likely, however, that inhibited signalling leads to excess mucous production, irritation

C. Phases of Illnessnavigator

  1. Catarrhal Phase 1-2 weeks
    1. Mild cough
    2. 1-2 weeks rhinorrhea
    3. Conjunctivitis
  2. Paroxysmal Phase 2-4 weeks
    1. Cough, paroxysms usually with "whoop"
    2. Inspiratory wheezing
    3. Conjunctival Hemorrhage
    4. Lymphocytosis
  3. Convalescent Phase - slow resolution of symptoms
  4. In adults, chronic cough may be the major (or only) symptom of infection
  5. Increasing incidence in adult population, particularly in patients with cough >2 weeks [3]

D. Complicated Diseasenavigator

  1. Failure to thrive
  2. Vomiting
  3. Atelectasis and frank pneumonia
  4. CNS - hyperinsulinemia, decreased glucose, seizures, hypoxemia

E. Differential Diagnosisnavigator

  1. Refractory Cough Syndromes
  2. Adenovirus Infection
  3. Mycoplasma Infection

F. Diagnosisnavigator

  1. Clinical Presentation
    1. Consider risk for exposure
    2. Vaccinated persons, older children, adults, may have simple (not "whooping") cough
  2. Culture
    1. Gold standard within 3 weeks of onset of cough
    2. Use sputum, bronchoalveolar lavage fluid
    3. Relatively insensitive
  3. Nasopharyngeal swab on calcium alginate tip - notify lab to look for pertussis
  4. Acute and Convalescent Serology
    1. Pertussis Toxin Antibody
    2. Antibody to Filamentous Hemagglutinin
    3. ELISA - elevated (acute) IgG levels, particularly in setting of chronic cough
  5. Polymerase chain reaction (PCR) - within 3 weeks of cough onset; some false positives
  6. Combinations of diagnostic tests are usually used

G. Treatment navigator

  1. Macrolides are first line
    1. Erythromycin is active against organism, 500mg po or iv q6 hours x 7 days
    2. Azithromycin 10mg/kg (maximum 500mg) x 1, then 5mg/kg (maximum 250mg) qd x 4
    3. Clarithromycin 10mg/kg (maximum 500mg) bid x 7 days
  2. Doxycycline 100mg po bid (or iv) is also effective
  3. Trimethoprim/sulfamethoxazole (TMP/SMX) bid x 7 days also effective
  4. Ampicillin does not clear the organism from the respiratory tract
  5. Treatment is instituted in patients with up to 3-4 weeks of cough (but not longer)

H. Vaccination navigator

  1. Original Vaccine
    1. Killed whole bacterial cells
    2. Causes local and systemic reactions in high proportion of vaccine recipients
    3. Used in adults only in outbreaks (generally avoided due to severe reactions)
  2. Acellular Vaccine
    1. New, acellular vaccine (aP) is very effective (>70%) with few side effects [4,5]
    2. Vaccine efficacy after household exposure was >75% and well tolerated [6]
    3. Can be given to adults with minimal reactions
    4. Five-component vaccine is great improvement 3 component and whole-cell vaccines [7]
    5. Two component vaccines are less effective than 5 component vaccines [5]
    6. Tricomponent acellular pertussis vaccine is effective in 92% of adolescents and adults [9]
    7. Combination DTaP is available and all Td boosters should be replaced with TDaP [10]
    8. Specific booster versions of DTaP are now available (Adacel®, Boostrix®) [10]
  3. Increasing incidence of disease suggests need for booster in adults with acellular vaccine
  4. Combined Tetanus/Diphtheria/Pertussis (5 component) Vaccine (Tdap) [8]
    1. Increasing reports of pertussis in adults have driven this combination vaccine
    2. 94% of volunteers vaccinees with Tdap have protective antibody concentrations
    3. Similar incidence of local and systemic reactions with Td versus Tdap vaccines
  5. Bordetella infections can occur in immunized populations
  6. Bordetella parapertussis may be increasing in populations immunized to B. pertussis

References navigator

  1. Hewlett EL and Edwards KM. 2005. NEJM. 352(12):1215 abstract
  2. Crowcroft NS and Pebody RG. 2006. Lancet. 367(9526):1926 abstract
  3. Nennig ME, Shinefield HR, Edwards KM, et al. 1996. JAMA. 275(21):1672 abstract
  4. Greco D, Salmaso S, Mastrantonio P, et al. 1996. NEJM. 334(6):341 abstract
  5. Gustafsson L, Hallander HO, Olin P, et al. 1996. NEJM. 334(6):349 abstract
  6. Schmitt HJ, von Konig CHW, Neiss A, et al. 1996. JAMA. 275(1):37 abstract
  7. Olin P, Rasmussen F, Gustafsson L, et al. 1997. Lancet. 350(9090):1569
  8. Pichichero ME, Rennels MB, Edwards KM, et al. 2005. 293(24):3003 abstract
  9. Ward JI, Cherry JD, Chang SJ, et al. 2005. NEJM. 353(15):1555 abstract
  10. TDaP Vaccines for Adolescents and Adults. 2006. Med Let. 48(1226):5 abstract