Rosen & Barkin's 5-Minute Emergency Medicine Consult (537 page)

• Catarrhal phase:
  
  • Malaise
    
  • Low-grade fever
    
  • Rhinorrhea
    
  • Sore throat
    
• Paroxysmal phase:
  
  • “Whooping” cough
    
  • Post-tussive cyanosis
    
  • Post-tussive emesis
    
• “Whooping” sound during paroxysmal phase
  
• Catarrhal phase:
  
  • Persistent cough
    

• Catarrhal phase:
  
  • Low-grade fever
    
  • Rhinorrhea
    
  • Lacrimation
    
  • Dry cough (late phase)
    
  • Conjunctival inflammation
    
• Paroxysmal phase:
  
  • Paroxysmal whooping cough
    
• Convalescent phase:
  
  • Occasional paroxysmal cough
    

• The ED diagnosis should be made on clinical grounds
  
• Attempt to establish a history of a contact
  
• Observe the paroxysmal cough with the characteristic whoop
  
• Use ancillary studies to further support the clinical diagnosis and exclude complications
  

• Polymerase chain reaction:
  
  • High sensitivity and specificity
    
  • High sensitivity leads to more false positives
    
  • Best practices for testing with PCR:
    
    • Test only those with symptoms
      
    • Testing after 4 weeks of cough or following antibiotics will increase false negative rate
      
    • Obtain samples via aspiration or posterior nasopharyngeal swab to maximize DNA recovery
      
  • Should be used in conjunction with culture
    
• Direct immunofluorescence assay of nasopharyngeal mucus:
  
  • High false-positive rate
    
• Culture of nasopharynx or cough plate on a Bordet–Gengou medium:
  
  • Takes 7–12 days
    
  • High specificity
    
  • Low sensitivity
    
    • Remains the gold standard test
      
• Serology:
  
  • Useful in later diagnosis
    
  • Perform testing 2--8 weeks after cough onset
    
• WBC count:
  
  • Leukocytosis (20,000–50,000 cells/mm
    ³
    ) with marked lymphocytosis
    
  • Normalizes during convalescent phase
    
  • Elevation of WBC and lymphocytosis parallels severity of cough
    
• Immunofluorescent and enzyme immunoassays to exclude respiratory syncytial virus
  
• Done on either nasal wash or nasopharyngeal swab (Dacron)
  

CXR:

• Most often normal
  
• Perihilar infiltrates
  
• Atelectasis
  
• Occasionally characteristic “shaggy” right heart border
  
• Secondary bacterial pneumonia
  

• Infection:
  
  • Parallel whooping cough syndrome caused by
    Bordetella parapertussis, Chlamydia trachomatis, Chlamydia pneumoniae, Bordetella bronchiseptica
    , or adenovirus
    
  • Pneumonia:
    
    • Bacteria
      
    • Mycoplasma
      
    • Mycobacterium
      
  • Bronchiolitis:
    
    • Respiratory syncytial virus
      
    • Influenza
      
    • Other virus
      
• Reactive airway disease
  
• Foreign body
  
• Cystic fibrosis
  

TREATMENT

• Oxygen
  
• Monitor airway
  
• Suction
  

• Oxygen and respiratory support
  
• Suction mucous plugs
  

• Universal precautions:
  
  • Specifically requires droplet precautions for 5 days after initiation of antimicrobial therapy
    
• Maintenance of adequate hydration
  
• Monitor oxygenation during paroxysms; supplement oxygen
  
• Airway management may be lifesaving in younger children
  
• Antibiotics:
  
  • Effective in the catarrhal stage
    
  • Prevent further transmission in the paroxysmal stage
    
  • Azithromycin is the first-line agent
    
  • Alternatively, clarithromycin, erythromycin, or trimethoprim–sulfamethoxazole may be used, although the efficacy is unproven; useful if erythromycin is not tolerated
    
• Corticosteroids and albuterol may reduce paroxysms of coughing, but further studies are required
  
• With increasing incidence of pertussis among adolescents and adults, emergency physicians can decrease incidence of pertussis by making vaccination routine when also vaccinating against tetanus:
  
  • Tetanus toxoid, reduced diphtheria toxoid, acellular pertussis (Tdap)
    

Bronchodilators and steroids are generally not recommended for pertussis

• Azithromycin (adult): 500 mg PO day 1, then 250 mg PO QD for 4 days
  
• Azithromycin <5 mo: 10 mg/kg PO daily for 5 days
  
• Azithromycin 5 mo–adult: 10 mg/kg PO day 1 (max. 500 mg), then 5 mg/kg PO daily for 4 days (max. 250 mg daily)
  
• Tetanus toxoid, reduced diphtheria toxoid, Tdap vaccine: 0.5 mL IM:
  
  • Adacel: Approved for ages 11 and up
    
  • Boostrix: Approved for ages 10 and up
    

• Advisory Committee on Immunization Practices (ACIP) recommends Tdap for pregnant patients during each pregnancy
  
• May be given anytime, but preference is between 27--36 weeks gestation
  

• Clarithromycin: 15 mg/kg/d div. BID for 7 days (max. 1 g/d)
  
• Erythromycin: 40–50 mg/kg/d div. QID for 14 days (max. 2 g/d). Associated with risk of pyloric stenosis when administered in 1st 2 wk of life
  
• Trimethoprim–sulfamethoxazole: 8/40 mg/kg/d div. BID for 14 days (max. 320/1,600 mg/d):
  
  • Not for infants <2 mo
    

FOLLOW-UP

• Patients <1 yr
  
• Apnea
  
• Cyanosis during paroxysms of cough
  
• Significant associated pneumonia
  
• Encephalitis
  

• Children without apnea, respiratory compromise, altered mental status, or complications and respiratory distress
  
• Warm liquids to reduce coughing spasm
  
• Remove thick secretions with bulb suction in infants
  
• Good hydration
  
• Avoid cough triggers: Cigarette smoke, pollutants, perfumes
  
• Postexposure prophylaxis is recommended to all persons with close contact (within 3 ft of a symptomatic person):
  
  • Antibiotic recommendations are the same as those with disease
    
  • Symptomatic children should be excluded from school or work; individuals with pertussis may return after 5 days of full treatment
    

Children who are discharged need close follow-up to monitor hydration status and for respiratory compromise.

• Head, eyes, ears, neck, throat:
  
  • Epistaxis
    
  • Subconjunctival hemorrhage
    
• Respiratory:
  
  • Acute respiratory arrest
    
  • Pneumonia caused by secondary infection
    
  • Pneumothorax
    
  • SC or mediastinal emphysema with crepitus
    
  • Bronchiectasis
    
• GI:
  
  • Hernia: Inguinal or abdominal
    
  • Rectal prolapse
    
• Neurologic:
  
  • Seizures
    
  • Encephalitis
    
  • Coma
    
  • Intracranial hemorrhage
    
  • Spinal epidural hemorrhage
    

• Infants ≤1 yr need admission for pertussis
  
• Tdap should be given to eligible patients requiring tetanus prophylaxis
  
• Droplet precautions should be implemented for 5 days after implementation of effective antimicrobial therapy
  
• Chemoprophylaxis is recommended for all household contacts irrespective of age and immunization status
  

• Centers for Disease Control and Prevention. Pertussis (Whooping Cough); Best Practice for Health Care Professionals on the use of Polymerase Chain Reaction (PCR) for Diagnosing Pertussis. Available at:
  http://www.cdc.gov/pertussis/clinical/diagnostic-testing/diagnosis-pcr-bestpractices.html
  .
  
• Centers for Disease Control and Prevention. Pertussis (Whooping Cough); Diagnosis Confirmation. Available at:
  http://www.cdc.gov/pertussis/clinical/diagnostic-testing/diagnosis-confirmation.html
  .
  
• Centers for Disease Control and Prevention. Updated recommendation for use of tetanus toxoid, reduced diptheria toxoid, and acellular Pertussis (Tdap) vaccine in adults aged 65 years and older -- Advisory Committee on Immunization Practices (ACIP), 2012.
  MMWR
  . 2012;61:468--470.
  
• Centers for Disease Control and Prevention. Updated recommendation for use of tetanus toxoid, reduced diptheria toxoid, and acellular Pertussis (Tdap) vaccine in pregnant women -- Advisory Committee on Immunization Practices (ACIP), 2012.
  MMWR
  . 2013;62:131--135.
  
• Gregory DS. Pertussis: A disease affecting all ages.
  Am Fam Physician
  . 2006;74:420–426.
  
• Klein NP, Bartlett J, Rowhani-Rahbar A, et al. Waning protection after firth dose of acellular pertussis vaccine in children.
  N Engl J Med.
  2012;367:1012--1019.
  
• McIntyre P, Wood W. Pertussis in early infancy: Disease burden and preventive strategies.
  Curr Opin Infect Dis
  . 2009;22:215–223.
  
• Shah S, Sharieff GQ. Pediatric respiratory infections.
  Emerg Med Clin North Am
  . 2007;25:961–979.
  
• Wood N, McIntyre P. Pertussis: Review of epidemiology, diagnosis, management and prevention.
  Paediatr Respir Rev
  . 2008;9:201–211.
  

CODES