Download A Bordering Cough

A Bordering Cough
A Case Study about Bordetella persussis
by Janell Jones
Patient History
 A 6 year old boy with
a persistent cough
for 2 weeks
 During the last 2
days he experienced
vomiting after severe
coughing episodes
Laboratory Findings
 Gram stain of
sputum revealed
small gram negative
bacilli
 No growth on routine
blood agar
 After 5 days, growth
was recovered on
Regan-Lowe agar
Gram Stain photo
www.vaccineinformation.org/photos/pertcdc001a.jpg
Courtesy of Centers for Disease Control and Prevention
Diagnosis
Bordetella pertussis
AKA
Whooping Cough
Bordetella pertussis
 B. pertussis produces disease only in
humans
 Pertussis is a highly contagious, acute
infection of the upper respiratory tract
 Infection is transmitted from person to
person by direct contact or airborne
droplets
 Prior to mass immunization, an
estimated 95 percent of people
contracted Pertussis during their life time
Symptoms
 Initially, symptoms resemble those of a
common cold (sneezing, runny nose, mild
cough)
 Within two weeks, the cough becomes more
sever and violent, coughing associated with
vomiting and a characteristic intake of breathe
that sounds like a “whoop”.
 Between these attacks of coughing the
individuals appears and feels perfectly well
 Whooping cough lasts at least 3 weeks and can
go on for 3 months or even longer
 Listen to a pertussis cough at this web
site
http://www.immunizationed.org/pertus.asp
Complications
 Middle ear infections
 Dehydration
 Pneumonia
 Convulsions (seizures)
 Brain damage from lack of oxygen
 Brief episodes of stopped breathing
Pathogenesis
 The bacteria enter the mouth or nasopharynx




as aerosols
The bacteria binds to ciliated cells in the
respiratory mucosa
B. pertussis produces a number of adhesins
which aid in its ability to colonize
B. pertussis produces only localized infections
Pertussis causes about 300,000 deaths/year in
un-immunized populations in the world
Who is at risk?
 Newborns until they have had their primary
whooping cough shots
 Children who have not been immunized
 People over 10 years old but more likely over
50 whose immunization is wearing off
 The over 50’s who never had the chance of
immunization but never got the natural infection
as children
Cultivation
 B. pertussis is fastidious (it doesn’t grow on
typical blood agar)
 Growth after 3-5 days at 35oC in a humidified
atmosphere without elevated carbon dioxide on
Regan-Lowe medium
 Regan-Lower is a charcoal agar with 10%
horse blood and cephalexin antibiotic
 It appears as small, smooth shiny colonies with
a pearl-like luster resembling mercury droplets
surrounded by a zone of hemolysis
Laboratory Identification
 Faintly-staining small gram-negative
bacilli on Gram stain
 A strict aerobe that is nonfermentative
and nonmotile
 Catalse and Oxidase positive
 Nitrate, Citrate and Urease negative
 Specimens are sent to the state health
department for confirmation
Treatment
 For the average case of whooping cough, there
is no treatment likely to make a difference to the
course of the illness or materially reduce the
symptoms
 However, treatment of cases with certain
antibiotics such as erythromycin can shorten
the contagious period (1st stage of the disease)
 Since diagnosis seldom occurs during this time,
antibiotic therapy is usually ineffective at
decreasing the length of the illness
Prevention
 The single most effective control
measure is maintaining the highest
possible level of immunization in the
community
 A child needs five DTP shots (Diptheria,
Tetanus, Pertussis) at 2, 4, 6 and 15
months of age followed by a booster at
4-6 years for complete protection
 People with Pertussis should stay away
from infants and young children
Case Summary
 6 year boy diagnosed with whooping
cough
 No antibiotics given
 Mother was advised to used a humidifier,
encourage drinking plenty of fluids, and
to return to ER if he had difficulty
breathing
References
 Pertussis, CDC Public Health Image Library,
http://phil.cdc.gov/phil/results.asp, Last
accessed on 11/08/04.
Credits
This case was prepared
by
Janell Jones, MT(ASCP)
while she was a
Medical Technology
student in the
2004 MT Class at
William Beaumont
Hospital,
Royal Oak, MI.