CASE BASED REVIEW OF MEDICAL MICROBIOLOGY
Bordetella pertussis
Dr Tadayo Hashimoto M.D.
Professor
Department of Microbiology & Immunology
Jerry, a 7 month old child, was brought to your clinic with a running nose, sneezing, and slight irritability. Her mother said that Jerry was healthy and was running around until several days ago. No specific treatment was initiated for this "mild cold". Two weeks later, her mother returns because the child had a cyanotic (turned blue) episode during a coughing spell. She indicates that the cough appears to be worsening, particularly at night. It often comes in spasms and she hears "whooping" sound after a coughing spell and he frequently vomits after coughing.
On examination, Jerry appears mildly dehydrated but not distressed. His body temperature is 37.2° C. His chest is clear and his abdominal examination is normal. A full blood count reveals leucocytosis and a marked
lymphocytosis.
- What is your initial diagnosis of this child? What additional
information do you need for making the diagnosis more definitive?
- Jerry has no record of DPT vaccination. Mother indicates that
Jerry did not receive DPT (Diphtheria, Pertussis and Tetanus)
vaccine because there was a family history of epilepsy in the
maternal uncle.
What is your diagnosis based on the information available at this
point?
- How can you confirm your diagnosis?
- What are the clinical symptoms of a typical case of whooping
cough?
- Is whooping cough communicable?
- How is whooping cough acquired or transmitted from person
to person?
- How is B. pertussis characterized microbiologically?
What cautions are necessary for successful culturing of B.
pertussis form patients?
- What make B. pertussis pathogenic to humans?
- What is pertussis toxin (PT)? What is its mode of action?
- Why does B. pertussis produce various toxins
or virulence factors only when it enters the human host?
- Correlate the progression of the disease and the characteristic
clinical symptoms of whooping cough with virulence factors of
B. pertussis.
- How do you treat whooping cough?
- How do you prevent this disease?
- What is the major problem that may results from the use of
pertussis vaccine?
- Is whooping cough childhood disease?
- Reference:
Sherris Medical Microbiolog 3rd ed. pp. 366 - 371, Appleton
and Lange, 1994
Harrison's Principle of internal medicine
Bacterial pathogenesis by Abigale A. Sayer and Dixie D. Whitt,
ASM Press, 1994
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