CASE HISTORY Will,a Formerly Rambunctious Five-Year-Old from San Francisco,was Taken to the to the Emergency

Essay

CASE HISTORY
Will,a formerly rambunctious five-year-old from San Francisco,was taken to the emergency department after having a severe cough for two weeks.His illness started as a runny nose,dry cough,and low-grade fever.But within days the coughing would come in violent fits lasting up to one minute (called a paroxysm).The nurse practitioner attending Will observed one of these fits.Unable to breathe between coughs,the boy became cyanotic (turned blue).When the staccato of coughs finally ended,Will gasped,desperate for breath.The air rushing to fill his lungs made an ear-piercing whooping sound.This telltale "whoop" led the nurse practitioner to suspect whooping cough,a disease highly contagious in its early stages.In the later stages (greater than four weeks)the patient is no longer contagious because the bacterial agent,Bordetella pertussis,has succumbed to the immune response.However,the telltale cough will persist for weeks while the lungs repair the damage caused by the pertussis toxins.The nurse practitioner,now wearing a mask,took a nasopharyngeal swab sample for bacteriological culture and prescribed the antibiotic azithromycin (a member of the macrolide class of antibiotics that inhibit protein synthesis).Because the organism takes so long to grow in the laboratory (5-12 days)and because the organism is hard to find late in the disease,a blood sample was also drawn to test for anti-B.pertussis immunoglobulin a antibody.By the next day the serum test was positive for B.pertussis antibodies.The pathogen eventually also grew in the culture.Despite extensive efforts at vaccination,more than 41,000 cases of whooping cough were reported in the United States in 2012.
As a Gram-negative bacterium,Bordetella pertussis produces endotoxin.Why is this toxin not a major contributor to the disease signs and symptoms associated with pertussis?