What's Your Diagnosis? Diphtheria, Pertussis, and Tetanus

Welcome to this month’s What’s Your Diagnosis Challenge!

But before we begin, check to see if you got the previous case on Emergency Department Management of Hematuria in Children correct.

Case Presentation: Diphtheria, Pertussis, and Tetanus: An Update of Evidence-Based Management of Pediatric Patients in the Emergency Department

A local EMS crew rushes in a gurney with a toxic-appearing preschool-aged girl in obvious
respiratory distress…

The parents tell you the girl has had recent congestion and a low-grade fever.
In the ED, the child has a fever of 38ºC, a heart rate of 150 beats/min, a blood pressure of 75/45 mm Hg, and a respiratory rate of 35 breaths/min. On examination, there is inspiratory stridor, significant cervical lymphadenopathy, and a thick, grayish membrane coating the posterior pharynx. Chest examination reveals bilateral rales and tachycardia with frequent ectopic beats.
Could this child have viral myocarditis associated with simple pharyngitis? You page the infectious disease specialist and ask the nurse to institute strict isolation precautions. What tests, if any, should you order to confirm your suspected diagnosis?

Case Conclusion

While preparing for rapid sequence intubation, you informed your subspecialists that this child has
suspected respiratory diphtheria complicated by diphtheric myocarditis. The pediatric infectious disease
team contacted the CDC Emergency Operations Center, which agreed with the preliminary diagnosis
based on clinical signs only, and they urgently dispatched DAT. The child was intubated and received
both antidysrhythmic and inotropic support while the cardiology and PICU teams considered the need
for temporary cardiac pacing. IV erythromycin at 40 mg/kg/day divided over 4 doses was administered,
and the patient was transferred to the PICU, as personnel from the state Health Department arrived and
assumed control of identifying and testing the child’s close contacts.