Q- A 5-month-old boy is brought to the clinic by his mother because of a 10-day history of “coughing spells” that occur several times daily and last 1 to 2 minutes; he often vomits afterward. He was delivered at term to a 16-year-old patient, gravida 1, para 1, following an uncomplicated pregnancy and spontaneous vaginal delivery in Mexico. His parents immigrated to the USA shortly after his birth. He has no history of major medical illness and receives no medications. He has never been to a physician for a well-child examination and has not received any vaccinations. He appears well. Vital signs, including oxygen saturation, are within normal limits. During the physical examination, he coughs uncontrollably for 2 minutes, after which there is a gasping sound and subsequent vomiting. Afterward, he appears exhausted. Physical examination shows no nasal flaring or intercostal or subcostal retractions. The lungs are clear; no wheezes or crackles are heard.
A drug from which of the following classes is most appropriate for this patient?
(A) Cephalosporin
(B) Fluoroquinolone
(C) Macrolide
(D) Penicillin
(E) Sulfonamide
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Answer and Explanation
This is a typical case of pertussis (whooping cough) caused by Bordetella pertussis. It is characterized by severe coughing fits and post-tussive vomiting. The patient is unvaccinated, which increases the risk of infection.
The drug of choice for Bordetella pertussis is a macrolide antibiotic (azithromycin, clarithromycin, or erythromycin).
The correct answer is C