a COPD, chronic obstructive pulmonary disease.
b CF, cystic fibrosis.
c dsDNA, double-stranded DNA.
d ssRNA, single-stranded RNA.
e SARS-CoV, severe acute respiratory syndrome coronavirus.
f MERS-CoV, Middle East respiratory syndrome coronavirus.
CASE 7
The patient was a 5-year-old male who awoke on the day prior to evaluation with a sore throat and fever. His mother had him stay home from kindergarten and treated him symptomatically with Tylenol. He slept well but the next day awoke still complaining of sore throat and fever, as well as headache and abdominal pain. He was an only child and neither parent was ill.
On physical examination, he was noted to have a fever of 38.4°C. His physical examination was significant for a 2+ (on a scale of 1 to 4+) red anterior pharynx, tonsillar region, and soft palate. His anterior cervical lymph nodes at the angle of the mandible were slightly enlarged and tender. No skin lesions or rashes were seen. He did not have a cough, runny nose, or conjunctivitis. A rapid antigen test for group A streptococci (GAS) and a positive and negative control of the assay are seen in Fig. 7.1. When the results of the rapid antigen test were known, the patient was given a 10-day course of oral amoxicillin.
1 1. Based on his clinical presentation, what organism was most likely causing this patient’s infection? What does the rapid strep antigen test tell you?
2 2. Was antimicrobial therapy necessary in this patient? Explain.
3 3. This patient was at risk for two noninfectious sequelae. What are they? Briefly describe our current understanding of the pathogenesis of these two disease processes.
4 4. What antimicrobial resistance problems have been observed with this organism?
5 5. Sore throat associated with a maculopapular rash is frequently seen with this organism. What is this usually benign condition called? What virulence factor is believed to be responsible for production of this rash?
6 6. What is the current status of vaccine development for this organism?
CASE 7 CASE DISCUSSION
1. Based on a GAS clinical prediction scoring system developed at the University of Virginia and validated in both adults and children, this patient scored positive for all the criteria: temperature of >38°C, no cough, tender anterior cervical lymphadenopathy, tonsillar swelling and exudates, and age 3 to 14 years. Patients with this score are estimated to have a risk of ~50% of having GAS pharyngitis. Although not part of the prediction rule, abdominal pain, nausea, and vomiting are frequently seen in patients with GAS pharyngitis, though only abdominal pain was seen in this patient. What if the patient had presented with low-grade fever (<38°C), cough, sore throat without exudates, conjunctivitis,
