Fever and sore throat in a child
Answer: You should order a rapid strep test and/or a throat culture.
Strep throat is typically caused by group A beta-hemolytic Streptococcus, also known as Streptococcus pyogenes. This child is a little younger than usual to have strep throat, as the typical age is between 5 and 15 years; however, outliers occur not infrequently. Similar to most respiratory infections, strep throat is more common in children who attend school or pre-school and is also more common during the winter months. The clinical tetrad of strep throat includes fever, tonsillitis with exudate, swollen anterior cervical lymph nodes, and the absence of a cough. The Centor criteria are met if 3 of 4 of these findings are present. These criteria are about 70% sensitive and also 70% specific for the diagnosis of strep throat, which is similar to the performance of rapid strep tests and of throat cultures. Causes of exudative pharyngitis other than group A streptococcus include gonorrhea, group B streptococcus, meningococcus, fusobacteria, and mononucleosis.
A number of less common clinical findings may occur with strep throat and include abdominal pain, headache, palatal petechiae, and the sandpaper rash of scarlet fever. It is useful to know that tonsillar exudate is often absent in younger children, but that in this population atypical features, such as the palatal petechiae seen in this case, are more common. It is also useful to know that the physical examination finding of palatal petechiae is not exclusive to strep throat; other causes include mononucleosis, herpes simplex, adenovirus, and a few others (see Table 1. for other causes of palatal petechiae).
Testing for strep throat is not considered necessary by many experts when 3 of 4 Centor criteria are met. When testing is chosen, it usually starts with a rapid strep test with cultures reserved for cases in which suspicion is high but the rapid test is negative. Unfortunately, culture is not significantly more sensitive than the rapid test but is more costly and time consuming. False positive cultures can occur due to colonization (see Table 1. for test performance characteristics).
Antibiotic treatment of strep throat is usually recommended, though limited data suggest that it significantly decreases the risk of long- or short-term complications such as rheumatic heart disease, glomerulonephritis, peritonsillar abscess, or dehydration-caused difficulty with oral intake. First-line antibiotics include penicillin or amoxicillin, although a single Bicillin injection may also be used and cephalexin may have a lower treatment failure rate. Clindamycin should be reserved for patients with allergies to both penicillins and cephalosporins. Macrolides should usually not be used, as resistance rates are high and they do not cover other bacteria that may mimic strep throat. Prescription analgesics may also be helpful, and a single dose of steroids is often used to decrease inflammation in more severe cases.
Table 1. Strep throat diagnosis and treatment
|Clinical||Typical age: 5 to 15 years, winter|
||Centor criteria: F, exudate, nodes, no cough: 3 of 4: 70%/70%|
||Other symptoms: headache, abdominal pain, rash|
||Peds: Big tonsils, often no exudate in younger kids, palatal petechiae|
|DDx||Gonorrhea, group B strep, meningococcus, fusobacteria, mononucleosis|
||Palate petechiae: strep, mono, CMV, HSV, adenovirus, herpangina, endocarditis, HIV, toxo|
|Tests||Rapid strep: 80% sensitive, 95% specific|
||Throat culture ($300): 80% sensitive, 70% specific|
||If rapid strep negative, consider culture if age 3 to 18 years, unless known exposure|
|Treatment||Bicillin CR, amoxicillin, penicillin, cephalexin, clindamycin|
||No school for 1 to 2 days|
||Avoid macrolides: resistance and do not cover mimics|
||Consider: dexamethasone, opiates|
Brady Pregerson, MD, is an emergency physician at Cedars-Sinai Medical Center in Los Angeles and at Tri-City Medical Center in Oceanside, Calif.
Pregerson B. Quick Essentials: Emergency Medicine: The One-Minute Consult—Version 4.0. ERpocketbooks.com; 2010.