(Modified) Centor criteria for strep throat

Question 1

What are the Centor criteria for strep throat, what’s their use?

Answer 1

Well, Centor criteria a set of criteria used to distinguish strep throat from other pharyngitis.

There are four criterion, and each one gives +1 point:

1. Absence of cough
2. Tonsillar exudates
3. History of Fever
4. Tender anterior cervical lymph nodes

Question 2

There are additional modified Centor criteria, what are they??

Answer 2

Good question, let me tell you: the modified Centor criteria include:

+1 point for age <15
-1 point for age >44

Question 3

Now to the interpretation of the score, what is best advised given points -1 through to +5?

Answer 3

Though this does apperantly also depend on local guildeines, here’s the crux of it:

○ -1 to 1 points (risk is <10%): no swab or ABx necessary.
○ 2 to 3 (15% and 32%) points: use throat culture and ABx if positive.
○ 4 - 5 points: Risk is 56%!! quickly, take a rapid strep test and ABx if positive

Question 4

Something in the notes about the NPV and PPV for Centor criteria, remember what that was?

Answer 4

Indeed I do, for Centor criteria, the NPV with a score of -1 is higher than the PPV
with a score of 5. In other words, the test is better for ruling out strep infections than
confirming them.

Question 5

Okay, now, for strep throat, what are some typical antibiotics, and for whom are they indicated?

Answer 5

Penicillin of course, amoxicillin for children, and IM penicillin benzathine (for the patients likely to be noncompliant)