The most useful test for evaluation of suspected acute rheumatic fever is:

The most useful test for evaluation of suspected acute rheumatic fever is:

• A. Urinalysis
• B. Antistreptolysin-O titer
• C. Electrocardiogram
• D. Hemoglobin electrophoresis

Answer: (B)

Acute rheumatic fever is a delayed inflammatory reaction that follows a group A streptococcal throat infection, so proving there was a recent GAS infection is essential to establish the diagnosis alongside the clinical features. Antistreptolysin-O antibodies rise after GAS infection and serve as a marker of recent exposure. This serologic test helps link the preceding strep infection to the current presentation, especially since throat cultures or rapid tests may be negative by the time rheumatic fever develops. Therefore, it is the most useful test for evaluating suspected ARF. Urinalysis isn’t diagnostic for ARF and may be used for other considerations, but it doesn’t confirm prior infection. An electrocardiogram can detect cardiac involvement from rheumatic carditis but doesn’t establish that a streptococcal infection preceded the illness. Hemoglobin electrophoresis is unrelated to diagnosing ARF and is used for evaluating hemoglobinopathies.

Acute rheumatic fever is a delayed inflammatory reaction that follows a group A streptococcal throat infection, so proving there was a recent GAS infection is essential to establish the diagnosis alongside the clinical features. Antistreptolysin-O antibodies rise after GAS infection and serve as a marker of recent exposure. This serologic test helps link the preceding strep infection to the current presentation, especially since throat cultures or rapid tests may be negative by the time rheumatic fever develops. Therefore, it is the most useful test for evaluating suspected ARF.

Urinalysis isn’t diagnostic for ARF and may be used for other considerations, but it doesn’t confirm prior infection. An electrocardiogram can detect cardiac involvement from rheumatic carditis but doesn’t establish that a streptococcal infection preceded the illness. Hemoglobin electrophoresis is unrelated to diagnosing ARF and is used for evaluating hemoglobinopathies.