Streptococcus Diagnosis

[Cofftarkin]

A 28-year old woman who presented with a history of joint pain and swelling, initially in her right foot and ankle that resolved after a few days and then pain and swelling in other joints. Upon physical examination, diffuse tenderness of the joints was noted on palpation but no swelling or erythema. Cardiovascular examination was notable for tachycardia, but no murmurs were detected. The diagnosis of a “viral infection” was made and she was discharged with a course of nonsteroidal antiinflammatory drugs. After 5 days, the patient returned with progressive shortness of breath and persistent pain in her knee.

Physical examination revealed a low-grade temperature, tachycardia, and a new heart murmur with mitral valve regurgitation. The left knee was warm to the touch, the range of motion was limited, and it was painful on flexion. The diagnosis of bacterial endocarditis was considered but all blood cultures were negative.

Medical history revealed that as a child she became short of breath easily and was unable to play with other children. The patient’s history of dyspnea is consistent with rheumatic heart disease, as is the combination of fever, mitral regurgitation, and migratory arthritis. Recent evidence of infection with group A Streptococcus is required to confirm the diagnosis.

What infection do you think the 28 y/o patient portray?

What can you suggest to verify the A Streptococcus diagnosis