infectious diseases
Streptococcal Infections
Key Points
The most significant streptococcal pathogen isS. pyogenes, which is denoted as group A beta-hemolytic streptococci (GABHS). The 2 most common acute diseases due to GABHS are pharyngitis and skin infections. Delayed nonsuppurative complications, including rheumatic fever and poststreptococcal glomerulonephritis, can occur. Rapid antigen tests (ie, for point-of-care use) are very specific but not highly sensitive; confirm negative results using culture, at least in children. A penicillin or cephalosporin is preferred for pharyngitis; because macrolide resistance is increasing, susceptibility testing is recommended if that class of antibiotic is used. For skin infection, givedicloxacillinorcephalexinif MRSA is not likely, but give TMP/SMX,linezolid,minocycline, orclindamycinif MRSA is suspected. Treat groups B, C, and G streptococcal infections with the same antibiotics used for treating GABHS. 