mefA gene encoding a macrolide efflux pump, conferring an M phenotype (macrolide resistance alone)
ermA gene encoding inducible methylation of 23S ribosome, conferring an MLSB phenotype (macrolide-lincosamide-streptogramin B resistance), which is detectable using a D test
Laboratory confirmation of infection with or without clinical evidence of invasive disease, requiring isolation of group A streptococcus (Streptococcus pyogenes) from a normally sterile site
Blood, CSF, pleural fluid, pericardial fluid, peritoneal fluid, deep tissue specimen taken during surgery (e.g. muscle collected during debridement for necrotizing fasciitis), bone or joint fluid excluding the middle ear and superficial wound aspirates (e.g. skin and soft tissue abscesses).
Probable Case
Clinical evidence of invasive disease in the absence of another identified aetiology and with non-confirmatory laboratory evidence of infection:
Isolation of group A streptococcus from a non-sterile site, or
Positive group A streptococcus antigen detection
Clinical Evidence
Streptococcal toxic shock syndrome, which is characterized by hypotension (systolic blood pressure ≤ 90 mm Hg in an adult and < 5 percentile for age for children) and at least two of the following signs:
Renal impairment (creatinine level ≥ 177 μmol/L for adults)
Coagulopathy (platelet count ≤ 100,000/mm3 or disseminated intravascular coagulation)
Liver function abnormality (SGOT, SGPT, or total bilirubin ≥ 2x upper limit of normal)
Adult respiratory distress syndrome
Generalized erythematous macular rash that may desquamate
Soft-tissue necrosis, including necrotizing fasciitis, myositis or gangrene
Household contacts who have spent at least 4 hours/day on average in the previous 7 days or 20 hours/week
Non-household persons who share the same bed with the case or had sexual relations with the case
Persons who have had direct mucous membrane contact with the oral or nasal secretions of a case (e.g. mouth-to-mouth resuscitation, open mouth kissing) or unprotected direct contact with an open skin lesion of the case
Injection drug users who have shared needles with the case
Selected LTCF contacts
Selected child care contacts
Selected hospital contacts
First-line: cephalexin 25 to 50 mg/kg (max 1 g) daily split bid to qid for 10 days
Second-line depends on local antimicrobial resistance patterns:
Erythromycin 5 to 7.5 mg/kg po q6h (or 10 to 15 mg/kg po q12h) in children, or 500 mg po q12h in adults, for 10 days
Clarithromycin 7.5 mg/kg (max 250 mg) po q12h in children, or 250 mg po bid in adults, for 10 days
Clindamycin 8 to 16 mg/kg po daily split tid or qid in children, or 150 mg po qid in adults, for 10 days
^Athanasios G. Michos, Chrysanthi G. Bakoula, Maria Braoudaki, Foteini I. Koutouzi, Eleftheria S. Roma, Anastasia Pangalis, Georgia Nikolopoulou, Elena Kirikou, Vassiliki P. Syriopoulou. Macrolide resistance in Streptococcus pyogenes: prevalence, resistance determinants, and emm types. Diagnostic Microbiology and Infectious Disease. 2009;64(3):295-299. doi:10.1016/j.diagmicrobio.2009.03.004.
^Walter H. Traub, Birgit Leonhard. Comparative Susceptibility of Clinical Group A, B, C, F, and G β-Hemolytic Streptococcal Isolates to 24 Antimicrobial Drugs. Chemotherapy. 1997;43(1):10-20. doi:10.1159/000239529.
abMatthias Imöhl, Mark van der Linden. Jose Melo-Cristino. Antimicrobial Susceptibility of Invasive Streptococcus pyogenes Isolates in Germany during 2003-2013. PLOS ONE. 2015;10(9):e0137313. doi:10.1371/journal.pone.0137313.
^A. C. Bowen, R. A. Lilliebridge, S. Y. C. Tong, R. W. Baird, P. Ward, M. I. McDonald, B. J. Currie, J. R. Carapetis. Is Streptococcus pyogenes Resistant or Susceptible to Trimethoprim-Sulfamethoxazole?. Journal of Clinical Microbiology. 2012;50(12):4067-4072. doi:10.1128/jcm.02195-12.
