title: Incidence of macrolide-lincosamide-streptogramin B resistance amongst beta-haemolytic streptococci in The Gambia.
abstract: BACKGROUND
  In West Africa, penicillin, macrolide and lincosamide resistance among beta-haemolytic streptococci (BHS) isolates has rarely been described. However, such data are critical to detect and track the emergence of antibiotic resistance.
  
  
  METHODS
  Beta-haemolytic streptococci were cultured from clinical specimens from patients attending the clinic at the Medical Research Council Unit The Gambia (n = 217) and kept at -70 °C. Of these, 186 were revived and tested for penicillin susceptibility by disc diffusion and E-test methods, and the D-test for determination of constitutive and inducible macrolide-lincosamide (MLSB) resistance phenotypes.
  
  
  RESULTS
  The majority of BHS isolates from infections were group A streptococci (GAS) (126/186, 67.7%). Of these, 16% were from invasive disease (30/186). Other BHS isolated included lancefield groups B (19, 10.2%); C (9/186, 4.8%), D (3/186, 1.6%), F (5/186, 2.7%), G (16/186, 8.6%) and non-typeable (8/186, 4.3%). Prevalence of BHS isolated from blood cultures ranges from 0% (2005) to 0.5% (2010). Most (85, 45.7%) of the isolates were from wound infections. Of the 186 BHS isolates, none was resistant to penicillin and 14 (6.1%) were resistant to erythromycin. Of these, 8 (4.3%) demonstrated constitutive MLSBresistance, and 5 (2.7%) were inducible MLSBresistant. All the inducible MLSBisolates were GAS, and majority of the constitutive MLSBisolates (6/8, 75.0%) were non-GAS.
  
  
  CONCLUSIONS
  Beta-haemolytic streptococci, predominantly GAS are associated with a wide range of infections in The Gambia. It is reassuring that macrolide and lincosamide resistance is relatively low. However, monitoring of MLSBresistance is necessary with the global spread of resistant BHS strains.
authors.affiliation: Vaccines and Immunity Theme, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Ebenezer
authors.initials: E
authors.lastname: Foster-Nyarko
authors.affiliation: Vaccines and Immunity Theme, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Brenda
authors.initials: B
authors.lastname: Kwambana
authors.affiliation: Vaccines and Immunity Theme, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Fatima
authors.initials: F
authors.lastname: Ceesay
authors.affiliation: Vaccines and Immunity Theme, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Kaddijatou
authors.initials: K
authors.lastname: Jawneh
authors.affiliation: Clinical Microbiology Department, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Saffiatou
authors.initials: S
authors.lastname: Darboe
authors.affiliation: Vaccines and Immunity Theme, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Sarah N
authors.initials: SN
authors.lastname: Mulwa
authors.affiliation: Clinical Microbiology Department, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Buntung
authors.initials: B
authors.lastname: Ceesay
authors.affiliation: Clinical Microbiology Department, Medical Research Council Unit The Gambia, Banjul, The Gambia.
authors.forename: Ousman O
authors.initials: OO
authors.lastname: Secka
authors.affiliation: Disease Control and Elimination Theme, Medical Research Council Unit The Gambia, Banjul, The Gambia.|Infectious Diseases Epidemiology, London School of Hygiene & Tropical Medicine, London, UK.
authors.forename: Ifedayo
authors.initials: I
authors.lastname: Adetifa
authors.affiliation: Vaccines and Immunity Theme, Medical Research Council Unit The Gambia, Banjul, The Gambia. mantonio@mrc.gm.|Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical Medicine, London, UK. mantonio@mrc.gm.|Microbiology and Infection Unit, Warwick Medical School, University of Warwick, Coventry, UK. mantonio@mrc.gm.
authors.forename: Martin
authors.initials: M
authors.lastname: Antonio
mesh_terms: D000293:Adolescent; D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D005714:Gambia / Q000453:epidemiology; D006461:Hemolysis; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D055231:Lincosamides / Q000494:pharmacology*; D018942:Macrolides / Q000494:pharmacology*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000473:pathology; D013297:Streptococcus pyogenes / Q000187:drug effects* / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity; D025381:Streptogramin B / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D055231:Lincosamides; D018942:Macrolides; D025381:Streptogramin B
keywords: Beta-haemolytic streptococci; Gambia, macrolide–lincosamide resistance