RESUMO
Staphylococcus aureus from sub-Saharan Africa is frequently resistant to antimicrobial agents that are commonly used to treat invasive infections in resource-limited settings. The underlying mechanisms of resistance are largely unknown. We therefore performed whole genome sequencing (WGS) on S. aureus from the Democratic Republic of the Congo (DRC) to analyse the genetic determinants of antimicrobial resistance. One hundred S. aureus samples were collected from community-associated asymptomatic nasal carriers in the metropolitan area of Kinshasa, DRC, between 2013 and 2014. Phenotypic resistance against 15 antimicrobial agents was compared to the genotypic results that were extracted from WGS data using Mykrobe predictor and the SeqSphere(+) software that screened for 106 target genes associated with resistance. Isolates were phenotypically resistant against penicillin (97%, n=97), trimethoprim (72%, n=72) and tetracycline (54%, n=45). Thirty-three isolates (33%) were methicillin-resistant S. aureus (MRSA). Of these, nine isolates (27.3%) were oxacillin-susceptible MRSA (OS-MRSA) and belonged to ST8 (t1476). The Y195F mutation of FemA was associated with OS-MRSA (p 0.015). The majority of trimethoprim resistant isolates carried dfrG. Tetracycline resistance was associated with tet(K). The concordance between phenotypic susceptibility testing and both WGS analysis tools was similar and ranged between 96% and 100%. In conclusion, a high proportion of OS-MRSA in the DRC was linked to mutations of FemA. Genotypic and phenotypical antimicrobial susceptibility testing showed high concordance. This encourages the future use of WGS in routine antimicrobial susceptibility testing.
Assuntos
DNA Bacteriano/química , DNA Bacteriano/genética , Farmacorresistência Bacteriana , Análise de Sequência de DNA , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/genética , Adolescente , Adulto , Antibacterianos/farmacologia , Portador Sadio/microbiologia , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , República Democrática do Congo , Feminino , Genoma Bacteriano , Humanos , Masculino , Testes de Sensibilidade Microbiana , Mucosa Nasal/microbiologia , Staphylococcus aureus/isolamento & purificação , Adulto JovemRESUMO
La transmission verticale du VIH est la cause principale de l'infection pediatrique par le VIH. Plusieurs schemas d'antiretroviraux (ARV) sont utilises dans les programmes de Prevention de la Transmission de la Mere a l'Enfant (PTME) ; allant de la dose unique prophylactique a base de la Nevirapine (NVP); a l'utilisation des Antiretroviraux a Haute Activite Therapeutique (HAART). Dans cette etude nous cherchons a determiner la prevalence de la transmission perinatale du VIH sous monotherapie a la Nevirapine utilisee dans la PTME en Republique Democratique du Congo (RDC). La charge virale a ete dosee par PCR-RNA chez 147 meres seropositives consentantes ainsi que chez leurs enfants. Un premier prelevement de sang veineux a ete effectue a l'entree en salle de travail; un deuxieme a l'accouchement; chez les meres. Concernant les enfants; un prelevement a ete effectue au cordon ombilical et un autre entre 6 et 10 semaines de vie ex utero. De 146 echantillons de sang du cordon; 21 n'ont pas ete analyses; car alteres. Les particules virales ont ete retrouvees dans 19/125 echantillons preleves a la naissance; soit 15;20. Lors du 2ieme prelevement; cette charge virale est devenue indetectable chez 17/19. Seuls 80 enfants ont ete retrouves pour ce deuxieme prelevement. En definitif 67 enfants ont eu des analyses effectuees successivement sur les prelevements du cordon et sur ceux pratiques entre 6 et 10 semaines apres la naissance et 11 etaient infectes; soit 16;40(IC a 95: 8;50-27;50).Ces donnees sont les premieres rapportees en RDC