de Almeida Torres Rosângela Stadnick Lauth, dos Santos Talita Zajac, Torres Robson Antônio de Almeida, Petrini Lygia Maria Coimbra de Manuel, Burger Marion, Steer Andrew C, Smeesters Pierre R
Laboratório de Bacteriologia, Divisão de Laboratórios de Epidemiologia e Controle de Doenças, Laboratório Central do Estado do Paraná Universidade Positivo, Curitiba.
Pontifícia Universidade Católica do Paraná
J Pediatric Infect Dis Soc. 2016 Mar;5(1):47-52. doi: 10.1093/jpids/piu107. Epub 2014 Oct 30.
Conflicting recommendations regarding antibiotic prophylaxis for contacts of patients with invasive group A streptococcal (GAS) infection exist. Close contacts of patients with such severe and rapidly progressive disease often strongly appeal to the treating clinicians for antimicrobial treatment to prevent additional cases. We aimed to use an approach based on pharyngeal culture testing of contacts and targeted antibiotic prophylaxis.
A large throat swab survey including 105 contacts was undertaken after a fulminant and fatal case of GAS necrotizing fasciitis. GAS strains were characterized by emm typing and antimicrobial susceptibility to 7 antibiotics. The presence of 30 virulence determinants was determined by polymerase chain reaction and sequencing.
The GAS isolate recovered from the index patient was an M1T1 GAS clone susceptible to all antimicrobial agents tested. The same clone was present in the throat of 36% of close contacts who had exposure to the index patient (family households and classroom contacts) for >24 hours/week, whereas the strain was present in only 2% of the other contacts.
Although the study does not allow firm conclusions to be drawn as to whether antibiotic prophylaxis is effective, we describe a practical approach, including an educational campaign and targeted antibiotic treatment to close contacts who have been exposed to an index patient for > 24 hours/week before the initial disease onset.
对于侵袭性A组链球菌（GAS）感染患者的接触者，关于抗生素预防的建议存在冲突。患有这种严重且进展迅速疾病的患者的密切接触者常常强烈要求治疗临床医生进行抗菌治疗以预防更多病例。我们旨在采用一种基于对接触者进行咽培养检测和针对性抗生素预防的方法。
在一例暴发性致死性GAS坏死性筋膜炎病例后，对105名接触者进行了大规模咽拭子调查。通过emm分型和对7种抗生素的药敏试验对GAS菌株进行了鉴定。通过聚合酶链反应和测序确定了30种毒力决定因素的存在情况。
从索引患者分离出的GAS菌株是一株M1T1 GAS克隆，对所有测试抗菌药物敏感。在每周与索引患者（家庭住户和班级接触者）接触超过24小时的密切接触者中，36%的人咽喉中存在相同克隆，而在其他接触者中该菌株仅存在于2%的人咽喉中。
尽管该研究无法就抗生素预防是否有效得出确凿结论，但我们描述了一种实用方法，包括开展教育活动以及对在初始疾病发作前每周与索引患者接触超过24小时的密切接触者进行针对性抗生素治疗。
