风湿性心脏病二级预防患儿中β溶血性链球菌的咽拭子培养阳性率及抗生素敏感性模式

Throat culture positivity rate and antibiotic susceptibility pattern of beta-hemolytic streptococci in children on secondary prophylaxis for rheumatic heart disease.

作者信息

Zegeye Nigus, Asrat Daniel, Woldeamanuel Yimtubezinash, Habte Abebe, Gedlu Etsegenet, Tønjum Tone, Aseffa Abraham

机构信息

Department of Medicine, DebreBerhan University, P. O. Box: 445, DebreBerhan, Ethiopia.

Armauer Hansen Research Institute, Jimma Road, PO Box 1005, Addis Ababa, Ethiopia.

出版信息

BMC Infect Dis. 2016 Sep 23;16(1):510. doi: 10.1186/s12879-016-1841-3.

DOI:10.1186/s12879-016-1841-3

PMID:27663649

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC5035452/

Abstract

BACKGROUND

Among children diagnosed to have chronic rheumatic valvular heart disease (RHD) in Ethiopia, many have been observed to develop recurrence of rheumatic fever (RF) despite secondary prophylaxis. This study determined the throat culture positivity rate and drug susceptibility pattern of beta hemolytic streptococci (BHS) isolated from children attending a specialized cardiac clinic in Ethiopia.

METHODS

Throat swabs were collected from 233 children receiving benzathine penicillin injection as secondary prophylaxis for RHD and cultured. The bacterial isolates were characterized using Matrix Assisted Laser Desorption/Ionization-Time of Flight (MALDI-TOF) mass spectrometry. Drug susceptibility was tested with the Kirby Bauer disc diffusion method. Anti-streptolysin O (ASO) titers were determined using ASO latex reagents.

RESULTS

The throat culture positivity rate for BHS was 24 % (56/233). Among the BHS bacterial strains isolated, four were characterized as S. pyogenes and another four as S. dysgalactiae subsp. equisimilis (Lancefield group A, C and G). All BHS were susceptible to penicillin except one isolate of S. agalactiae. Among 233 children enrolled, 46(19.7 %) showed increased ASO titer. Children who received antibiotic prophylaxis within 2-weeks of last injection had significantly lower BHS throat culture positivity rate than those injected every 4-weeks (p = 0.02). Children who missed at least one prophylaxis within the last 6 months had a higher BHS culture positivity rate than those who did not miss any (p = 0.0003).

CONCLUSIONS

The presence of groups A, C and G streptococci in the throat of children under secondary prophylaxis for RHD and increased ASO titer suggests failure of the regimen. This calls for further investigation into the causes of inadequate prophylaxis (including bioavailability of drugs used, optimal duration and patient compliance) and intervention.

摘要

背景

在埃塞俄比亚被诊断患有慢性风湿性心脏瓣膜病（RHD）的儿童中，尽管进行了二级预防，但仍有许多儿童出现风湿热（RF）复发。本研究确定了从埃塞俄比亚一家专门的心脏诊所就诊的儿童中分离出的β溶血性链球菌（BHS）的咽培养阳性率和药敏模式。

方法

从233名接受苄星青霉素注射作为RHD二级预防的儿童中采集咽拭子并进行培养。使用基质辅助激光解吸/电离飞行时间（MALDI-TOF）质谱对细菌分离株进行鉴定。采用 Kirby Bauer 纸片扩散法检测药敏情况。使用抗链球菌溶血素O（ASO）乳胶试剂测定ASO滴度。

结果

BHS的咽培养阳性率为24%（56/233）。在分离出的BHS菌株中，4株被鉴定为化脓性链球菌，另外4株为马链球菌兽疫亚种（兰斯菲尔德A、C和G组）。除1株无乳链球菌分离株外，所有BHS对青霉素均敏感。在纳入的233名儿童中，46名（19.7%）ASO滴度升高。在最后一次注射后2周内接受抗生素预防的儿童，其BHS咽培养阳性率显著低于每4周注射一次的儿童（p = 0.02）。在过去6个月内至少漏服一次预防药物的儿童，其BHS培养阳性率高于未漏服任何药物的儿童（p = 0.0003）。