Department of Microbiology and Immunology, Indiana University School of Medicine, Indianapolis, Indiana United States of America.
Department of Medicine, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois United States of America.
PLoS Negl Trop Dis. 2022 Dec 19;16(12):e0011009. doi: 10.1371/journal.pntd.0011009. eCollection 2022 Dec.
In yaws-endemic areas, two-thirds of exudative cutaneous ulcers (CU) are associated with Treponema pallidum subsp. pertenue (TP) and Haemophilus ducreyi (HD); one-third are classified as idiopathic ulcers (IU). A yaws eradication campaign on Lihir Island in Papua New Guinea utilizing mass drug administration (MDA) of azithromycin initially reduced but failed to eradicate yaws; IU rates remained constant throughout the study. Using 16S rRNA gene sequencing, we previously determined that Streptococcus pyogenes was associated with some cases of IU. Here, we applied shotgun metagenomics to the same samples we analyzed previously by 16S rRNA sequencing to verify this result, identify additional IU-associated microorganisms, and determine why S. pyogenes-associated IU might have persisted after MDA of azithromycin.
METHODOLOGY/PRINCIPAL FINDINGS: We sequenced DNA extracted from 244 CU specimens separated into four groups based upon microorganism-specific PCR results (HD+, TP+, TP+HD+, and TP-HD- or IU). S. pyogenes was enriched in IU (24.71% relative abundance [RA]) specimens compared to other ulcer sub-groups, confirming our prior results. We bioinformatically identified the emm (M protein gene) types found in the S. pyogenes IU specimens and found matches to emm156 and emm166. Only ~39% of IU specimens contained detectable S. pyogenes, suggesting that additional organisms could be associated with IU. In the sub-set of S. pyogenes-negative IU specimens, Criibacterium bergeronii, a member of the Peptostreptococcaceae, and Fusobacterium necrophorum (7.07% versus 0.00% RA and 2.18% versus 0.00% RA, respectively), were enriched compared to the S. pyogenes-positive sub-set. Although a broad range of viruses were detected in the CU specimens, none were specifically associated with IU.
CONCLUSIONS/SIGNIFICANCE: Our observations confirm the association of S. pyogenes with IU in yaws-endemic areas, and suggest that additional anaerobic bacteria, but not other microorganisms, may be associated with this syndrome. Our results should aid in the design of diagnostic tests and selective therapies for CU.
在雅司病流行地区，三分之二的渗出性皮肤溃疡（CU）与苍白密螺旋体亚种（TP）和杜克雷嗜血杆菌（HD）有关；三分之一的溃疡被归类为特发性溃疡（IU）。在巴布亚新几内亚的利希尔岛，一项利用阿奇霉素大规模药物管理（MDA）的雅司病根除运动最初减少了雅司病，但未能根除雅司病；IU 率在整个研究过程中保持不变。我们之前使用 16S rRNA 基因测序确定了化脓性链球菌与一些 IU 病例有关。在这里，我们应用 shotgun 宏基因组学对我们之前通过 16S rRNA 测序分析的相同样本进行分析，以验证这一结果，确定与 IU 相关的其他微生物，并确定为什么阿奇霉素 MDA 后与化脓性链球菌相关的 IU 可能持续存在。
方法/主要发现：我们从 244 个 CU 标本中提取 DNA，根据特定于微生物的 PCR 结果将其分为四组（HD+、TP+、TP+HD+和 TP-HD-或 IU）。与其他溃疡亚组相比，化脓性链球菌在 IU（相对丰度[RA]为 24.71%）标本中富集，这证实了我们之前的结果。我们通过生物信息学鉴定了在化脓性链球菌 IU 标本中发现的 emm（M 蛋白基因）类型，并发现与 emm156 和 emm166 匹配。只有约 39%的 IU 标本中含有可检测到的化脓性链球菌，这表明可能还有其他微生物与 IU 相关。在化脓性链球菌阴性 IU 标本的子集中，Criibacterium bergeronii，一种消化链球菌科的成员，和坏死梭杆菌（分别为 7.07%与 0.00% RA 和 2.18%与 0.00% RA），与化脓性链球菌阳性子集相比富集。尽管在 CU 标本中检测到了广泛的病毒，但没有一种病毒与 IU 特异性相关。
结论/意义：我们的观察结果证实了化脓性链球菌与雅司病流行地区 IU 的关联，并表明其他厌氧细菌而不是其他微生物可能与这种综合征相关。我们的结果应该有助于为 CU 设计诊断测试和选择性治疗方法。
