Setor de Patologia Veterinária, Faculty of Veterinary, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil.
Laboratório de Protozoologia e Rickettsioses Vetoriais, Faculty of Veterinary, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, Rio Grande do Sul, Brazil.
Parasitol Res. 2023 Sep;122(9):1973-1982. doi: 10.1007/s00436-023-07895-3. Epub 2023 Jun 22.
Among vector-borne helminths, filarioids of the genus Dipetalonema (Spirurida: Onchocercidae) localize in several tissues and body cavities of several animal species, causing mild to moderate lesions. The pathological findings associated with Dipetalonema spp. infection in Neotropical monkeys from southern Brazil are herein described, along with a fatal case due to filarial polyserositis and entrapment of an intestinal segment. At necropsy, nematodes were observed in abdominal and thoracic cavities, or in the pericardium of 37 (31.3%) out of the 118 individuals examined (i.e., 35 Alouatta guariba clamitans and two Sapajus nigritus). In addition, at histology, 27.0% of positive animals presented microfilarie (inside blood vessels of lung, spleen, liver, and brain) and 8.1% presented adult nematodes in the heart, lung, and liver. In two cases, cross-sections of filarioids were associated with areas of epicardial thickening with intense fibrosis and pyogranulomatous inflammation in the brain, heart, liver, lungs, or spleen. The DNA fragment was amplify using the cox1 gene, sequenced and analyzed to identify the nematode species collected; presence of Wolbachia was assessed in the filarioids using the 16S rRNA gene. At BLAST analysis of the cox1 gene, 10 sequences showed 91.7% nucleotide identity with Dipetalonema gracile, and two with D. gracile (98.5%) and Dipetalonema graciliformis (98.3%). Phylogenetic analyses clustered sequences of the cox1 obtained in this study in two clades corresponding with the host species. Wolbachia sp. endosymbiont was detected in four samples. Data herein reported provide a description of pathological lesions associated with the infection by Dipetalonema spp., suggesting that they may cause disease in Neotropical monkeys. In addition, a better understanding of diversity and biology of Dipetalonema spp. in South America is needed to assess the impact they may cause in native non-human primates from Brazil.
在虫媒蠕虫中，双鳞属的线虫（旋尾目：盘尾丝虫科）定位于几个动物物种的几种组织和体腔中，引起轻度至中度病变。本文描述了来自巴西南部新热带地区的猴子中与双鳞属线虫感染相关的病理发现，以及一例因丝状多浆膜炎和肠段嵌塞导致的致命病例。在剖检时，在 118 只被检查的个体（即 35 只白掌长臂猿和 2 只黑掌蜘蛛猴）的腹部和胸部或心包中观察到线虫。此外，在组织学上，27.0%的阳性动物有微丝蚴（在肺、脾、肝和脑的血管内），8.1%的阳性动物有心、肺和肝中的成虫线虫。在两个病例中，线虫的横切面与心外膜增厚、脑、心、肝、肺或脾的强烈纤维化和化脓性炎症区域有关。使用 cox1 基因扩增 DNA 片段，测序并分析以鉴定收集的线虫种类；使用 16S rRNA 基因评估线虫中的沃尔巴克氏体。cox1 基因的 BLAST 分析显示，10 个序列的核苷酸同一性为 91.7%，与双鳞线虫相似，2 个序列与双鳞线虫（98.5%）和双鳞线虫（98.3%）相似。cox1 获得的序列的系统发育分析将本研究中的序列聚类为两个分支，对应于宿主物种。在四个样本中检测到沃尔巴克氏体属内共生体。本文报道的数据提供了与双鳞属线虫感染相关的病理损伤描述，表明它们可能导致新热带猴子患病。此外，需要更好地了解南美的双鳞属线虫的多样性和生物学，以评估它们对巴西本土非人类灵长类动物可能造成的影响。
