Purpose

Blastocystis spp. are parasites of the intestinal tract found in many hosts including humans. This pathogen is commonly found in immunocompetent in asymptomatic individuals and in patients with gastrointestinal and extra-intestinal symptoms. Recently, it has been implicated as an important cause of diarrheal illness in immunocompromised individuals, including HIV-infected patients. At least six life cycle stages have been described in faeces and cultures, namely vacuolar, granular, multi-vacuolar, avacuolar, ameboid and cyst forms. The aim of the present study was to describe the histological findings of Blastocystis infection in an adult HIV-infected patient with gastrointestinal symptoms.

Methods

Parasitological techniques and PCR were applied to stool samples. Histological analysis was performed on duodenal biopsy specimens.

Results

Standard parasitological methods revealed vacuolar, granular, cyst and multi-vacuolar forms of Blastocystis in faecal samples with the presence of Blastocystis DNA being confirmed by PCR. DNA sequencing revealed Blastocystis subtype ST1. Histological findings in duodenal samples showed an inflammatory infiltrate with plasma cells and lymphocytes. We identified cyst, granular, ameboid and multi-vacuolar forms in the lumen.

Conclusion

To our knowledge, there are no previous peer review reports describing these four different forms of Blastocystis in histological sections from the lumen and the brush border of the enterocytes.

中文翻译：

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HIV感染患者小肠中囊胚生命周期形式的诊断特征

目的

芽生菌属 是在包括人类在内的许多宿主中发现的肠道寄生虫。这种病原体常见于免疫功能正常的无症状个体以及有胃肠道和肠外症状的患者中。最近，它被认为是免疫功能低下的个体（包括 HIV 感染者）腹泻的重要原因。在粪便和培养物中至少描述了六个生命周期阶段，即液泡、颗粒、多液泡、液泡、变形虫和囊肿形式。本研究的目的是描述在一名患有胃肠道症状的成年 HIV 感染患者中囊胚感染的组织学发现。

方法

将寄生虫学技术和 PCR 应用于粪便样本。对十二指肠活检标本进行组织学分析。

结果

标准的寄生虫学方法揭示了粪便样本中的空泡、颗粒、囊肿和多空泡形式的囊胚，通过 PCR 证实了囊胚DNA 的存在。DNA 测序显示芽生菌亚型 ST1。十二指肠样本的组织学发现显示浆细胞和淋巴细胞的炎症浸润。我们在管腔中发现了囊肿、颗粒、变形虫和多空泡形式。

结论

据我们所知，以前没有同行评审报告在肠腔和肠细胞刷状缘的组织切片中描述这四种不同形式的囊胚。