Prevalence of Entamoeba histolytica and other enteral parasitic diseases in the metropolitan region of Belo Horizonte, Brazil. A cross-sectional study

ABSTRACT BACKGROUND: Enteral parasitic diseases are a public health problem in nations with low economic development and in settings with poor sanitation. Amebiasis is the second most frequent form of parasitosis, with a high burden of disease. Knowledge of the prevalence of enteroparasitoses in a given region is useful for planning clinical decision-making. Thus, the aim of this study was to estimate the prevalence of enteral parasitic diseases, especially amebiasis, through analysis on stool samples from public and private laboratories in a metropolitan area in southeastern Brazil. DESIGN AND SETTING: Cross-sectional study conducted in the metropolitan region of Belo Horizonte, Brazil. METHODS: We evaluated 6,289 fecal samples from one private and one public laboratory. The samples were concentrated by means of spontaneous sedimentation, and those that were positive for Entamoeba histolytica or Entamoeba dispar in optical microscopy analyses were processed to obtain deoxyribonucleic acid, with subsequent identification through the polymerase chain reaction. RESULTS: Among the stool samples, 942 (15.0%) had parasitic infections; 73 (1.2%) of these were helminthic infections and 847 (13.5%) were protozoan infections, caused mainly by Escherichia coli (6.0%), Endolimax nana (5.2%) and Giardia lamblia (1.2%). Infections due to Entamoeba histolytica or Entamoeba dispar occurred in 36 samples (0.6%) and the polymerase chain reaction revealed five (13.9%) as Entamoeba histolytica. CONCLUSION: The prevalence of enteral parasitic diseases is high in the metropolitan region of Belo Horizonte, although amebiasis may not be a problem.

ABSTRACT 背景：肠道寄生虫病是经济欠发达经济体及卫生条件恶劣地区的公共卫生问题。阿米巴病是第二常见的寄生虫病类型，疾病负担沉重。掌握特定地区肠道寄生虫病的患病率，对规划临床决策具有指导意义。因此，本研究旨在通过分析巴西东南部大都会地区公立与私立实验室的粪便样本，估算肠道寄生虫病（尤其是阿米巴病）的患病率。
研究设计与场景：本研究为横断面研究，在巴西贝洛奥里藏特大都会地区开展。
方法：本研究评估了来自1家私立实验室与1家公立实验室的6289份粪便样本。采用自然沉淀法对样本进行浓缩，对于光学显微镜检测呈溶组织内阿米巴（Entamoeba histolytica）或迪斯帕内阿米巴（Entamoeba dispar）阳性的样本，提取脱氧核糖核酸（deoxyribonucleic acid, DNA），随后通过聚合酶链式反应（polymerase chain reaction, PCR）完成鉴定。
结果：在全部粪便样本中，942份（15.0%）检出寄生虫感染；其中73份（1.2%）为蠕虫感染，847份（13.5%）为原虫感染，主要致病病原体为大肠埃希菌（6.0%）、微小内蜒阿米巴（5.2%）与蓝氏贾第鞭毛虫（1.2%）。36份样本（0.6%）检出溶组织内阿米巴或迪斯帕内阿米巴感染，经聚合酶链式反应鉴定后，其中5份（13.9%）为溶组织内阿米巴感染。
结论：贝洛奥里藏特大都会地区的肠道寄生虫病患病率较高，但阿米巴病或并非当地突出的公共卫生问题。