2021年6—9月收集天门市第一人民医院长期住院患者基本信息（性别、年龄、粪便性状、隐血试验结果、临床症状体征等），采集患者粪样，以生理盐水直接涂片法置显微镜下检查，对疑似人芽囊原虫阳性粪样提取DNA，使用人芽囊原虫特异引物BhRDr和RD5扩增目的条带，阳性粪样送至北京诺赛基因组研究中心有限公司进行测序。患者粪样同时观察蓝氏贾第鞭毛虫和脆弱双核阿米巴感染情况。采集患者抗凝全血和非抗凝静脉血进行血液分析。857例患者中共检出人芽囊原虫阳性粪样42例，阳性检出率为4.90％，其中男性4.27%（19/445），女性5.58%（23/412），性别间阳性率差异无统计学意义（χ² = 0.791，P > 0.05）。不同年龄组中，≥ 61岁组阳性率最高（6.38%，22/345）；不同年龄间阳性检出率差异无统计学意义（χ² = 2.700，P > 0.05）。不同的粪样性状中，以稀便检出阳性率最高（18.37%，27/147）（χ² = 98.930，P < 0.05）。隐血试验便血者检出率为6.72%（9/134），未便血者为4.56%（33/723），阳性检出率差异无统计学意义（χ² = 1.123，P > 0.05）。不同临床症状中以“腹痛且腹泻”阳性率最高（4/11）（χ² = 53.956，P < 0.05）。患者中检出人芽囊原虫混合蓝氏贾第鞭毛虫感染者6例，混合脆弱双核阿米巴原虫感染者2例。人芽囊原虫感染者红细胞计数为（3.97 ± 7.39） × 10¹²/L，血红蛋白为（119.02 ± 21.49） g/L，均低于非感染者[（4.27 ± 0.44） × 10¹²/L，（126.52 ± 14.30）g/L ]（t = 2.556、 2.235，均P < 0.05）。人芽囊原虫基因测序结果共有4种基因型（ST1、ST3、ST6、ST7），以ST3为主，占57.1％（24/42）。

Basic information (gender, age, fecal characteristics, occult-blood test results, clinical signs and symptoms, etc) of long-term hospitalized patients in Tianmen First People’s Hospital during June—September 2021 collected. The fecal samples of patients were collected and examined under microscope by direct smear with normal saline. The DNA were extracted from the suspected Blastocystis hominis positive fecal samples. Specific primers of B. hominis BhRDr and RD5 were used to amplify the target bands, and the positive fecal samples were sent to Norsay Genomics Research Center for sequencing. Giardia lamblia and fragile bicarbonate amoeba infection were also observed in the fecal samples of the patients. Anticoagulant whole blood and non-anticoagulant venous blood were collected for blood analysis. Among the 857 patients, 42 cases were positive for B. hominis, with a positive rate of 4.90%. The positive rate of males was 4.27% (19/445) and that among the females was 5.58% (23/412). There was no significant difference between the gender groups (χ² = 0.791, P < 0.05). In different age groups, the positive rate was the highest in the ≥ 61 years old group (6.38%, 22/345). There was no significant difference in positive rates among different age groups (χ² = 2.700, P > 0.05). Among different fecal characters, the positive rate of the loose stool samples was the highest (18.37%, 27/147) (χ² = 98.930, P < 0.05). The positive rate was 6.72% (9/134) in patients with hematochezia and 4.56% (33/723) in patients without hematochezia, with no significant difference (χ² = 1.123, P > 0.05). Among different clinical symptoms, patients with abdominal pain and diarrhea had the highest positive rate (4/11) (χ² = 53.956, P < 0.05). Six patients were infected with B. hominis mixed with G. Lamblia, and two were infected with amoeba fragile. The red blood cell count and hemoglobin of B. hominis infected patients were (3.97 ± 7.39) × 10¹²/L and (119.02 ± 21.49) g/L, both of which were lower than that of the non-infected patients [(4.27 ± 0.44) × 10¹²/L, (126.52 ± 14.30) g/L] (t = 2.556, 2.235; P < 0.05). There were four genotypes of B. hominis (ST1, ST3, ST6 and ST7), and ST3 was the dominant one, accounting for 57.1% (24/42).