赣州市人芽囊原虫感染的流行病学调查分析

目的了解赣州市人芽囊原虫病流行情况。方法随机抽取江西省赣州市5个县（市）20个调查点,调查不同人群、6种家禽家畜人芽囊原虫感染率,粪检采用生理盐水涂片法。采集生活污水饮用水及自然水源水样,用自然沉淀法查人芽囊原虫污染程度。结果共检查不同人群1 336人,查出人芽囊原虫感染99人,感染率为7.41%。采集5种家禽家畜粪便628份,查出人芽囊原虫67份,平均感染率为10.67%。调查3种水体标本304份,阳性11份,占3.62%。结论赣州市人群与6种家禽家畜均存在人芽囊原虫感染,3种水体均受到人芽囊原虫污染。     

一起人芽囊原虫病暴发流行的调查研究

江西省崇义县横水镇在１９９６年１０月２５日至１１月１日发生了１１２２例芽囊原虫病,人群总发病率为２．３９％。为查明本次暴发流行的原因,１９９７我们采用疫情资料回顾性调查和病原体实验研究的方法,证实本次暴发流行是通过污染的水而传播,同时与带虫者粪便中病原体的耐低渗性和居民饮用水的不良卫生习惯有关。     

湘西自治州不同人群人芽囊原虫感染情况调查

目的 了解湘西自治州农村人群和腹痛、腹泻患者人芽囊原虫的感染情况.方法 对湘西凤凰县农村人群和在湘西自治州疾控中心寄生虫病室就诊的腹痛、腹泻患者收集便样,采用碘液涂片检查人芽囊原虫.结果 共检查1783人,人芽囊原虫阳性328人,阳性率为18.45％.其中农村人群粪检11个村1 439人,人芽囊原虫阳性226人,阳性率为15.71％;门诊腹痛、腹泻患者粪检344人,人芽囊原虫阳性102人,阳性率为29.65％,2者差异有统计学意义(x2=35.97,P＜0.05);男女间感染率差异无统计学意义(x2=0.001,P＞0.05);农村人群以青壮年为高,感染率为22.16％,而门诊患者以＞5～ 10岁儿童为高,感染率为43.00％;土家族、苗族感染率分别20.67％、19.11％,2者无统计学意义,而汉族低于前2者为13.79％,差异有统计学意义(x2=8.91 P＜0.05);在学龄前儿童、学生、职员、农民人群中,以农民为高,感染率为21.19％;城、乡人群感染率分别为15.71％和19.35％,差异无统计学意义(x2=3.07,P＞0.05).湘西自治州农村人群感染率最低的村为7.35％,最高的村为33.33％.结论 湘西自治州人群人芽囊原虫感染率较高,人芽囊原虫是腹痛、腹泻患者的主要病因之一.     

上海市不同人群人芽囊原虫感染调查

目的了解上海市不同人群人芽囊原虫感染情况。方法在上海市6个区收集居民新鲜粪便,采用Ringer溶液37℃恒温条件下培养人芽囊原虫,计算人芽囊原虫感染率。结果检查居民2 984人,人芽囊原虫阳性者88人,感染率2.95%。上海市各区人群感染率间差异无统计学意义(χ~2=9.90,P>0.05);青浦区男性感染率为5.56%,女性感染率1.57%,差异有统计学意义(χ~2=5.38,P<0.05),其他5个区男、女性感染率差异无统计学意义(χ~2=0.08～0.54,P均>0.05);农民感染率为6.87%,与其他职业人群比较差异有统计学意义(χ~2=18.57,P<0.05)。结论上海市人群对人芽囊原虫普遍易感,以农民感染率最高。体外培养法敏感性较高.可用于人芽囊原虫感染的流行病学调查。     

一起人芽囊原虫病暴发流行的调查研究

江西省崇义县横水镇在 1996年 10月 2 5日至 11月 1日发生了 112 2例人芽囊原虫病 ,人群总发病率为2 .39%。为查明本次暴发流行的原因 ,1997年我们采用疫情资料回顾性调查和病原体实验研究的方法 ,证实本次暴发流行是通过污染的水而传播 ,同时与带虫者粪便中病原体的耐低渗性和居民饮用水的不良卫生习惯有关。     

人芽囊原虫感染小鼠试验

目的 通过感染不同免疫状态ICR小鼠寻求人芽囊原虫(Blastocystis hominis, B.h)对小鼠的易感途径及有效感染数量。 方法 ①将104、105、106个培养３代的B.h分别经口及直肠感染ICR小鼠。② 106个B.h经直肠感染免疫功能低下该种小鼠，观察感染后不同时间小鼠胃肠道B.h繁殖情况及消化道组织病理改变。 结果 B.h经口及直肠两种途径均可使小鼠感染，免疫功能低下小鼠感染后出现行动迟缓、精神萎靡、嗜睡、体重下降等，部分小鼠出现腹泻，排粘液便等症状，个别小鼠死亡。经解剖肉眼观察见空回肠、回盲部、结肠的肠壁组织严重水肿、充血、淤血等。在小鼠胃肠道内容物中均发现B.h。病理切片显示，小肠及结肠黏膜上皮脱落，黏膜下层不同程度的炎性细胞浸润，腺体结构不完整。 结论 B.h经直肠比经口更易感染小鼠，B.h可寄生于小鼠整个胃肠道。小鼠免疫功能降低时，B.h可迅速繁殖、致病性增强，并引起严重的肠黏膜病理改变。     

婴儿感染人芽囊原虫1例报告

患儿,女性,4月龄,湖南省常德市临澧城关镇人。因无明显诱因血样便,于2006年5月8日来广西医科大学一附院儿科就诊。大便3次/d,有腥臭味,较稀烂,伴少许黏液,无浓性物,量中等,同时伴呕吐(非喷射状),无咖啡样物,进食即吐,无明显烦躁和哭闹。患儿为顺产第1胎,新法接生,出生时体重3.1     

人芽囊原虫的研究进展

人芽囊原虫是一种常见的人和哺乳动物道寄生性原虫。该生物体过去长期被错误地归属于酵母菌,直到1976年才逐渐确立其原虫地位。本从生物学（分类学、形态学、生活史、体外培养、动物病理）、流行病学、免疫学、临床表现、治疗及实验室检查等几个不同的方面简要地概述了近年来国外对其研究的进展。     

人芽囊原虫标本染色方法的改进

人芽囊原虫标本经肖氏液固定后,用改良的哈氏苏木素染色。结果表明,标本内部结构清晰,中心体明显,与传统的铁苏木素染色方法相比,染色效果好,制片时间短,操作步骤简单。     

人芽囊原虫感染合并其他疾病研究进展

人芽囊原虫是一种常见肠道寄生原虫,感染者一般无明显临床症状,少数感染者尤其是合并感染或免疫系统功能受损者可出现腹痛、腹泻、恶心、呕吐等症状,严重时可能危及生命.本文就人芽囊原虫合并感染其他病原体及其他疾病研究进展作一综述,为人芽囊原虫感染防控提供参考.     

Blastocystis hominis: epidemiology and natural history

To study the demographic profile of Blastocystis hominis carriers from Hamilton, Canada, the Regional Parasitology Laboratory records for 1988 were reviewed, and a prospective study on carriers was conducted to clarify the natural history of the infection and ascertain the role of B. hominis as an intestinal pathogen. Retrospective analysis revealed that 8% of stool samples harbored B. hominis. The median age of the carriers was 37 years; 55% were female. Prospective analysis of 139 patients showed that most (76%) of 86 in whom B. hominis was the sole organism found (and for whom data were complete) continued to harbor the parasite in stool samples submitted a median of 57 days after the first sample. There was no correlation between the presence of B. hominis and symptoms. Thus, B. hominis, though commonly seen in stool samples submitted to this laboratory, is thought to be a commensal organism.     

Effect of trimethoprim-sulfamethaxazole in Blastocystis hominis infection

OBJECTIVE: Blastocystis hominis (B. hominis) is a common intestinal parasite that has long been considered nonpathogenic. Recently there have been many reports supporting a role for the organism as a potential pathogen. We performed a study to examine the pathogenicity of B. hominis and the effect of trimethoprim-sulfamethaxazole (TMP-SMX) on this organism. METHODS: Stool samples of patients, who came to the Department of Parasitology, Faculty of Medicine, Celal Bayar University, were examined by direct wet-mount, trichrome staining, formalin-ethyl acetate concentration, and Kinyoun acid fast techniques for intestinal parasites, and bacteriological stool cultures were performed. Fifty-three symptomatic patients (38 children and 15 adults) with two consequent stool samples positive for abundant B. hominis (five or more organisms per x400 field) and negative for other parasitic and bacterial pathogens were treated with TMP-SMX for 7 days, children 6 mg/kg TMP, 30 mg/kg SMX, and adults 320 mg TMP, 1600 mg SMX, daily. On the seventh day, at the end of treatment, stool samples of all patients were examined by same methods, and clinical symptoms were again evaluated. RESULTS: B. hominis was eradicated in 36 of 38 (94.7%) children, and 14 of 15 (93.3%) adults. Clinical symptoms disappeared in 39 (73.6%), decreased in 10 (18.9%), and no change was observed in one (1.9%) patient, whereas symptoms persisted in all three (5.7%) patients in whom B. hominis could not be eradicated. Mean number of stools per day was significantly decreased from 4.3 to 1.2 in the 33 children (p < 0.001), and decreased from 3.5 to 1.0 in the four adults (p = 0.06) with diarrhea. CONCLUSIONS: These results suggested that B. hominis may be pathogenic, especially when it is present in large numbers, and TMP-SMX is highly effective against this organism. Although there are some anecdotal reports, to our knowledge this is the first study examining the effect of TMP-SMX on B. hominis in humans.     

Questionable clinical significance of Blastocystis hominis infection

In the period from January 1986 to July 1988, Blastocystic hominis was found in moderate and numerous quantities in 103 (1.6%) of 6,262 stool specimens examined in our laboratory. There was no significant association of the detection of B. hominis with travel history or symptoms. Indeed, 20 patients (36%) with moderate to heavy infections had no gastrointestinal symptoms, and three symptomatic patients did not show clinical improvement after elimination of the parasite. Reexamination of stool samples revealed that eight untreated patients had spontaneous disappearance of B. hominis. We conclude that B. hominis probably is not responsible for clinical symptoms when detected, and additional investigations should be pursued for other etiologies of the patient's symptoms.     

Clinical report of Blastocystis hominis infection in children

During a 9-month hospital-based survey, the intestinal parasite Blastocystis hominis was detected in high numbers (five or more organisms per oil immersion field) in faecal specimens from 39 (2%) of 1960 children under 13 years old. Abdominal pain or discomfort with or without diarrhoea was present in 32 children categorized as acute (14), subacute (7) or chronic (11) cases with respective mean ages of 6.4, 7.3 and 8.7 years. They included three with other enteropathogens (Giardia lamblia, Cryptosporidium sp. or Hymenolepis nana). The remaining seven children had no gastrointestinal symptoms. The 14 acute cases (symptoms duration 1-11 days) were characterized by cramp-like abdominal pain, watery diarrhoea and vomiting. The seven subacute (3-4 weeks) and 11 chronic (3-12 months) cases presented with abdominal discomfort and/or loose non-watery stools. Four complained of flatus and eosinophilia was noted in six. All symptoms resolved with eradication of B. hominis or reduction to low numbers after metronidazole chemotherapy (28 cases) or with no treatment (four cases). This study would appear to support the role of the parasite as an enteropathogen in some children. A case control study is clearly needed to clarify the status of B. hominis as a pathogen.     

Blastocystis hominis infection in irritable bowel syndrome patients

Irritable bowel syndrome (IBS) is a functional bowel disorder in which abdominal pain is associated with a defect or a change in bowel habits. Subtle inflammation, especially after infectious enteritis, has been sometimes suspected as one mechanism of pathogenesis. This research was performed (1) to evaluate the prevalence of parasitic infections and (2) the possible association of IBS and parasitic infections. Fifty-nine IBS patients were recruited using symptom-based criteria (Rome Criteria II) with an absence of intestinal parasitic infection by direct smear method. Stool samples of individual patients were examined using 7 methods, ie examination for stool occult blood, simple saline smear method, formalin-ether technique, culture for Blastocystis hominis, modified trichrome stain, modified Ziehl-Neelsen method, and trichrome stain for parasitic and bacterial infections. Of the 59 patients, stool samples of 13 patients (22.1%) were positive for parasites. These were B. hominis (13.6%), Strongyloides stercoralis larvae (1.7%), Giardia lamblia cysts (1.7%), and non-pathogenic protozoa, ie Endolimax nana cysts (5.1%). The prevalence rate of parasitic infections in the control group (20%) was not statistically different from the patients. There was no statistical difference between B. hominis infection in IBS patients and control was found in this study (p = 0.87). In the IBS group, B. hominis infection predominated (13.6%), while other parasitic infections were found in 8.5%. The culture method for B. hominis is more sensitive than the direct (simple) stool smear method, which is the routine diagnostic method in most laboratories. These results were also found in control group.