Department of Microbiology, University of Karachi, Room No. 113, Karachi, 75270, Pakistan.
Parasitol Res. 2012 Sep;111(3):1357-68. doi: 10.1007/s00436-012-2972-0. Epub 2012 Jul 5.
In this study, we collected data on the incidence of enteric parasites in healthcare-seeking individuals along with their symptoms to quantify the potential roles of factors such as age, sex, and seasonality in infection. We performed analysis to identify factors which could help differentiate parasitic infection from other causes of gastrointestinal illness in a community. The size of the patient population (n = 339), patient selection methodology, collection methods, and statistical analysis followed approaches from similar studies in core clinical journals. Ethical approval was obtained from the University of Karachi's Ethical Review Board. Fecal specimens (n = 339) submitted by symptomatic patients were collected from two clinical laboratories, along with information about the patients' age, sex, and symptoms. We found that symptoms of fever, vomiting, and constipation were 100 % predictive of finding a parasitic infection, while diarrhea was 88 % predictive of a parasitic infection. Gastrointestinal parasite-positive patients reported diarrhea (60 %), vomiting (30 %), fever (25 %) and constipation (25 %), while parasite-negative patients exhibited a symptomatic profile without fever, vomiting, and constipation. The distribution of symptoms in parasite-positive patients remained relatively invariant regardless of the parasite identified. Blastocystis spp.-mono-infected patients reported a similar profile to patients positive for Entamoeba histolytica/Entamoeba dispar and Cryptosporidium spp. Most parasitic infections exhibited a strong seasonal pattern, with a peak incidence in summer months. Infection by Blastocystis spp. was the most prevalent, and it was the only infection mathematically correlated to rainfall by Pearson's method. We observed no increase in healthcare-seeking behavior following a stressful community event, namely, the attempted assassination of Benazir Bhutto in Karachi. The data suggest that parasitological testing would produce a high yield of positive results when performed on healthcare-seeking patients in Karachi in 2007 with symptoms of fever, vomiting, or constipation and a low yield when performed on patients noting only abdominal pain. Parasitological testing also produces a higher yield on patients seen in summer months.
在这项研究中，我们收集了寻求医疗保健的个体中肠道寄生虫感染的发病率及其症状数据，以量化年龄、性别和季节性等因素在感染中的潜在作用。我们进行了分析，以确定有助于区分寄生虫感染与社区中其他胃肠道疾病病因的因素。患者人群规模（n=339）、患者选择方法、采集方法和统计分析均遵循核心临床期刊中类似研究的方法。卡拉奇大学伦理审查委员会批准了这项研究。从两个临床实验室收集了有症状患者的粪便标本（n=339），并收集了患者的年龄、性别和症状信息。我们发现，发热、呕吐和便秘的症状 100%可预测寄生虫感染，而腹泻 88%可预测寄生虫感染。胃肠道寄生虫阳性患者报告腹泻（60%）、呕吐（30%）、发热（25%）和便秘（25%），而寄生虫阴性患者表现为无症状，无发热、呕吐和便秘。无论鉴定出哪种寄生虫，寄生虫阳性患者的症状分布相对不变。单一感染芽囊原虫的患者报告的症状与感染溶组织内阿米巴/迪斯帕内阿米巴和隐孢子虫的患者相似。大多数寄生虫感染呈明显的季节性模式，夏季发病率最高。芽囊原虫感染最为普遍，并且是唯一通过皮尔逊方法与降雨相关的感染。我们没有观察到在卡拉奇发生社区应激事件（贝娜齐尔·布托遇刺未遂）后寻求医疗保健的行为增加。这些数据表明，在 2007 年卡拉奇出现发热、呕吐或便秘症状并寻求医疗保健的患者中进行寄生虫检测，阳性结果的检出率较高，而仅报告腹痛的患者阳性结果的检出率较低。寄生虫检测在夏季月份也有更高的检出率。
