Abdominal angiostrongyliasis is caused by Angiostrongylus costaricensis, the definitive and intermediate hosts of which are wild rodents and terrestrial molluscs, respectively. Humans are accidental hosts and can be infected by ingesting the third-stage (infective) larvae (L3). It remains unclear whether the number of L3 inoculated is related to lesion severity. Our aim was to analyse histopathological alterations in Swiss mice infected with different doses of A. costaricensis. Thirty-two mice were randomly divided into four groups (n = 8/group): uninfected, control mice; mice infected with a low dose (five L3); mice infected with an intermediate dose (15 L3); and mice infected with a high dose (30 L3). The frequency of intestinal thrombi, splenitis, eggs/larvae, hepatic infarction and acute pancreatitis differed among the groups, the last being considered a significant finding. We conclude that different infective doses alter the histopathological aspects of the infection in Swiss mice, those aspects being more pronounced at medium and high doses, with no effect on the development of the disease. This experimental model shows that the parasite life cycle can be maintained in Swiss mice through the inoculation of a low dose (five L3).

中文翻译：

---

腹部血管圆线虫病：感染不同剂量哥斯达黎氏管圆线虫的瑞士小鼠的病理结果

腹部血管圆线虫病是由以下原因引起的哥斯达黎加管圆线虫，其最终宿主和中间宿主分别是野生啮齿动物和陆生软体动物。人类是偶然的宿主，可以通过摄入第三阶段（感染性）幼虫（L3）而被感染。目前尚不清楚接种 L3 的数量是否与病变严重程度有关。我们的目的是分析感染不同剂量的瑞士小鼠的组织病理学改变。A.哥斯达黎加。32只小鼠随机分为四组（n= 8/组）：未感染的对照小鼠；用低剂量（5 L3）感染的小鼠；用中等剂量（15 L3）感染的小鼠；和用高剂量（30 L3）感染的小鼠。肠血栓、脾炎、虫卵/幼虫、肝梗塞和急性胰腺炎的发生率在各组之间存在差异，最后一项被认为是重要发现。我们得出结论，不同的感染剂量会改变瑞士小鼠感染的组织病理学方面，这些方面在中等和高剂量时更为明显，对疾病的发展没有影响。该实验模型表明，通过接种低剂量（5 L3），可以维持瑞士小鼠体内的寄生虫生命周期。