Genta R M, Schad G A
Vet Pathol. 1984 May;21(3):349-54. doi: 10.1177/030098588402100313.
Filaroides hirthi is a pulmonary parasite found primarily in beagle dogs. The modes of transmission and the life cycle of this parasite have been described recently, and the possibility of an autoinfectious cycle has been suggested. In this paper, we report two cases of experimentally immunosuppressed beagles (4 mg/day of prednisolone for over four months) in which massive disseminated F. hirthi infections developed. Large numbers of F. hirthi adults were present in the lungs, and larvae were found in lungs, mesenteric nodes, intestinal walls, and liver. While only minimal cellular responses were associated with the adult worms, a conspicuous mononuclear cell reaction was found around the larvae in the tissues. Since our dogs were caged to minimize contact with their own feces, we suggest that autoinfection took place in these dogs. Heavy worm burdens probably were reached because the reduced immune responses against the larva facilitated their successful penetration of the intestinal wall and their recirculation within the host.
赫氏丝状线虫是一种主要在比格犬体内发现的肺部寄生虫。该寄生虫的传播方式和生命周期最近已有描述，并且有人提出了自身感染循环的可能性。在本文中，我们报告了两例实验性免疫抑制的比格犬（每天服用4毫克泼尼松龙超过四个月），它们发生了大量播散性赫氏丝状线虫感染。肺内存在大量赫氏丝状线虫成虫，在肺、肠系膜淋巴结、肠壁和肝脏中发现了幼虫。虽然与成虫相关的细胞反应很轻微，但在组织中的幼虫周围发现了明显的单核细胞反应。由于我们将犬关在笼中以尽量减少其与自身粪便的接触，我们认为这些犬发生了自身感染。可能由于针对幼虫的免疫反应降低，促进了幼虫成功穿透肠壁并在宿主体内再循环，从而导致了大量的虫负荷。
