Histomorphological characteristics of Ascaris lumbricoides and Taeniarhynchus saginatus

Introduction: Ascaridosis and taeniarhynchosis are chronic intestinal parasitic diseases, caused by the multicellular helminthes - Ascaris lumbricoides and Taeniarhynchus saginatus. A. lumbricoides is the largest nematode found in the human intestines with the female organism reaching lengths between 20 and 40 centimeters. T. saginatus is a hermaphroditic cestode reaching lengths from 6 up to 10 meters. Aim: The aim was to prepare histological tissue sections and to present the specific microscopic structure of the intestinal helminthes using different staining techniques. Material and methods: We used museum preparations of adult worms, fixed in a 10% formalin solution. Histological tissue sections were prepared and stained with hemalaun-eosin technique, Heidenhein's azan, van Gieson's trichrome stain and acetic orcein after Taenzer-Unna. Results and discussion: The preparations stained with hemalaun-eosin allowed us to observe and describe the morphology and positioning of the internal organs of the intestinal parasites, while the special stains allowed the differentiation of some specific morphological elements like the fine structure of the cuticle of A. lumbricoides, cestodal eggs' morphology etc. Conclusions: The histological sections allowed a detailed examination of the helminthes' internal morphology. Although in the routine diagnostic practice for intestinal parasites more efficient tests are available, the histological samples stained with different techniques can provide useful information in studying the morphology in the ongoing education of the specialists in human and veterinarian parasitology, biology and laboratory technicians.