Serpiginous lesion on the foot

Helminthic infestation was suspected, but two stool samples were negative for ova, cysts and parasites. Further questioning about the pureed food that had been given to the infant (banana mash mixed with Farex baby food and boiled tank water) revealed that the mixture formed the same appearance of small, red, thread-like structures when left to stand overnight. Treatment of intestinal helminth infection is often with a single dose of albendazole or mebendazole. However, the objects noted in the stool of this baby were artefact (plant fibres), and the family was reassured that no treatment was required. The child remained well without any intervention. Intestinal helminth infections affect more than 1.5 billion people worldwide, particularly school-aged children and adolescents. In suburban Australia, the pinworm (Enterobius vermicularis) is the commonest helminth. Infestation with roundworm (Ascaris lumbricoides), whipworm (Trichuris trichiura) or hookworm (Necator americanus and Ancylostoma duodenale) may be seen in returning travellers and indigenous communities in northern Australia. Helminthic infections are usually diagnosed when parasites or their eggs are seen in stool samples. Several artefacts, such as plant cells and fibres can resemble worms or their eggs, but careful macroscopic and microscopic examination of the faeces can differentiate these artefacts from true parasitic infection.