Dirofilaria repens Parasite: Review with Emphasis on Ultrasound Findings with Looking for Worm Mobility

Jacques Malghem; Bruno Vande Berg; Benoît Lengelé; Frédéric Lecouvet

doi:10.5334/jbsr.4072

Dirofilaria repens Parasite: Review with Emphasis on Ultrasound Findings with Looking for Worm Mobility

Journal of the Belgian Society of Radiology

Volume 110 (2026): Issue 1

By: Jacques Malghem, Bruno Vande Berg, Benoît Lengelé and Frédéric Lecouvet

Open Access

|Mar 2026

Abstract

Human dirofilariasis is caused by infection with a parasite relatively common in dogs. Occasional transmission of larvae to humans occurs via an insect bite and development of an immature worm at the bite site. The disease, once confined to southern Europe, is becoming increasingly widespread, particularly due to global warming. Clinical signs are nonspecific and laboratory findings usually normal. Imaging shows pseudotumor features also nonspecific on computed tomography (CT) and magnetic resonance imaging (MRI) scans. Ultrasound may suggest the diagnosis by the presence of double echogenic ‘rail’ images. However, only spontaneous motility of the parasite observation can confirm the diagnosis.

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Articles in this issue

DOI: https://doi.org/10.5334/jbsr.4072 | Journal eISSN: 2514-8281

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Language: English

Submitted on: Aug 14, 2025

Accepted on: Feb 18, 2026

Published on: Mar 26, 2026

Published by: Ubiquity Press

In partnership with: Paradigm Publishing Services

Publication frequency: 1 issue per year

Keywords:

Dirofilaria,

parasite,

human dirofilariasis,

soft tissues tumor,

imaging,

ultrasound

© 2026 Jacques Malghem, Bruno Vande Berg, Benoît Lengelé, Frédéric Lecouvet, published by Ubiquity Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 110 (2026): Issue 1