Dirofilariasis as a cause of focal and pathological lung lesions

The incidence of dirofilariasis in humans is increasing worldwide. Dirofilariasis is the only mosquito-borne transmissible helminthiasis recorded in the Russian Federation. The definitive hosts of this helminth are dogs, cats, and wild predators; humans are rarely infected. The most common infections in humans and animals are caused by Dirofilaria repens and Dirofilaria immitis. The main sites of dirofilaria infestation in humans are the subcutaneous tissue, periorbital area, and lungs. Pulmonary dirofilariasis is usually asymptomatic, detected as a focal or pathological lesion on chest X-ray. Currently, noninvasive laboratory diagnostic methods for dirofilariasis are lacking; diagnosis is established by histological examination of lung tissue. Treatment of the disease is usually surgical.

The aim of the work was to demonstrate and discuss in detail the epidemiology, clinical picture, approaches to diagnosis and treatment of two clinical observations of the classic low-symptom course of pulmonary dirofilariasis. Surgical intervention was necessary to exclude a malignant lung tumor. The epidemiological features, clinical, radiological, and pathological presentation of the disease, complications, and patient management are discussed.

Conclusion. Pulmonary dirofilariasis should be considered in the differential diagnosis of focal and pathological lung lesions.

Improvement of noninvasive laboratory methods for detecting this helminthiasis in humans is necessary.

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