Department of Pathology, General Hospital “G. Papanikolaou”, Thessaloniki, Greece
Background: Dirofilariasis is a zoonosis transmitted by mosquitoes from animals to human beings. The most common symptoms include cough, chest pain, fever, eosinophilia and hemoptysis. Some patients may be asymptomatic.
Objective: The report of an interesting case of this rare disease.
Case presentation: A 45-year-old female presented to our hospital with cough, dyspnea and fever. The radiological evaluation revealed a coin lesion, measuring 1.3 cm at the right upper lobe. The patient underwent partial lobectomy due to a suspected neoplasm. Frozen section excluded the presence of neoplastic cells. The histological examination showed a necrotic nodule, well demarcated from surrounding lung parenchyma by fibrous connective tissue, histiocytes and multinucleated giant cells. Worms of Dirofilaria were embedded in the center of necrotic nodule.
Conclusions: Five species of Dirofilaria are known to cause infections in humans (D. immitis: lung parenchyma infection, D. tenuis or D. conjunctivae: subcutaneous nodules in face, conjunctiva of the eye, chest wall, abdominal wall as well as D. repens, D. ursi and D. subdermata). Human pulmonary dirofilariasis is a rare entity, however it should be included in the differential diagnosis in patients with small, solitary pulmonary necrotic nodules.