Schistosomiasis is a disease that, in Brazil, is caused by Schistosoma mansoni and is transmitted by snails of the genus Biomphalaria. This species occurs in Africa, the Antilles and South America. The parasite, developing to the adult stage in the vascular system of the host, migrates to the mesenteric veins. Each female lays approximately 400 eggs per day, and these travel from the submucosa to the intestinal lumen. There have been reported cases in which S. mansoni eggs were identified in the lungs of patients with no evidence of liver fibrosis. We report a case with this atypical presentation of the disease. The patient presented nonpleuritic chest pain, significant weight loss and dry cough. A CT scan revealed an irregular tumor in the left lower lobe. However, a lung biopsy revealed non-viable S. mansoni eggs. The patient presented no clinical signs of pulmonary or portal hypertension; nor was either identified through diagnostic tests.

Keywords: Schistosomiasis; Schistosoma mansoni; Lung diseases, parasitic.