Search

Dirofilaria immitis is a parasite transmitted by mosquito bites, where the most common primary hosts are dogs, cats and some wild animals. Humans become accidental hosts after being bitten by an infected mosquito and the number of such infections has rapidly increased during the last decade. We present a patient in which a live D. immitis has been found during myocardial revascularization. To the best of our knowledge, live D. immitis found in the substernal area during open heart surgery has never before been described. D. immitis in humans most often cause pulmonary nodules known as 'coin lesions' which are benign and asymptomatic, but it is very important for thoracic surgery that they are considered in the differential diagnosis of pulmonary nodules. Video assisted thoracic surgery has been proven as the best method for diagnosing and treating pulmonary dirofilariasis., (© The Author 2013. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Trypanosoma cruzi causes Chagas' disease, a systemic infection that affects cells of meso-, endo-, and ectodermic origin. However, as far as we know, the presence of T. cruzi stages in bone has not been reported previously, and it has scarcely been investigated in cartilage. We inoculated 7- and 20-day-old (8 and 15 g) NMRI albino mice i.p. with metacyclic trypomastigotes from Rhodnius prolixus used for xenodiagnosis of mice previously infected with mammalian, human, and triatomines isolates, characterized by randomly amplified polymorphic DNA as zymodeme 1 (equivalent to T. cruzi I). Tissular parasitism (quantified according to the number of pseudocysts/50 fields 400x) showed amastigotes, intermediate forms, or trypomastigotes in sternum chondroblasts, osteoblasts, macrophages, and fibroblasts; chondrocyte and osteocyte invasion was rare. All isolates parasitized bone marrow macrophages, with few amastigotes. We observed marked associated myotropism, with or without inflammatory infiltration; there were small numbers of intensely parasitized mononuclear cells in perichondrium and periosteum. We discuss the results in relation to the marked differences of the T. cruzi tropism toward the different types of sternum cells, and, additionally, we outline the possibility of transmitting parasitized bone marrow through transplants. The fact of finding parasite stages in sternum bone and cartilage may be considered important due to the studies on Chagas' disease paleoparasitology that are based on histological and molecular analysis.