Chronic interstitial pneumonitis in dogs naturally infected with Leishmania (Leishmania) chagasi: a histopathological and morphometric study

Abstract

SUMMARYEighteen mongrel dogs of unknown age and naturally infected with Leishmania (Leishmania) chagasi, were obtained from the City Hall of Belo Horizonte, Brazil. Four dogs were used as control. Lung samples were obtained and immediately fixed in formalin. The histopathological picture of all lung tissue sections was a chronic and diffuse interstitial pneumonitis. The thickened interalveolar septa were characterized by the cellular exudate (mostly macrophages, lymphocytes and plasmocytes) associated with collagen deposition. Morphometric analysis showed greater septal thickness in the infected animals than in controls. In fact, the morphometric study of collagen stained with ammoniac silver confirmed a larger deposition of collagen in the infected animals. The parasitologic method was carried out during the study of the lesions on the slides. However, we did not observe any correlation between the histopathologic and morphometric data and the clinical status of the animals. We conclude that the pulmonary lesions observed in all naturally infected dogs were correlated with the disease and that the morphometric method used was satisfactory for the analysis of septal thickness and of increased collagen deposition, confirming the presence of fibrosis.

Cardiac and pulmonary alterations in symptomatic and asymptomatic dogs infectednaturally with Leishmania (Leishmania) chagasi

“…Respiratory alterations include dyspnea, rhinitis, mucocatarrhal nasal discharge, epistaxis, stertorous breath sounds, and chronic interstitial pneumonitis (16,(19)(20)(21). Secondary bacterial or fungal inflammatory processes can be observed in immunosuppressive states, and pneumonia acquires a suppurative aspect (22).…”

RADIOGRAPHIC FINDINGS OF UREMIC PNEUMONITIS IN DOGS WITH CHRONIC RENAL FAILURE / Achados radiográficos de pneumonite urêmica em cães com insuficiência renal crônica.

“…There are contradictions regarding the term pneumonitis. Some authors use it as a synonym for pneumonia while others prefer terms such as pneumonia uremic syndrome (FAUBEL, 2008) or interstitial pneumonitis (DROST, 1997;GONÇALVES, et al, 2003). The term pneumonitis was used in this work to qualify on radiographic images increased diffuse radiopacity of the pulmonary interstitium, classified as interstitial pattern, associated with thickening bronchioles and vasculitis.…”

Protozoa in respiratory pathology: a review

“…is characterised by chronic diffuse interstitial pneumonitis with thickening of the alveolar septa due to the depositing of collagen and a cellular exudates formed principally by macrophages, lymphocytes and plasmatic cells [84]. A similar pulmonary pathology involving foci of septal fibrosis and interstitial pneumonitis with a predominance of mononuclear cells has also been described in humans [85].…”