Actinomyces infection in a dog with pulmonary carcinoma

Abstract

Thoracic actinomycosis was diagnosed by bacterial isolation in a dog with a history of chronic productive cough, weight loss, pyrexia and a pulmonary mass lesion on radiography. Therapy with amoxycillin and clindamycin did not significantly improve the patient's condition and euthanasia was performed during exploratory thoracotomy. Histological examination of the affected lung lobes revealed the presence of peribronchiolar adenocarcinoma. Actinomycosis has been reported to co-exist with pulmonary neoplasia in humans and may mask the presence of malignancy.

Pulmonary actinomycosis in two chamois (Rupicapra rupicapra)

“…In human medicine-pathology, these findings always represent an accurate etiological confirmation of pulmonary actinomycosis (de Montpreville et al 1999;Chouabe et al 2002). Pulmonary actinomycosis is a rare pathological condition mostly characterized by tumor-like pyogranulomatous lesion formation that is frequently misdiagnosed as lung malignancy in humans and domestic animals (Davies and Lucas 2003). Bacteriological confirmation of actinomycosis is rarely carried out because bacteria belonging to the Actinomyces genus are difficult to culture (Hotchi and Schwarz 1972;Mabeza and Macfarlane 2003).…”

“…Such conditions include pre-existing or concurrent states of immunosuppression (Baron et al 1979), lung pathological processes such as malignancy (Dentale et al 1998;Davies and Lucas 2003), and bacterial infections (Tietz et al 2005) that may cause severe defects in lung clearance and in airway mucosal barrier. Both actinomycotic lesions examined in this study were associated with pulmonary helminthiasis.…”