Suspected toxoplasma-associated myocarditis in a cat

Abstract

Clinical toxoplasmosis is commonly reported in the cat, with the most consistent findings being ocular, pulmonic, hepatic, neurological, gastrointestinal and muscular abnormalities. Myocarditis, whilst frequently identified at post-mortem examination, has not been identified ante-mortem. In immunocompromised humans, myocarditis associated with toxoplasmosis is not an uncommon complication. In such cases, lymphocytic myocardial infiltration can lead to depressed myocardial function, which can be associated with congestive heart failure, rhythm disturbances and pericardial effusions. In addition, myocardial failure has been reported in immunocompetent humans associated with active toxoplasmosis [Chandenier J, Jarry G, Nassif D, Douadi Y, Paris L, Thulliez P, Bourges-Petit E, Raccurt C (2000) Congestive heart failure and myocarditis after seroconversion for toxoplasmosis in two immunocompetent patients. European Journal of Clinical Microbiological Infectious Disease 19, 375-379]. Here we describe a cat with echocardiographic changes consistent with infiltrative or inflammatory disease, and elevated IgG and IgM titres to Toxoplasma gondii. There was resolution of these myocardial changes once the toxoplasmosis was treated.

Fig 1.

Lateral thoracic radiograph: an airgun pellet can be seen at the level of the fifth rib. A generalised mild increase in the bronchointerstitial markings can be appreciated. In addition, the cardiac silhouette is enlarged, giving the heart a globoid appearance.

Fig 2.

Right parasternal long axis view at the atrial level. The thickened interatrial septum (IAS) is clearly visible, as is the hypertrophy of the right ventricular free wall (RVFW).

Fig 3

Left apical four chamber view demonstrating the nodular interatrial septum (IAS), thickening of the right ventricular free wall (RVFW) and a moderate pericardial effusion (PE).