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Medical Term:

Pneumocystis jiroveci pneumonia


Definition: pneumonia resulting from infection with Pneumocystis jiroveci, frequently seen in the immunologically compromised, such as people with AIDS, or those treated with steroids, the elderly, or premature or debilitated babies during their first 3 months. In AIDS patients, tissue damage is usually restricted to the pulmonary parenchyma, whereas in the infantile form of the disease the alveoli are filled with a honeycomblike or foamy network of acidophilic material, apparently not fibrin and not stainable with silver, within which the organisms, individually or in aggregates, are enmeshed; throughout the alveolar walls and pulmonary septa there is a diffuse infiltration of mononuclear inflammatory cells, chiefly plasma cells and macrophages, as well as a few lymphocytes. Patients may be only slightly febrile (or even afebrile), but are likely to be extremely weak, dyspneic, and cyanotic. This is a major cause of morbidity among patients with AIDS.

Synonym(s): interstitial plasma cell pneumonia, pneumocystosis

See Also: Pneumocystis jiroveci

© Copyright 2016 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.