Negative role of malnutrition in cell-mediated immune response: Pneumocystis jirovecii pneumonia (PCP) in a severely malnourished, HIV-negative patient with anorexia nervosa.

It is generally acknowledged that malnutrition is a propensity factor for secondary infections in different clinical situations (malnutrition-associated infections in hospitalized patients and malnourished children in developing countries). However, it is not clear how malnutrition might facilitate the development of opportunistic infections in human immunodeficiency virus (HIV)-negative patients without a definite etiology (disease or treatment) of impaired cell-mediated immune response. We report here on a case of Pneumocystis jirovecii pneumonia in an HIV-negative patient suffering from anorexia nervosa with extreme malnutrition, which had a favorable outcome despite the severity of her respiratory failure. This report indicates the need for the early screening of nutritional status and rapid treatment initiation in patients with malnutrition, as well as the determination of opportunistic infections in the event of a low lymphocyte count.