Infectious disease: Lung: HIV: Pneumocystis pneumonia
A 1974 autopsy specimen from a 25 year old male who died on ITU of multiorgan failure. The lung shows the features of Pneumocystis pneumonia. This is most frequently seen in patients with HIV infection towards the end of their illness. It reflects a deficiency in cell mediated immunity. Other predisposing causes of Pneumocystis jirovecii pneumonia include prolonged steroid chemotherapy and malnutrition in infants and neonates. The organism Pneumocystis jirovecii is a ubiquitous fungus which is present in the atmosphere and soil. It is harmless in immunocompetent people.