ABSTRACT
I. Introduction A major cause morbidity and mortality in patients suffering from Pneumocystis pneumonia (PcP) is the associated impaired gas exchange and resultant clinically significant hypoxemia [1]. The chest radiograph in PcP is often underwhelming in comparison to the alveolar-arterial oxygen gradient, suggesting the presence of severe intrapulmonary shunting and microatelectasis. In addition, altered lung mechanics and increased work of breathing are present.
