How is pathogen-host interaction of pneumocystitis?

Macrophages mediate their clearance, by phagocytosis, respiratory burst and inflammation after seeing beta-glucan molecules present at cell wall and MSG (major surface glycoprotein). In HIV pt these are impaired, risk factors include immunosupression with no ART, CD4<200, previous episodes of PCP, oral thrush, recurrent pneumonia, weight loss.