Advances in the biology, pathogenesis and identification of Pneumocystis pneumonia.

PURPOSE OF REVIEW: Pneumocystis pneumonia remains the most prevalent opportunistic infection in patients with AIDS. It is also a common devastating infection in patients with other causes of altered immunity. Though scientific study of this fungal pathogen is challenging given the inability to propagate the organism outside of the host lung, studies utilizing advanced molecular techniques and genomic analysis have broadened our understanding of the epidemiology and pathogenesis of Pneumocystis and will be described herein.

RECENT FINDINGS: Results from advanced molecular techniques suggest that Pneumocystis organisms not only cause infection in patients with impaired immunity but also colonize mammals with normal immune systems. Advanced technology has also identified acquired Pneumocystis genetic mutations that confer resistance to currently utilized therapeutics. Though not yet widely utilized in clinical medicine, advanced polymerase chain reaction techniques improve the diagnostic yield of respiratory specimen analysis. Preliminary results from serum beta-glucan testing suggest that a noninvasive marker of Pneumocystis pneumonia infection and response to therapy may be on the horizon.

SUMMARY: Recent scientific advances suggest opportunities for improving the diagnosis and treatment surveillance of Pneumocystis pneumonia. Further investigations are necessary to define the optimal characteristics of these laboratory tests and to develop therapeutics directed at novel Pneumocystis genomic targets.