Septic Shock Due To Pneumocystis Pneumonia In HIV Infected Patients- Is The Virulence Of Pneumocystis Jiroveci Changing?

Pneumocystis jiroveci pneumonia is the most common pulmonary opportunistic infection in patients with human immunodeficiency virus. The mortality for those patients that develop acute respiratory failure requiring mechanical ventilation is as high as 50%. The development of septic shock in those patients is usually due to a superimposed bacterial infection or the presence of other opportunistic infection like Aspergillus, Cryptococcus, systemic Candidiasis or toxoplasmosis. We report a unique case series of four patients with Pneumocystis jiroveci pneumonia with acute respiratory failure and hemodynamic consistent with septic shock. Despite extensive investigation, the sole etiology for the shock was Pneumocystis jiroveci. The mortality for those patients was higher that the reported for a similar population with shock due to bacterial infections. We speculate that this could reflect increasing virulence of Pneumocystis jiroveci, which induce a greater deraignment of the pro and inflammatory system.