Despite the prevalence of Aspergillus-related disease in immune suppressed lung transplant patients, little is known of the host-pathogen interaction. Because of the mould’s angiotropic nature and because of its capacity to thrive in hypoxic conditions, we hypothesized that the degree of Aspergillus invasion would increase with progressive rejection-mediated ischemia of the allograft. To study this relationship, we utilized a novel orthotopic tracheal transplant model of Aspergillus infection, in which it was possible to assess the effects of tissue hypoxia and ischemia on airway infectivity. Laser Doppler flowmetry and FITC-lectin were used to determine blood perfusion, and a fiber optic microsensor was used to measure airway tissue oxygen tension. Fungal burden and depth of invasion were graded using histopathology. We demonstrated a high efficacy (80%) for producing a localized fungal tracheal infection with the majority of infection occurring at the donor-recipient anastomosis; Aspergillus was more invasive in allogeneic compared to syngeneic groups. During the study period, the overall kinetics of both non-infected and infected allografts was similar, demonstrating a progressive loss of perfusion and oxygenation, which reached a nadir by days 10-12 post-transplantation. The extent of Aspergillus invasion directly correlated with the degree of graft hypoxia and ischemia. Compared to the midtrachea, the donor-recipient anastomotic site exhibited lower perfusion and more invasive disease; a finding consistent with clinical experience. For the first time, we identify ischemia as a putative risk factor for Aspergillus invasion. Therapeutic approaches focused on preserving vascular health may play an important role in limiting Aspergillus infections.

Increased ferric iron in allografts triggers a switch in the growth of the mold Aspergillus fumigatus from a colonizing to an invasive phenotype.

We report a case of propofol infusion syndrome (PRIS) in a young female treated for status epilepticus. In this case, PRIS rapidly evolved to full cardiovascular collapse despite aggressive supportive care in the intensive care unit, as well as prompt discontinuation of the offending agent. She progressed to refractory cardiac arrest requiring emergent initiation of venoarterial extracorporeal membrane oxygenation (ECMO) during cardiopulmonary resuscitation (CPR). She regained a perfusing rhythm after prolonged (>8 hours) asystole, was weaned off ECMO and eventually all life support, and was discharged to home. We also present a review of the available literature on the use of ECMO for PRIS.