Background: Septic and amniotic fluid emboli are rare sources of pulmonary embolism (PE), so the present study sought to elucidate the background of these cases.
Methods and results: A total of 11,367 PE cases were identified from 396,982 postmortem examinations. The incidence of septic PE was 247 (2.2%) of the total. The origin of infection was found in 85.6% of the cases. Fungal embolus was detected more often than bacterial embolus. The most frequently detected fungus was aspergillus (20.8%). The primary disease associated with fungal embolus was leukemia (43.2%). The incidence of PE cases associated with pregnancy and/or delivery was 89 (0.8%) of the total PE cases. Among them, amniotic fluid embolism was found in 33 (73.3%) of 45 PE cases with vaginal delivery, and in 7 (21.2%) of 33 PE cases with cesarean delivery (p<0.0001).
Conclusion: Fungal embolus was more frequent than bacterial embolus, and leukemia was most frequent as the primary disease in cases of fungal embolus. The main cause of PE in cesarean section cases was thrombotic embolism, and the main cause in vaginal delivery cases was amniotic fluid embolism.