Click on the fibrin thrombus in the section of lung above:

Disseminated intravascular coagulation (DIC) is a consequence of widespread activation of the coagulation system through endothelial injury and/or release of thromboplastic substances into the circulation. DIC can be seen with severe infections, trauma, neoplasia, and obstetric complications, among others. Small fibrin thrombi can form in small arteries of brain, heart, lungs, kidneys, and other organs to produce ischemic tissue damage.