Critical green inclusions are a rare finding, and when found they are suggestive of a poor prognosis, hence the colloquial term death crystals. A 2018 review found that 56% of patients died shortly after the inclusions were first identified (usually within two weeks).[5] However, critical green inclusions are of limited utility for predicting mortality because they are usually found in severely ill patients whose poor prognosis is already evident for other reasons by the time the crystals are detected.[6]