In special coagulation, think horses not zebras: A clotted sample from a patient with congenital disorder of glycosylation

Herein, we describe an interesting case of non-parallelism in coagulation factor activity assays observed in a sample collected from a 4-year-old patient with a congenital disorder of glycosylation (CDG), and emphasise the importance of rigorously assessing for pre-analytical variables when interpreting atypical patterns in coagulation factor activity testing.